Plants Of Biotype Research Articles

Структура сорта масличного льна Ы 117 на основе полиморфных микросателлитных локусов

Oil flax is a high-demand highly profitable crop. The modern standards of breeding and seed growing expect to the genetic passportization of the breeding achievement. Microsatellite sequences of DNA are an effective instrument to conduct the passportization of the genetic material. Oil flax cultivars self-pollinators are known to be able to possess the intravarietal heterogeneity. That’s why using a system of microsatellite DNA-markers, we estimated the genetic structure of the cultivar Y 117 of oil flax bred at the V.S. Pustovoit All-Russian Research Institute of Oil Crops. The estimation of the genetic structure was conducted in a series of 40 plants. We used 16 microsatellite markers in our work. The analysis of PCR products showed the series of plants is homogenous by 13 loci. Loci Lu3, Lu21, and Lu27b had two alleles. The analysis by three polymorphic loci of allele state of the separate plants of the cultivar reviled four groups of plants having a different type of allele combination (biotypes): A (Lu3175Lu21´109 Lu27b135), B (Lu3166Lu21´117Lu27b142), C (Lu3166Lu21´109Lu27b135), and D (Lu3175,166Lu21´109 Lu27b135) with a frequency of 57.5%, 37.5, 2.5, and 2.5%, respectively. Our results certifies that the cultivar Y 117 can be considered as a complex of biotypes. The main biotypes A and B totally reach 95% of the series. The biotypes D and C (totally 5% of the series) possibly are a result of pollination between plants of biotypes A and B. In a view of origin of this cultivar from some unique by the resistance to flax sickness plants, the amount of reviled biotypes is little. However taking in to attention an admissible level of allogamy within a cultivar, with time a shift in a combination of biotypes and some increase in their amount is possible. The combination of biotypes can be used as a parameter to control the stability of a cultivar, which is one of the definitive criteria of a cultivar according to the requirements of the International Union for the Protection of New Varieties of Plants (UPOV).

Variability of development of barley plants of biotypes depending on the seeding time and seeding rates

Variability of development of barley plants of biotypes depending on the seeding time and seeding rates

Analysis of Camelina sativa transcriptomes identified specific transcription factors and processes associated with freezing tolerance in a winter biotype

Camelina (Camelina sativa L., Crantz) is an oilseed crop consisting of both spring- and winter-biotypes. Winter biotypes of camelina need a low-temperature treatment to acquire freezing tolerance and floral competence. However, spring biotypes do not require a low-temperature treatment to initiate flowering and do not cold acclimate to the same extent as winter biotypes. Exposure of the camelina winter biotype ‘Joelle’ to low temperature (5 °C) for 0-, 1-, 2-, 4-, and 6-weeks resulted in freezing survival rates of ~ 0%, 0%, 20%, 36%, and 72%, respectively, after being exposed to freezing conditions (−15 °C for 4 h). Winter biotype plants that survived the freezing treatment (42 d post-treatment under greenhouse conditions) also flowered; however, time to flowering was dependent on the cold treatment duration. Plants exposed to 5 °C for six weeks flowered first followed in order by plants exposed to 4- and 2-weeks cold. To decipher molecular regulation associated with low-temperature acquired freezing tolerance and floral competence in camelina, we analyzed the transcriptomes of a spring biotype (CO46) and winter biotype (Joelle) exposed to 0-, 1-, 2-, 4-, 6- and 8-weeks low temperature (5 °C). Genes and transcription factors with significant differential abundance (4-fold up or down) in the winter- compared to the spring-biotype of camelina were used to identify those over-represented among gene ontologies. The results highlighted gene ontologies associated with abiotic and biotic defense responses, oxidative stress responses, cell wall modification and cell expansion, biosynthesis of very long chain fatty acids and anthocyanins, as well as processes involving photosynthesis, sugar metabolism, transport, and phytohormone (abscisic acid, auxin, jasmonic acid, and salicylic acid) signaling. Transcripts associated with these processes in the winter biotype of camelina may be regulated by transcription factors similar to Arabidopsis MYB47, MYB75, MYB90, NF-YA4 and NF-YB2, HAT1, GRF7, CKG, and CBF1 and CBF2.

