Publications

the growth physics and water relations of red-light-induced germination in lettuce seeds : iii. changes in the osmotic and pressure potential in the embryonic axes of red-and far-red-treated seeds.	irradiation of grand rapids lettuce (lactuca sativa l.) seeds with red light (r) results in an increase in the growth response in the embryonic axes which enables them to overcome the mechanical restriction of the endosperm or the osmotic restriction of an external solution. when the growth rates of axes from r-and far-red(fr)-treated seeds are equalized with polyethylene-glycol-4000 solutions, a water potential difference of 3.4 bars between the axes is obtained. measurements of the osmotic pot ...	1979	24407251
the growth physics and water relations of red-light-induced germination in lettuce seeds : iv. biochemical changes in the embryonic axes of red-and far-red-treated seeds.	using lettuce (lactuca sativa l., cv. grand rapids) embryos in osmotica, we have demonstrated that when the growth rates of the embryonic axes of seeds treated with red (r) or far-red (fr) light are equalized, the axes of r-treated seeds develop a 3.4-bar decrease in water potential (paper no. iii).as axial growth begins, reserve protein and phytin decrease rapidly, concomitant with increases in reducing sugars, α-amino nitrogen, and inorganic and esterified soluble phosphates. however, no diffe ...	1979	24407252
mannanase production by the lettuce endosperm : control by the embryo.	endo-β-mannanase (ec 3.2.1.78) is produced and secreted by the cells of the endosperm of lettuce (lactuca sativa l.) "seeds" (achenes). in imbibed intact seeds, production is prevented by inhibitors. if the endosperm is incubated alone, these inhibitors can be removed by leaching, allowing mannanase production. abscisic acid, a component of lettuce seeds, inhibits the production of mannanase in the isolated endosperm, and may be involved in regulation of mannanase production in intact seeds. dur ...	1979	24407322
the role of acidification in gibberellic acid- and fusicoccin-induced elongation growth of lettuce hypocotyl sections.	the roles of gibberellic acid (ga3) and fusicoccin (fc) in the elongation growth and acidification of the medium by excised hypocotyl sections of lettuce (lactuca sativa l.) were investigated. hypocotyl sections incubated in buffer without ga3 elongate optimally at ph 4.0-4.25 while sections incubated with ga3 show the same growth between ph 4.25 and 6.0. preincubation of sections at ph 6.0 for 6 h does not affect the subsequent elongation response to acidic medium (ph 4.25); however, the sectio ...	1978	24408094
light effects upon dry lettuce seeds.	germination of certain dry "seeds" (achenes) of lactuca sativa l. cv. grand rapids was increased to ca. 75% after irradiation with 665 nm red light (r; 1x10(3) j m(-2)); this response was eliminated by far-red light (fr) following the r. the response of dry seeds required an order of magnitude more light than that of wetted seeds, and was not maximal until 48 h after irradiation. other seeds, which could not be stimulated by r in dry state, showed a partial response after 10 min hydration. irrad ...	1978	24408637
inhibitory effects of full daylight on the germination of lactuca sativa l.	using glass filters that transmit various spectral bands and different intensities of natural daylight, experiments with achenes of lettuce cv. vanquard were performed. germination during prolonged treatment depended both on the far red/red radiation ratio and on the irradiance. the promotive effect of red radiation present in natural light prevailed at low irradiances, the inhibitory effect of far red radiation at high irradiances. the dormancy imposed by prolonged white light of high intensity ...	1979	24408682
action spectra for light-induced germination in dormant lettuce seeds : i. red region.	fluence response curves for red light-induced germination of thermodormant (td) seeds of lactuca sativa l. show two regions that differ in their light sensitivity. in the region of high sensitivity, the germination responses differ between seed batches and can be altered by dark storage or far red irradiation. induction of germination in far red dormant (frd) seeds requires far higher fluences. action spectra for induction to 60% germination were determined for these various response types. spec ...	1979	24408683
action spectra for light-induced germination in dormant lettuce seeds : ii. blue region.	light of wavelengths in the range 400-500 nm induces germination of seeds of lactuca sativa l. (cv. noran and may queen) when made light requiring by high temperature (thermodormancy) or prolonged exposure to far red light (far red dormancy). td seeds proved more sensitive to blue light than frd seeds by several orders of magnitude. blue induced germination could be reversed by far red. fluence response curves for this reversion are less steep for td than for frd seeds. the degree of germination ...	1979	24408684
assessment of the possible reuse of msw coming from landfill mining of old open dumpsites.	the present study addresses the theme of recycling potential of old open dumpsites by using landfill mining. attention is focused on the possible reuse of the residual finer fraction (<4 mm), which constitutes more than 60% of the total mined material, sampled in the old open dumpsite of lavello (southern italy). we propose a protocol of analysis of the landfill material that links chemical analyses and environmental bioassays. this protocol is used to evaluate the compatibility of the residual ...	2014	24412012
degradation of the endosperm cell walls of lactuca sativa l., cv. grand rapids : timing of mobilisation of soluble sugars, lipid and phytate.	the timing of mobilisation of lipid, sucrose, raffinose and phytate in lettuce seeds (achenes) (cv. grand rapids) has been examined. these reserves (33%, 1.5%, 0.7%, 1.4% of achene dry weight, respectively) are stored mostly in the cotyledons. except for a slight degradation of raffinose and increase in sucrose, there is no detectable reserve mobilisation during germination. the endosperm (8% of seed dry weight), which has thick, mannan-containing cell walls (carbohydrate, 3,4% of seed dry weigh ...	1978	24414098
effects of colchicine and lumicolchicine on hypocotyl elongation, respiration rates and microtubules in gibberellic-acid-treated lettuce seedlings.	gibberellic-acid (ga3)-induced hypocotyl elongation of intact lettuce (lactuca sativa l.) seedlings was inhibited by colchicine (4×10(-4) m) but not by lumicolchicine (4×10(-4) m). in excised lettuce hypocotyls, ga3 (10(-5) m) increased respiration over water controls, while both colchicine and lumicolchicine alone, or in combination with ga3, reduced respiration. microtubules were present in the hypocotyls of lumicolchicine-treated seedlings but absent in those treated with colchicine. it is su ...	1978	24414274
gibberellin metabolism in excised lettuce hypocotyls: response to ga9 and the conversion of [ (3)h]ga 9.	elongation growth and gibberellin (ga9) metabolism in excised hypocotyls of lettuce (lactuca sativa l. cv. arctic) were investigated. exogenously supplied ga9 stimulates elongation of hypocotyl sections and this response is intermediate between that elicited by ga1 or ga20 and ga4/7 mixture. although uptake of radioactivity from [(3)h]ga9 increases with time, this gibberellin does not accumulate in the tissue but is rapidly converted to a compound with hplc properties resembling those of [(3)h]g ...	1978	24414470
