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1.
Screening for Drought Tolerance: Soybean Germination and its Relationship to Seedling Responses 总被引：3，自引：0，他引：3
Seventeen determinate soybean ( Glycine max L.) cultivars from maturity groups V through VIII were screened for drought tolerance during germination and seedling stages. Germinating seeds and hydroponically-grown seedlings were subjected to osmotic stresses of -0.3 and -0.5 MPa using polyethylene glycol M.W. 8000. Genotypic variability was found among the cultivars for all the parameters analyzed in both germination and seedling tests. Germination stress index was lower for seeds exposed to -0.5 MPa than for -0.3 MPa osmotic stress. Lower osmotic potential in the treatment medium was also correlated with lower leaf water potential in seedlings subjected to it. A significant relationship was found between fresh weight and height stress indices. The cultivars that grew taller under drought stress conditions had greater dry matter accumulation and higher germination stress indices indicating the reliability of height to predict cultivar performance under such conditions. The cultivars Lee-74 and Wright had higher dry matter accumulation, greater height, and better germination under stress conditions than the other cultivars tested. Conversely, the cultivars Ra 401 and Bay performed poorly in the drought tests at both levels. In the seedling tests, there was no strong relationship between the leaf water potential and the overall performance of the plant suggesting no clear osmoregulatory mechanism. Based on results from germination and seedling tests, the cultivars Lee-74, Wright , and Ra 401 were selected for further studies in greenhouse and field trials. 相似文献
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S. Grzesiak W. Filek G. Skrudlik B. Niziol 《Journal of Agronomy and Crop Science》1996,177(4):245-252
Experiments were performed to evaluate seed germination and seedling growth in simulated drought as screening techniques for drought tolerance raring. Several laboratory screening tests were evaluated for ability to estimate drought resistance in 18 cultivars of legume plants (field bean, soybean, field pea, lupine). Drought was simulated by a water solution of mannitol of chemical water potential ψ= -0.3 and -0.6 MPa. Both solutions significantly affected seed germination (final germination and promptness index) and seedling growth parameters (seedling height, dry matter of shoot and root as well as leaf injury by drought and high temperature). The tested cultivars could be grouped as drought resistant and drought susceptible plants. Drought tolerance ratings of legume plants in the laboratory tests were, on the whole, consistent with the ratings based on estimation of direct effects of soil drought on seed yield in field experiments. Measurements of electroconductivity of leaf diffusate to evaluate invisible injury caused by drought or high temperature were found to be an adequate criterion for drought tolerance rating. It is concluded that tolerance to drought stress in growing seedlings can be screened for by using mannitol containing nutrient solution. According to the results collected in this research, varieties differences in seed germination, seedling growth and leaf injury affected by drought or heat temperature were evident, however, not all treatments appeared to be equally useful for screening of legume species cultivars. 相似文献
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V. T. Sapra E. Savage A. O. Anaele C. A. Beyl 《Journal of Agronomy and Crop Science》1991,167(1):23-28
Six wheat ( Triticurn aestivum L.) and ten triticale (x Triticosecale Wittmack) cultivars were screened for water stress tolerance during germination and seedling stages in the laboratory and growth chamber, respectively. Germinating seeds and hydroponically-grown seedlings were subjected to osmotic stresses of –0.3 and –0.6 MPa using polyethylene glycol M. W. 8000. Both species and cultivar differences were found among the tested genotypes for all the parameters analyzed in both germination and seedling tests. Germination stress index was lower for seed exposed to -0.6 MPa than for -0.3 MPa osmotic stress. A significant relationship was found among plant height, fresh weight and dry weight stress indices evaluated during the seedling test. The cultivars that grew taller under stress conditions had greater dry matter accumulation, as well as higher germination and water uptake stress indices indicating the reliability of height to predict cultivar performance under such conditions. The cultivars Stacy (wheat) and Eu 14/15 (triticale) had higher dry matter accumulation, higher water uptake and leaf water potential, greater height and better germination under stress conditions than the other cultivars tested. Conversely, the cultivars GA 781014 (wheat) and Am 4147 (triticale) performed poorly with respect to all the parameters analyzed. Based on results from germination and seedling tests, the cultivars Stacy and Eu 14/15 were selected for more stress studies in the greenhouse and field. 相似文献
