| intended release and actual retention of alfalfa leafcutting bees (hymenoptera: megachilidae) for pollination in commercial alfalfa seed fields. | low, medium, and high stocking densities (15,000; 30,000; and 45,000-50,000 bees per acre, respectively) of megachile rotundata (f.) (hymenoptera: megachilidae), the alfalfa leafcutting bee, were released over 4 yr in three research plots of utah alfalfa, medicago sativa l. (fabaceae), planted at seed-production rates. a low percentage of bees (46-79% of released) survived the incubation and field-emergence processes; of those bees, the number of females that established at the nesting sites was ... | 2013 | 23786042 |
| variation in alfalfa leafcutting bee (hymenoptera: megachilidae) reproductive success according to location of nests in united states commercial domiciles. | the alfalfa leafcutting bee, megachile rotundata f., is used extensively to pollinate alfalfa for seed production in western north america. however, it usually is not possible to sustain bee populations in the united states. in the managed pollination system, variable microenvironments are experienced by developing m. rotundata during the nesting season that may influence bee reproductive success. in this study, bee cells were produced in a small alfalfa field and collected from domiciles accord ... | 2013 | 23786038 |
| duration and frequency of a high temperature pulse affect survival of emergence-ready megachile rotundata (hymenoptera: megachilidae) during low-temperature incubation. | synchronizing megachile rotundata (f.) nesting activity with alfalfa bloom is essential for ensuring optimal pollination for alfalfa seed production. this is achieved by timing the initiation of spring bee incubation so that adults will emerge -2 wk before peak bloom. if weather conditions change so as to delay the bloom, bee managers will commonly expose the developing bees to a period of low-temperature incubation to slow their development. we have previously demonstrated survival during low-t ... | 2012 | 22420249 |
| temperature stress affects the expression of immune response genes in the alfalfa leafcutting bee, megachile rotundata. | environmental stresses are thought to be associated with increases in disease suceptibility, attributable to evolutionary trade-offs between the energy demands required to deal with stress vs pathogens. we compared the effects of temperature stress and pathogen exposure on the immune response of a solitary bee, megachile rotundata. using an oligonucleotide microarray with 125 genes (375 probes), we determined that both high and low temperatures increased the expression of immune response genes i ... | 2012 | 22356318 |
| effect of temperature on post-wintering development and total lipid content of alfalfa leafcutting bees. | temperature plays an important role in effective management of the alfalfa leafcutting bee [megachile rotundata (f.); megachilidae], the major commercial pollinator of seed alfalfa [medicago sativa (l.); fabaceae] in north america. to improve our understanding of threshold and optimum rearing temperatures of m. rotundata, we examined the effect of temperature on postwintering development by using a greater number of temperature treatments than applied in previous studies (19 versus eight or fewe ... | 2011 | 22251693 |
| chalkbrood transmission in the alfalfa leafcutting bee: the impact of disinfecting bee cocoons in loose cell management systems. | understanding pathogen transmission could illuminate new methods for disease prevention. a case in point is chalkbrood in the alfalfa leafcutting bee [megachile rotundata (f.)]. propagation of this solitary bee is severely hampered by chalkbrood, a larval disease caused by ascosphaera aggregata (ascomycota). alfalfa leafcutting bees nest in existing cavities in wood or hollow reeds and overwinter as larvae. in the early summer, emerging adults frequently must chew through dead, diseased siblings ... | 2011 | 22251678 |
| foraging range of honey bees, apis mellifera, in alfalfa seed production fields. | a study was conducted in 2006 and 2007 designed to examine the foraging range of honey bees, apis mellifera (hymenoptera: apidae), in a 15.2 km(2) area dominated by a 128.9 ha glyphosate-resistant roundup ready® alfalfa seed production field and several non-roundup ready alfalfa seed production fields (totaling 120.2 ha). each year, honey bee self-marking devices were placed on 112 selected honey bee colonies originating from nine different apiary locations. the foraging bees exiting each apiary ... | 2011 | 22224495 |
| a fluctuating thermal regime improves survival of cold-mediated delayed emergence in developing megachile rotundata (hymenoptera: megachilidae). | a significant concern in the commercial application of the alfalfa leafcutting bee, megachile rotundata (f.) (hymenoptera: megachilidae), for pollination is synchronizing bee emergence and activity with peak crop bloom. previous studies have demonstrated that the commercial spring incubation of this species can be successfully interrupted by low temperature incubation, thereby slowing development and giving producers flexibility in timing emergence to weather conditions or crop bloom. in this st ... | 2011 | 21882678 |
| effects of the insect growth regulator, novaluron on immature alfalfa leafcutting bees, megachile rotundata. | alfalfa leafcutting bees, megachile rotundata f. (hymenoptera: megachilidae), are the most common pollinators of alfalfa in the pacific northwest. reports from users of m. rotundata in idaho, utah and colorado have indicated exceptionally poor bee return from fields treated with novaluron to control lygus spp. our goal was to evaluate novaluron toxicity to immature m. rotundata using two different possible mechanisms of exposure. one goal was to assess immature mortality via treating nectar-poll ... | 2011 | 21539417 |
| the alfalfa leafcutting bee, megachile rotundata: the world's most intensively managed solitary bee. | the alfalfa leafcutting bee (alcb), megachile rotundata f. (megachildae), was accidentally introduced into the united states by the 1940s. nest management of this eurasian nonsocial pollinator transformed the alfalfa seed industry in north america, tripling seed production. the most common alcb management practice is the loose cell system, in which cocooned bees are removed from nesting cavities for cleaning and storage. traits of alcbs that favored their commercialization include gregarious nes ... | 2011 | 20809804 |
| interrupted incubation and short-term storage of the alfalfa pollinator megachile rotundata (hymenoptera: megachilidae): a potential tool for synchronizing bees with bloom. | a useful technique for synchronizing pollinators with the alfalfa, medicago savita l. (fabaceae), bloom is to interrupt the late spring incubation of developing bee pupae and pharate adults of megachile rotundata (f.) (hymenoptera: megachilidae) with short-term low-temperature storage. however, low-temperature exposure can be stressful depending on the temperature, duration of exposure, and the developmental stage exposed. to evaluate the effect of low-temperature storage after development had a ... | 2010 | 20429433 |
| nest establishment, pollination efficiency, and reproductive success of megachile rotundata (hymenoptera: megachilidae) in relation to resource availability in field enclosures. | the alfalfa leafcutting bee, megachile rotundata (fabricius), is used to pollinate alfalfa, medicago sativa l., for seed production in the united states and canada. it is difficult to reliably sustain commercial m. rotundata populations in the united states because of problems with disease, parasites, predators, and unexplained mortality. one possible explanation for early immature mortality is that, relative to floral availability, superfluous numbers of bees are released in alfalfa fields wher ... | 2010 | 20146851 |
