| changes in heat production by mature cows after changes in feeding level. | we hypothesized that adaptation of heat production in the realimented cow would occur over an extended period, and the length of time would be influenced by the level of feed. our objectives were to quantify the changes in heat production of cows after feed restriction and to quantify the effect of level of realimentation on the dynamics of heat production in lightweight cows. forty 4-yr-old nonpregnant, nonlacting cows (4-breed composite: 1/4 hereford, 1/4 angus, 1/4 red poll, and 1/4 pinzgauer ... | 2006 | 16699100 |
| effect of processing flax in beef feedlot diets on performance, carcass characteristics, and trained sensory panel ratings. | to assess the effects of flax addition and flax processing on feedlot performance and carcass characteristics, 128 yearling beef heifers (360 +/- 14 kg of initial bw) were blocked by weight and assigned randomly to feedlot diets that included no flax (control), whole flax (whl), rolled flax (rld; 1,300 microm), or ground flax (grd; 700 microm). heifers were fed a growth diet (31% corn, 30% corn silage, 18% barley malt pellets, 14% alfalfa, 4% linseed meal, and 3% supplement; dm basis) for 56 d, ... | 2006 | 16699112 |
| effects of nitro compounds and feedstuffs on in vitro methane production in chicken cecal contents and rumen fluid. | short-chain volatile fatty acids (vfa) and methane are the products from a wide variety of microorganisms living in the gastrointestinal tract. the objective of this study was to examine effects of feedstuff and select nitro compounds on vfa and methane production during in vitro incubation of laying hen cecal contents and rumen fluid from cattle and sheep. in the first experiment, one of the three nitro compound was added to incubations containing cecal contents from laying hens supplemented wi ... | 2006 | 16701620 |
| intake and performance of lactating cows grazing diverse forage mixtures. | twenty multiparous holstein cows in midlactation grazed pastures of 4 forage mixtures in a 12-wk study repeated during 2 grazing seasons to determine if forage mixture complexity affected intake and productivity of lactating dairy cows. the forage mixtures were 1) orchardgrass plus white clover [2 species (sp)]; 2) orchardgrass, white clover, and chicory (3sp); 3) orchardgrass, tall fescue, perennial ryegrass, red clover, birdsfoot trefoil, and chicory (6sp); and 4) 6sp mixture plus white clover ... | 2006 | 16702282 |
| lethal risk to birds from insecticide use in the united states--a spatial and temporal analysis. | we used pesticide use data and previously published models to estimate the lethal risk to birds from insecticides used in u.s. agriculture. data from the u.s. department of agriculture's national agricultural statistical service (nass, washington, d.c.) were used to assess how the lethal risk to birds has changed over the period 1991 to 2003 and to compare risk among crop types according to the most recently available surveys. because the nass data coverage is incomplete, both with respect to cr ... | 2006 | 16704051 |
| effects of nutritional environment and ram effect on breeding season in range sheep. | effects of season, nutritional environment, and presence of rams on incidence and rate of ovulation in fine-wool sheep in southern new mexico were investigated over 14 months (february 1983-march 1984). number of corpora lutea (cl) were observed each month by laparoscopy in random samples from six ewes in each subgroup. seasonality of ovulation in fine-wool sheep managed on range was much more marked than in animals managed on alfalfa hay in drylot. incidence of ovulation approached zero in rang ... | 1986 | 16726123 |
| cbra is a stationary-phase regulator of cell surface physiology and legume symbiosis in sinorhizobium meliloti. | sinorhizobium meliloti produces an exopolysaccharide called succinoglycan that plays a critical role in promoting symbiosis with its host legume, alfalfa (medicago sativa). we performed a transposon mutagenesis and screened for mutants with altered succinoglycan production and a defect in symbiosis. in this way, we identified a putative two-component histidine kinase associated with a pas sensory domain, now designated cbra (calcofluor-bright regulator a). the cbra::tn5 mutation causes overprodu ... | 2006 | 16740957 |
| postprandial changes in plasma concentrations of growth hormone and ghrelin around weaning in the goat. | we measured and compared plasma levels of gh and ghrelin in response to feeding in 4-week-old (milk replacer-fed) and 13-week-old (alfalfa hay cube-fed) goats, in order to elucidate whether or not the postprandial regulation of these hormone levels changes around weaning. furthermore, we examined the effects of suckling from the dam or intravenous glucose administration on both hormone and insulin levels in kids. in 4-week-old goats, feeding of a milk replacer diet significantly increased plasma ... | 2006 | 16750532 |
| [modeling of lactic acid fermentation of leguminous plant juices]. | lactic acid fermentation of leguminous plant juices was modeled to provide a comparative efficiency assessment of the previously selected strains of lactic acid bacteria as potential components of starter cultures. juices of the legumes fodder galega, red clover, and alfalfa were subjected to lactic acid fermentation in 27 variants of experiment. local strains (lactobacillus sp. rs 2, lactobacillus sp. rs 3, and lactobacillus sp. rs 4) and the collection strain lactobacillus plantarum bs 933 app ... | 2006 | 16761580 |
| resource availability and quality influence patterns of diet mixing by sheep. | in grazing systems, forage availability is a function of herbivore density, which can influence an animal's ability to be selective. in turn, the influence of food availability on selectivity has the potential to influence plant biodiversity. we hypothesized that the ability of herbivores to mix toxin-containing foods in their diets is a function of the availability of nontoxic foods and the nutritional characteristics of the toxin-containing foods. we evaluated this hypothesis in two trials sim ... | 2006 | 16770717 |
| effect of scraping frequency in a freestall barn on volatile nitrogen loss from dairy manure. | the objective of this investigation was to evaluate the effect of scraping frequency (2x vs. 6x daily) on n volatilization from manure on the floor of a dairy free-stall barn. three trials (crossover design) were conducted in the summers of 2001 and 2002, and in the winter of 2003. nitrogen volatilization was estimated from the change in the n:p ratio in excreta at the time of excretion to the time when manure was scraped from the barn. total n loss was considered a maximum estimate of nh3-n los ... | 2006 | 16772577 |
| effect of selenium supplementation and source on the selenium status of horses. | this study was conducted to determine the effect of se supplementation and source on the se status of horses. eighteen 18-mo-old nonexercised horses were randomly assigned within sex to 1 of 3 treatments: 1) control (ctrl, no supplemental se, 0.15 mg of se/kg of total diet dm); 2) inorganic se (inorg, ctrl + 0.45 mg of se/kg of total diet dm from naseo3); or organic se [org, ctrl + 0.45 mg of se/kg of total diet dm from zinc-l-selenomethionine (availa se, zinpro, corp., eden prairie, mn)]. horse ... | 2006 | 16775058 |
| dissipation of phosalone and diazinon in fresh and dried alfalfa. | the objectives of this study were to determine the persistence of phosalone (s-6-chloro-2,3-dihydro-2-oxobenzoxazol-3-ylmethyl o, o-diethyl phosphorodithioate) and diazinon (o,o-diethyl o-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate) residues in fresh and baled alfalfa under field conditions. plots of alfalfa were sprayed with each insecticide. fresh alfalfa was sampled up to 20 days after treatment, and dried alfalfa was sampled up to 25 weeks after baling. samples were analyzed for resi ... | 2006 | 16785169 |