temperature dependence of the gibberellin response in lettuce hypocotyls.	the relationship between temperature and sensitivity to gibberellin a3 (ga3) was studied in lettuce seedlings (lactuca sativa l. cv. arctic). dose/response curves for hypocotyl elongation (10(-4) mol l(-1) to 10(-8) mol l(-1)) were constructed for a range of temperatures and the slope of the linear portion of the plots used as an indication of the sensitivity to ga3. hypocotyls were unresponsive to ga3 below 13°c but above this temperature sensitivity increased linearly. plots of growth rate aga ...	1978	24414874
cell elongation and cell division in elongating lettuce hypocotyl sections.	the roles of cell division and cell elongation in the growth of sections excised from hypocotyls of lettuce (lactuca sativa l. cv. arctic) were investigated. elongation of sections incubated in the light is inhibited compared to dark-grown sections and this inhibition is reversed by gibberellic acid (ga3). the elongation of both dark-grown and ga3-treated, light-grown sections can be enhanced by 10mm kcl. under all conditions of incubation, elongation growth is greatest in the uppermost quarter ...	1977	24420091
gibberellin metabolism in excised lettuce hypocotyls: evidence for the formation of gibberellin a1 glucosyl conjugates.	the properties of the water-soluble metabolites of [(3)h]gibberellin a1 ([(3)h]ga1) from lettuce (lactuca sativa l.) hypocotyls were compared with those of authentic samples of gibberellin (ga) glucosyl esters and ethers. partitioning against l-butanol at high and low ph was not an efficient method of differentiating between ester and ether conjugates of ga1 or ga3. extraction into l-butanol at ph 2.5 was, however, useful as a group purification step. gel-filtration on acrylamide indicated a mea ...	1977	24420400
an enzyme to degrade lettuce endosperm cell walls. appearance of a mannanase following phytochrome- and gibberellin-induced germination.	lettuce seeds (lactuca sativa l. cv. grand rapids) stimulated to germinate by gibberellin and red light produce large amounts of endo-β-mannanase. this enzyme increases markedly following radicle emergence and is capable of degrading mannose-containing polysaccharides, which are the major components of the endosperm cell wall. non-germinated seeds contain little enzyme and under conditions where gibberellin- or red light-stimulated germination is prevented (eg. by abscisic acid or prolonged far ...	1976	24424598
abscisic acid as an endogenous component in lettuce fruits, lactuca sativa l. cv. grand rapids. does it control thermodormancy?	abscisic acid (aba) has been unequivocally identified as an endogenous component of seeds of grand rapids lettuce. both "free" and "bound" aba levels were followed during imbibition at various temperatures but no clear role for aba in the imposition of thermodormancy emerged. furthermore it was apparent that different seed batches showed different ratios of "free" to "bound" aba and patterns of changes. an unsuccessful attempt was made to identify "bound" aba, presumed to be the glucosyl ester.	1976	24424821
the involvement of indole acetic acid in the thermodormancy of lettuce fruits, lactuca sativa cv. grand rapids.	at 20° c and at 30° c in darkness, concentrations of indole acetic acid (iaa) greater than 10(-7) m inhibited the germination of grand rapids lettuce at 24 h and 48 h after the beginning of imbibition. there was no marked, readily defined period of inhibition during germination that could be associated solely with an effect of iaa on suppressing radicle extension. gibberellin a4+7, benzyladenine and red light were capable of reversing the effects of iaa. there was no consistent pattern of change ...	1976	24424836
a study of factors which regulate the membrane appression of lettuce thylakoids in relation to irradiance.	factors that may influence the extent of thylakoid membrane appression have been examined using lettuce (lactuca sativa cv. celtuce) grown under different irradiances. electron microscopy and salt-induced chlorophyll fluorescence suggest that the percentage of membrane appression is increased in plants grown in low light (20 wm(-2)) compared with those grown in high light (150 wm(-2)). in high light plants surface charge, as measured by 9-aminoacridine, was found to be twice that measured in low ...	1986	24442367
the structure of the lettuce endosperm.	the two-cell-layered endosperm of lettuce (lactuca sativa l.) is characterized by thick cell walls and dense cytoplasm. the periodic-acid-schiff's(pas)-positive cell wall forms numerous peg-like projections which extend into the cytoplasm. the dense cytoplasm contains organelles of protein and lipid storage. the protein bodies are numerous and appear to be interconnected by narrow extensions of their envelopes. spherosomes are also numerous; they occupy a peripheral position in the cytoplasm. ot ...	1974	24442777
changes in macrominerals, trace elements and pigments content during lettuce (lactuca sativa l.) growth: influence of soil composition.	changes in macrominerals, trace elements and photosynthetic pigments were monitored at 5 stages of lettuce growth. plants were grown in three experimental agriculture greenhouse fields (a1, a2 and a3). soil composition was also monitored to understand its influence on lettuce composition. in general, the content of macrominerals, trace elements, chlorophylls and carotenoids decreased during lettuce growth and consequently, high nutritional value was observed at younger stages. a2 lettuces showed ...	2014	24444982
photodormant lettuce seeds: phytochrome-induced protein and lipid degradation.	photodormant lettuce (lactuca sativa l.) seeds were incubated in mannitol to prevent germination. under these conditions, red light induced an extensive degradation of protein and a moderate one of lipid in the cortical cells of the radicle 24 h after treatment. it is suggested that the previously reported phytochrome-caused lowering of the water potential in light-treated embryos, which enables these embryos to overcome the resistance of the surrounding layers of the seed, is caused by lowering ...	1974	24458467
exposure studies of core-shell fe/fe(3)o(4) and cu/cuo nps to lettuce (lactuca sativa) plants: are they a potential physiological and nutritional hazard?	iron and copper nanomaterials are widely used in environmental remediation and agriculture. however, their effects on physiological parameters and nutritional quality of terrestrial plants such as lettuce (lactuca sativa) are still unknown. in this research, 18-day-old hydroponically grown lettuce seedlings were treated for 15 days with core-shell nanoscale materials (fe/fe(3)o(4), cu/cuo) at 10 and 20mg/l, and feso(4)·7h(2)o and cuso(4)·5h(2)o at 10mg/l. at harvest, fe, cu, micro and macronutri ...	2014	24462971
plant growth-promoting bacterium acinetobacter calcoaceticus p23 increases the chlorophyll content of the monocot lemna minor (duckweed) and the dicot lactuca sativa (lettuce).	acinetobacter calcoaceticus p23 is a plant growth-promoting bacterium that was isolated from the surface of duckweed (lemna aoukikusa). the bacterium was observed to colonize on the plant surfaces and increase the chlorophyll content of not only the monocotyledon lemna minor but also the dicotyledon lactuca sativa in a hydroponic culture. this effect on the lactuca sativa was significant in nutrient-poor (×1/100 dilution of h2 medium) and not nutrient-rich (×1 or ×1/10 dilutions of h2 medium) co ...	2014	24468072
