不同大豆材料的抗旱性鉴定及耐旱品种筛选

发掘、创新、筛选综合性状优良、具有抗旱潜力的大豆种质对于优良大豆品种的选育及满足市场的需求具有重要意义。以山西耐旱大豆品种晋豆21为对照,10份其他地区较耐旱优异大豆品种为试验材料,通过分析自然干旱胁迫和正常灌水条件下植株叶片的3个生理生化指标（叶绿素含量、超氧化物歧化酶活性、过氧化物酶活性）的变化,及评价成熟期植株产量相关农艺性状表现,从而筛选出适宜晋北干旱地区种植的优异抗旱大豆品种。与正常灌水处理（对照）相比,自然干旱胁迫下大豆的正常生长发育受到严重影响。自然干旱胁迫处理比正常灌水处理叶绿素损失率为9.70%~44.93%,超氧化物歧化酶活性增长率0.98%~68.10%,过氧化物酶活性增长率1.66%~58.72%。与耐旱品种晋豆21相比,绥农4、绥农14、合丰56这3份材料抗旱性较强。     

不同抗旱性甘薯品种叶片生理性状差异及抗旱指标筛选

在人工控水条件下,以15个甘薯品种为试验材料,设置正常灌水和干旱胁迫2个土壤水分处理,研究了干旱胁迫条件下不同甘薯品种叶片生理特性的差异。结果表明,干旱胁迫条件下,叶面积系数均不同程度下降,反映了品种抗旱性的差异。通过抗旱系数聚类分析,将15个甘薯品种分为3个抗旱类型,抗旱品种:济薯21、济薯25、济徐23、济薯15、烟薯25;中等抗旱品种:徐薯18、济薯26、北京553、济紫薯2号、济薯18;不抗旱品种:郑薯20、济紫薯3号、济薯22、济紫薯1号、凌紫。叶面积系数与抗旱系数的相关性分析表明,干旱胁迫条件下抗旱性强的甘薯品种可维持较高的叶面积系数;而正常灌水条件下的叶面积系数不能反映甘薯品种抗旱性。干旱胁迫导致功能叶叶绿素含量和相对含水量下降,叶片相对电导率升高。干旱胁迫条件下,功能叶叶绿素含量和相对含水量与甘薯品种的抗旱性呈显著正相关关系,而功能叶相对电导率则与甘薯品种抗旱性呈显著的负相关关系。因此,叶面积系数以及功能叶叶绿素含量、相对含水量和相对电导率等指标可作为甘薯品种抗旱性鉴定的评价指标。     

甘薯品种抗旱性生理指标及其综合评价初探

采用土壤干旱和室内ＰＥＧ水分胁迫测定相结合的办法，研究有关生理指标与甘薯抗旱性关系，结果表明，水分胁迫下伴随着叶片相对含水量（ＲＷＣ）的明显下降，丙二醛（ＭＤＡ）含量显著增加，质膜相对透性（ＲＰＰ）急剧上升，而过氧化氢酶ＣＡＴ活性迅速下降；抗旱性强的品种叶片ＲＰＰ和ＭＤＡ的增加幅度显著你芋不抗旱品种，而前者叶片ＲＷＣ和ＣＡＴ活性的下速度显著慢于后者，并具有比后者较强的渗透调节能力，中等抗旱品种介乎     

不同花生品种抗旱性鉴定及抗旱指标评价

本研究旨在筛选出抗旱性强的花生品种,为开展花生抗旱品种选育和抗旱基因的功能验证提供研究基础。在干旱胁迫及对照处理下,通过对13份花生品种生理指标和表型的测定和分析,筛选抗旱指标,鉴定品种抗旱性。结果表明,各指标间均存在不同程度的相关性,相关系数在0.070~0.683之间;13个花生品种的CDC值和D值整体趋势一致;主成分分析表明,总生物量、可溶性糖等6个公因子可反映花生抗旱性89.97%的原始数据信息量;聚类分析在阈值为5时,把13个品种分为4个类群（较强抗旱、中等抗旱、敏感和高感品种）,其中L147和L149具有较强抗旱能力。试验结果表明,总生物量、相对含水量、POD、可溶性糖可作为花生抗旱性快速鉴定指标。筛选出抗旱性较强的品种为L186、L147、L221和L149。     