First Report of Glyphosate-Resistant Biotype of Eleusine Indica (L.) Gaertn. in Europe

Glyphosate-resistant biotypes of Eleusine indica (L.) Gaertn. have been detected in Asia, the Americas but not in Europe. The aim of this study was to evaluate resistance levels and possible target site resistance mechanisms of an E. indica biotype (19-1) collected from a plant nursery in Southern Italy where poor glyphosate efficacy was reported. Two dose-response experiments were conducted to evaluate the sensitivity of biotype 19-1 to glyphosate in comparison with two susceptible checks. 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) sequencing was performed to identify possible mutations conferring the resistance. The susceptible biotypes were completely controlled at the glyphosate recommended field dose of 360 g ae ha−1, while 50% of the plants of biotype 19-1 survived at 1440 g ae ha−1. The resistance index of biotype 19-1 ranged between 5.8 and 7.3 for the response variables of fresh weight reduction and plant survival, respectively. All the plants surviving glyphosate application and sampled for DNA analyses had the point mutation P106A. The biotype 19-1 can be confirmed as glyphosate-resistant, representing the first glyphosate-resistant population of E. indica in Europe.

Response of glyphosate-resistant and glyphosate-susceptible biotypes of annual sowthistle (Sonchus oleraceus) to increased carbon dioxide and variable soil moisture

AbstractThe growth response of annual sowthistle (Sonchus oleraceusL.) to anticipated future climate conditions is currently unknown, and thus two parallel studies were conducted dealing with glyphosate-resistant (GR) and glyphosate-susceptible (GS) biotypes ofS. oleraceus. The glyphosate efficacy study was conducted using different doses of glyphosate (0 [control], 180, 360, 720 [recommended dose], and 1,440 g ae ha−1) at two different moisture levels (well-watered and water-stressed conditions). In the second study, the growth and seed production of these biotypes were studied under different atmospheric carbon dioxide (CO2) concentrations (450 and 750 ppm) and under well-watered (100% field capacity) and water-stressed (50% field capacity) conditions. Results showed that the GR biotype survived (>68%) at 1,440 g ha−1, but for the GS biotype, no plant survived, and both biotypes were slightly (<10%) affected by moisture regimes. In the elevated CO2condition, the GS biotype plants were >38% taller and produced >44%, >18%, and >21% more leaves, buds, and seeds, respectively, compared with the ambient CO2concentration under both moisture regimes. The biomass also increased by 27% in comparison with the ambient CO2concentration. For the GR biotype, plants at the elevated CO2level, while they also grew 38% taller in comparison with the ambient CO2concentration, the numbers of leaves, buds, and seeds and biomass were not affected by this increase in CO2. Results showed that there were minimal changes in response to glyphosate for GR and GS biotypes ofS. oleraceuswith or without moisture stress. Our study suggests that future climate change with elevated CO2levels can affect the response ofS. oleraceusto glyphosate, and such knowledge will be helpful for weed management in the future.

Effects of spermidine and salinity stress on growth and biochemical response of paraquat‐susceptibe and ‐resistant goosegrass (Eleusine indica L.)

This study aimed to investigate the interaction effect of spermidine (Spd) and salinity stress on growth, photosynthetic rate, antioxidant system and free polyamines (PAs) contents of goosegrass (Eleusine indica L.) seedlings. E. indica was raised in a growth chamber under normal and toxic salt stress (100 mM of NaCl) and sprayed with 0 and 1.00 mM of Spd. The degree of growth inhibition caused by salt stress was lower in a paraquat‐resistant (R) biotype compared to a paraquat‐susceptible (S) biotype. Salt stress significantly elevated the accumulation of malondialdehyde, electrolyte leakage and proline and resulted in the degradation of chlorophyll; reduction in chlorophyll fluorescence; and a decrease in photosynthetic rate, relative water content and biomass. Spd‐treated plants maintained higher activities of antioxidant enzymes (catalase, superoxide dismutase and peroxidase), a greater rate of photosynthesis and lower osmotic pressure than untreated plants in the S biotype. Endogenous Spd content was reduced significantly in response to salt stress in both biotypes, but free PAs content in the S biotype was remarkably enhanced with exogenous Spd application under normal or salinity stress conditions. The result indicated that the S biotype was more sensitive to salinity than the R biotype; meanwhile, exogenous Spd maybe play an important role in protecting S biotype plants from salt stress.