a temperature-dependent source of variability in estimates of germination behaviour of lettuce fruits.	germination of fruits of lactuca sativa l. cv. "arctic king" showed a sharp upper temperature maximum at 31±1.0°c on an agar substrate in light. in a series of 60 tests carried out over 2 years, above, below and in the region of this maximum it was demonstrated that variability of germination counts was greater in the transition zone around this maximum. this is important when single controlled temperatures are chosen to compare effects of chemical or physical stresses on germination, where the ...	1973	24468990
root exudation and root development of lettuce (lactuca sativa l. cv. tizian) as affected by different soils.	development and activity of plant roots exhibit high adaptive variability. although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. to overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, wh ...	2014	24478764
inhibition of root growth by narciclasine is caused by dna damage-induced cell cycle arrest in lettuce seedlings.	narciclasine (ncs) is an amaryllidaceae alkaloid isolated from narcissus tazetta bulbs. its phytotoxic effects on plant growth were examined in lettuce (lactuca sativa l.) seedlings. results showed that high concentrations (0.5-5 μm) of ncs restricted the growth of lettuce roots in a dose-dependent manner. in ncs-treated lettuce seedlings, the following changes were detected: reduction of mitotic cells and cell elongation in the mature region, inhibition of proliferation of meristematic cells, a ...	2014	24482192
degradation of diuron by phanerochaete chrysosporium: role of ligninolytic enzymes and cytochrome p450.	the white-rot fungus phanerochaete chrysosporium was investigated for its capacity to degrade the herbicide diuron in liquid stationary cultures. the presence of diuron increased the production of lignin peroxidase in relation to control cultures but only barely affected the production of manganese peroxidase. the herbicide at the concentration of 7 μ g/ml did not cause any reduction in the biomass production and it was almost completely removed after 10 days. concomitantly with the removal of d ...	2013	24490150
absence of internalization of escherichia coli o157:h7 into germinating tissue of field-grown leafy greens.	both growth chamber and field studies were conducted to investigate the potential for escherichia coli o157:h7 to be internalized into leafy green tissue when seeds were germinated in contaminated soil. internalized e. coli o157:h7 was detected by enrichment in both spinach (spinacia oleracea l.) and lettuce (lactuca sativa l.) seedlings when seeds were germinated within the growth chamber in autoclaved and nonautoclaved soil, respectively, contaminated with e. coli o157:h7 at 2.0 and 3.8 log cf ...	2014	24490912
foliar or root exposures to smelter particles: consequences for lead compartmentalization and speciation in plant leaves.	in urban areas with high fallout of airborne particles, metal uptake by plants mainly occurs by foliar pathways and can strongly impact crop quality. however, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. in this study, two contrasting crops, lettuce (lactuca sativa l.) and rye-grass (lolium perenne l.), were exposed to pb-rich particles emitted by a pb-recycling factory via either atmospheric or soi ...	2014	24508855
impacts of major cations (k(+), na (+), ca (2+), mg (2+)) and protons on toxicity predictions of nickel and cadmium to lettuce (lactuca sativa l.) using exposure models.	biotic ligand models (blm) explicitly accounting for hypothetical interactions with biotic ligands and bioavailability as dictated by water chemistry have been developed for various metals and different organisms. it is only recently that blms for plants have received increasing attention. lettuce is one of the most important vegetable crops in the world. this study investigated the impacts of ca(2+), mg(2+), k(+), na(+) and ph, on acute toxicity of ni and cd to butter-head lettuce seedlings (la ...	2014	24510448
changes in the metabolome of lettuce leaves due to exposure to mancozeb pesticide.	this paper describes a proton high resolution magic angle spinning (hrmas) nuclear magnetic resonance (nmr) metabolomic study of lettuce (lactuca sativa l.) leaves to characterise metabolic adaptations during leaf growth and exposure to mancozeb. metabolite variations were identified through multivariate analysis and checked through spectral integration. lettuce growth was accompanied by activation of energetic metabolism, preferential glucose use and changes in amino acids, phospholipids, ascor ...	2014	24518345
temperature and other factors affecting chloramphenicol stimulation of the germination of light-sensitive lettuce seeds.	d-threo-chloramphenicol at concentrations ranging from 1000 to 3000 μg/ml stimulated the germination of the light-sensitive seeds of the lettuce (lactuca sativa l.) varieties attractie and grand rapids. this stimulatory effect of chloramphenicol was markedly temperature dependent, increasing with decrereasing temperature. seeds showed little response to chloramphenicol at temperatures of 28°c and above except in the case of light treated attractie seed. the failure of one batch of grand rapids s ...	1967	24522609
germination of lettuce induced by inhibitors of protein synthesis.	l-threo chloramphenicol and actinomycin d act like d-chloramphenicol in being able to promote germination of light-requiring seeds of lactuca sativa in darkness. the two isomers of chloramphenicol at relatively low concentrations also prevent the development of skotodormancy. protein synthesis, measured by the incorporation of tritiated leucine, occurs in dormant seeds in darkness; evidence suggests that this occurs most intensively in the endosperm. the stimulation of germination by chloramphen ...	1967	24553746
cytotoxic and phytotoxic effects of the main chemical components of spent pot-liner: a comparative approach.	spent pot-liner (spl) is a hazardous solid waste produced by the aluminum industry. although its composition may vary, fluoride and cyanide salts as well as aluminum are predominant components. a seed-germination and root-elongation test was performed with lactuca sativa seeds as a test system. spl induced decrease of seed germination rate and root elongation. the concentration of 26.5g/l spl was established from a regression curve as the ic50 (inhibition concentration 50%). through chemical ana ...	2014	24561381
exposure factors for wastewater-irrigated asian vegetables and a probabilistic rotavirus disease burden model for their consumption.	many farmers in water-scarce regions of developing countries use wastewater to irrigate vegetables and other agricultural crops, a practice that may expand with climate change. there are a number of health risks associated with wastewater irrigation for human food crops, particularly with surface irrigation techniques common in the developing world. the world health organization (who) recommends using quantitative microbial risk assessment (qmra) to determine if the irrigation scheme meets healt ...	2014	24576153
influence of the temporal and spatial variation of nitrate reductase, glutamine synthetase and soil composition in the n species content in lettuce (lactuca sativa).	the variation of nitrate reductase (nr), glutamine synthetase (gs) and n content in lettuce was evaluated at 5 stages of lettuce growth. soil physicochemical properties and its n content were also assessed to elucidate the soil-to-plant transfer of inorganic n and potential leaching to groundwater. a decrease of nr activity and an increase of no3(-) and n-kjeldahl content in lettuces were observed during plant growth, whereas gs activity and nh4(+) increased during the first few weeks of lettuce ...	2014	24576762