| genes related to immunity, as expressed in the alfalfa leafcutting bee, megachile rotundata, during pathogen challenge. | virtually nothing is known about disease resistance in solitary bees, so expressed sequence tag (est) databases were developed to search for immune response genes in the alfalfa leafcutting bee. we identified 104 putative immunity-related genes from both healthy and pathogen-challenged bee larvae, and 12 more genes using pcr amplification. the genes identified coded for proteins with a wide variety of innate immune response functions, including pathogen recognition, phagocytosis, the prophenolox ... | 2009 | 19863668 |
| prewinter management affects megachile rotundata (hymenoptera: megachilidae) prepupal physiology and adult emergence and survival. | the alfalfa leafcutting bee, megachile rotundata f. (hymenoptera: megachilidae), is widely used as a pollinator for production of alfalfa, medicago sativa l., seed, and populations of these bees can be maintained by alfalfa seed growers or can be purchased from mostly canadian bee providers. m. rotundata raised in canada have higher survival rates during the incubation that occurs after winter storage than do bees produced in the northwestern united states, but no reason has been found for this ... | 2009 | 19736750 |
| fungicide tests on adult alfalfa leafcutting bees (hymenoptera: megachilidae). | chalkbrood is a serious disease of alfalfa leafcutting bee megachile rotundata (f.) (hymenoptera: megachilidae) larvae, causing upward of 20% infection in the field. the causative agent is the fungus ascosphaera aggregata. this bee is used extensively for alfalfa seed pollination in the united states. using laboratory bioassays, we previously demonstrated that fungicides can reduce chalkbrood levels in the larvae. here, we evaluate the toxicity of four fungicides, benlate, captan, orbit, and rov ... | 2008 | 18767714 |
| do weather conditions correlate with findings in failed, provision-filled nest cells of megachile rotundata (hymenoptera: megachilidae) in western north america? | cavity-nesting alfalfa leafcutting bees, megachile rotundata (f.) (hymenoptera: megachilidae), are excellent pollinators of alfalfa, medicago savita l., for seed production. in commercial settings, artificial cavities are placed in field domiciles for nesting and, thereby, bee populations are sustained for future use. for this study, cells from leafcutting bee nests were collected in late summer from commercial seed fields. over 3 yr (2003-2005), 39 samples in total of approximately equal to 1,0 ... | 2008 | 18613565 |
| laboratory bioassays to evaluate fungicides for chalkbrood control in larvae of the alfalfa leafcutting bee (hymenoptera: megachilidae). | chalkbrood, a fungal disease in bees, is caused by several species of ascosphaera. a. aggregata is a major mortality factor in populations of the alfalfa leafcutting bee, megachile rotundata (f.) (hymenoptera: megachilidae) used in commercial alfalfa seed production. four formulated fungicides, benlate 50 wp, captan, orbit, and rovral 50 wp were tested in the laboratory for efficacy against hyphal growth of a. aggregata cultures. the same fungicides, with the addition of rovral 4 f, were tested ... | 2008 | 18613563 |
| [effects of imidacloprid on arthropod community structure and its dynamics in alfalfa field]. | with species richness (s), individual number (n), shannon's index (h') and evenness (e) as the indices of biodiversity, this paper studied the arthropod community structure and its seasonal dynamics in alfalfa field under effects of imidacloprid. the results showed that imidacloprid more affected the species number of natural enemies rather than that of insect pests, resulting in a significant increase of the dominance concentration of both total arthropod community and pest sub-community, but s ... | 2007 | 18163327 |
| effects of the insecticide phosmet on solitary bee foraging and nesting in orchards of capitol reef national park, utah. | capitol reef national park, in southcentral utah, contains 22 small orchards planted with antique fruit varieties by mormon pioneers beginning over a century ago. the orchards continue to be managed in a pick-and-pay program, which includes spraying with phosmet to suppress codling moth (cydia pomonella l.). the park is also home to a rich diversity of flowering plants, many of which are rare, bee-pollinated, and have populations within 1 km of the orchards. over 3 yr, we studied the short-term ... | 2007 | 17716471 |
| thermal history influences diapause development in the solitary bee megachile rotundata. | respiration rate, time to pupation and the expression patterns of selected genes were examined during the diapause to post-diapause transition in the alfalfa leafcutting bee, megachile rotundata held at constant 4 degrees c in winter storage. respiration quotients were at or below 0.7 from december to may and then increased to over 0.8 in june and july. the time required for prepupae to reach the pupal stage following transfer to 29 degrees c decreased from 23 days in december to 10 days in july ... | 2006 | 17049551 |
| effects of three-dimensional and color patterns on nest location and progeny mortality in alfalfa leafcutting bee (hymenoptera: megachilidae). | abstract in alfalfa, medicago sativa l., seed production where high bee densities are released, alfalfa leafcutting bee, megachile rotundata (f.) (hymenoptera: megachilidae), females may enter several nesting holes before locating their nests. such levels of "wrong hole" visits lead to an increase in the time spent by females locating their own nests, thereby decreasing alfalfa pollination efficiency and possibly healthy brood production. the objectives of this study were to determine the effect ... | 2006 | 16813291 |
| emergence success and sex ratio of commercial alfalfa leafcutting bees from the united states and canada. | samples of overwintering alfalfa leafcutting bee, megachile rotundata (f.) (hymenoptera: megachilidae), cells were sent to the laboratory as loose cells or in nesting boards from bee managers in the united states and in canada. x-radiographs of cells were used for determining cell contents. cells containing live prepupae were incubated, and the sex of emerging adults was recorded daily. cells from which no adult emerged were dissected to determine the developmental stage of dead bees and sex of ... | 2005 | 16539094 |
| impact of disinfecting nesting boards on chalkbrood control in the alfalfa leafcutting bee. | the alfalfa leafcutting bee, megachile rotundata (f.), is a solitary, cavity-nesting bee that has been managed in large numbers to pollinate alfalfa, medicago spp., seed crops since the 1960s. propagation of these bees from 1 yr to the next has been seriously hampered by chalkbrood, a larval disease caused by the fungus ascosphaera aggregata skou. in the united states, attempts to control the disease have been fairly unsuccessful, but include removing nests from the nesting boards and then disin ... | 2005 | 16156558 |
| alfalfa leafcutting bee population dynamics, flower availability, and pollination rates in two oregon alfalfa fields. | since the 1970s, it has become increasingly difficult for u.s. alfalfa seed producers to maintain megachile rotundata (f.) populations used for alfalfa, medicago sativa l., pollination. in 1998, we monitored m. rotundata population dynamics and foraging behavior, as well as alfalfa bloom and pollination rates in two fields in eastern oregon. despite marked differences in bee management, establishment was very similar in the two fields (approximately 0.5 females per nesting cavity) and lagged pea ... | 2005 | 16156556 |