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Mahmoud Abo Elsaud El-Rawy Muhammad Youssef 《Journal of Crop Science and Biotechnology》2014,17(3):183-189
Polyethylene glycol and cell membrane stability (CMS) assay were used to evaluate drought and heat tolerance, respectively, among 14 wheat lines based on seedling traits and molecular analysis. Significant variation was evidenced for all the investigated seedling traits. Different levels of heritability and genetic advance were found among the tested traits, indicating whether the trait is controlled by additive or non-additive gene action. Drought caused a significant reduction in root and shoot lengths. However, root/shoot ratio under drought stress was increased. Root length showed a highly significant negative correlation with drought susceptibility index (DSI) under drought conditions. Cluster analysis based on seedling traits separated lines mainly by DSI and CMS. Some lines showed drought and heat tolerance by exhibiting a low DSI with high CMS. Sequence-related amplified polymorphism (SRAP) generated a total of 135 bands, with a level of polymorphism ranging from 30 to 86% among the tested lines. SRAP showed its efficiency in discriminating wheat genotypes by gathering all high-DSIlines in one sub-cluster and generating 10 and 3 unique and specific bands for high-DSI-lines and low-DSI-lines, respectively. These bands could be used for further work as SRAP markers associated with drought tolerance in wheat. 相似文献
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Pooran M. Gaur Srinivasan Samineni Mahendar Thudi Shailesh Tripathi Sobhan B. Sajja Veera Jayalakshmi Durdundappa M. Mannur Adiveppa G. Vijayakumar Nadigatla V. P. R. Ganga Rao Chris Ojiewo Asnake Fikre Paul Kimurto Robert O. Kileo Nigusie Girma Sushil K. Chaturvedi Rajeev K. Varshney Girish P. Dixit 《Plant Breeding》2019,138(4):389-400
Chickpea (Cicer arietinum L.) is a dry season food legume largely grown on residual soil moisture after the rainy season. The crop often experiences moisture stress towards end of the crop season (terminal drought). The crop may also face heat stress at the reproductive stage if sowing is delayed. The breeding approaches for improving adaptation to these stresses include the development of varieties with early maturity and enhanced abiotic stress tolerance. Several varieties with improved drought tolerance have been developed by selecting for grain yield under moisture stress conditions. Similarly, selection for pod set in the crop subjected to heat stress during reproductive stage has helped in the development of heat‐tolerant varieties. A genomic region, called QTL‐hotspot, controlling several drought tolerance‐related traits has been introgressed into several popular cultivars using marker‐assisted backcrossing (MABC), and introgression lines giving significantly higher yield than the popular cultivars have been identified. Multiparent advanced generation intercross (MAGIC) approach has been found promising in enhancing genetic recombination and developing lines with enhanced tolerance to terminal drought and heat stresses. 相似文献
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PEG模拟干旱胁迫下不同大麻品种萌发期抗旱性评价 总被引：1，自引：1，他引：0
萌发期是大麻生长周期中的一个关键时期,此期的干旱对大麻生长及产量有着重要的影响。本研究选用云麻1号等10个大麻品种为实验材料,采用PEG-6000模拟干旱胁迫的方法,对大麻萌发期的抗旱性进行分析和评价。通过高渗透压下初步筛选出萌发性和抗旱性较好的5个大麻品种。在不同PEG浓度下大麻萌发期抗旱性评价中发现,低浓度PEG溶液能促进大麻种子萌发,随着PEG浓度的增加,大麻种子萌发受到的抑制作用越大,当PEG浓度为20%时,不同品种的萌发指标差异显著,可以在此浓度下,进行抗旱性大麻品种(系)的筛选鉴定。通过隶属函数法综合评价发现,云南的3个大麻品种表现出较强的抗旱性,其中云晚6号萌发期的抗旱性最强。 相似文献