plastid transformation in lettuce (lactuca sativa l.) by polyethylene glycol treatment of protoplasts.	a detailed protocol for peg-mediated plastid transformation of lactuca sativa cv. flora, using leaf protoplasts, is described. successful plastid transformation using protoplasts requires a large number of viable cells, high plating densities, and an efficient regeneration system. transformation was achieved using a vector that targets genes to the trni/trna intergenic region of the lettuce plastid genome. the aada gene, encoding an adenylyltransferase enzyme that confers spectinomycin resistanc ...	2014	24599863
plastid transformation in lettuce (lactuca sativa l.) by biolistic dna delivery.	the interest in producing pharmaceutical proteins in a nontoxic plant host has led to the development of an approach to express such proteins in transplastomic lettuce (lactuca sativa l.). a number of therapeutic proteins and vaccine antigen candidates have been stably integrated into the lettuce plastid genome using biolistic dna delivery. high levels of accumulation and retention of biological activity suggest that lettuce may provide an ideal platform for the production of biopharmaceuticals.	2014	24599864
anaerobic baffled reactor coupled with chemical precipitation for treatment and toxicity reduction of industrial wastewater.	this study describes the reduction of soluble chemical oxygen demand (cods) and the removal of dissolved organic carbon (doc), formaldehyde (fa) and nitrogen from highly polluted wastewater generated during cleaning procedures in wood floor manufacturing using a laboratory-scale biological anaerobic baffled reactor followed by chemical precipitation using mgci2 .6h20 + na2hpo4. by increasing the hydraulic retention time from 2.5 to 3.7 and 5 days, the reduction rates of fa, doc and cods of nearl ...	2014	24600852
[identification of lettuce leaf nitrogen level based on adaboost and hyperspectrum].	in order to facilitate lettuce fertilization in an economically rational way, an intelligent method to identify lettuce leaf nitrogen levels was studied. lettuce samples of different nitrogen levels were cultivated in greenhouse with soilless cultivation method. in a particular growth period, the lettuce samples in various nitrogen levels were collected, then the fieldspech3 spectrometer was used to acquire the hyperspectral data of the cultivated lettuce leaves. as there were much noise and red ...	2013	24611405
mechanism of protective effect of lettuce against glucose/serum deprivation-induced neurotoxicity.	the present study investigated the protective effect of ethyl acetate fraction of lettuce (lactuca sativa) against glucose/serum deprivation (gsd)-induced neurotoxicity, a model which simulates neuronal damage during ischemia.	2015	24621063
4',4‴,7,7″-tetra-o-methylcupressuflavone inhibits seed germination of lactuca sativa.	biflavonoids have been isolated from a wide variety of plant species, but little is known about their native biological functions. here we report a possible ecological role for biflavonoids by describing the isolation of the biflavonoid 4',4‴,7,7″-tetra-o-methylcupressuflavone (1) from araucaria columnaris and its inhibitory effect on seed germination. compound 1 was isolated from needles of a single a. columnaris specimen and inhibited germination of lactuca sativa seeds in a culture-dish assay ...	2014	24628372
development and phytochemical characterization of high polyphenol red lettuce with anti-diabetic properties.	polyphenol-rich rutgers scarlet lettuce (rsl) (lactuca sativa l.) was developed through somaclonal variation and selection in tissue culture. rsl may contain among the highest reported contents of polyphenols and antioxidants in the category of common fruits and vegetables (95.6 mg/g dry weight and 8.7 mg/g fresh weight gallic acid equivalents and 2721 µmol/g dry weight and 223 µmol/g fresh weight trolox equivalents). three main compounds accumulate at particularly high levels in rsl: chlorogeni ...	2014	24637790
influence of green, red and blue light emitting diodes on multiprotein complex proteins and photosynthetic activity under different light intensities in lettuce leaves (lactuca sativa l.).	the objective of this study was to investigate the response of light emitting diodes (leds) at different light intensities (70 and 80 for green leds, 88 and 238 for red leds and 80 and 238 μmol m-2 s-1 for blue leds) at three wavelengths in lettuce leaves. lettuce leaves were exposed to (522 nm), red (639 nm) and blue (470 nm) leds of different light intensities. thylakoid multiprotein complex proteins and photosynthetic metabolism were then investigated. biomass and photosynthetic parameters in ...	2014	24642884
phytotoxic substances with allelopathic activity may be central to the strong invasive potential of brachiaria brizantha.	the grass brachiaria brizantha, native to eastern africa, becomes naturalized and dominant quickly in the non-native areas. it was hypothesized that phytotoxic chemical interaction between this plant and native plants may play an important role in the invasion of b. brizantha. however, no potent phytotoxic substance has been reported in this species. therefore, we investigated possible allelopathic activity and searched for phytotoxic substances with allelopathic activity in b. brizantha. an aqu ...	2014	24655388
effects of jatropha curcas oil in lactuca sativa root tip bioassays.	jatropha curcas l. (euphorbiaceae) is important for biofuel production and as a feed ingredient for animal. however, the presence of phorbol esters in the oil and cake renders the seeds toxic. the toxicity of j. curcas oil is currently assessed by testing in animals, leading to their death. the identification of toxic and nontoxic improved varieties is important for the safe use of j. curcas seeds and byproducts to avoid their environmental toxicity. hence, the aim of this study was to propose a ...	2014	24676174
insecticide residues in head lettuce, cabbage, chinese cabbage, and broccoli grown in fields.	the residues of four insecticides belonging to different families were studied on head lettuce (lactuca sativa l. var. capitata l.), cabbage (brassica oleracea linn. var. capitata dc.), chinese cabbage (brassica pekinensis skeels), and broccoli (brassica oleracea var. italica) after pesticide application. to reduce application variability, a tank mix of acetamiprid 20% sp, chlorpyrifos 22.5% ec, deltamethrin 2.4% sc, and methomyl 40% sp was applied at recommended and double doses. initial deposi ...	2014	24684565
comparative analysis of complete chloroplast genome sequence and inversion variation in lasthenia burkei (madieae, asteraceae).	complete chloroplast genome studies can help resolve relationships among large, complex plant lineages such as asteraceae. we present the first whole plastome from the madieae tribe and compare its sequence variation to other chloroplast genomes in asteraceae.	2014	24699541
impact of non-functionalized and amino-functionalized multiwall carbon nanotubes on pesticide uptake by lettuce (lactuca sativa l.).	the effect of non-functionalized and amino-functionalized multiwall carbon nanotube (cnt) exposure, as well as the impact of cnt presence on coexistent pesticide accumulation, was investigated in lettuce (lactuca sativa l.). lettuce seeds were sown directly into cnt-amended vermiculite (1000 mg l(-1)) to monitor phytotoxicity during germination and growth. during growth, lettuce seedlings were subsequently exposed to chlordane (cis-chlordane [cs], trans-chlordane [tc] and trans-nonachlor [tn]) a ...	2015	24716640