Evidence, Mechanism and Alternative Chemical Seedbank-Level Control of Glyphosate Resistance of a Rigid Ryegrass (Lolium rigidum) Biotype from Southern Spain.

Rigid ryegrass (Lolium rigidum) is one of the most troublesome weeds in different crops in the Mediterranean region. A rigid ryegrass biotype from an olive grove in Jaén province (Andalusía, southern Spain), potentially resistant to glyphosate (RG), was tested for its resistance level through dose-response assays using a susceptible biotype (SG). To test the hypothesis of a non-target-site-based resistance, as point mutations are far less common mechanisms of glyphosate resistance, studies were also conducted to elucidate whether resistance was associated with biochemical, metabolism, molecular and/or physiological mechanisms. Alternative herbicide-based control options, including single-herbicide or herbicide mixtures with glyphosate, applied at seedling, tillering or full heading stages, were tested in field experiments for 2 years for their efficacy against rigid ryegrass plants and their effects on the soil seed bank. Resistance levels of the RG biotype were 23- (LD50) and 7-fold (GR50) higher compared to the SG biotype. The SG biotype exhibited a significantly greater shikimic acid accumulation than the RG one. At 96 HAT, 58 and 89% of applied 14C-glyphosate was up taken by leaves of RG and SG biotype plants, respectively, and, at this time, a significantly higher proportion of the glyphosate taken up by the treated leaf remained in its tissue in RG plants compared to the SG ones. The RG biotype did not reveal any point mutation in the glyphosate target site EPSP synthase. Overall, results confirmed reduced glyphosate uptake and translocation as being the mechanism involved in glyphosate resistance in the RG biotype. RG biotype responses to the alternative treatments tested in situ indicated that herbicide applications at the later growth stage tended to be less effective in terms of immediate effects on population size than earlier applications, and that only in some cases, the removal of at least 85% of the RG biotype was achieved. However, with few exceptions, the alternative treatments tested appeared to be highly effective in reducing the seed bank irrespective of the growth stage. The frequency of the resistant phenotype in the progeny of surviving plants of the RG biotype was dependent on treatment. Results suggest that a potential exists for effective management of glyphosate-resistant rigid ryegrass in olive groves in southern Spain.

Glyphosate no controle de biótipos de azevém e impacto na microbiota do solo

Avaliou-se neste trabalho a resistência de azevém (L. multiflorum) ao glyphosate e o impacto do controle desses biótipos sobre a respiração e biomassa microbiana do solo. Foram conduzidos dois ensaios: no primeiro foram avaliadas a intoxicação e a massa seca das plantas de biótipos de três populações de azevém: população 1 (reconhecidamente resistente), população 2 (resistência intermediária), e população 3 (sensível ao glyphosate), submetidas a diferentes doses de glyphosate (200, 400, 800, 1.600 e 3.200 g ha-1). No segundo ensaio foram avaliados a massa seca da parte aérea, a altura de plantas, o número de folhas de azevém e a respiração e massa microbiana do solo cultivado com os biótipos resistente e sensível, com e sem aplicação de glyphosate (480 g ha-1). Aos 14 DAT, observou-se morte do biótipo sensível quando tratado com doses a partir de 200 g ha-1 de glyphosate. Nos biótipos resistentes e com nível intermediário de resistência, a toxicidade do glyphosate às plantas de azevém foi de 85% na maior dose avaliada. O biótipo resistente apresentou maior produção de massa seca da parte aérea aos 42 DAT e na rebrota, aos 72 DAT, quando comparado ao biótipo intermediário. O biótipo sensível apresentou maior altura de plantas, número de folhas e massa seca da parte aérea, em comparação ao resistente, quando não tratados com o glyphosate. Não foi observada diferença na atividade microbiana do solo entre os tratamentos avaliados.