甘薯抗旱性鉴定方法和评价指标

甘薯抗旱性鉴定方法和评价指标侯利霞(河南省农业科学院粮食作物研究所郑州450002)干旱是一种世界性灾害,全世界由于干旱引起的粮食减产比其它所有因素的总和还多。因此,干旱问题为许多农业科研工作者所关注。甘薯根系发达,可分布到土壤1.5m以下,块根含……     

辽宁省玉米品种耐旱性评价及耐旱指标鉴定

在大田和旱棚条件下,对21份辽宁省主推及新审定玉米品种耐旱性进行评价,筛选适宜辽西半干旱地区种植的玉米品种。同时,通过玉米品种的形态生理指标与减产率的相关性分析,筛选耐旱鉴定指标。结果表明:1)耐旱性极强的品种为迪卡516和辽单588,耐旱性较强的品种为辽单575、辽单586、辽单1281和东单1331,适宜于东北半干旱区推广和大面积种植; 2)株高、穗位、叶绿素含量、叶面积、根系干重、气生根层数、气生根数等7个指标与减产率呈显著负相关,可作为耐旱鉴定指标用于玉米生育期间的耐旱性综合评价; 3)干旱胁迫会增加植株根冠比,降低收获指数,影响品种的干物质分配。     

水稻品种苗期抗旱性筛选与评价

为了比较黑龙江省主栽粳稻品种苗期抗旱性,通过苗期反复干旱胁迫法,研究了干旱胁迫对水稻苗期各形态性状及反复干旱存活率等指标的影响,并通过聚类分析筛选抗旱性强的品种。结果表明,干旱处理后的株高、叶干重、叶鲜重、根数、根长、根干重等形态指标相对值均小于100%,幼苗存活率明显下降,不同品种下降幅度不同。通过对主成分分析和相关分析,得出株高、叶干重、根长及根干重可以作为水稻苗期抗旱性鉴定的形态指标。经反复干旱存活率和聚类分析,筛选出‘东农426’、‘松粳6’、‘五优一’、‘松05-274’和‘松05-276’5份苗期抗旱性较好的品种。     

不同色彩棉花抗旱性鉴定指标及评价

以抗旱性不同的白棉、棕棉和绿棉品种(品系)为试验材料,应用多元统计分析的理论与方法,研究了不同水分亏缺灌溉条件下花铃期棉花生理生化指标与抗旱性的关系.结果表明:棕色棉BC05-07-18-2抗旱性最强,绿色棉G3-6抗旱性最弱,叶片相对含水量和类胡萝卜素含量可作为棉花抗旱鉴定的重要指标,叶绿素含量和可溶性糖含量可作为参考指标.棉花品种的抗旱系数与叶片相对含水量和可溶性蛋白含量存在线性回归关系,与细胞膜透性呈显著负相关.     

天津市鲜食甘薯品种筛选试验及综合评价

为筛选出适宜天津市种植的优质、高产甘薯品种,解决天津市甘薯品种单一问题,引进6个鲜食甘薯品种进行比较筛选试验,从植株形态特征、薯块性状、外观、食味、产量等方面进行调查分析。结果表明,烟薯24号、烟紫薯3号鲜薯产量分别居第1位和第2位;徐紫薯8号、烟薯24号和烟薯26号食味较好;徐紫薯8号、烟紫薯3号为紫薯中产量较高的品种。综合分析结果表明,烟薯26号和徐紫薯8号丰产性较好、商品薯率较高,外观品质也较好,适合在天津市进行大面积种植;其余品种不适于天津市种植。     