landfill wall revegetation combined with leachate recirculation: a convenient procedure for management of closed landfills.	there is a need for a reliable sustainable option to effectively manage the landfill leachate generation. this study presents a simple procedure for the revegetation of the walls of closed landfills, employing the leachate as a fertirrigant. the native plants lepidium sativum, lactuca sativa, and atriplex halimus, which suit the local climate, were chosen for this study in southern italy. the methodology was structured into three phases (i) early stage toxicity assessment phase (apical root leng ...	2014	24737024
effects of nitrogen fertilizers on the growth and nitrate content of lettuce (lactuca sativa l.).	nitrogen is an essential element for plant growth and development; however, due to environmental pollution, high nitrate concentrations accumulate in the edible parts of these leafy vegetables, particularly if excessive nitrogen fertilizer has been applied. consuming these crops can harm human health; thus, developing a suitable strategy for the agricultural application of nitrogen fertilizer is important. organic, inorganic, and liquid fertilizers were utilized in this study to investigate thei ...	2014	24758896
assessment of microbiological contamination of fresh, minimally processed, and ready-to-eat lettuces (lactuca sativa), rio de janeiro state, brazil.	this study aimed to assess the microbiological contamination of lettuces commercialized in rio de janeiro, brazil, in order to investigate detection of norovirus genogroup ii (nov gii), salmonella spp., total and fecal coliforms, such as escherichia coli. for nov detection samples were processed using the adsorption-elution concentration method associated to real-time quantitative polymerase chain reaction (qpcr). a total of 90 samples of lettuce including 30 whole fresh lettuces, 30 minimally p ...	2014	24761806
nitrate content in dandelion (taraxacum officinale) and lettuce (lactuca sativa) from organic and conventional origin: intake assessment.	to estimate the actual intake of nitrate by consumption of different lettuce varieties, 52 samples of lettuce of different origins and dandelion from 15 different areas of northeast slovenia were analysed. for determination of actual nitrate content, a continuous flow method was used. the lowest nitrate content was detected in dandelion, with a mean value of 195 mg kg(-1) (ranging 47-487 mg kg(-1)). nitrate content in lettuce of different origins ranged 85-3237 mg kg(-1), with a mean value of 11 ...	2012	24779737
effect of the soil type on the microbiome in the rhizosphere of field-grown lettuce.	the complex and enormous diversity of microorganisms associated with plant roots is important for plant health and growth and is shaped by numerous factors. this study aimed to unravel the effects of the soil type on bacterial communities in the rhizosphere of field-grown lettuce. we used an experimental plot system with three different soil types that were stored at the same site for 10 years under the same agricultural management to reveal differences directly linked to the soil type and not i ...	2014	24782839
allelopathic activity and chemical constituents of walnut (juglans regia) leaf litter in walnut-winter vegetable agroforestry system.	walnut agroforestry systems have many ecological and economic benefits when intercropped with cool-season species. however, decomposing leaf litter is one of the main sources of allelochemicals in such systems. in this study, lettuce (lactuca sativa var. angustata) was grown in the soil incorporated with walnut leaf litter to assess its allelopathic activity. lettuce growth and physiological processes were inhibited by walnut leaf litter, especially during early growth stage (1-2 euphylla period ...	2014	24784929
the impact of the pathogen rhizoctonia solani and its beneficial counterpart bacillus amyloliquefaciens on the indigenous lettuce microbiome.	lettuce belongs to the most commonly raw eaten food worldwide and its microbiome plays an important role for both human and plant health. yet, little is known about the impact of potentially occurring pathogens and beneficial inoculants of the indigenous microorganisms associated with lettuce. to address this question we studied the impact of the phytopathogenic fungus rhizoctonia solani and the biological control agent bacillus amyloliquefaciens fzb42 on the indigenous rhizosphere and phyllosph ...	2014	24795707
effect of aqueous and hydro-alcoholic extracts of lettuce (lactuca sativa) seed on testosterone level and spermatogenesis in nmri mice.	one of the considerable uses of lettuce (lactuca sativa) seed in traditional medicine has been to reduce semen, sperm and sexuality.	2014	24799863
retention of iceberg lettuce quality by low temperature storage and postharvest application of 1-methylcyclopropene or gibberellic acid.	this study was conducted to evaluate the changes in quality of iceberg lettuce during storage at different temperatures and the effects of postharvest treatments of 1-methylcyclopropene or gibberellic acid at high temperature. the results showed that quality of the lettuce was remarkably retained during storage at 0 °c, but significantly declined at 20 °c. however, quality of the vegetable at shelf-temperature (20 °c, 85 ~ 95% rh) was effectively delayed by the treatment with 1-methylcyclopropen ...	2014	24803702
searching the best equilibrium moisture equation for lettuce seeds using measures of curvature and bias.	in the present work, we performed a discrimination analysis of the nonlinear equations used to describe sorption isotherms of the lettuce seeds. the equilibrium data were obtained by the static method using saturated salt solutions. the best model to describe the equilibrium moisture of lettuce seeds was selected using measures of curvature and bias. the obtained results showed that the copace equation was the best model in terms of nonsignificance for bias and nonlinearity measures.	2013	24804051
production of an endoinulinase from aspergillus niger aumc 9375, by solid state fermentation of agricultural wastes, with purification and characterization of the free and immobilized enzyme.	two different substrates, sunflower (helianthus annuus l.) tubers and lettuce (lactuca sativa) roots, were tested. using a mixture of both wastes resulted in higher production of endoinulinase than either waste alone. also, ten fungal species grown on these substrates as inexpensive, carbon sources were screened for the best production of endoinulinase activities. of these, aspergillus niger aumc 9375 was the most productive, when grown on the mixture using a 6:1 w/w ratio of sun flower: lettuce ...	2014	24810318
toxicity assessment through multiple endpoint bioassays in soils posing environmental risk according to regulatory screening values.	toxicity profiles of two soils (a brownfield in legazpi and an abandoned iron mine in zugaztieta; basque country) contaminated with several metals (as, zn, pb and cu in legazpi; zn, pb, cd and cu in zugaztieta) and petroleum hydrocarbons (in legazpi) were determined using a multi-endpoint bioassay approach. investigated soils exceeded screening values (svs) of regulatory policies in force (basque country; europe). acute and chronic toxicity bioassays were conducted with a selected set of test sp ...	2014	24819436
delineating ion-ion interactions by electrostatic modeling for predicting rhizotoxicity of metal mixtures to lettuce lactuca sativa.	effects of ion-ion interactions on metal toxicity to lettuce lactuca sativa were studied based on the electrical potential at the plasma membrane surface (ψ0 ). surface interactions at the proximate outside of the membrane influenced ion activities at the plasma membrane surface ({m(n+)}0). at a given free cu(2+) activity in the bulk medium ({cu(2+)}b), additions of na(+), k(+), ca(2+), and mg(2+) resulted in substantial decreases in {cu(2+)}0. additions of zn(2+) led to declines in {cu(2+)}0, b ...	2014	24863101