| ascosphaera aggregata contamination on alfalfa leafcutting bees in a loose cell incubation system. | the alfalfa leafcutting bee, a solitary bee used to pollinate alfalfa seed crops, is seriously affected by chalkbrood, a larval disease caused by the fungus ascosphaera aggregata. one attempt to control the disease includes removing nests from the nesting boards (the "loose cell" system). we report here that adults emerging from the loose cells are heavily contaminated with a. aggregata spores. the contamination levels are not as high as previously reported for bees emerging directly from the bo ... | 2005 | 16087003 |
| lipids stimulate spore germination in the entomopathogenic ascomycete ascosphaera aggregata. | the alfalfa leafcutting bee (megachile rotundata) is solitary and managed on a large scale for pollination of alfalfa seed crops. the bees nest in holes drilled in wood or polystyrene blocks, and their larvae are highly prone to a fungal disease called chalkbrood. the most prevalent form of chalkbrood is caused by ascosphaera aggregata, but this ascomycete is difficult to culture. hyphae will grow on standard fungal media, but spore germination is difficult to achieve and highly variable. we fou ... | 2004 | 15645171 |
| comparative toxicity and hazards of pesticides to apis and non-apis bees. a chemometrical study. | the adverse effects of 158 pesticides to the honey bee (apis mellifera), the alfalfa leafcutting bee (megachile rotundata) and the alkali bee (nomia melanderi) were compared by means of various linear and non-linear multivariate analyses. a comparison exercise including the bumble bee (bombus spp.) was also performed from a more restricted set of 32 pesticides. while no difference of sensitivity was found between a. mellifera and bombus spp., m. rotundata appeared the most susceptible to pestici ... | 2006 | 14758982 |
| use of rapd analyses to estimate population genetic parameters in the alfalfa leaf-cutting bee, megachile rotundata. | rapd analyses were performed on five geographically isolated populations of megachile rotundata. we used haploid males of the alfalfa leaf-cutting bee, m. rotundata, to overcome the limitation of the dominance of rapd markers in the determination of population genetic parameters. sixteen primers gave rise to 130 polymorphic and 31 monomorphic bands. the unbiased estimators calculated in this study include within- and between-population heterozygosity, nucleotide divergence, and genetic distance. ... | 1996 | 18469925 |
| use of rapd analysis for in situ identification of ascosphaera aggregata and ascosphaera larvis in larval cadavers of the alfalfa leafcutting bee, megachile rotundata. | chalkbrood of the alfalfa leafcutting bee, megachile rotundata, is caused by the fungus ascosphaera aggregata. we used random amplified polymorphic dna (rapd) analysis for the in situ identification of a. aggregata and a related species, ascosphaera larvis, in larval cadavers of m. rotundata. a simple dna extraction method was developed to preferentially isolate dna from fungal spores on the cadaver surface, or from ascocysts beneath the cuticle. similar banding patterns were obtained in a. aggr ... | 1996 | 8683161 |
| p-nitrophenylacetate hydrolysis by honey bee esterases: kinetics and inhibition. | 1. the kinetics and inhibition of p-nitrophenylacetate hydrolysis by cytosolic esterases of 1-day old female honey bees, apis mellifera l., were studied. 2. the calculated values obtained were km = 2.27 x 10(-5)m and vmax = 2.48 x 10(-8) mol/s per mg protein. 3. the inhibition mechanisms examined for four organophosphorus insecticides were highly competitive in nature and based on competitive inhibition coefficients the order of toxicity was naled > dichlorvos > cis-mevinphos = trans-mevinphos. ... | 1993 | 8498090 |
| esterase isozymes in a solitary bee, megachile rotundata (fab.): characterization, developmental multiplicity, and adult variability. | this study describes the biochemical characterization and genetic variation of cytosolic esterases in the alfalfa leafcutting bee, megachile rotundata (fab.). esterase isozymes were separated by nondenaturing polyacrylamide gel electrophoresis and isoelectric focusing and characterized by inhibition with eserine sulfate, edta, paraoxon, and p-hydroxymercuribenzoate. based on inhibition patterns and substrate specificity, there are major differences between adults and immature forms and more subt ... | 1990 | 2125203 |
| the kinetics and inhibition of p-nitrophenylacetate-hydrolysing esterases in a solitary bee, megachile rotundata (fab.). | 1. the kinetics and inhibition of p-nitrophenylacetate hydrolysis by cytosolic esterases of female alfalfa leafcutting bees, megachile rotundata (fab.) was examined. 2. for p-nitrophenylacetate, the km = 1.24 x 10(-4) m and vmax = 2.29 x 10(-9) mol/s per mg protein. 3. regarding four organophosphate insecticides, the mechanism of inhibition in all cases was mixed (competitive and uncompetitive) and, based on inhibition constants, the order of toxicity was naled greater than paraoxon greater than ... | 1990 | 2349807 |
| spore load of ascosphaera species on emerging adults of the alfalfa leafcutting bee, megachile rotundata. | the spore load of ascosphaera species spores on larval chalkbrood cadavers and newly emergent adults of the alfalfa leafcutting bee, megachile rotundata, was determined. the spore content of chalkbrood cadavers ranged from 3 x 10 to 5 x 10. adults emerging through zero to nine cadavers carried spores on all body parts examined by scanning electron microscopy. estimates of the total number of spores obtained from a series of adult washes ranged from 9 x 10 to 8 x 10. some adult males which emerge ... | 1980 | 16345532 |
| pesticides and honey bees: nectar and pollen contamination in alfalfa treated with dimethoate. | medicago sativa l. (leguminosae) sprayed with o,o-dimethyl s-(n-methylcarbamoylmethyl) phosphorodithioate (dimethoate) had only 0.5 ppm of dimethoate in pollen one day later, but 3 ppm in nectar one week later, and 1 ppm in nectar two weeks later. as little as 1 ppm added to syrup fed to caged workers of apis mellifera l. (apidae) inhibited cholinesterase and reduced survival. bees given a choice between treated and untreated syrups showed no preference; this suggests that the levels of dimethoa ... | 1980 | 7387183 |
| sex control by bees: a voluntary act of egg fertilization during oviposition. | the alfalfa leaf-cutter bee, megachile rotundata, stops abdominal contractions briefly during oviposition of female eggs but not during oviposition of male eggs. sperm stored in the spermatheca probably is pumped onto the micropyle of the egg during this pause. the stimulus inducing fertilization seems to be associated with the depth of the nesting tunnel. | 1970 | 5409486 |
| induction of somatic embryogenesis using side chain and ring modified forms of phenoxy acid growth regulators. | the induction of somatic embryo development in cell cultures of alfalfa (medicago sativa), celery (apium graveolens), and lettuce (lactuca sativa) was compared for 2,4-dichlorophenoxy-acetic acid (2,4-d) and various phenoxy acid growth regulators. tests using a series of straight chain extensions to the phenoxy acid side chain indicate that phenoxybutanoic acid is active, whereas the phenoxypropanoic and phenoxypentanoic analogs are inactive for the induction of alfalfa embryogenesis. side branc ... | 1992 | 16668836 |
| rodent food quality and its relation to crops and other environmental and population parameters in an agricultural landscape. | the diet, its quality and quantity considerably influence population parameters of rodents. in this study, we used nirs methods for estimation of nitrogen content in stomachs of rodent populations. the study was carried out in diverse arable landscape in south moravia, czech republic. rodents were sampled in cultural crops (alfalfa, barley, wheat, sunflower, maize and rape) as well as in fallow habitats (herbal set-aside and old orchard). influence of habitat, date, year, individual parameters ( ... | 2016 | 27099997 |