| circulating fluidized bed combustion product addition to acid soil: alfalfa (medicago sativa l.) composition and environmental quality. | to reduce s emissions, petroleum coke with a high concentration of s was combusted with limestone in a circulating fluidized bed (cfb) boiler. the combustion process creates a bed product that has potential for agricultural uses. this cfb product is often alkaline and enriched in s and other essential plant nutrients, but also contains high concentrations of ni and v. agricultural land application of cfb product is encouraged, but little information is available related to plant responses and en ... | 2006 | 16787025 |
| fixj: a major regulator of the oxygen limitation response and late symbiotic functions of sinorhizobium meliloti. | sinorhizobium meliloti exists either in a free-living state in the soil or in symbiosis within legume nodules, where the bacteria differentiate into nitrogen-fixing bacteroids. expression of genes involved in nitrogen fixation and associated respiration is governed by two intermediate regulators, nifa and fixk, respectively, which are controlled by a two-component regulatory system fixlj in response to low-oxygen conditions. in order to identify the fixlj regulon, gene expression profiles were d ... | 2006 | 16788198 |
| genetic analysis of a baculovirus, autographa californica nuclear polyhedrosis virus i. isolation of temperature-sensitive mutants and assortment into complementation groups. | temperature-sensitive (ts) mutants were isolated from the baculovirus autographa californica (alfalfa looper) mnpv, grown in spodoptera frugiperda (fall armyworm) cells in the presence of n-methyl-n'-nitro-n-nitrosoguanidine. of 567 plaque isolates screened, 27 were temperature sensitive (ts), representing a mutation frequency of 4.8%. ten ts mutants were studied in detail: six failed to yield nonoccluded virus at 33 degrees c (nov mutants), whereas the other four produced nonoccluded virus but ... | 1979 | 16789180 |
| orientation of the genome of autographa californica nuclear polyhedrosis virus: a proposal. | the nuclear polyhedrosis virus of the alfalfa looper autographa californica contains a double-stranded, circular dna genome. fourteen scientists agreed to accept an orientation of this circular genome with respect to a physical map of the restriction endonuclease cleavage sites. | 1982 | 16789218 |
| vsp accumulation and cold-inducible gene expression during autumn hardening and overwintering of alfalfa. | this study describes the time-course of the accumulation of total soluble proteins (tsps) and vegetative storage proteins (vsps) and of the transcripts of cold-inducible (ci) and vsp-encoding genes in taproots of two alfalfa cultivars (ac caribou and europe) during their acclimation to natural autumn hardening and overwintering conditions in eastern canada. the impact of a defoliation in september on these winter hardening-related changes was also assessed. both concentrations and pools of vsps ... | 2006 | 16798845 |
| expression of active hbmp2 in transgenic tobacco plants. | bone morphogenetic protein 2 (bmp2) is important for bone tissue repair. the goal of this research is to construct a high level human bmp2 (hbmp2) expression system using transgenic tobacco plants as a bioreactor. cauliflower mosaic virus (camv) 35s promoter, alfalfa mosaic virus (amv) enhancer, tobacco mosaic virus (tmv) enhancer, matrix attachment regions (mars) sequence, and "kozak" sequence were used to construct recombinant expression vectors and the high-expression vectors were screened ou ... | 2006 | 16819603 |
| diversity of a stable enrichment culture which is useful for silage inoculant and its succession in alfalfa silage. | alfalfa is a kind of forage that is difficult to ensile for good quality. therefore, inoculants are always used to enhance the preservation of alfalfa silage. through continuous restricted subcultivation, a lactic acid bacteria community (al2) was selected from well-fermented alfalfa silage, which sharply decreased the ph level and produced a large amount of lactic acid. the adding of al2 to alfalfa at ensiling resulted in a more rapid drop in ph and higher levels of lactic acid, and it also red ... | 2006 | 16819954 |
| effect of various combinations of alfalfa and standard layer diet on susceptibility of laying hens to salmonella enteritidis during forced molt. | feed deprivation is commonly used by the poultry industry to induce molting and stimulate multiple egg-laying cycles. however, feed deprivation has been observed experimentally to increase susceptibility of poultry to salmonella infections. previous studies indicated that alfalfa was efficacious in reducing salmonella; the present investigation was designed to evaluate the efficacy of combined alfalfa and layer diets on salmonella colonization. leghorn hens over 50 wk of age were divided into 12 ... | 2006 | 16830850 |
| the ntrpr operon of sinorhizobium meliloti is organized and functions as a toxin-antitoxin module. | the chromosomal ntrpr operon of sinorhizobium meliloti encodes a protein pair that forms a toxin-antitoxin (ta) module, the first characterized functional ta system in rhizobiaceae. similarly to other bacterial ta systems, the toxin gene ntrr is preceded by and partially overlaps with the antitoxin gene ntrp. based on protein homologies, the ntrpr operon belongs to the vapbc family of ta systems. the operon is negatively autoregulated by the ntrpntrr complex. promoter binding by ntrp is weak; st ... | 2006 | 16838793 |
| evaluation of dried and wet distillers grains included at two concentrations in the diets of lactating dairy cows. | the purpose of this study was to determine the lactation performance of dairy cows fed dried or wet distillers grains (dg) with solubles (ddgs or wdgs) at 2 dietary concentrations. a trial using 15 cows was designed as a replicated 5 x 5 latin square with periods of 4 wk each and data collected during wk 3 and 4 of each period. diets, on a dry matter basis, were: control, 10% ddgs, 20% ddgs, 10% wdgs, and 20% wdgs. all diets contained 25% corn silage, 25% alfalfa hay, and 50% of the respective c ... | 2006 | 16840630 |
| effects of concentrated separator by-product (desugared molasses) on intake, site of digestion, microbial efficiency, and nitrogen balance in ruminants fed forage-based diets. | in exp. 1, 4 ruminally and duodenally cannulated beef steers (444.0 +/- 9.8 kg) were used in a 4 x 4 latin square with a 2 x 2 factorial treatment arrangement to evaluate the effects of forage type (alfalfa or corn stover) and concentrated separator byproduct (csb) supplementation (0 or 10% of dietary dm) on intake, site of digestion, and microbial efficiency. in exp. 2, 5 wethers (44 +/- 1.5 kg) were used in a 5 x 5 latin square to evaluate the effects of csb on intake, digestion, and n balance ... | 2006 | 16864885 |
| inactivation of escherichia coli 0157:h7 and salmonella on mung beans, alfalfa, and other seed types destined for sprout production by using an oxychloro-based sanitizer. | the efficacy of a stabilized oxychloro-based food grade sanitizer to decontaminate seeds destined for sprout production has been evaluated. by using mung bean seeds as a model system, it was demonstrated that the sanitizer could be used to inactivate a five-strain cocktail of escherichia coli o157:h7 or salmonella introduced onto beans at 10(3) to 10(4) cfu/g. salmonella was more tolerant to stabilized oxychloro than was e. coli o157:h7, with sanitizer levels of >150 and >50 ppm, respectively, b ... | 2006 | 16865888 |