[emission of ch4, n2o and nh3 from vegetable field applied with animal manure composts].	greenhouse gas (ghg) emission from vegetable land is of great concern recently because agriculture land is one of the major sources contributing to global ghg emission. in this study, an experiment of lactuca sativa l. land applied with different animal manure composts was carried out in a greenhouse vegetable land located in the surburb of beijing to monitor the emission of ghg (ch4 and n2o) and ammonia in situ, and to analyze the affecting factors of ghg and ammonia emission. results showed th ...	2014	24881375
effect of the strain bacillus amyloliquefaciens fzb42 on the microbial community in the rhizosphere of lettuce under field conditions analyzed by whole metagenome sequencing.	application of the plant associated bacterium bacillus amyloliquefaciens fzb42 on lettuce (lactuca sativa) confirmed its capability to promote plant growth and health by reducing disease severity (ds) caused by the phytopathogenic fungus rhizoctonia solani. therefore this strain is commercially applied as an eco-friendly plant protective agent. it is able to produce cyclic lipopeptides (clp) and polyketides featuring antifungal and antibacterial properties. production of these secondary metaboli ...	2014	24904564
phytotoxic steroidal saponins from agave offoyana leaves.	a bioassay-guided fractionation of agave offoyana leaves led to the isolation of five steroidal saponins (1-5) along with six known saponins (6-11). the compounds were identified as (25r)-spirost-5-en-2α,3β-diol-12-one 3-o-{α-l-rhamnopyranosyl-(1→3)-o-β-d-glucopyranosyl-(1→2)-o-[β-d-xylopyranosyl-(1→3)]-o-β-d-glucopyranosyl-(1→4)-o-β-d-galactopyranoside} (1), (25r)-spirost-5-en-3β-ol-12-one 3-o-{α-l-rhamnopyranosyl-(1→3)-o-β-d-glucopyranosyl-(1→2)-o-[β-d-xylopyranosyl-(1→3)]-o-β-d-glucopyranosyl ...	2014	24939800
acclimation to uv-b radiation and visible light in lactuca sativa involves up-regulation of photosynthetic performance and orchestration of metabolome-wide responses.	uv-b radiation is often viewed as a source of stress for higher plants. in particular, photosynthetic function has been described as a common target for uv-b impairment; yet as our understanding of uv-b photomorphogenesis increases, there are opportunities to expand the emerging paradigm of regulatory uv response. lactuca sativa is an important dietary crop species and is often subjected to rapid sunlight exposure at field transfer. acclimation to uv-b and visible light conditions in l. sativa w ...	2015	24945714
capture and accumulation of perchlorate in lettuce. effect of genotype, temperature, perchlorate concentration, and competition with anions.	various studies have evaluated the accumulation of clo4(-) in lettuce (lactuca sativa), but very few have dealt with the variables that can interfere with its capture. the present study evaluates the transfer of clo4(-) in two l. sativa varieties: butter head (l. sativa var. capitata) and cos lettuce (l. sativa var. crispa) under hydroponic conditions. the clo4(-) concentrations used correspond to levels (1 and 2mgl(-1)), measured in irrigation water in the iquique region in the north of chile. ...	2014	24997918
invasive plant-derived biochar inhibits sulfamethazine uptake by lettuce in soil.	veterinary antibiotics are frequently detected in soils posing potential contamination of food crops. sulfamethazine (smt) uptake was investigated by lettuce (lactuca sativa l.) grown in the soils treated with/without biochar derived from an invasive plant, burcucumber (sicyos angulatus l.) (bbc700). soils were contaminated with smt at 5 and 50mgkg(-1), and treated with/without 5% bbc700 (ww(-1)). the lettuces were harvested after 5weeks of cultivation and were analyzed for smt by a high perform ...	2014	24997958
led lighting and seasonality effects antioxidant properties of baby leaf lettuce.	we report on the application of supplementary light-emitting diode (led) lighting within a greenhouse for cultivation of red, green and light green leaf baby lettuces (lactuca sativa l.) grown under natural illumination and high-pressure sodium (hps) lamps (16-h; ppfd-170 μmol m(-2)s(-1)) during different growing season. supplementary lighting from blue 455/470 nm and green 505/530 nm leds was applied (16-h; ppfd-30 μmol m(-2)s(-1)). our results showed that to achieve solely a positive effect is ...	2012	25005972
use of propolis in the sanitization of lettuce.	the present study aimed to determine the effectiveness of propolis in reducing the microbial load in ready-to-eat (rte) and fresh whole head (fwh) lettuces (lactuca sativa l.) type batavia. two sanitizing solutions were employed: sodium hypochlorite (sh) and propolis (ps), during 15 and 30 min. tap water (tw) was used as a control. regarding the mean reduction on aerobic mesophiles, psychrotrophic and fecal coliforms, the sh and ps treatments showed the same pattern of variation. in all cases, p ...	2014	25007823
phosphate/zinc interaction analysis in two lettuce varieties reveals contrasting effects on biomass, photosynthesis, and dynamics of pi transport.	inorganic phosphate (pi) and zinc (zn) are essential nutrients for normal plant growth. interaction between these elements has been observed in many crop plants. despite its agronomic importance, the biological significance and genetic basis of this interaction remain largely unknown. here we examined the pi/zn interaction in two lettuce (lactuca sativa) varieties, namely, "paris island cos" and "kordaat." the effects of variation in pi and zn supply were assessed on biomass and photosynthesis f ...	2014	25025059
phytotoxic activity of ocimum tenuiflorum extracts on germination and seedling growth of different plant species.	phytotoxic activity of ocimum tenuiflorum (lamiaceae) plant extracts was investigated against the germination and seedling growth of cress (lepidium sativum), lettuce (lactuca sativa), alfalfa (medicago sativa), italian ryegrass (lolium multiflorum), barnyard grass (echinochloa crus-galli), and timothy (phleum pratense) at four different concentrations. the plant extracts at concentrations greater than 30 mg dry weight equivalent extract ml(-1) reduced significantly the total germination percent ...	2014	25032234
trichoderma spp. alleviate phytotoxicity in lettuce plants (lactuca sativa l.) irrigated with arsenic-contaminated water.	the influence of two strains of trichoderma (t. harzianum strain t22 and t. atroviride strain p1) on the growth of lettuce plants (lactuca sativa l.) irrigated with as-contaminated water, and their effect on the uptake and accumulation of the contaminant in the plant roots and leaves, were studied. accumulation of this non-essential element occurred mainly into the root system and reduced both biomass development and net photosynthesis rate (while altering the plant p status). plant growth-promo ...	2014	25046759
comparing three approaches in extending biotic ligand models to predict the toxicity of binary metal mixtures (cu-ni, cu-zn and cu-ag) to lettuce (lactuca sativa l.).	metals are always found in the environment as mixtures rather than as solitary elements. however, effect models such as biotic ligand models (blms) are usually derived for toxicity prediction of single metals. our study aimed at predicting mixture toxicity of cu-ni, cu-zn and cu-ag combinations to lettuce (lactucasativa l.) by combining blms with three toxicity indexes: the toxic unit, the overall amounts of metal ions bound to the biotic ligands and the toxic equivalency factor. the accumulatio ...	2014	25048917