| cell wall proteome analysis of arabidopsis thaliana mature stems. | plant stems carry flowers necessary for species propagation and need to be adapted to mechanical disturbance and environmental factors. the stem cell walls are different from other organs and can modify their rigidity or viscoelastic properties for the integrity and the robustness required to withstand mechanical impacts and environmental stresses. plant cell wall is composed of complex polysaccharide networks also containing cell wall proteins (cwps) crucial to perceive and limit the environmen ... | 2017 | 28155257 |
| comparative transcriptome investigation of global gene expression changes caused by mir156 overexpression in medicago sativa. | medicago sativa (alfalfa) is a low-input forage and potential bioenergy crop, and improving its yield and quality has always been a focus of the alfalfa breeding industry. transgenic alfalfa plants overexpressing a precursor of alfalfa microrna156 (msmir156) were recently generated by our group. these plants (mir156oe) showed enhanced biomass yield, reduced internodal length, increased shoot branching and trichome density, and a delay in flowering time. transcripts of three squamosa-promoter bin ... | 2016 | 27542359 |
| expression of an alfalfa (medicago sativa l.) peroxidase gene in transgenic arabidopsis thaliana enhances resistance to nacl and h2o2. | peroxidases (pods) are enzymes that play important roles in catalyzing the reduction of h2o2 and the oxidation of various substrates. they function in many different and important biological processes, such as defense mechanisms, immune responses, and pathogeny. the pod genes have been cloned and identified in many plants, but their function in alfalfa (medicago sativa l.) is not known, to date. based on the pod gene sequence (genbank accession no. l36157.1), we cloned the pod gene in alfalfa, w ... | 2016 | 27323080 |
| mrna biogenesis-related helicase eif4aiii from arabidopsis thaliana is an important factor for abiotic stress adaptation. | similar to other plant species, arabidopsis has a huge repertoire of predicted helicases, including the eif4aiii factor, a putative component of the exon junction complex related to mrna biogenesis. in this article, we integrated evolutionary and functional approaches to have a better understanding of eif4aiii function in plants. phylogenetic analysis showed that the mrna biogenesis-related helicase eif4aiii is the ortholog of the stress-related helicases pdh45 from pisum sativum and mh1 from me ... | 2016 | 26883227 |
| eukaryotic hsp70 chaperones in the intermembrane space of chloroplasts. | multiple eukaryotic hsp70 typically localized in the cytoplasm are also distributed to the intermembrane space of chloroplasts and might thereby represent the missing link in energizing protein translocation. protein translocation into organelles is a central cellular process that is tightly regulated. it depends on signals within the preprotein and on molecular machines catalyzing the process. molecular chaperones participate in transport and translocation of preproteins into organelles to cont ... | 2016 | 26669598 |
| monitoring protein phosphorylation by acrylamide pendant phos-tag™ in various plants. | the aim of the present study is to rationalize acrylamide pendant phos-tag™ in-gel discrimination of phosphorylated and non-phosphorylated plant protein species with standard immunoblot analysis, and optimize sample preparation, efficient electrophoretic separation and transfer. we tested variants of the method including extraction buffers suitable for preservation of phosphorylated protein species in crude extracts from plants and we addressed the importance of the cation (mn(2+) or zn(2+)) use ... | 2015 | 26029234 |
| assessment of heat shock protein 70 induction by heat in alfalfa varieties and constitutive overexpression in transgenic plants. | heat shock proteins (hsps) are molecular chaperones involved in many cellular functions. it has been shown that mammalian cytosolic hsp70 binds antigenic peptides mediating the activation of the immune system, and that it plays a determining role in tumour immunogenicity. this suggests that hsp70 may be used for the production of conjugated vaccines. human and plant hsps share high sequence similarity and some important biological functions in vitro. in addition, plant hsps have no endotoxic sid ... | 2015 | 25951604 |
| molecular and biochemical analysis of chalcone synthase from freesia hybrid in flavonoid biosynthetic pathway. | chalcone synthase (chs) catalyzes the first committed step in the flavonoid biosynthetic pathway. in this study, the cdna (fhchs1) encoding chs from freesia hybrida was successfully isolated and analyzed. multiple sequence alignments showed that both the conserved chs active site residues and chs signature sequence were found in the deduced amino acid sequence of fhchs1. meanwhile, crystallographic analysis revealed that protein structure of fhchs1 is highly similar to that of alfalfa chs2, and ... | 2015 | 25742495 |
| advances in the understanding of cuticular waxes in arabidopsis thaliana and crop species. | the aerial parts of plants are covered with a cuticle, a hydrophobic layer consisting of cutin polyester and cuticular waxes that protects them from various environmental stresses. cuticular waxes mainly comprise very long chain fatty acids and their derivatives such as aldehydes, alkanes, secondary alcohols, ketones, primary alcohols, and wax esters that are also important raw materials for the production of lubricants, adhesives, cosmetics, and biofuels. the major function of cuticular waxes i ... | 2015 | 25693495 |
| application of two-spotted spider mite tetranychus urticae for plant-pest interaction studies. | the two-spotted spider mite, tetranychus urticae, is a ubiquitous polyphagous arthropod herbivore that feeds on a remarkably broad array of species, with more than 150 of economic value. it is a major pest of greenhouse crops, especially in solanaceae and cucurbitaceae (e.g., tomatoes, eggplants, peppers, cucumbers, zucchini) and greenhouse ornamentals (e.g., roses, chrysanthemum, carnations), annual field crops (such as maize, cotton, soybean, and sugar beet), and in perennial cultures (alfalfa ... | 2014 | 25046103 |
| investigating the toxicity, uptake, nanoparticle formation and genetic response of plants to gold. | we have studied the physiological and genetic responses of arabidopsis thaliana l. (arabidopsis) to gold. the root lengths of arabidopsis seedlings grown on nutrient agar plates containing 100 mg/l gold were reduced by 75%. oxidized gold was subsequently found in roots and shoots of these plants, but gold nanoparticles (reduced gold) were only observed in the root tissues. we used a microarray-based study to monitor the expression of candidate genes involved in metal uptake and transport in arab ... | 2014 | 24736522 |
| characterization of the β-1,3-glucanase gene in peanut (arachis hypogaea l.) by cloning and genetic transformation. | plant β-1,3-glucanases are commonly involved in disease resistance. this report describes the cloning and genetic transformation of a β-1,3-glucanase gene from peanut. the gene was isolated from both the genomic dna and cdna of peanut variety huayu20 by polymerase chain reaction (pcr) and reverse transcription pcr (rt-pcr), respectively. the dna sequence contained 1471 bp including two exons and one intron, and the coding sequence contained 1047 bp that coded for a 348-amino acid protein with a ... | 2014 | 24668677 |
| early transcriptional responses to mercury: a role for ethylene in mercury-induced stress. | understanding the cellular mechanisms of plant tolerance to mercury (hg) is important for developing phytoremediation strategies of hg-contaminated soils. the early responses of alfalfa (medicago sativa) seedlings to hg were studied using transcriptomics analysis. a medicago truncatula microarray was hybridized with high-quality root rna from m. sativa treated with 3 μm hg for 3, 6 and 24 h. the transcriptional pattern data were complementary to the measurements of root growth inhibition, lipid ... | 2014 | 24033367 |