| arabidopsis thaliana is an asymptomatic host of alfalfa mosaic virus. | the susceptibility of arabidopsis thaliana ecotypes to infection by alfalfa mosaic virus (amv) was evaluated. thirty-nine ecotypes supported both local and systemic infection, 26 ecotypes supported only local infection, and three ecotypes could not be infected. no obvious symptoms characteristic of virus infection developed on the susceptible ecotypes under standard conditions of culture. parameters of amv infection were characterized in ecotype col-0, which supported systemic infection and accu ... | 2006 | 16875753 |
| role of non-protein amino acid l-canavanine in autoimmunity. | association of sle and alfalfa was first reported in a volunteer who developed lupus-like autoimmunity while ingesting alfalfa seed for a hypercholesterolemia study. this was corroborated with studies in monkeys fed with alfalfa sprout that developed sle. re-challenge with l-canavanine relapsed the disease. arginine homologue l-canavanine, present in alfalfa, was suspected as a cause. l-canavanine can be charged by arginyl trna synthetase to replace l-arginine during protein synthesis. aberrant ... | 2006 | 16890899 |
| autofluorescence detection of arbuscular mycorrhizal fungal structures in palm roots: an underestimated experimental method. | the aim of this study was to reassess the use of autofluorescence for evaluating am colonization in mycorrhizal roots in the light of criticisms of this method that affirmed that only metabolically inactive arbuscules autofluoresce. it was also investigated whether other mycorrhizal structures, such as hyphae, vesicles and spores, could be detected by autofluorescence, and whether the autofluorescence pattern of am fungal structures could be exploited methodologically, for example, in the detect ... | 2006 | 16893637 |
| ergosterol treatment leads to the expression of a specific set of defence-related genes in tobacco. | ergosterol is the main sterol of most fungi. production of reactive oxygen species after the treatment of tobacco and tomato cells by nano-molar concentrations of ergosterol was previously observed as well as the activation of some stress activated mitogen-activated protein kinases on alfalfa cells. in this paper, the expression of some defence-related genes after the ergosterol treatment of tobacco nicotiana tabacum plants is reported. the gene expression of pathogenesis related proteins of fam ... | 2006 | 16900324 |
| overexpression of bets, a sinorhizobium meliloti high-affinity betaine transporter, in bacteroids from medicago sativa nodules sustains nitrogen fixation during early salt stress adaptation. | sinorhizobium meliloti possesses several betaine transporters to cope with salt stress, and bets represents a crucial high-affinity glycine and proline betaine uptake system involved in the rapid acquisition of betaines by cells subjected to osmotic upshock. using a transcriptional lacz (beta-galactosidase) fusion, we showed that bets is expressed during the establishment of the symbiosis and in mature nitrogen-fixing nodules. however, neither nod nor fix phenotypes were impaired in a bets mutan ... | 2006 | 16903355 |
| isolation of a novel nodulin: a molecular marker of osmotic stress in glycine max/bradyrhizobium japonicum nodule. | symbiotic n(2) fixation of legume crops is highly sensitive to drought, which results in a dramatic drop of n accumulation and yield. the symbiosis between soybean (glycine max) and bradyrhizobium japonicum, because of its extreme sensitivity to drought, was chosen as a model to analyse the response to drought stress at a molecular level. the mrna differential display technique was performed to isolate cdna markers differentially expressed in well-watered [100% of n(2) fixation capacity (nfc)] a ... | 2006 | 16913873 |
| long-term field release of bioluminescent sinorhizobium meliloti strains to assess the influence of a reca mutation on the strains' survival. | a field release experiment was carried out to study the fate of the isogenic, firefly luciferase (luc) gene-tagged sinorhizobium meliloti strains l1 (reca-) and l33 (reca+) in the environment. both strains were released at concentrations of approximately 10(6) cfu g(-1) soil in replicate and randomized field plots, which had been sown with alfalfa (medicago sativa). the survival of both strains during the following 7 years could be subdivided into three phases: a sharp decline for more than two ... | 2006 | 16924432 |
| detection of escherichia coli in packaged alfalfa sprouts with an electronic nose and an artificial neural network. | a rapid method for the detection of escherichia coli (atcc 25922) in packaged alfalfa sprouts was developed. volatile compounds from the headspace of packaged alfalfa sprouts, inoculated with e. coli and incubated at 10 degrees c for 1, 2, and 3 days, were collected and analyzed. uninoculated sprouts were used as control samples. an electronic nose with 12 metal oxide electronic sensors was used to monitor changes in the composition of the gas phase of the package headspace with respect to volat ... | 2006 | 16924908 |
| [a luxr family regulator, expr regulates the expression of motc operon from sinorhizobium meliloti]. | in sinorhizobium meliloti strain rm1021, expr+ mutation results in the overproduction of eps ii, which is required for efficient invasion of root nodules on the host plant alfalfa. when rhizobia were grown in lb/mc medium for 36-hour then placed at room temperature, most of expr+ mutant (rm8530) cells aggregated at the bottom of the tubes, but expr+ sinr double mutant rm11528 and wild type rm1021 did not. the expr+ mutant was also found to swim slower than rm1021 on swarming plates, but the expr ... | 2006 | 16933625 |
| detection and differentiation of xylella fastidiosa strains acquired and retained by glassy-winged sharpshooters (hemiptera: cicadellidae) using a mixture of strain-specific primer sets. | xylella fastidiosa wells is a bacterial pathogen that causes a variety of plant diseases, including pierce's disease (pd) of grapevine, almond leaf scorch, alfalfa dwarf, citrus variegated chlorosis, and oleander leaf scorch (ols). numerous strains of this pathogen have been genetically characterized, and several different strains occur in the united states. the dominant vector in southern california is the glassy-winged sharpshooter, homalodisca coagulata (say) (hemiptera: cicadellidae). the hi ... | 2006 | 16937656 |
| yield and forage quality of glandular-haired alfalfa under alfalfa weevil (coleoptera: curculionidae) and potato leafhopper (hemiptera: cicadellidae) pest pressure in virginia. | cultivars of glandular-haired alfalfa, medicago sativa l., such as '54h69', are currently available and marketed as being resistant to potato leafhopper, empoasca fabae (harris) (hemiptera: cicadellidae). 54h69 and a standard, nonglandular-haired alfalfa 'choice' were evaluated at two locations in virginia over a 3-yr period. dry matter yields and concentrations of crude protein and acid detergent fiber were compared at the first, second, and third harvests. overall, the two cultivars produced s ... | 2006 | 16937677 |
| cloning, expression, and mapping of gdp-d-mannose pyrophosphorylase cdna from tomato (lycopersicon esculentum). | gdp-d-mannose pyrophosphorylase (gmp, ec 2.7.7.22) catalyzes the synthesis of gdp-d-mannose and represents the first committed step in plant ascorbic acid biosynthesis. using potato gmp cdna sequence as a querying probe, 65 highly homologous tomato ests were obtained from dbest of genbank and the putative cdna sequence of tomato gmp was assembled. the full-length gmp cdna of tomato was cloned by race-pcr with primers designed according to the assembled cdna sequence. the full-length cdna sequenc ... | 2006 | 16939010 |