comparative study of toxicity of azo dye procion red mx-5b following biosorption and biodegradation treatments with the fungi aspergillus niger and aspergillus terreus.	azo dyes are an important class of environmental contaminants and are characterized by the presence of one or more azo bonds (-n=n-) in their molecular structure. effluents containing these compounds resist many types of treatments due to their molecular complexity. therefore, alternative treatments, such as biosorption and biodegradation, have been widely studied to solve the problems caused by these substances, such as their harmful effects on the environment and organisms. the aim of the pres ...	2014	25048922
an analysis of electrical impedance measurements applied for plant n status estimation in lettuce (lactuca sativa).	nitrogen plays a key role in crop yields. hence, farmers may apply excessive n fertilizers to crop fields, inducing environmental pollution. crop n monitoring methods have been developed to improve n fertilizer management, most of them based on leaf or canopy optical-property measurements. however, sensitivity to environmental interference remains an important drawback. electrical impedance has been applied to determine the physiological and nutritional status of plant tissue, but no studies rel ...	2014	25057134
phytochemical relationship of euphorbia helioscopia and euphorbia pulcherrima with lactuca sativa.	allelopathy is an important phenomenon that modifies the ecosystem. a plant can enhance or reduce the growth of other plant due to the presence of a number of allelochemicals in its different parts. euphorbia helioscopia and euphorbia pulcherrima are medicinal plant species. both these species are collected from wild resources for various purposes. to reduce the pressure on wild population, it is important to bring them into cultivation. therefore, the allelopathic effects of e. helioscopia and ...	2014	25075544
[effects of led spectrum combinations on the absorption of mineral elements of hydroponic lettuce].	lettuce (lactuca sativa) was hydroponically cultured in a completely enclosed plant factory, in which spectrum proportion-adjustable led panels were used as sole light source for plant growth. absorption and content of eleven mineral elements such as k, p, ca, mg, na, fe, mn, zn, cu, b and mo in lactuca sativa under different spectral component conditions were studied by icp -aes technology. the results showed that: (1) single or combined spectrums corresponding to the absorbing peaks of chlorop ...	2014	25095445
particle size characterization of oak wood leachate: chemical oxygen demand and toxicity distribution within different fractions.	oak wood leachate obtained from two storage facilities (storage pound and ditch) in a wood-based industry, and leachate generated by a laboratory leaching test, were characterized in seven categories regarding particle size distribution (psd) (raw leachate, ≤ 20 μm, ≤ 10 μm, ≤ 1.2 μm, ≤ 13 nm, ≤ 5 nm and ≤ 2 nm). the psd followed a normal distribution model with a correlation coefficient (r) varying from 82 to 88. each fraction was analysed regarding chemical oxygen demand, polyphenols and acute ...	2014	25098881
salt stress mitigation by seed priming with uv-c in lettuce plants: growth, antioxidant activity and phenolic compounds.	seeds of lactuca sativa l. 'romaine' were subjected to priming treatments with uv-c radiation at 0.85 or 3.42 kj m(-2). seedlings obtained from both primed (pr) and non-primed (npr) seeds were grown in an hydroponic culture system supplemented with 0 (control) or 100 mm nacl. after 21 days of nacl treatment, root and leaf biomass, root lengths, leaf numbers, and leaf surface area were measured. ions (na(+) and k(+)) accumulation was determined in roots and leaves. total phenolic compound and fla ...	2014	25133899
ecotoxicological and genotoxic assessment of hospital laundry wastewaters.	the aim of the present study was to assess the ecotoxicity and genotoxicity of hospital laundry wastewaters generated from a regional hospital located in rio pardo valley in the state of rio grande do sul, brazil. physicochemical, microbiological, ecotoxicological, and genotoxic analyses were performed, and the results indicate that some parameters were not in accordance with the limit concentrations established by brazilian and international guidelines for urban wastewaters. daphnia magna (ec50 ...	2015	25135422
evaluating darwin's naturalization hypothesis in experimental plant assemblages: phylogenetic relationships do not determine colonization success.	darwin's naturalization hypothesis (dnh) proposes that colonization is less likely when the colonizing species is related to members of the invaded community, because evolutionary closeness intensifies competition among species that share similar resources. studies that have evaluated dnh from correlational evidence have yielded controversial results with respect to its occurrence and generality. in the present study we carried out a set of manipulative experiments in which we controlled the phy ...	2014	25141013
relationships between nuclear magnetic resonance parameters used to characterize weathering spilled oil and soil toxicity in central patagonia.	oil spill in the central patagonian zone was studied to evaluate if any relationship exists between the parameters used to characterize weathering spilled oil and soil toxicity for two plant species and to evaluate if the phytotoxicity to local species would be a good index for the soil contamination. nuclear magnetic resonance (nmr) structural indexes and column chromatography compositional indexes were determined to characterize the oil spill in the soil samples. bioassays were also carried ou ...	2017	25145179
chemical composition and phytotoxic effects of essential oils obtained from ailanthus altissima (mill.) swingle cultivated in tunisia.	ailanthus altissima mill. swingle (simaroubaceae), also known as tree of heaven, is used in the chinese traditional medicine as a bitter aromatic drug for the treatment of colds and gastric diseases. in tunisia, ailanthus altissima is an exotic tree, which was introduced many years ago and used particularly as a street ornamental tree. here, the essential oils of different plant parts of this tree, viz., roots, stems, leaves, flowers, and samaras (ripe fruits), were obtained by hydrodistillation ...	2014	25146765
evaluation of anti-inflammatory activity and fast uhplc-dad-it-tof profiling of polyphenolic compounds extracted from green lettuce (lactuca sativa l.; var. maravilla de verano).	fresh cut vegetables represent a widely consumed food worldwide. among these, lettuce (lactuca sativa l.) is one of the most popular on the market. the growing interest for this "healthy" food is related to the content of bioactive compounds, especially polyphenols, that show many beneficial effects. in this study, we report the anti-inflammatory and antioxidant potential of polyphenols extracted from lettuce (var. maravilla de verano), in j774a.1 macrophages stimulated with escherichia coli lip ...	2015	25148972
contact sensitization to lettuce and rocket-salad with and without systemic elicitation of dermatitis after oral challenge.		2014	25155079