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The present study aimed to assess the effect of contrasting levels of molecular and phenotypic diversity among polycross parents of orchardgrass on the performance of synthetic progeny with respect to physiological responses and drought tolerance. Four polycross groups each composed of six parental plants were evaluated under normal irrigation and drought stress conditions. A number of 923 inter simple sequence repeats and sequence related amplified polymorphism markers and several phenotypic traits were used to select contrasting levels of diversity (high and low) in parental genotypes. Highly significant correlation was observed between molecular distance and progeny performances at both normal irrigation and drought stress conditions. High molecular diversity among polycross parents led to a significant yield advantage of first generation progeny with averages of 34.40% for normal irrigation and 48.10% for drought stress conditions. Also crosses between genetically distant parents produced progeny with considerable drought tolerance and yield stability. Positive associations between phenotypic distance of parents and progeny performance were found for most physiological traits at both moisture regimes but phenotypic distances had weak association with forage yield, stress tolerance index and yield stability of progeny. Significant associations between drought tolerance index and some physiological traits confirmed the importance of these traits in conferring drought tolerance of orchardgrass. Our results underscore the effectiveness of marker‐assisted polycross breeding to improve drought tolerance and yield stability through physiological traits in orchardgrass. 相似文献
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以6个宽叶雀稗材料为研究对象,配置6个浓度的PEG-6000溶液模拟不同的干旱胁迫强度,研究供试材料的种子相对发芽势、相对发芽率、相对发芽指数和相对活力指数随干旱胁迫强度增加的变化情况,并采用隶属函数法综合评价供试材料种子萌发期的抗旱性.结果表明:1)随PEG胁迫强度增加,宽叶雀稗种子的相对发芽势、相对发芽率、相对发芽指数和相对活力指数总体呈下降趋势.2)通过线性回归方程确定宽叶雀稗材料PW 01、PW 06、PW 08、PW15、PW 17和PW 22的半致死PEG胁迫强度分别为:-1.31,-1.48,-1.18,-1.09,-0.81 MPa和-0.86 MPa.3)6个宽叶雀稗材料种子萌发期的抗旱性强弱顺序为:PW 06＞PW 01＞PW 08＞PW 15＞PW 17＞PW 22. 相似文献
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Sugar beet progeny lines screened for both high water use efficiency and high sugar yield under drought stress conditions in the field were assessed for the rate of seed germination and early seedling growth in water deficit stress, induced by mannitol solutions. Seeds of nine different sugar beet progeny lines were grown in three experimental conditions using filter paper, perlite and water agar as substrate. Three levels of 0.0, 0.2 and 0.3 m mannitol concentrations were applied in each experiment. A factorial design was used with three replications. Germination percentage was determined in all experiments. Seedling growth parameters such as cotyledon fresh weight, cotyledon dry weight, root fresh weight, root dry weight (RDW) and root length (RL) were measured experimentally. Abnormality was only recorded in the filter paper experiment. The results showed that drought stress could be simulated by mannitol solution and significant differences were found between stress levels for seedling characteristics. Distinct genetic variances were found among progeny lines with respect to germination and early seedling growth characteristics, except for cotyledons and RDW. Seedling growth and germination rates severely declined at the highest concentration of mannitol. The rate of abnormality was increased progressively at the germination stage with an increase in mannitol concentration but it was more pronounced in the drought‐susceptible progeny lines. The highest values of relative germination % and relative growth % of RL were obtained for the most tolerant line. In conclusion, seedling characteristics, in addition to other physiological components involved in the seed germination process under specific stress conditions, may be considered for breeding purposes. 相似文献
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以6份抗旱性不同的玉米自交系为试材,用不同浓度的PEG-6000(polyethylene glycol,PEG)渗透溶液进行模拟干旱胁迫处理,分析玉米萌芽期中胚轴长、胚芽鞘长及苗长的变化,并将其与田间干旱胁迫处理下相应玉米自交系产量及产量相关性状的抗旱指数进行相关分析,以期揭示萌芽期玉米幼苗相关性状与其抗旱性的关系。结果表明:(1)萌芽期随着PEG浓度增加,玉米自交系胚芽鞘长、中胚轴长及苗长都呈下降趋势,其中苗长降低幅度最大,平均降幅为14%,中胚轴长次之,平均降幅为11%;(2)方差分析表明,不同玉米自交系幼苗的中胚轴长、胚芽鞘长在自交系间及PEG浓度间差异极显著,苗长在PEG浓度间差异极显著;(3)花期田间干旱胁迫下,各玉米自交系的千粒重、穗粒数及产量较正常灌溉明显下降,且其平均降幅分别为8%、14%、13%;(4)通过玉米田间产量及产量相关性状抗旱指数与萌芽期各性状相关性分析表明,中胚轴长与千粒重、穗粒数及产量的抗旱指数呈显著或极显著正相关。胚芽鞘长与千粒重、穗粒数及产量的抗旱指数呈极显著正相关,而在5%的PEG-6000渗透溶液模拟干旱胁迫下,胚芽鞘长与千粒重抗旱指数相关系数最高为0.832。因此,胚芽鞘较长的自交系其抗旱性较强,胚芽鞘长度可作为玉米早期抗旱性筛选的重要指标。 相似文献
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Assessing morphological characteristics of elite cotton lines from different breeding programmes for low temperature and drought tolerance 
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下载免费PDF全文 B. Singh E. Norvell C. Wijewardana T. Wallace D. Chastain K. R. Reddy 《Journal of Agronomy and Crop Science》2018,204(5):467-476