| effect of thyme essential oils (thymus hyemalis and thymus zygis) and monensin on in vitro ruminal degradation and volatile fatty acid production. | the effect of the essential oils of thyme on the in vitro ruminal degradability of a barley seed/alfalfa hay substrate was studied. two essential oils were used, one from thymus hyemalis (th), rich in carvacrol, and the other from thymus zygis (tz), rich in thymol. four experimental treatments of in vitro degradability, using the daisy ii(200/220) incubator, were conducted including a negative control (co), a positive control at 7.5 microg/ml of monensin (mo), and two treatments with essential o ... | 2006 | 16939315 |
| metabolite profiles of nodulated alfalfa plants indicate that distinct stages of nodule organogenesis are accompanied by global physiological adaptations. | an effective symbiosis between sinorhizobium meliloti and its host plant medicago sativa is dependent on a balanced physiological interaction enabling the microsymbiont to fix atmospheric nitrogen. maintenance of the symbiotic interaction is regulated by still poorly understood control mechanisms. a first step toward a better understanding of nodule metabolism was the determination of characteristic metabolites for alfalfa root nodules. furthermore, nodules arrested at different developmental st ... | 2006 | 16941904 |
| effect of varying dietary ratios of alfalfa silage to corn silage on production and nitrogen utilization in lactating dairy cows. | twenty-eight (8 ruminally cannulated) lactating, multiparous holstein cows were blocked by dim and randomly assigned to 7 replicated 4 x 4 latin squares (28-d periods) to investigate the effects of different dietary ratios of alfalfa silage (as) to corn silage (cs) on production, n utilization, apparent digestibility, and ruminal metabolism. the 4 diets contained (dry matter basis): a) 51% as, 43% rolled high-moisture shelled corn (hmsc), and 3% solvent soybean meal (ssbm); b) 37% as, 13% cs, 39 ... | 2006 | 16960068 |
| effect of varying dietary ratios of alfalfa silage to corn silage on omasal flow and microbial protein synthesis in dairy cows. | eight ruminally cannulated multiparous holstein cows that were part of a larger production trial were used to study the effects of varying dietary ratios of alfalfa silage (as) to corn silage (cs) on omasal flow of nutrients and microbial protein. cows were blocked by dim and randomly assigned to 2 replicated 4 x 4 latin squares (28-d periods). diets fed contained (dry matter basis): a) 51% as, 43% rolled high-moisture shelled corn (hmsc), and 3% solvent soybean meal (ssbm); b) 37% as, 13% cs, 3 ... | 2006 | 16960069 |
| effects of alfalfa extract, anise, capsicum, and a mixture of cinnamaldehyde and eugenol on ruminal fermentation and protein degradation in beef heifers fed a high-concentrate diet. | four holstein heifers (360 +/- 22 and 450 +/- 28 kg of bw in exp. 1 and 2, respectively) fitted with ruminal trocars were used in 4 x 4 latin square designs to evaluate the effects on ruminal microbial fermentation of the following: exp. 1, no additive, alfalfa extract (30 g/d, aex), a mixture of cinnamaldehyde (0.18 g/d) and eugenol (0.09 g/d; cie1), and aex and cie1 in combination; and exp. 2, no additive, anise oil (2 g/d), capsicum oil (1 g/d), and a mixture of cinnamaldehyde (0.6 g/d) and e ... | 2006 | 16971582 |
| effects of cyanobacterial toxins and cyanobacterial cell-free crude extract on germination of alfalfa (medicago sativa) and induction of oxidative stress. | cyanobacterial toxins have adverse effects on both terrestrial and aquatic plants. microcystins are cyclic heptapeptides and an important group of cyanotoxins. when lake water contaminated with cyanobacterial blooms is used for spray irrigation, these toxins can come in contact with agricultural plants. during the exposure to these toxins, reactive oxygen species can form. these reactive oxygen species have a strong reactivity and are able to interact with other cellular compounds (lipids, prote ... | 2006 | 16986793 |
| alfalfa (medicago sativa l.). | a protocol for rapid, highly efficient transformation of alfalfa is described. leaf explants from growth chamber-grown plants of a highly regenerable genotype are surface-sterilized, the margins are removed, and explants are inoculated with agrobacterium tumefaciens strain lba4404 carrying the t-dna vector of interest. the explants and bacteria are cocultured for 7 to 8 d. bacteria are removed by rinsing explants in sterile distilled water and by culture on regeneration medium containing the ant ... | 2006 | 16988354 |
| rhizosphere microbial activity during phytoremediation of diesel-contaminated soil. | to know microbial activity and diesel-removal efficiency influencing through plant roots, we examined the effect of the rhizosphere on phytoremediation of diesel-contaminated soils by alfalfa (medicago sativa l.). pots were treated with and without diesel and allowed to stabilize for 7 weeks, at which time four experimental/control groups were prepared: (1) planted diesel-contaminated soil, (2) unplanted diesel-contaminated soil, (3) planted uncontaminated soil, and (4) unplanted uncontaminated ... | 2006 | 17000542 |
| sinorhizobium meliloti nifa mutant induces different gene expression profile from wild type in alfalfa nodules. | several studies have demonstrated that the rhizobium nifa gene is an activator of nitrogen fixation acting in nodule bacteria. to understand the effects of the sinorhizobium meliloti nifa gene on alfalfa, the cdna-aflp technique was employed to study the changes in gene expression in nifa mutant nodules. among the approximately 3,000 transcript-derived fragments, 37 had differential expression levels. these expression levels were subsequently confirmed by reverse northern blot and rt-polymerase ... | 2006 | 17001343 |
| antidermatophyte activity of medicago extracts and contained saponins and their structure-activity relationships. | saponin-rich extracts of medicago sativa l. have been shown to display antifungal activity against a range of common fungibut only a few individual saponins have been tested against dermatophytes. total saponins were separately obtained from roots and aerial parts of medicago sativa, m. murex, m. arabica and m. hybrida. nineteen saponins and three parent triterpenoids, were tested against three dermatophytic fungi microsporum gypseum, trichophyton interdigitale and t. tonsurans using mircowell p ... | 2006 | 17006971 |
| salt-tolerant rhizobia isolated from a tunisian oasis that are highly effective for symbiotic n2-fixation with phaseolus vulgaris constitute a novel biovar (bv. mediterranense) of sinorhizobium meliloti. | nodulation of common bean was explored in six oases in the south of tunisia. nineteen isolates were characterized by pcr-rflp of 16s rdna. three species of rhizobia were identified, rhizobium etli, rhizobium gallicum and sinorhizobium meliloti. the diversity of the symbiotic genes was then assessed by pcr-rflp of nodc and nifh genes. the majority of the symbiotic genotypes were conserved between oases and other soils of the north of the country. sinorhizobia isolated from bean were then compared ... | 2007 | 17019605 |
| mesorhizobium loti produces nodpq-dependent sulfated cell surface polysaccharides. | leguminous plants and bacteria from the family rhizobiaceae form a symbiotic relationship, which culminates in novel plant structures called root nodules. the indeterminate symbiosis that forms between sinorhizobium meliloti and alfalfa requires biosynthesis of nod factor, a beta-1,4-linked lipochitooligosaccharide that contains an essential 6-o-sulfate modification. s. meliloti also produces sulfated cell surface polysaccharides, such as lipopolysaccharide (lps). the physiological function of s ... | 2006 | 17028279 |
| slow-release urea and highly fermentable sugars in diets fed to lactating dairy cows. | this experiment was designed to test the inclusion of highly fermentable sugars (fs) in dairy rations and their interactions with a slow-release urea (su) product. the fs are a blend of liquid coproducts from the corn milling and cheese industries, and the su is calcium chloride urea. eight multiparous and 4 primiparous brown swiss cows (117 +/- 46 d in milk) were blocked by parity and utilized in a multiple latin square design. basal diets were formulated for 16.6% crude protein and 1.55 mcal/k ... | 2006 | 17033027 |