selected biochemical properties of polyphenol oxidase in butter lettuce leaves (lactuca sativa l. var. capitata) elicited with dl-β-amino-n-butyric acid.	the study concentrated on changes in certain biochemical parameters of polyphenol oxidase (ppo) from lettuce leaves caused by dl-β-amino-n-butyric acid (baba) elicitation. ppo from control plants demonstrated the highest affinity toward catechol, whereas ppo from baba-elicited lettuce showed the highest affinity to 4-methylcatechol. the optimum temperature for enzymes from control plants was 35°c, whereas from plants elicited with 1mm baba this was 25°c. ppo from plants elicited with baba was al ...	2015	25172730
climate warming may facilitate invasion of the exotic shrub lantana camara.	plant species show different responses to the elevated temperatures that are resulting from global climate change, depending on their ecological and physiological characteristics. the highly invasive shrub lantana camara occurs between the latitudes of 35 °n and 35 °s. according to current and future climate scenarios predicted by the climex model, climatically suitable areas for l. camara are projected to contract globally, despite expansions in some areas. the objective of this study was to te ...	2014	25184224
partial aphid resistance in lettuce negatively affects parasitoids.	this study investigated the effects of partial plant resistance on the lettuce aphid nasonovia ribisnigri (mosley) (hemiptera: aphididae), a major pest of cultivated lettuce (lactuca sativa l.), and one of its parasitoids, aphidius ervi haliday (hymenoptera: braconidae). aphids were reared on susceptible (l. sativa variety estival; s) or partially resistant (lactuca serriola l. pi 491093; pr) lettuce, and next parasitized by a. ervi females. fitness proxies were measured for both aphids and para ...	2014	25197882
role of gsh homeostasis under zn toxicity in plants with different zn tolerance.	tripepthide glutathione (gsh) is a pivotal molecule in tolerance to heavy metals, including zinc (zn). the aim of our work is to examine the role of gsh metabolism in two different horticultural plants under zn toxicity in order to select and/or generate plants tolerant to zn toxicity. we show a comparative analysis of the toxic effect of 0.5mm zn between lactuca sativa cv. phillipus and brassica oleracea cv. bronco. in l. sativa the accumulation of zn resulted in an increase in reactive oxygen ...	2014	25219313
valorization of essential oils from moroccan aromatic plants.	the chemical composition and biological activity of cultivated and wild medicinal and aromatic plants from morocco (artemisia herba-alba, lippia citriodora, mentha pulegium, m. spicata, myrtus communis, rosmarinus officinalis, and thymus satureioides) are described. the essential oils (eos) of these species have been analyzed by gc-ms. the antifeedant, nematicidal and phytotoxic activities of the eos were tested on insect pests (spodoptera littoralis, myzus persicae and rhopalosiphum padi), root ...	2014	25233584
phytotoxic action of naphthoquinone juglone demonstrated on lettuce seedling roots.	juglone, 5-hydroxy-1,4-naphthoquinone, is the plant secondary metabolite with allelopathic properties, which was isolated especially from the plant species belonging to family juglandaceae a. rich. ex kunth (walnut family). the mechanism of phytotoxic action of juglone was investigated on lettuce seedlings lactuca sativa l. var. capitata l. cv. merkurion by determining its effect at different levels. we have found that juglone inhibits mitosis (mitotic index 8.5 ± 0.6% for control versus 2.2 ± 0 ...	2014	25240266
water-soluble compounds of lettuce inhibit dna damage and lipid peroxidation induced by glucose/serum deprivation in n2a cells.	oxidative stress, increase of lipid peroxidation and resultant dna damage are associated with pathophysiology of many human diseases such as acute and chronic cns injuries and diseases, cancer, and also aging. this work was done to investigate whether water fraction from the hydroalcoholic extract of green leaf lettuce (lactuca sativa l.) can protect n2a cells against glucose/serum deprivation (gsd)-induced lipid peroxidation and dna fragmentation. the cells were cultivated for 12 h in gsd condi ...	2014	25265820
evaluation of lettuce germplasm resistance to gray mold disease for organic cultivations.	this study was conducted to evaluate the resistance of 212 accessions of lettuce germplasm to gray mold disease caused by botrytis cinerea. the lettuce germplasm were composed of five species: lactuca sativa (193 accessions), l. sativa var. longifolia (2 accessions), l. sativa var. crispa (2 accessions), l. saligna (2 accessions), and l. serriola (1 accession); majority of these originated from korea, netherlands, usa, russia, and bulgaria. after 35 days of spray inoculation with conidial suspen ...	2014	25288990
host genotype and hypersensitive reaction influence population levels of xanthomonas campestris pv. vitians in lettuce.	dynamics of population sizes of xanthomonas campestris pv. vitians inoculated onto or into lettuce leaves were monitored on susceptible and resistant cultivars. in general, population growth was greater for susceptible (clemente, salinas 88, vista verde) than resistant (batavia reine des glaces, iceberg, little gem) cultivars. when spray-inoculated or infiltrated, population levels of x. campestris pv. vitians were consistently significantly lower on little gem than on susceptible cultivars, whi ...	2015	25302523
emergence of groundnut ringspot virus and tomato chlorotic spot virus in vegetables in florida and the southeastern united states.	groundnut ringspot virus (grsv) and tomato chlorotic spot virus (tcsv) are two emerging tospoviruses in florida. in a survey of the southeastern united states, grsv and tcsv were frequently detected in solanaceous crops and weeds with tospovirus-like symptoms in south florida, and occurred sympatrically with tomato spotted wilt virus (tswv) in tomato and pepper in south florida. tswv was the only tospovirus detected in other survey locations, with the exceptions of grsv from tomato (solanum lyco ...	2015	25317844
[ecotoxicological effect and soil environmental criteria of the heavy metal chromium(vi)].	nowadays, systematic studies about water quality criteria are being carried out in china, but studies on soil environmental criteria are comparatively insufficient. in this study, germination and root growth of 8 terrestrial plants (triticum aestivum, lactuca sativa, cucumis sativus, zea mays, brassica pekinensis, glycine max, allium tuberosum and solanum lycopersicum) and growth inhibition of 1 terrestrial animal (achatina fulica) were used to determine the chronic ecotoxicological effects of c ...	2014	25338393
growing patterns to produce 'nitrate-free' lettuce (lactuca sativa).	vegetables can contain significant amounts of nitrate and, therefore, may pose health hazards to consumers by exceeding the accepted daily intake for nitrate. different hydroponic growing patterns were examined in this work in order to obtain 'nitrate-free lettuces'. growing lettuces on low nitrate content nutrient solution resulted in a significant decrease in lettuces' nitrate concentrations (1741 versus 39 mg kg(-1)), however the beneficial effect was cancelled out by an increase in the ambie ...	2015	25345876
characterization of cytochalasins from the endophytic xylaria sp. and their biological functions.	bioassay-guided fractionation of the fermentation extract of xylaria sp. xc-16, an endophyte from toona sinensis led to the isolation of two new cytochalasans cytochalasin z27, 1, and cytochalasin z28, 2, along with three known compounds seco-cytochalasin e, 3, and cytochalasin z18, 4, and cytochalasin e, 5. the structures of 1 and 2 were elucidated by spectroscopic and electronic circular dichroism methods. compound 5 was shown to be potently cytotoxic against brine shrimp (lc50 = 2.79 μm), com ...	2014	25350301