| molecular evolutionary analysis of the alfin-like protein family in arabidopsis lyrata, arabidopsis thaliana, and thellungiella halophila. | in previous studies, the alfin1 gene, a transcription factor, enhanced salt tolerance in alfalfa, primarily through altering gene expression levels in the root. here, we examined the molecular evolution of the alfin-like (al) proteins in two arabidopsis species (a. lyrata and a. thaliana) and a salt-tolerant close relative thellungiella halophila. these al-like proteins could be divided into four groups and the two known duf3594 and phd-finger domains had co-evolved within each group of genes, i ... | 2013 | 23840867 |
| defining the core proteome of the chloroplast envelope membranes. | high-throughput protein localization studies require multiple strategies. mass spectrometric analysis of defined cellular fractions is one of the complementary approaches to a diverse array of cell biological methods. in recent years, the protein content of different cellular (sub-)compartments was approached. despite of all the efforts made, the analysis of membrane fractions remains difficult, in that the dissection of the proteomes of the envelope membranes of chloroplasts or mitochondria is ... | 2013 | 23390424 |
| expression of the alfalfa frigida-like gene, msfri-l delays flowering time in transgenic arabidopsis thaliana. | in arabidopsis, allelic variation at the frigida (fri) locus is a major determinant of natural variation in flowering time. we have identified a frigida like protein gene, msfri-l, with unknown function from medicago sativa l. expression of msfri-l was increased in wild alfalfa under continuous cold conditions and the gene was expressed in all tissues including roots, stems, leaves and flowers, and weakest in flowers under light/dark conditions. expression of msfri-l in transgenic arabidopsis pl ... | 2013 | 23212611 |
| salicylic acid mediates the reduced growth of lignin down-regulated plants. | down-regulation of the enzyme hydroxycinnamoyl coa: shikimate hydroxycinnamoyl transferase (hct) in thale cress (arabidopsis thaliana) and alfalfa (medicago sativa) leads to strongly reduced lignin levels, reduced recalcitrance of cell walls to sugar release, but severe stunting of the plants. levels of the stress hormone salicylic acid (sa) are inversely proportional to lignin levels and growth in a series of transgenic alfalfa plants in which lignin biosynthesis has been perturbed at different ... | 2011 | 22123972 |
| survey and characterization of nbs-lrr (r) genes in curcuma longa transcriptome. | resistance genes are among the most important gene classes for plant breeding purposes being responsible for activation of plant defense mechanisms. among them, the nucleotide binding site-leucine rich repeat (nbs-lrr) class r-genes are the most abundant and actively found in all types of plants. insilico characterization of est database resulted in the detection of 28 nbs types r-gene sequences in curcuma longa. all the 28 sequences represented the nb-arc domain, 21 of which were found to have ... | 2011 | 21814396 |
| effects of selenium hyperaccumulation on plant-plant interactions: evidence for elemental allelopathy? | • few studies have investigated plant-plant interactions involving hyperaccumulator plants. here, we investigated the effect of selenium (se) hyperaccumulation on neighboring plants. • soil and litter se concentrations were determined around the hyperaccumulators astragalus bisulcatus and stanleya pinnata and around the nonhyperaccumulators medicago sativa and helianthus pumilus. we also compared surrounding vegetative cover, species composition and se concentration in two plant species (artemis ... | 2011 | 21371042 |
| complexation of hg with phytochelatins is important for plant hg tolerance. | three-week-old alfalfa (medicago sativa), barley (hordeum vulgare) and maize (zea mays) were exposed for 7 d to 30 µm of mercury (hgcl(2) ) to characterize the hg speciation in root, with no symptoms of being poisoned. the largest pool (99%) was associated with the particulate fraction, whereas the soluble fraction (sf) accounted for a minor proportion (<1%). liquid chromatography coupled with electro-spray/time of flight mass spectrometry showed that hg was bound to an array of phytochelatins ( ... | 2011 | 21276009 |
| an nac transcription factor orchestrates multiple features of cell wall development in medicago truncatula. | to identify genes controlling secondary cell wall biosynthesis in the model legume medicago truncatula, we screened a tnt1 retrotransposon insertion mutant population for plants with altered patterns of lignin autofluorescence. from more than 9000 r1 plants screened, four independent lines were identified with a total lack of lignin in the interfascicular region. the mutants also showed loss of lignin in phloem fibers, reduced lignin in vascular elements, failure in anther dehiscence and absence ... | 2010 | 20408998 |
| isolation of genes from female sterile flowers in medicago sativa. | a better knowledge of female sporogenesis and gametogenesis could have several practical applications, from commercial hybrid seed production to gene containment in gm crops. with the purpose of isolating genes involved in the megasporogenesis process, the cdna-aflp technique was employed to isolate transcript-derived fragments (tdf) differentially expressed between female-fertile and female-sterile full-sib alfalfa plants. this female sterility trait involves female-specific arrest of sporogene ... | 2009 | 20033460 |
| rapid quantification of global dna methylation by isocratic cation exchange high-performance liquid chromatography. | the dna of many eukaryotes is methylated at specific cytosine residues in connection with gene regulation. here we report a method for the quantification of global cytosine methylation based on enzymatic hydrolysis of dna, dephosphorylation, and subsequent high-performance cation exchange chromatography. nucleosides are separated in less than 3 min under isocratic conditions on a benzenesulfonic acid-modified silica phase and detected by uv absorption. as little as 1 microg of dna is sufficient ... | 2008 | 18249178 |
| non-invasive microscopy of tip-growing root hairs as a tool for study of dynamic and cytoskeleton-based vesicle trafficking. | the techniques of live cell imaging by electronic light microscopy and confocal microscopy were used to analyse the cytoarchitecture, organelle dynamics and membrane trafficking in living root hairs of arabidopsis thaliana and medicago sativa. we focused on the motility of vesicles in the tip of growing root hairs, the internalisation of plasma membrane by endocytosis and the fate of endocytic compartments. vesicles as well as their trafficking to and contact with the plasma membrane were visual ... | 2008 | 18158257 |
| isolation and characterization of class a4 heat shock transcription factor from alfalfa. | plant heat shock transcription factors (hsfs) regulate transcription of heat shock (hs) genes. in arabidopsis thaliana, 21 hsfs have been classified into groups a-c. members of class a act as typical transcriptional activators, whereas b hsfs function as coactivators or repressors depending on promoter context. the function of class c hsfs is still unclear. here, we present the isolation and characterization of the first hsf from alfalfa (medicago sativa l.) and designate it mshsfa4 based on ami ... | 2006 | 22980202 |
| significant microsynteny with new evolutionary highlights is detected between arabidopsis and legume model plants despite the lack of macrosynteny. | the increased amount of data produced by large genome sequencing projects allows scientists to carry out important syntenic studies to a great extent. detailed genetic maps and entirely or partially sequenced genomes are compared, and macro- and microsyntenic relations can be determined for different species. in our study, the syntenic relationships between key legume plants and two model plants, arabidopsis thaliana and populus trichocarpa were investigated. the comparison of the map position o ... | 2005 | 16273388 |