甘薯IbCAF1基因的克隆及耐盐性、抗旱性鉴定

CAF1 (CCR4-associated factor 1) gene plays an important role in plant development and disease resistance. In this study, the IbCAF1 gene of sweetpotato was cloned according to the EST sequence. The ORF of IbCAF1 was 846 bp, encoding 281 amino acids, with a molecular weight of 32.13 kD and an isoelectric point of 4.83. The results of amino acid sequence alignment and phylogenetic tree analysis showed that IbCAF1 had higher homology with ItlCAF1, a homologous protein of Ipomoea triloba (2x), and the homology was 96.8%. IbCAF1 gene was induced and expressed by NaCl, PEG, ABA, and H₂O₂. The IbCAF1 gene was transferred into tobacco by Agrobacterium tumefaciens mediated transformation. The overexpression of IbCAF1 gene significantly improved the salt and drought tolerance of transgenic tobacco plants. After 200 mmol L ^-1NaCl and 10% PEG-6000 treatments, the transgenic tobacco plants showed significant upregulation of the genes involved in ROS scavenging system and proline biosynthesis related genes, significant increase of SOD activity, POD activity and proline content and significant decrease of H₂O₂ and malondialdehyde contents. These results demonstrate that the IbCAF1 gene could improve salt and drought tolerance in transgenic tobacco. This study will lay a foundation on salt and drought tolerance gene engineering of IbCAF1 gene in sweetpotato for the following research.     

甘薯苗期耐盐性鉴定及其指标筛选

以18个甘薯品种(系)为试验材料, 设置对照和200 mmol L ^-1 NaCl浓度处理, 通过苗期盐土栽培胁迫方式, 对各处理下各品种(系)的茎叶鲜重、根系鲜重、茎叶干重、根系干重、叶片相对电导率、F_v/F_m、SPAD值、SOD酶活性、MDA含量、脯氨酸含量、根系活力、根系Na ⁺和K ⁺含量、Na ⁺/K ⁺比值等14个生理指标进行测定, 通过对各单项指标的耐盐系数进行相关分析、主成分分析、聚类分析和逐步回归等方法对品种(系)耐盐性进行综合评价。通过主成分分析, 将盐胁迫处理下甘薯苗期的14个单项指标转换成5个彼此独立的综合指标; 通过隶属函数分析, 得到不同品种(系)苗期耐盐性综合评价值(D值), 并通过聚类分析, 将18个甘薯品种(系)划分为4种耐盐类型, 其中盐敏感型4个、弱耐盐型3个、中度耐盐型7个和高度耐盐型4个。在此基础上, 利用逐步回归方法建立了可用于甘薯苗期耐盐性评价的回归方程, 同时筛选出茎叶鲜重、根系鲜重、茎叶干重、叶片SPAD值、SOD酶活性、MDA含量、脯氨酸含量、根系Na ⁺/K ⁺比值等8个可用于甘薯苗期耐盐性评价的生理指标。本研究可为甘薯耐盐新品种选育提供种质并为甘薯苗期耐盐性评价及耐盐机制研究提供理论依据。     

A method for drought tolerance screening in sunflower

One difficulty in obtaining drought-tolerant varieties is the unequivocal evaluation of plant response to soil-water deficits. A method is proposed that allows reproducible soil-water deficit treatments to be applied to different sunflower genotypes. Maize ( Zea mays L.) plants were sown in the same pots as but earlier than some sunflower plants in order to rapidly deplete the soil water. This method was compared to a standard method in which plants under evaluation are used to dry out the soil. The method was reproducible in the evaluation of drought tolerance of four sunflower inbred lines. Advantages of the proposed method are that: (i) it allows the desired soil water content to be reached quickly; (ii) the resulting soil water content in the pot is uniform and (iii) the rate of decrease in soil water content is independent of the genotype being evaluated. Data indicate that maize plants had no effect on the growth of sunflower genotypes.     