| hydroperoxide lyases (cyp74c and cyp74b) catalyze the homolytic isomerization of fatty acid hydroperoxides into hemiacetals. | the conversion of linoleic acid 9-hydroperoxide (9-hpod) by recombinant melon (cucumis melo l.) hydroperoxide lyase (hpl, cyp74c subfamily) was studied. short (5 s-1 min) incubations at 0 degrees c followed by rapid extraction and trimethylsilylation made it possible to trap a new unstable (t(1/2) <30 s) product, i.e. the hemiacetal (1'e,3'z)-9-hydroxy-9-(1',3'-nonadienyloxy)-nonanoic acid. identification was performed by gc-ms analysis and substantiated by the formation of trimethylsilyl 9-trim ... | 2006 | 17049304 |
| sinorhizobium meliloti genes involved in tolerance to the antimicrobial peptide protamine. | the innate resistance of plants and animals to microbial infection is mediated in part by small cationic peptides with antimicrobial activity. we assessed the susceptibility of the alfalfa symbiont sinorhizobium meliloti to the model antimicrobial peptide protamine. twenty-one tn5-induced mutants showing increased sensitivity to protamine were isolated, and nine were further characterized in detail. these nine mutants carried distinct transposon insertions that affected a total of seven differen ... | 2006 | 17064369 |
| malic enzyme cofactor and domain requirements for symbiotic n2 fixation by sinorhizobium meliloti. | the nad(+)-dependent malic enzyme (dme) and the nadp(+)-dependent malic enzyme (tme) of sinorhizobium meliloti are representatives of a distinct class of malic enzymes that contain a 440-amino-acid n-terminal region homologous to other malic enzymes and a 330-amino-acid c-terminal region with similarity to phosphotransacetylase enzymes (pta). we have shown previously that dme mutants of s. meliloti fail to fix n(2) (fix(-)) in alfalfa root nodules, whereas tme mutants are unimpaired in their n(2 ... | 2007 | 17071765 |
| multiple gene genealogical analyses reveal both common and distinct population genetic patterns among replicons in the nitrogen-fixing bacterium sinorhizobium meliloti. | sinorhizobium meliloti is a gram-negative alpha-proteobacterium that can form symbiotic relationships with alfalfa and fix atmospheric nitrogen. the complete genome of a laboratory strain, rm1021, was published in 2001, and the genome of this strain is arranged in three replicons: a chromosome of 3.65 million base pairs (mb), and two megaplasmids, psyma (1.35 mb) and psymb (1.68 mb). however, the potential difference in genetic variation among the three replicons in natural strains remains poorl ... | 2006 | 17074896 |
| rhizobium lusitanum sp. nov. a bacterium that nodulates phaseolus vulgaris. | the species phaseolus vulgaris is a promiscuous legume nodulated by several species of the family rhizobiaceae. during a study of rhizobia nodulating this legume in portugal, we isolated several strains that nodulate p. vulgaris effectively and also macroptilium atropurpureum and leucaena leucocephala, but they form ineffective nodules in medicago sativa. according to phylogenetic analysis of the 16s rrna gene sequence, the strains from this study belong to the genus rhizobium, with rhizobium rh ... | 2006 | 17082403 |
| tissue distribution, elimination, and metabolism of sodium [36cl]perchlorate in lactating goats. | perchlorate has contaminated water sources throughout the united states but particularly in the arid southwest, an area containing large numbers of people and few water sources. recent studies have demonstrated that perchlorate is present in alfalfa and that perchlorate is secreted into the milk of cows. studies in lactating cows have indicated that only a small portion of a perchlorate dose could be accounted for by elimination in milk, feces, or urine. it was hypothesized that the remainder of ... | 2006 | 17090130 |
| effect of chestnut tannin on fermentation quality, proteolysis, and protein rumen degradability of alfalfa silage. | two experiments were conducted on alfalfa to investigate the effects of the addition of commercial chestnut hydrolyzable tannin at ensiling on 1) silage fermentation quality in lab-scale silos and protein degradation in the rumen, and 2) silage fermentation quality and proteolysis in bale silages. wilted alfalfa was prepared with 4 tannin levels (0, 2, 4, and 6% on a dry matter (dm) basis; t0, t1, t2, t3, respectively) and ensiled in lab-scale silos. silages (33% dm) were analyzed for fermentati ... | 2006 | 17106105 |
| effects of rumen acid load from feed and forage particle size on ruminal ph and dry matter intake in the lactating dairy cow. | the objective of this study was to evaluate the effects of level of concentrate acidogenic value (av) and forage particle size on ruminal ph and feed intake in lactating dairy cows. two isoenergetic (net energy for lactation = 1.5 +/- 0.01 mcal/kg) and isonitrogenous (crude protein = 17.4 +/- 0.1% dry matter) concentrates with either a low av or high av were formulated and fed in a total mixed ration with either coarsely or finely chopped corn silage and alfalfa haylage ad libitum. four rumen-fi ... | 2006 | 17106107 |
| batch fermentations on synthetic mixed sugar and starch medium with amylolytic lactic acid bacteria. | the green crop drying industry in denmark uses italian rye grass, clover, and alfalfa as raw materials for the production of green pellets. the green crop drying industry solves its energy economical problems by heating and pressing of the green crop before drying. the produced sidestream is called brown juice. brown juice was shown to be an excellent medium for lactic acid fermentation. the aim of this study was to investigate the utilisation of brown juice in the production of polylactic acid, ... | 2007 | 17109171 |
| burden and causes of foodborne disease in australia: annual report of the ozfoodnet network, 2005. | in 2005, ozfoodnet sites recorded 25,779 notifications of seven potentially foodborne diseases, which was 12.5 per cent higher than the mean for the previous five years. diseases with significant increases in 2005, when compared to historical reports include: shiga toxin-producing escherichia coli, shigellosis, haemolytic uraemic syndrome, salmonellosis and campylobacteriosis. the most significant increases were those due to salmonella (13.1%) and campylobacter (5.1%) because of the frequency of ... | 2006 | 17120483 |
| potential for phytoremediation of polychlorinated biphenyl-(pcb-)contaminated soil. | weathered soils contaminated with commercial-grade aroclor 1260 from three sites in canada were used to investigate the polychlorinated biphenyl (pcb) phytoextraction potential of nine plant species (festuca arundinacea, glycine max, medicago sativa, phalaris arundinacea, lolium multiflorum, carex normalis, and three varieties of cucurbita pepo ssp. pepo) under controlled greenhouse conditions. the soils used varied in pcb concentration (90-4200 microg/g) and total organic content (0.06-2.02%). ... | 2006 | 17120525 |
| effects of a dietary aspergillus oryzae extract containing alpha-amylase activity on performance and carcass characteristics of finishing beef cattle. | three experiments were conducted to examine the effects of an aspergillus oryzae extract containing alpha-amylase activity on performance and carcass characteristics of finishing beef cattle. in exp. 1, 120 crossbred steers were used in a randomized complete block design to evaluate the effects of roughage source (alfalfa hay vs. cottonseed hulls) and supplemental alpha-amylase at 950 dextrinizing units (du)/kg of dm. significant roughage source x alpha-amylase interactions (p < 0.05) were obser ... | 2007 | 17121970 |