Cotton breeders in the United States strive to develop region‐specific genotypes adapted to low temperatures and variable soil moistures during early‐season planting. Nine elite upland cotton germplasm (Gossypium hirsutum L.) lines, representing public breeding programmes from nine states across the cotton belt, were evaluated for cold and drought stresses during seed germination and seedling growth stages. Lines were subjected to three treatments, such as low temperature well‐watered (22/14°C, WW), optimal temperature drought stress (30/22°C, DS) and optimal temperature well‐watered (30/22°C, WW; control), to examine genotypic variability for cold and drought tolerance. The treatment including drought stress was irrigated at 50% of the control. Shoot and root traits measured at 25 days after planting were significantly affected by drought and low temperature, where significant genetic variability among lines was observed for both shoot and root parameters. Response indices were developed to quantify variation in the degree of tolerance among the lines to low temperature and drought. Accordingly, OA‐33 was identified as the most low‐temperature‐tolerant line and Acala 1517‐99 as the most drought‐tolerant line. Identification of both cold‐ and drought‐tolerant genotypes suggests existing genotypic variability could provide breeders the opportunity to improve cultivar response to early‐season drought or cold conditions. 相似文献
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Absence of a genetic relationship between salt tolerance during seed germination and vegetative growth in tomato 总被引：10，自引：0，他引：10
Two approaches were used to determine the relationship between salt tolerance during seed germination and vegetative growth in tomato. First, F4 progeny families of a cross between a breeding line, ‘UCT5’ (salt sensitive at all developmental stages), and a primitive cultivar, ‘PI 174263’ (salt tolerant during germination and vegetative growth), were evaluated in separate experiments for salt tolerance during germination and vegetative growth. There were significant differences among the F4 families in both the rate of seed germination and the plant growth (dry matter production) under salt stress. There was, however, no significant correlation between the ability of seeds to germinate rapidly and the ability of plants to grow under salt stress. In the second approach, selection was made for rapid germination under salt stress in an F2 population of the same cross and the selected progeny was evaluated for salt tolerance during both germination and vegetative growth. The results indicated that selection for salt tolerance during germination significantly improved germination performance under salt stress; a realized heritability estimate of 0.73 was obtained. Selection for salt tolerance during germination, however, did not affect plant salt tolerance during vegetative growth; there was no significant difference between the selected and unselected progeny based on either absolute or relative growth under salt stress. Obviously, in these genetic materials, salt tolerance during germination and vegetative growth are controlled by different mechanisms. Thus, to develop tomato cultivars with improved salt tolerance, selection protocols that include all critical developmental stages would be desirable. 相似文献
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Drought tolerance is one of the most important objectives of sugar beet breeding programs in semi-arid regions, particularly
during the last decade. Due to global climate changes and limitations of agricultural irrigation water, varieties with drought
tolerance are taken into consideration in order to avoid yield losses due to drought. In this study, drought tolerance of
76 S1 lines (full-sib families) that had been extracted from a genetically broad base multigerm sugar beet open pollinated population,
were examined. Test crosses were made between the lines as pollinators and a cytoplasmic male sterile (CMS) single cross.
The consequent hybrids along with checks were evaluated during 2007 and 23 more tolerant hybrids during 2008, in two adjacent
experiments under drought stress and non-stress conditions. Drought tolerance indices calculated based on sugar yield, such
as mean productivity (MP), geometric mean productivity (GMP) and stress tolerance index (STI) were used to assess hybrids
responses to drought. The results showed significant genetic differences for root yield and sugar yield under both conditions.