Evaluation of grain yield and its components in wheat cultivars and landraces under near optimal and drought conditions

In a 2-years experiment, 30 wheat cultivars and 21 landraces from different countries were tested under near optimum and drought stress conditions. Plant height, number of sterile spikelets per spike, spikelets per spike, number of kernels per spike, kernel weight per spike, 1000 kernel weight and grain yield were evaluated. The number of kernels per spike, 1000 kernel weight and especially yield were more sensitive to drought stress in the cultivars than plant height and number of spikelets per spike, while in the landraces these traits did not differ under drought stress compared to near optimum conditions. The average yield of cultivars was significantly better than the average yield of landraces under near optimum as well as drought stress conditions. Path coefficient analysis showed that for cultivars under near optimum conditions there was no significant direct association of any of the analysed characters with yield, while under drought stress conditions, number of kernels per spike had a significant positive direct effect. Under drought stress conditions, the number of sterile spikelets displayed a negative direct effect, while kernel weight per spike had a positive direct effect on yield. Hierarchical cluster analysis was used as a tool to classify cultivars and landraces according to their yield ability under near optimum and drought stress conditions. Among the cultivars, two groups out of five and among one of three in the landraces were characterised by high yields in both near optimum as well as under drought stress conditions. These genotypes may serve as sources of germplasm for breeding for drought tolerance. This revised version was published online in August 2006 with corrections to the Cover Date.     

Phenotyping of productivity and resilience in sweetpotato under water stress through UAV-based multispectral and thermal imagery in Mozambique

Sweetpotato is a crucial crop to guarantee food security in sub-Saharan Africa, and drought events are considered one of the most critical factors affecting sweetpotato productivity in this region. In this study, airborne imagery based on reflectance (NDVI, CI_red-edge) and canopy temperature minus air temperature (dT) indices was used to characterize sweetpotato genotypes under drought treatments in Mozambique. Two field experiments established in rainy/hot (Trial A) and dry/cool (Trial B) seasons were assessed. In Trial A, 24 genotypes were subjected to early- (ESD), mid- (MSD) and late-season (LSD) drought stress treatments and compared against a control. In Trial B, 120 genotypes were subjected to LSD only. The percentage of reduction in vine weight (PR_VW) under drought was related primarily to temporal variation of NDVI and CI, regardless of drought treatment and seasons. dT in relation to control (dT_Amp) was associated with PR_VW in ESD-Trial A and LSD-Trial B, whereas under LSD-Trial A, dT_Amp was related to total fresh storage root weight (TRW). During the rainy/hot season, higher TRW reduction was promoted under ESD; however, under LSD, it was possible to identify productive genotypes able to withstand drought stress, highlighting their relevance for drought-tolerance selection purposes.     

农作物综合抗旱性指标的评价

阐述了作物综合抗旱性指标的研究进展、各指标应用的局限性。目前评价作物抗旱性的综合指标都仅仅是从产量方面去考察，为此，本着作物产量与品质并重的原则，提出了作物的“综合抗旱指数”（CDI），数学表达式如下：CDI ＝（DC或DI×100＋I）/2。通过对两个水稻品种不同生育时期、不同程度的控水处理，发现长穗期综合抗旱指数最小，因此，长穗期不仅是水稻产量的水分敏感期，也是品质的水分敏感期。     

Genotypic variation for drought tolerance in Vicia faba

Instability of yield in faba bean is partly caused by drought susceptibility. Four sets with 10-19 faba bean genotypes each were evaluated in multilocal field trials between 1992 and 1996. Stress occurred as natural drought in one experiment and as artificial terminal drought in three experiments. Artificial drought was induced by rain shelters; the control treatment was irrigated. Tolerance was assessed as the ratio of yield under drought (Yd) to well-watered yield (Yw). Highly significant variances between genotypes occurred; heritability of tolerance was 0.51 < h² <0.88. Exotic (North African. Latin American) genotypes were more tolerant than adapted material. Correlations between Yw and Yd were 0.77** < r <0.97**, and variance of Yd was less than one-third of the variance of Yw. Drought tolerance was negatively correlated with Yd (-0.41 < r < -0.22). Relative reduction of plant height due to drought was a promising trait to improve drought tolerance indirectly in two sets. The prospects of improving Yd are good: heritability was 0.68 < h² < 0.86. Genetic improvement of drought tolerance also seems feasible. A specific cross was proposed to create improved material.