| cloning and expression analysis of a vacuolar na+/h+ antiporter gene from alfalfa. | a full-length cdna, named msnhx1, encoding a vacuolar na+/h+ antiporter was cloned from alfalfa (medicago sativa), using degenerate primers, followed by 3' and 5' race. the cdna sequence was 2225 bp long and included an open reading frame encoding a deduced protein of 541-amino-acid polypeptide. the deduced amino acid sequence showed high similarity (more than 73%) to those of the previously cloned na+/h+ antiporters form arabidopsis thaliana, qryza sativa, atriplex gemlinin, beta vulgaris and h ... | 2005 | 16243725 |
| calcium/calmodulin up-regulates a cytoplasmic receptor-like kinase in plants. | calcium/calmodulin-dependent kinases play an important role in protein phosphorylation in eukaryotes. however, not much is known about calcium/calmodulin-dependent protein phosphorylation and its role in signal transduction in plants. by using a protein-protein interaction-based approach, we have isolated a novel plant-specific calmodulin-binding receptor-like cytoplasmic kinase (crck1) from arabidopsis thaliana, as well as its ortholog from medicago sativa (alfalfa). crck1 does not show high ho ... | 2004 | 15292241 |
| new perspectives on proanthocyanidin biochemistry and molecular regulation. | our understanding of proanthocyanidin (syn. condensed tannin) synthesis has been recently extended by substantial developments concerning both structural and regulatory genes. a gene encoding leucoanthocyanidin reductase has been obtained from the tropical forage, desmodium uncinatum, with the latter enzyme catalyzing formation of (+)-catechin. the banyuls gene in arabidopsis thaliana, previously proposed to encode leucoanthocyanidin reductase or to regulate proanthocyanidin biosynthesis, has be ... | 2003 | 12943753 |
| a soybean plastid-targeted nadh-malate dehydrogenase: cloning and expression analyses. | a typical soybean (glycine max) plant assimilates nitrogen rapidly both in active root nodules and in developing seeds and pods. oxaloacetate and 2-ketoglutarate are major acceptors of ammonia during rapid nitrogen assimilation. oxaloacetate can be derived from the tricarboxylic acid (tca) cycle, and it also can be synthesized from phosphoenolpyruvate and carbon dioxide by phosphoenolpyruvate carboxylase. an active malate dehydrogenase is required to facilitate carbon flow from phosphoenolpyruva ... | 2001 | 21669645 |
| isolation and characterization of two different cdnas of delta1-pyrroline-5-carboxylate synthase in alfalfa, transcriptionally induced upon salt stress. | two different cdna clones, msp5cs-1 and msp5cs-2, encoding delta1 -pyrroline-5-carboxylate synthase (p5cs). the first enzyme of the proline biosynthetic pathway, were isolated from a lambdazap-cdna library constructed from salt stressed medicago sativa roots. msp5cs-1 (2.6 kb) has an open reading frame of 717 amino acids, as well as a non-spliced intron at a position corresponding to the evolutionary fusion point of the bacterial proa and prob genes. msp5cs-2 (1.25 kb) is a partial clone. the cl ... | 1998 | 9862493 |
| plant cdc2 is not only targeted to the pre-prophase band, but also co-localizes with the spindle, phragmoplast, and chromosomes. | a polyclonal antiserum against the p34cdc2 homologue of arabidopsis thaliana, cdc2aat, was used in parallel with a polyclonal antiserum against the pstaire motif to study the subcellular localization of cdc2 during the cell cycle of isolated root tip cells of medicago sativa. during interphase, cdc2 was located in the nucleus and in the cytoplasm. the cytoplasmic localization persisted during the complete cell cycle, whereas the nuclear signal disappeared at nuclear envelope breakdown. at the be ... | 1997 | 9428718 |
| a wound- and methyl jasmonate-inducible transcript coding for a myrosinase-associated protein with similarities to an early nodulin. | myrosinase is regarded as a defense-related enzyme in the brassicaceae and is capable of hydrolyzing glucosinolates into various compounds, some of which are toxic. several myrosinase isoenzymes exist, and some of them have been found in association with nonmyrosinase proteins. one of these associated proteins, myrosinase-associated protein (myap), was purified from seeds of brassica napus both in complexes with myrosinase and in a free form. myap is a glycosylated, 40-kd protein with at least o ... | 1996 | 8742330 |
| rhizobium anhuiense sp. nov., isolated from effective nodules of vicia faba and pisum sativum. | four rhizobia-like strains, isolated from root nodules of pisum sativum and vicia faba grown in anhui and jiangxi provinces of china, were grouped into the genus rhizobium but were distinct from all recognized species of the genus rhizobium by phylogenetic analysis of 16s rrna and housekeeping genes. the combined sequences of the housekeeping genes atpd, reca and glnii for strain ccbau 23252(t) showed 86.9 to 95% similarity to those of known species of the genus rhizobium. all four strains had n ... | 2015 | 26025940 |
| milk production performance of friesian-holstein cows fed diets containing medicago sativa, centrosema pubescens, or groundnut haulms (arachis hypogaea). | to investigate the effect of feeding dairy cows diets containing lucerne hay, centrosema hay, and groundnut haulms (crop residue) on dry matter intake (dmi), milk yield, and milk composition, nine multiparous friesian-holstein cows in their mid-lactation stage were used in a 3 × 3 crossover design replicated three times. dairy cows fed lucerne hay had significantly (p < 0.001) higher dmi than dairy cows fed centrosema hay. dmi for cows fed groundnut haulms and lucerne hay was not significantly d ... | 2013 | 23460085 |
| threecornered alfalfa hopper (hemiptera: membracidae): seasonal occurrence, girdle distribution, and response to insecticide treatment on peanut in south carolina. | a survey of threecornered alfalfa hopper, spissistilus festinus (say) (hemiptera: membracidae), damage in 60 south carolina peanut, arachis hypogaea l., fields showed that 89 and 58% of plants had feeding girdles during 2003 and 2004, respectively. use of a foliar insecticide for other target pests reduced hopper damage. hopper damage was not affected by sampling distance from the field edge; therefore, injury was adequately assessed at 10 m from field borders. in-furrow insecticide choice, plan ... | 2007 | 17849875 |
| influence of the size of indigenous rhizobial populations on establishment and symbiotic performance of introduced rhizobia on field-grown legumes. | indigenous rhizobia in soil present a competition barrier to the establishment of inoculant strains, possibly leading to inoculation failure. in this study, we used the natural diversity of rhizobial species and numbers in our fields to define, in quantitative terms, the relationship between indigenous rhizobial populations and inoculation response. eight standardized inoculation trials were conducted at five well-characterized field sites on the island of maui, hawaii. soil rhizobial population ... | 1991 | 16348393 |
| n abundance of nodules as an indicator of n metabolism in n(2)-fixing plants. | this paper expands upon previous reports of (15)n elevation in nodules (compared to other tissues) of n(2)-fixing plants. n(2)-fixing nodules of glycine max (soybeans), vigna unguiculata (cowpea), phaseolus vulgaris (common bean), phaseolus coccineus (scarlet runner bean), prosopis glandulosa (mesquite), and olneya tesota (desert ironwood) were enriched in (15)n. nodules of vicia faba (fava beans), arachis hypogaea (peanut), trifolium pratense (red clover), pisum sativum (pea), lathyrus sativus ... | 1982 | 16662517 |