Drought tolerance indices displayed significant genetic variability for sugar yield among the hybrids. Many hybrids were drought
tolerant as compared with the original base population as indicated by their high STI. The estimates of heritability for sugar
yield in stress and non-stress conditions were much close to each other (0.31 and 0.34, respectively). Whereas, for root yield
the heritability estimate in stress condition (0.46) was relatively higher than that in non-stress condition (0.34). Significant
differences were observed among the selected hybrids for root yield and sugar yield, indicating genotypic variability for
pollinator lines derived from the population. There were no significant differences for sugar content. For increasing the
drought tolerance potential in a breeding population and developing drought-tolerant varieties by male parent, the drought-tolerant
lines could be used. 相似文献
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攀西地区玉米地方品种萌芽期抗旱性研究 总被引：2，自引：1，他引：1
为进一步利用攀西地区玉米地方品种进行抗旱育种提供理论依据,采用聚乙二醇-6000模拟水分胁迫,通过种子发芽试验,以萌芽抗旱指数、活力抗旱指数、相对发芽率、贮藏物质相对转运率和百粒重为鉴定指标,对66份攀西地区玉米地方品种萌芽期抗旱性进行鉴定。结果表明,玉米种子萌芽期抗旱指标应以萌芽抗旱指数为主,但还要以其他指标为辅,才能全面评价品种的抗旱性。66份地方品种对水分胁迫的反应有显著差异,其中18份材料表现较强的抗旱性,5份资源在多个指标上都表现极强的抗旱性。 相似文献
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通过对花粉管通道法获得的T7转MvNHX1基因的10个棉花株系和转MvP5CS基因的3个棉花株系与对照非转基因棉花D5在温室内盐和干旱胁迫下的发芽率、生理生化指标以及田间花期干旱胁迫下农艺性状和纤维品质进行分析发现:温室内盐和干旱胁迫后,转基因棉花叶片叶绿素含量、脯氨酸含量均高于对照,而丙二醛含量低于对照;田间花期干旱胁迫下,2种转基因植株果枝数、有效果枝数、铃数、有效铃数、铃重、子棉、皮棉、衣分、子指和衣指均高于对照,说明转MvNHX1基因和转MvP5CS基因植株在干旱逆境下的产量高于非转基因;经花期干旱胁迫后,2种转基因棉花的纤维断裂伸长率、短纤维率、马克隆值和纺纱一致性指数优于非转基因棉花D5。综合分析表明:2种转基因棉花的耐盐抗旱性均有提高,其中转MvNHX1基因棉花的耐盐性优于转MvP5CS基因棉花植株,而转MvP5CS基因棉花植株的抗旱性优于转MvNHX1基因棉花植株。 相似文献
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为了探索红花耐旱机制及为选育耐旱品种提供理论依据,本文研究了干旱胁迫对红花种质萌发及生长状况的影响。采用聚乙二醇(PEG-6000)模拟干旱胁迫处理,对干旱胁迫下10个红花种质萌发率及幼苗生长指标进行测量,并对各测量指标进行模糊隶属函数分析。结果表明低浓度的PEG对红花种子萌发有一定程度的促进作用；当浓度为15%时,对各指标的抑制作用明显,因此本研究选用15%的PEG浓度鉴定红花种质的抗旱性。在干旱胁迫下红花发芽势、发芽率、下胚轴重、子叶重等降低,胚芽生长受到抑制,干旱对不同种质的根长和根重的影响不一致。通过种子萌发抗旱指数及隶属函数值对红花种质萌发期抗旱性进行综合评价,其中BXY1465为萌发期抗旱性强的材料,BXY512、BXY426、BXY1466以及BXY1859属于萌发期抗旱性中等的材料,BXY1805、BXY2527、BXY2110、BXY750以及WH0086属于萌发期抗性弱的材料。 相似文献
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我国水稻常用保持系穗期耐旱性测评及育性分析 总被引：4，自引：2，他引：2
以负压式土壤湿度计和取土烘干法双重监控盆栽试验的土壤水势变化,观测我国15个常用水稻保持系的穗期耐旱性和育性特征。结果表明,K22-B、金23-B及II-32-B等保持系为穗期干旱胁迫钝感材料,而珍汕97-B、中9-B及协青早-B等为穗期干旱胁迫敏感材料;参试保持系在开花期(花粉粒充实期到小穗灌浆初期)比孕穗期(花粉母细胞分裂期到花粉粒充实期,15 d)对干旱胁迫更敏感;保持系孕穗期干旱胁迫主要伤害颖花育性,其胁迫指数与空壳率正相关(r = 0.6988**), 开花期干旱胁迫不仅伤害颖花育性并影响小穗充实,其胁迫指数与空壳率正相关(r = 0.7660**),也与秕谷率正相关(r = 0.5230);穗期耐旱性与其正常生育条件下的穗部结实性状不具直接相关性。 相似文献