| immunological evaluation of sw-hsa conjugate on goats. | locoweeds cause significant livestock poisoning and economic loss all over the world. the purpose of this study was to investigate the immune effects of locoweed toxin, swainsonine (sw) and human serum albumin (hsa) conjugate (sw-hsa), on goats. twenty-four sannon goats were randomly separated into immune control group (eight goats), immune poisoning group i (six goats), immune poisoning group ii (six goats) and poisoning control group (four goats). immune control group, immune poisoning groups ... | 2007 | 17126535 |
| monoclonal c5-1 antibody produced in transgenic alfalfa plants exhibits a n-glycosylation that is homogenous and suitable for glyco-engineering into human-compatible structures. | structural analysis of the n-glycosylation of alfalfa proteins was investigated in order to evaluate the capacity of this plant to perform this biologically important post-translational modification. we show that, in alfalfa, n-linked glycans are processed into a large variety of mature oligosaccharides having core-xylose and core alpha(1,3)-fucose, as well as terminal lewis(a) epitopes. in contrast, expression of the c5-1 monoclonal antibody in alfalfa plants results in the production of plant- ... | 2003 | 17134403 |
| fermentation quality and nutritive value of a total mixed ration silage containing coffee grounds at ten or twenty percent of dry matter. | six wethers were used in a replicated 3 x 3 latin square to study the fermentation quality and nutritive value of total mixed ration (tmr) silages that included wet coffee grounds (wcg). the tmr were prepared using a commercial compound feed, timothy hay, alfalfa hay, dried beet pulp, and a vitamin-mineral supplement in a ratio of 36.5:30:20:12:1.5, respectively, on a dm basis, with timothy hay and alfalfa hay being replaced by wcg at 0, 10, or 20%. all tmr silages, irrespective of wcg addition, ... | 2007 | 17145973 |
| optimized expression vector for ion channel studies in xenopus oocytes and mammalian cells using alfalfa mosaic virus. | plasmid vectors used for mammalian expression or for in vitro crna translation can differ substantially and are rarely cross-compatible. to make comparisons between mammalian and xenopus oocyte expression systems, it would be advantageous to use a single vector without the need for shuttle vectors or subcloning. we have designed such a vector, designated puniv for universal, with elements that will allow for in vitro or ex vivo expression in multiple cell types. we tested the expression of puniv ... | 2007 | 17146677 |
| spider dragline silk proteins in transgenic tobacco leaves: accumulation and field production. | spider dragline silk is a unique biomaterial and represents nature's strongest known fibre. as it is almost as strong as many commercial synthetic fibres, it is suitable for use in many industrial and medical applications. the prerequisite for such a widespread use is the cost-effective production in sufficient quantities for commercial fibre manufacturing. agricultural biotechnology and the production of recombinant dragline silk proteins in transgenic plants offer the potential for low-cost, l ... | 2004 | 17168889 |
| [composition diversity of lactic acid bacteria (lab) community al2 used for alfalfa silage]. | alfalfa is the most important forage grass that is difficult to ensile for good quality. using silage inoculants are the important way for preservation of alfalfa silage. through continuous restricted subcultivation, a lactic acid bacteria (lab) community al2 was selected from well-fermented alfalfa silage. plate isolation and denaturing gradient gel electrophoresis (dgge), construction of 16s rdna clone library were used to identify the composition diversity of al2 community, with 7 strains det ... | 2006 | 17172026 |
| identification of novel sinorhizobium meliloti mutants compromised for oxidative stress protection and symbiosis. | employing a novel two-part screen, we identified sinorhizobium meliloti mutants that were both sensitive to hydrogen peroxide and symbiotically defective on the host plant medicago sativa. the mutations affect a wide variety of cellular processes and represent both novel and previously identified genes important in symbiosis. | 2007 | 17172326 |
| disruption of sita compromises sinorhizobium meliloti for manganese uptake required for protection against oxidative stress. | during the initial stages of symbiosis with the host plant medicago sativa, sinorhizobium meliloti must overcome an oxidative burst produced by the plant in order for proper symbiotic development to continue. while identifying mutants defective in symbiosis and oxidative stress defense, we isolated a mutant with a transposon insertion mutation of sita, which encodes the periplasmic binding protein of the putative iron/manganese abc transporter sitabcd. disruption of sita causes elevated sensitiv ... | 2007 | 17172335 |
| biodegradation of atrazine in transgenic plants expressing a modified bacterial atrazine chlorohydrolase (atza) gene. | atrazine is one of the most widely used herbicides in the usa. atrazine chlorohydrolase (atza), the first enzyme in a six-step pathway leading to the mineralization of atrazine in gram-negative soil bacteria, catalyses the hydrolytic dechlorination and detoxification of atrazine to hydroxyatrazine. in this study, we investigated the potential use of transgenic plants expressing atza to take up, dechlorinate and detoxify atrazine. alfalfa, arabidopsis thaliana and tobacco were transformed with a ... | 2005 | 17173634 |
| a proteasome-regulated glycogen synthase kinase-3 modulates disease response in plants. | glycogen synthase kinase-3 (gsk-3) is a key player in various important signaling pathways in animals. the activity of gsk-3 is known to be modulated by protein phosphorylation and differential complex formation. however, little information is available regarding the function and regulation of plant gsk-3/shaggy-like kinases (gsks). analysis of the in vivo kinase activity of msk1, a gsk from medicago sativa, revealed that msk1 is active in healthy plants and that msk1 activity is down-regulated ... | 2007 | 17179144 |
| effect of substitution of a soybean hull and grape seed meal mixture for traditional fiber sources on digestion and performance of growing rabbits and lactating does. | the aim of this work was to determine what concentration of a mixture of soybean hulls and defatted grape seed meal (shdg) could be included in diets that meet or exceed adl and particle size requirements for rabbits. four isonitrogenous and isofibrous pelleted diets were formulated, with similar adl concentration and particle size (18.3% cp, 42.6% ndf, 7.1% adl, and 34.9% of particles larger than 0.315 mm, on a dm basis). diets contained a constant ratio of soybean hulls:defatted grape seed mea ... | 2007 | 17179554 |
| technical note: a system for continuous recording of ruminal ph in cattle. | continuous recording of ruminal ph in cannulated cattle has been practiced to study rumen metabolism. however, most systems reported did not permit animal mobility during ph recording. therefore, the objective of this study was to develop a continuous rumen ph data acquisition system that permitted animal mobility during data acquisition. a further objective was to compare the ph readings obtained using the continuous recording system to readings obtained at the same time using spot sampling. th ... | 2007 | 17179558 |
| engineering of a sialic acid synthesis pathway in transgenic plants by expression of bacterial neu5ac-synthesizing enzymes. | plants are a low-cost and contamination-free factory for the production of recombinant pharmaceutical proteins. however, plant-made pharmaceuticals differ from their mammalian homologues by the structure of their n-linked glycans. for instance, most mammalian glycoproteins harbour terminal sialic acids that control their half-life in the bloodstream. the absence of the whole sialylation machinery in plants is of major concern as non-sialylated plant-made pharmaceuticals may not perform at their ... | 2007 | 17207253 |