Triazine Resistance in a Biotype of Wild Radish (Raphanus raphanistrum) in Australia1

This study documents the first case of triazine resistance in wild radish and the resistance mechanism involved. The high survival (57 to 97%) of the resistant (R) biotype progeny plants treated at a rate four times higher than the commonly recommended rate of simazine or atrazine clearly established that the R biotype plants were resistant to triazines. All the plants of the susceptible (S) biotype plants were killed when treated at half the commonly recommended rate of atrazine (0.5 kg/ha) or simazine (0.25 kg/ha). The dry weight of the S biotype was reduced by 89 to 96% at the commonly recommended rate of atrazine or simazine, while the dry weight of the R biotype plants was reduced by only 36 to 54% even when treated at a rate four times higher than the commonly recommended rate of atrazine or simazine. The growth-reduction–ratio values indicated that the R biotype progeny plants were 105 and 159 times more resistant to atrazine and simazine, respectively, than the S biotype plants. Leaf chlorophyll fluorescence yield was reduced by 97% in the S biotype 24 h after application of triazine compared with only 9% reduction in the R biotype, indicating that the resistance mechanism involved is target-site based. The R biotype was effectively controlled by herbicides of different modes of action.Nomenclature: Atrazine; simazine; triazine; wild radish, Raphanus raphanistrum L. #3 RAPRA.Additional index words: Dry weight, leaf chlorophyll fluorescence.Abbreviations: ALS, acetolactate synthase; DAE, days after emergence; GR50 ratio, the ratio of the herbicide rate required to inhibit the growth of resistant biotype progeny plants by 50% to the rate required to inhibit the growth of S biotype plants by 50%; PS II, photosystem II; R, resistant (biotype); S, susceptible (biotype); SE, standard error; TT, triazine tolerant; WA, Western Australia.

Propanil activity, uptake and metabolism in resistant Echinochloa spp. biotypes

Field resistance of Echinochloa spp. to propanil has been previously reported in Costa Rica, Colombia and Arkansas (USA). In this study, the mechanism of resistance was investigated in three resistant (R) and three susceptible (S) biotypes. The shoot fresh weight reduction in pot‐grown plants from a post‐emergence spray of propanil at 2.44 kg a.i. ha−1 on biotypes R/S from Costa Rica, Colombia and Arkansas was 35/98%, 25/79% and 20/82% respectively. In vitro chlorophyll fluorescence data from leaf tissue incubated in propanil showed that photosynthesis was inhibited in all biotypes, indicating that the propanil‐binding site and enzyme were not altered. After transfer to herbicide‐free solution, photosynthesis recovered only in resistant biotypes, indicating that the mechanism of resistance was caused by enhanced metabolism of the herbicide. Simultaneous treatment with fenitrothion, an aryl acylamidase inhibitor, prevented the recovery of photosynthesis in leaf tissue in two resistant biotypes. In contrast, the cytochrome P450 mono‐oxygenase inhibitor, 1‐aminobenzotriazole, did not prevent recovery from propanil in leaf tissue. Application of 14C‐propanil to the second leaf of intact Echinochloa plants showed that c. 90% of the radioactivity remained in the treated leaf for up to 72 h after application. No major differences in translocation between R and S biotype plants were found. TLC analysis of tissue extracts from the treated leaves showed substantially less radioactivity associated with propanil, present after 72 h in rice or in the three R biotypes, compared with S biotypes.

Interference and Water Use of Biotypes Differing in Sensitivity to MSMA

Biotypes of common cocklebur were identified, which were assumed to differ only with respect to sensitivity to MSMA. Water use of these biotypes when grown as isolated plants in a growth chamber was determined with stem flow gauges. The MSMA-tolerant biotype exhibited less whole-plant sap flow at media moisture levels above 17%. Furthermore, only in the tolerant biotype did sap flow differ between the upper and lower canopy; the upper canopy had greater sap flow. Field experiments were conducted to compare growth parameters, water use and competitive ability toward cotton of the MSMA-sensitive and -tolerant biotypes. Sensitive biotype plants were taller and had greater leaf area than those of the tolerant biotype; dry weight was equivalent. The tolerant biotype used less water and reduced seed cotton yield more than the sensitive biotype.