| the nucleotide sequence of a nodule-specific gene, nms-25 of medicago sativa: its primary evolution via exon-shuffling and retrotransposon-mediated dna rearrangements. | we present the primary structure of a nodule-specific gene, nms-25 from medicago sativa l. cultivar nagyszénási. analysis of the nucleotide sequence of nms-25 revealed that this gene shows all the characteristics of an interrupted plant gene consisting of 13 exons and 12 introns. the promoter region of nms-25 contains the common promoter elements of plant genes as well as motifs which are supposed to be involved in nodule-specific expression. there are two exon-like sequences in the gene named p ... | 1990 | 1966488 |
| sequence analysis and homology modeling of peroxidase from medicago sativa. | plant peroxidases are one of the most extensively studied group of enzymes which find applications in the environment, health, pharmaceutical, chemical and biotechnological processes. class iii secretary peroxidase from alfalfa (medicago sativa) has been characterized using bioinformatics approach physiochemical properties and topology of alfalfa peroxidase were compared with that of soybean and horseradish peroxidase, two most popular commercially available peroxidase preparations. lower value ... | 2012 | 23275690 |
| anthropogenic islands in the arid west: comparing the richness and diversity of insect communities in cultivated fields and neighboring wildlands. | the interface between cultivated fields and wildlands has become a central focus for conservation biology, particularly as previously uncultivated lands worldwide are converted to agriculture at an escalating pace. although research in some parts of the world has highlighted the potential value of agricultural lands for managing and preserving native animals, we know comparatively little about native animals spanning the cultivated/wildlands interface in north america. the study reported here in ... | 2009 | 19689881 |
| influence of sagebrush terpenoids on mule deer preference. | the effect on mule deer (odocoileus hemionus hemionus rafinesque) preference of compounds in mountain big sagebrush [artemisia tridentata nutt. ssp.vaseyana (rydb.) beetle], wyoming big sagebrush (a. t. ssp.wyomingensis beetle and young), basin big sagebrush (a. t. ssp.tridentata), and black sagebrush (a. nova nels.) was compared using a two-choice preference test. compounds tested included:p-cymene, 1,8-cineole, methacrolein (two concentrations), and the nonvolatile crude terpenoid fraction (nv ... | 1991 | 24258589 |
| from soil to leaves--aluminum fractionation by single step extraction procedures in polluted and protected areas. | the paper presents the fractionation of aluminum in the samples of soil and plants of different species using a selective single-step extraction method. the study was conducted in the area located near a chemical plant, which for many years served as a post-crystallization leachate disposal site storing chemical waste (sector i), and in the area around the site: in wielkopolski national park, rogalin landscape park and toward the infiltration ponds at the "dębina" groundwater well-field for the ... | 2013 | 23651943 |
| asparagus decline: autotoxicity and autotoxic compounds in asparagus rhizomes. | asparagus (asparagus officinalis l.) is a perennial vegetable, but its crop productivity and quality decrease gradually. one possible reason for "asparagus decline" is thought to be the autotoxicity of asparagus. however, the autotoxic property of asparagus rhizomes remains unknown. the objective of this study was to determine the potential role of rhizomes in the autotoxicity of asparagus. an aqueous methanol extract of asparagus rhizomes inhibited the growth of asparagus seedlings and six othe ... | 2017 | 28314158 |
| assessment of in vitro digestibility and fermentation parameters of alfalfa hay-based diet following direct incorporation of fenugreek seed (trigonella foenum) and asparagus root (asparagus officinalis). | this study was completed to evaluate the effect of fenugreek seed (trigonella foenum; fs) and asparagus root (asparagus officinalis; ar) on in vitro nutrient digestibility and fermentation patterns. different levels [0%, 5%, 10%, 15% and 20% of dry matter (dm)] of the medicinal plants were included using alfalfa hay (ah) as a basal substrate at different incubation times (12, 18, 24 and 48 h). total phenolic components of ah, fs and ar were 5.9, 10 and 8.3 g/kg dm, whereas total tannins were 0.4 ... | 2013 | 22741923 |
| identification and characterization of an mrna encoding a proline-rich protein that rapidly declines in abundance in the tips of harvested asparagus spears. | we previously isolated a cdna clone, ptip13, whose homologous mrna rapidly declined in abundance in the tips of harvested asparagus (asparagus officinalis l.) spears [king and davies (1992) plant physiol. 100: 1661]. in order to identify factors regulating the postharvest deterioration of asparagus, we have now sequenced the ptip13 cdna, derived the encoded amino acid sequence and determined the cellular location of ptip13 mrna by in situ hybridization. ptip13 encodes a derived protein that is r ... | 1996 | 8819317 |
| differential effects of legume species on the recovery of soil microbial communities, and carbon and nitrogen contents, in abandoned fields of the loess plateau, china. | plant-soil interactions are known to influence a wide range of ecosystem-level functions. moreover, the recovery of these functions is of importance for the successful restoration of soils that have been degraded through intensive and/or inappropriate land use. here, we assessed the effect of planting treatments commonly used to accelerate rates of grassland restoration, namely introduction of different legume species medicago sativa, astragalus adsurgens, melilotus suaveolens, on the recovery o ... | 2012 | 23064665 |
| [comparison of ecophysiological characteristics of seven plant species in semiarid loess hilly-gully region]. | the diurnal course of photosynthetic rate, transpiration rate, and leaf water potential (psi l) of five plant species in north shaanxi loess hilly-gully region were measured in dry seasons. based on the daily maximum photosynthetic and transpiration rates, daily total assimilation and transpiration, and diurnal change characteristics of psi l, the test plants were classified into different eco-adaptation types. panicum virgatum l. had high photosynthetic rate, low transpiration rate and high wat ... | 2007 | 17650846 |
| [responses of medicago sativa and astragalus adsurgens seedlings growth and water use to soil moisture regime]. | in the semi-arid area of loess plateau, seasonal drought often occurs during the vegetative stage of grass plants, leading to the subsequent serious reduction of their yield. aimed to study the responses of the seedlings growth and water use of two perennial leguminous grasses medicago sativa and astragalus adsurgens to different soil moisture regimes, a pot experiment was installed with five treatments, i.e., adequate water supply (hw), moderate water stress (lw), soil drying gradually from hw ... | 2005 | 16515181 |
| selenium hyperaccumulation reduces plant arthropod loads in the field. | the elemental defense hypothesis proposes that some plants hyperaccumulate toxic elements as a defense mechanism. in this study the effectiveness of selenium (se) as an arthropod deterrent was investigated under field conditions. arthropod loads were measured over two growing seasons in se hyperaccumulator habitats in colorado, usa, comparing se hyperaccumulator species (astragalus bisulcatus and stanleya pinnata) with nonhyperaccumulators (camelina microcarpa, astragalus americanus, descurainia ... | 2008 | 18028291 |