| solid-state cultures of fusarium oxysporum transform aromatic components of olive-mill dry residue and reduce its phytotoxicity. | the present study mainly investigated the ability of solid-state cultures of the non-pathogenic fusarium oxysporum strain bafc 738 to transform aromatic components to reduce the phytotoxicity in olive-mill dry residue (dor), the waste from the two-phase manufacturing process. lignin, hemicellulose, fats and water-soluble extractives contents of dor colonized by the fungus for 20 weeks were reduced by 16%, 25%, 71% and 13%, respectively, while the cellulose content increased by 25%. in addition, ... | 2007 | 17207620 |
| sinorhizobium meliloti syra mediates the transcriptional regulation of genes involved in lipopolysaccharide sulfation and exopolysaccharide biosynthesis. | sinorhizobium meliloti is a gram-negative soil bacterium found either in free-living form or as a nitrogen-fixing endosymbiont of leguminous plants such as medicago sativa (alfalfa). s. meliloti synthesizes an unusual sulfate-modified form of lipopolysaccharide (lps). a recent study reported the identification of a gene, lpss, which encodes an lps sulfotransferase activity in s. meliloti. mutants bearing a disrupted version of lpss exhibit an altered symbiosis, in that they elicit more nodules t ... | 2007 | 17209018 |
| [diurnal dynamics of photosynthetic and transpiration rates of alfalfa under dry farming and their relationships with environmental factors]. | in this paper, the diurnal dynamics of photosynthetic rate (pn) and transpiration rate ( tr) of four years planted alfalfa under dry farming, as well as those of photosynthetic active radiation (par) , co2 concentration in field ( ca ) , relative humidity (rh) and air temperature ( ta) were measured, and the relationships between the diurnal dynamics of pn, tr and climatic factors were analyzed by correlation coefficient, path coefficient, and decision coefficient analyses. the results showed th ... | 2006 | 17209375 |
| elevated atmospheric co2 and strain of rhizobium alter freezing tolerance and cold-induced molecular changes in alfalfa (medicago sativa). | the objective of the study was to assess the impact of elevated co2 in interaction with rhizobial strains on freezing tolerance and cold-induced molecular changes in alfalfa. | 2007 | 17218341 |
| plant-microbe association for rhizoremediation of chloronitroaromatic pollutants with comamonas sp. strain cnb-1. | comamonas sp. strain cnb-1, isolated from activated sludge and having a strong ability to degrade 4-chloronitrobenzene (4cnb), was applied for rhizoremediation of 4cnb-polluted soil through association with alfalfa. confocal laser scanning microscopy revealed that strain cnb-1 successfully colonized alfalfa roots. determination of strain cnb-1 populations by cultivation method and by quantitative competitive pcr technique targeting the chloronitrobenzene nitroreductase gene showed that the popul ... | 2007 | 17222144 |
| the sinorhizobium meliloti exor protein is required for the downregulation of lpss transcription and succinoglycan biosynthesis in response to divalent cations. | the sinorhizobium meliloti lpss gene encodes a sulfotransferase that modifies lipopolysaccharide. mutants lacking lpss display no defect in lipopolysaccharide sulfation when assayed under laboratory conditions, but exhibit an abnormal symbiosis with alfalfa. these results suggest that lpss is transcriptionally repressed under laboratory conditions, but upregulated during symbiosis. here, it is shown that lpss, as well as exo genes required for the biosynthesis of succinoglycan, are transcription ... | 2007 | 17233674 |
| milk from forage as affected by rumen degradable protein and corn grinding when feeding corn- and alfalfa silage-based diets. | to increase the production of milk from forage (mf), a previous experiment with alfalfa silage showed the importance of a complementary combination of concentrates and forages offered. when corn silage is fed with alfalfa, increasing the rumen degradable protein (rdp) content in the diet should allow a better utilization of forage energy. to evaluate this hypothesis, 8 multiparous holstein cows in early lactation were used in a replicated 4 x 4 latin square design with 3-wk periods. diets were f ... | 2007 | 17235159 |
| effects of essential oils on digestion, ruminal fermentation, rumen microbial populations, milk production, and milk composition in dairy cows fed alfalfa silage or corn silage. | four holstein cows fitted with ruminal cannulas were used in a 4 x 4 latin square design (28-d periods) with a 2 x 2 factorial arrangement of treatments to investigate the effects of addition of a specific mixture of essential oil compounds (meo; 0 vs. 750 mg/d) and silage source [alfalfa silage (as) vs. corn silage (cs)] on digestion, ruminal fermentation, rumen microbial populations, milk production, and milk composition. total mixed rations containing either as or cs as the sole forage source ... | 2007 | 17235165 |
| the symbiosis regulator cbra modulates a complex regulatory network affecting the flagellar apparatus and cell envelope proteins. | sinorhizobium meliloti participates in a nitrogen-fixing symbiosis with legume plant host species of the genera medicago, melilotus, and trigonella. we recently identified an s. meliloti two-component sensory histidine kinase, cbra, which is absolutely required to establish a successful symbiosis with medicago sativa (k. e. gibson, g. r. campbell, j. lloret, and g. c. walker, j. bacteriol. 188:4508-4521, 2006). in addition to having a symbiotic defect, the cbra::tn5 mutant also has free-living p ... | 2007 | 17237174 |
| combination of a urease inhibitor and a plant essential oil to control coliform bacteria, odour production and ammonia loss from cattle waste. | to evaluate urea hydrolysis, volatile fatty acid (vfa) production (odour) and coliforms in cattle waste slurries after a urease inhibitor n-(n-butyl) thiophosphoric triamide (nbpt) and a plant oil component (thymol) were added. | 2007 | 17241353 |
| extended region of nodulation genes in rhizobium meliloti 1021. i. phenotypes of tn5 insertion mutants. | rhizobium meliloti nod(-) mutant wl131, a derivative of wild-type strain 102f51, was complemented by a clone bank of wild-type r. meliloti 1021 dna, and clone prmjt5 was recovered. transfer of prmjt5 conferred alfalfa nodulation on other rhizobium species, indicating a role in host range determination for prmjt5. mutagenesis of prmjt5 revealed several segments in which transposon insertion causes delay in nodulation, and/or marked reduction of the number of nodules formed on host alfalfa plants. ... | 1987 | 17246399 |
| resuscitation of viable but not culturable sinorhizobium meliloti 41 prp4-luc: effects of oxygen and host plant. | a plasmid-borne, firefly-derived, luciferase gene (luc) was inserted and stably inherited in sinorhizobium meliloti 41 as a reporter gene. the strain obtained, s. meliloti 41/prp4-luc, and its parental strain served as a model system for viable but not culturable (vbnc) resuscitation experiments in both in vitro and soil samples. incubation under oxygen (02) concentrations varying from 1% to atmospheric levels did not result in resuscitation. a demonstration of recovery was attained through expo ... | 2007 | 17253091 |