Resistance of Amaranthus hybridus to atrazine

SummaryResistance of weeds to triazine herbicides has been recorded in many countries. The extent of the problem in South Africa is uncertain. In a pilot study, the atrazine resistance of Amaranthus hybridus L. (smooth pigweed) was investigated. Suspected resistant (R) and susceptible (S) biotypes were treated with commercially formulated atrazine. After post‐and pre‐emergence applications under tunnel conditions, it was found that the suspected R biotype plants were not affected at herbicide dosages of belween 1.25 and 25.0 kg a.i. ha‐1, i.e. up to 20 times gieater than the lowest recommended dosage. However, the S biotype plants were killed by the lowest dosage. In the fieid, mortalities in the R biolype were not observed after post‐emergence applications of 1.25‐10.00 kg a.i. ha‐1. In contrast, all S biotype plants were killed. In tunnel experiments, the R biotype was also found to be resistant to cyanazine and cyanazine+atrazine, while slight tolerance to linuron was observed. All these treatments resulted in 100% mortality of the S biotype. Although S biotype seeds oi A. hybridus were found to germinate slightly sooner under controlled conditions than R biotype seeds, preliminary results suggest that there are no major differences. Indications are that, although the growth of the S biotype may be greater than that of the R biotype, the competitive effect of the two biotypes on crop seedlings may well be similar.

Response of a Chlorsulfuron-Resistant Biotype ofKochia scopariato ALS Inhibiting Herbicides and Piperonyl Butoxide

Greenhouse and laboratory studies were conducted to determine kochia resistance to a spectrum of acetolactate synthase (E.C.4.13.18) (ALS)-inhibiting herbicides. The chlorsulfuron-resistant biotype plants were resistant to six herbicides: triflusulfuron, thifensulfuron, halosulfuron, imazamethabenz, chlorsulfuron, and nicosulfuron. But, the resistant biotypes showed sensitivity similar to the susceptible biotypes to three herbicides: metsulfuron, imazethapyr, and imazaquin. The resistant biotypes were slightly less sensitive to primisulfuron, chlorimuron, and flumetsulam than the sensitive biotypes. The I50values for 50% inhibition of the ALS enzyme indicated that the resistant biotype was 22, 18, and 16 times more resistant to primisulfuron, chlorsulfuron, and thifensulfuron than the susceptible biotype. In contrast, the I50ratios (resistant/susceptible) were 3, 2, and 1 for flumetsulam, nicosulfuron, and imazethapyr, respectively. The altered ALS enzyme system of the resistant biotype showed a differential response for the ALS-inhibiting herbicides. Addition of a mixed function oxidase inhibitor, piperonyl butoxide (PBO) at 2 kg ha−1, to primisulfuron and thifensulfuron increased visual injury and reduced plant height of the chlorsulfuron-sensitive kochia biotype plants. The addition of PBO to primisulfuron enhanced visual injury of the resistant biotype at low rates of primisulfuron.

Seed Biology of Sulfonylurea-Resistant and -Susceptible Biotypes of Prickly Lettuce (Lactuca serriola)

The persistence of herbicide-resistant biotypes within a given weed population can be highly correlated with the longevity of its seed in the soil and its reproductive ability. This study compared seed longevity of sulfonylurea-susceptible (S) and -resistant (R) biotypes of prickly lettuce in soil at three depths and two locations. Seed longevity in soil was not different between R and S biotypes. Seed longevity was longer when seed were buried compared to seed placed on the soil surface. A field study on seed production showed that prickly lettuce plants produced an average of 14 flower heads and 181 seed per day. Average seed weight was 0.6 mg. No differences were observed in the fecundity or seed viability between the R and S biotypes. However, seed from R biotype plants germinated as fast or faster than seed from S biotype plants.