| characterization of a pathogenesis-related class 10 protein (pr-10) from astragalus mongholicus with ribonuclease activity. | a pathogenesis-related (pr) class 10 protein (designated ampr-10) was first isolated from the chinese medicinal material astragalus mongholicus using a combination of affinity chromatography on zn-chelate agarose 4b, ion exchange chromatography on qae sephadex a-25 and gel filtration on sephadex g50. the purified ampr-10 showed a single band with a molecular mass of 17.2kda in sds-page. the molecular mass of intact ampr-10 was determined to be 32.8kda by gel filtration. thus, ampr-10 is a dimeri ... | 2008 | 18024144 |
| host-plant dependent population genetics of the invading weevil hypera postica. | population genetics of invading pests can be informative for understanding their ecology. in this study, we investigated population genetics of the invasive alfalfa weevil hypera postica in fukuoka prefecture, japan. we analyzed mitochondrial trnaleu-coii, nuclear ef-1α gene fragments, and wolbachia infection in relation to three leguminous host plants: vicia angustifolia, vicia villosa, and a new host astragalus sinicus cultivated as a honey source and green manure crop. a parsimony network gen ... | 2015 | 25336385 |
| tillage and residue burning affects weed populations and seed banks. | an integrated weed management approach requires alternative management practices to herbicide use such as tillage, crop rotations and cultural controls to reduce soil weed seed banks. the objective of this study was to examine the value of different tillage practices and stubble burning to exhaust the seed bank of common weeds from the northern grain region of australia. five tillage and burning treatments were incorporated in a field experiment, at armidale (30 degrees 30's, 151 degrees 40'e), ... | 2006 | 17390813 |
| residual soil nitrate content and profitability of five cropping systems in northwest iowa. | many communities in the midwestern united states obtain their drinking water from shallow alluvial wells that are vulnerable to contamination by no3-n from the surrounding agricultural landscape. the objective of this research was to assess cropping systems with the potential to produce a reasonable return for farmers while simultaneously reducing the risk of no3-n movement into these shallow aquifers. from 2009 to 2013 we conducted a field experiment in northwest iowa in which we evaluated five ... | 2017 | 28248976 |
| effect of sewage water on mineral nutritive potential of six fodder species grown under semiarid conditions. | investigation was performed to assess the effect of different sewage water treatments on the metal status of different fodder species consumed by ruminants under semi-arid conditions. five samples each of six fodder species viz., trifolium alexandrinum, cichorium intybus, avena sativa, medicago polymorpha, brassica campestris and medicago sativa were collected from three fields irrigated with canal water, mix water (canal water and sewage water) and sewage water, respectively. fodder samples wer ... | 2011 | 23961142 |
| nitrogen fertilizer effects on soil carbon balances in midwestern u.s. agricultural systems. | a single ecosystem dominates the midwestern united states, occupying 26 million hectares in five states alone: the corn-soybean agroecosystem [zea mays l.-glycine max (l.) merr.]. nitrogen (n) fertilization could influence the soil carbon (c) balance in this system because the corn phase is fertilized in 97-100% of farms, at an average rate of 135 kg n x ha(-1) x yr(-1). we evaluated the impacts on two major processes that determine the soil c balance, the rates of organic-carbon (oc) inputs and ... | 2009 | 19688919 |
| influence of crop residues on trifluralin mineralization in a silty clay loam soil. | trifluralin is typically applied onto crop residues (trash, stubble) at the soil surface, or onto the bare soil surface after the incorporation of crop residues into the soil. the objective of this study was to quantify the effect of the type and amount of crop residues in soil on trifluralin mineralization in a wellwood silty clay loam soil. leaves and stubble of potato (solanum tuberosum) (p); canola (brassica napus) (c), wheat (triticum aestivum) (w), oats (avena sativa), (o), and alfalfa (me ... | 2015 | 17454379 |
| forage fibre digestion, rates of feed passage and gut fill in juvenile and adult red kangaroos macropus rufus desmarest: why body size matters. | using red kangaroos macropus rufus desmarest, a large (>20 kg) marsupial herbivore, we compared the digestive capabilities of juveniles with those of mature, non-lactating females on high-quality forage (chopped lucerne medicago sativa hay) of 43+/-1% neutral-detergent fibre (ndf) and poorer quality, high-fibre forage (chopped oaten avena sativa hay) of 64+/-1% ndf. on chopped lucerne apparent dry matter (dm) digestibilities by young-at-foot (yaf) red kangaroos (an age that would normally be tak ... | 2006 | 16574810 |
| endogenous nitrogen excretion by red kangaroos (macropus rufus): effects of animal age and forage quality. | red kangaroos (macropus rufus) are large (>20 kg) herbivorous marsupials common to arid and semiarid australia. the population dynamics of red kangaroos are linked with environmental factors, operating largely through juvenile survival. a crucial period is the young-at-foot (yaf) stage, when juveniles have permanently left the mother's pouch but still take milk from a teat in the pouch. forage quantity and quality have been implicated in drought-related mortalities of juvenile kangaroos. here we ... | 2013 | 16555200 |
| ovarian development and ovipositional preference of the western corn rootworm (coleoptera: chrysomelidae) variant in east central illinois. | the rotation of maize, zea mays l., and soybean, glycine max (l.) merr., has been the traditional cultural tactic to manage the western corn rootworm, diabrotica virgifera virgifera leconte, in the corn belt. the reduced effectiveness of this rotation as a pest management tool in east central illinois, northern indiana, and southern michigan can be explained by the shift in the ovipositional behavior of the new variant of western corn rootworm. the objective of this study was to evaluate the inf ... | 2004 | 15154460 |
| captures of western corn rootworm (coleoptera: chrysomelidae) adults with pherocon am and vial traps in four crops in east central illinois. | it is hypothesized that the long-term rotation of maize (zea mays l.) and soybean (glycine max l.) in east central illinois has caused a significant change in the ovipositional behavior of the western corn rootworm, diabrotica virgifera virgifera leconte. since the mid 1990s in east central illinois, western corn rootworm adults have been observed feeding on soybean foliage and also now use soybean fields as egg laying sites. this behavioral adaptation has greatly decreased the effectiveness of ... | 2003 | 12852611 |
| crop rotation impacts on potato protein. | the impact of nitrogen (n) fertilization on potato (solanum tuberosum l.) protein yield and nutritional quality is well documented but of little benefit to growers with limited access to fertilizer or capital (e.g. in lesser developed countries). this study was conducted 1) to evaluate the extent which crude protein yield in potatoes can be influenced by crop rotation with no n fertilizer and 2) to determine if crop rotation and minimal application of n fertilizer can meet the total protein yiel ... | 1998 | 10426115 |
| elimination of the adverse effects of urea fertilizer on seed germination, seedling growth, and early plant growth in soil. | the rapidly increasing importance of urea fertilizer in world agriculture has stimulated research to find methods of reducing the problems associated with the use of this fertilizer. one of these problems is that urea has adverse effects on seed germination, seedling growth, and early plant growth in soil. because there is evidence that these adverse effects are caused largely, if not entirely, by ammonia produced through hydrolysis of urea fertilizer by soil urease, we explored the possibility ... | 1988 | 16593951 |