| a sinorhizobium meliloti mine mutant has an altered morphology and exhibits defects in legume symbiosis. | sinorhizobium meliloti differentiates from rod-shaped, free-living cells into pleomorphic, non-dividing, n(2)-fixing bacteroids within alfalfa root nodules. here, the role of the mincde genes in bacteroid differentiation and in free-living cell division is examined. disruption of the mine gene resulted in large, swollen and branched free-living cells, and in symbiosis a mine mutation resulted in a defect in nitrogen fixation with activity reduced by approximately 70 % compared to the wild-type. ... | 2007 | 17259609 |
| roles of poly-3-hydroxybutyrate (phb) and glycogen in symbiosis of sinorhizobium meliloti with medicago sp. | poly-3-hydroxybutyrate (phb) and glycogen are major carbon storage compounds in sinorhizobium meliloti. the roles of phb and glycogen in rhizobia-legume symbiosis are not fully understood. glycogen synthase mutations were constructed by in-frame deletion (glga1) or insertion (glga2). these mutations were combined with a phbc mutation to make all combinations of double and triple mutants. phb was not detectable in any of the mutants containing the phbc mutation; glycogen was not detectable in any ... | 2007 | 17259610 |
| [community structure and its dynamics of predatory arthropod in jujube orchards intercropped with different herbage species]. | by using community structural characteristic indices and principal component analysis, this paper studied the community structure and its dynamics of predatory arthropod in the jujube orchards intercropped with astrugalus complanatus, trifolium repen, lotus comiculotus, and medicago sativa. the results showed that in all test jujube orchards, spider and predatory insects were the predominant components of the predatory arthropod community, and their relative abundances were 48.3% - 52.7% and 38. ... | 2006 | 17269332 |
| effects of feeding formate-treated alfalfa silage or red clover silage on the production of lactating dairy cows. | in trial 1, 15 holsteins were fed 3 total mixed rations (tmr) with 33% neutral detergent fiber in 3 x 3 latin squares (28-d periods). two tmr contained (dry matter basis): 40% control alfalfa silage (cas) or 40% ammonium tetraformate-treated alfalfa silage (tas), 20% corn silage (cs), 33% high-moisture shelled corn (hmsc), 6% solvent soybean meal (ssbm), and 18% crude protein (cp); the third tmr contained 54% red clover silage (rcs), 6% dried molasses, 33% hmsc, 6% ssbm, and 16.3% cp. silages di ... | 2007 | 17297112 |
| effects of feeding formate-treated alfalfa silage or red clover silage on omasal nutrient flow and microbial protein synthesis in lactating dairy cows. | eight ruminally cannulated holstein cows that were part of a larger lactation trial were blocked by days in milk and randomly assigned to replicated 4 x 4 latin squares to quantify effects of nonprotein n (npn) content of alfalfa silage (as) and red clover silage (rcs) on omasal nutrient flows. diets, fed as total mixed rations, contained 50% dry matter from control as (cas), ammonium tetraformate-treated as (tas), late maturity rcs (rcs1), or early maturity rcs (rcs2). silages differed in npn a ... | 2007 | 17297113 |
| kinetics of fatty acid biohydrogenation in vitro. | biohydrogenation (bh) of fatty acids (fa) from fresh alfalfa and alfalfa hay with varying levels of supplemental sucrose and media ph was evaluated in vitro. a multicompartmental model was then developed to estimate pool size and flux of vaccenic acid (va) during bh of fa in fresh alfalfa. to vary incubation ph, alfalfa samples were inoculated with rumen fluid in 2 media differing in molarity of the bicarbonate buffer. samples were incubated for 0, 1, 2, 3, 4, 6, 9, and 12 h; ph was measured and ... | 2007 | 17297114 |
| use of exogenous fibrolytic enzymes to enhance in vitro fermentation of alfalfa hay and corn silage. | two in vitro experiments were performed to identify promising exogenous fibrolytic enzyme products (efe) and optimum dose rates (dr) for improving the degradation of alfalfa hay and corn silage. the relationship between enzymatic activity and fermentation responses was examined to identify optimum formulations. in experiment 1, 5 efe containing mainly endoglucanase and xylanase activities, with different ratios between the 2 activities, were assessed at a dr of 0.7, 1.4, and 2.1 mg/g of dm forag ... | 2007 | 17297117 |
| identification and characterization of a nodh ortholog from the alfalfa-nodulating or191-like rhizobia. | nodulation of medicago sativa (alfalfa) is known to be restricted to sinorhizobium meliloti and a few other rhizobia that include the poorly characterized isolates related to rhizobium sp. strain or191. distinctive features of the symbiosis between alfalfa and s. meliloti are the marked specificity from the plant to the bacteria and the strict requirement for the presence of sulfated lipochitooligosaccharides (nod factors [nfs]) at its reducing end. here, we present evidence of the presence of a ... | 2007 | 17313165 |
| dissipation of 2,4-d in soils of the humid pampa region, argentina: a microcosm study. | phenoxy herbicides like 2,4-dichlorophenoxyacetic acid (2,4-d) are widely used in agricultural practices. although its half life in soil is 7-14d, the herbicide itself and its first metabolite 2,4-dichlorophenol (2,4-dcp) could remain in the soil for longer periods, as a consequence of its intensive use. microcosms assays were conducted to study the influence of indigenous microflora and plants (alfalfa) on the dissipation of 2,4-d from soils of the humid pampa region, argentina, with previous h ... | 2007 | 17316752 |
| sinorhizobium meliloti psymb carries genes necessary for arabinose transport and catabolism. | arabinose is a known component of plant cell walls and is found in the rhizosphere. in this work, a previously undeleted region of the megaplasmid psymb was identified as encoding genes necessary for arabinose catabolism, by tn5-b20 random mutagenesis and subsequent complementation. transcription of this region was measured by beta-galactosidase assays of tn5-b20 fusions, and shown to be strongly inducible by arabinose, and moderately so by galactose and seed exudate. accumulation of [(3)h]arabi ... | 2007 | 17322193 |
| non-antibiotic, efficient selection for alfalfa genetic engineering. | a selectable marker gene (smg), usually conferring resistance to an antibiotic or herbicide, is generally introduced into the plant cells with the gene(s) for the trait of interest to allow only the cells that have integrated and express the foreign sequences to regenerate into a plant. the availability of several smgs for each plant species is useful for both basic and applied research to combine several genes of interest in the same plant. a selection system based on gabaculine (3-amino-2,3-di ... | 2007 | 17333020 |
| effects of diet quality on phenotypic flexibility of organ size and digestive function in mongolian gerbils (meriones unguiculatus). | in the context of evolution and ecology, there is a trade-off between the benefits of processing food through a digestive system with specific phenotypic attributes and the cost of maintaining and carrying the digestive system. in this study, we tested the hypothesis that digestive modulations at several levels can match each other to meet the energy and nutrient demands of mongolian gerbils, a small granivorous rodent species, by acclimating them to a high-quality diet diluted with alfalfa powd ... | 2007 | 17333208 |
| immunological cell and serum metabolite response of 60-week-old commercial laying hens to an alfalfa meal molt diet. | the practice of induced molting involves the restriction of light, feed removal and optionally water for 5-14 days. however, there is growing concern regarding feed removal and animal welfare issues. with this in mind, alternative diets have been developed to produce similar molting effects as that of feed deprivation. alfalfa, which largely consists of insoluble fiber, can be used as a molting diet. in this study, heterophil and lymphocyte counts, serum chemistry, and organ weight parameters we ... | 2008 | 17336056 |