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1.
Twenty-two genotypes of grain sorghum were grown under drought conditions by omitting one irrigation during stages of before flowering period, kernel filling period, and physiological maturity period at Assiut Univ. Farm in 1987 and 1988 seasons. The results obtained revealed that considerable variation existed among genotypes for all the studied traits. The most effective moisture stress treatment in reducing grain yield, panicle weight and plant height was during flowering stage. While 1000-kernel weight was much affected by moisture stress during grain filling period. The genotype x year interaction (σ2gy) was large compared to genotype x irrigation treatment (σ2gl) indicated that genotypes responded differently when they were grown from year to year. The genotypic variance (σ2g) for all traits were large reflecting the importance of genetic variability. Both phenotypic and genotypic correlations among traits showed that plant height and 1000-kernel weight were highly correlated with grain yield, while leaf area index was low associated with plant height.  相似文献   

2.
为探究化学调控技术对糜子叶片光合特性和产量的调控效果,以糜子品种粘丰5号和齐黍1号为试验材料,采用大田试验,设置播种前1mg/L烯效唑(S3307)和50mg/L胺鲜酯(DTA-6)浸种2个处理,以清水浸种为对照(CK),测定不同生育时期糜子的光合特性、干物质积累、农艺性状及产量构成因素等指标。结果表明,与CK相比,S3307和DTA-6浸种均可提高糜子拔节期和灌浆初期叶片叶绿素相对含量、气孔导度、蒸腾速率和净光合速率;S3307和DTA-6均可增加糜子茎粗,降低株高。S3307可提高灌浆盛期2个糜子品种茎干重、叶干重和穗干重,DTA-6对灌浆盛期糜子叶干重和穗干重有增加作用;S3307可提高2个糜子品种穗粒数;DTA-6增加了粘丰5号有效穗数,提高了齐黍1号穗粒数和千粒重。S3307和DTA-6处理下粘丰5号分别较CK增产11.05%和5.43%,齐黍1号分别较CK增产5.73%和16.24%。因此,S3307对粘丰5号、DTA-6对齐黍1号作用效果更好,增产率最高。  相似文献   

3.
Water stress after flowering, one of the major factors limiting yields of pearl millet, affects both seed setting and grain filling and is a consequence of more/less water used prior to anthesis. However, whether genotypes have different sensitivities for seed setting and filling under drought, if exposed to similar stress intensity, is unclear. Experiments were conducted in two pairs of pearl millet genotypes, that is, PRLT2/89‐33 and H77/833‐2, 863B and 841B, contrasting for terminal drought tolerance, and two genotypes, ICMR 01046 and ICMR 01029 (IL‐QTLs), introgressed with a terminal drought tolerance QTL from PRLT2/89‐33 into H77/833‐2. Total seed weight, panicle number, 100‐seed weight, seed number and stover biomass were measured at different soil moistures and throughout grain filling. Sensitive H77/833‐2 had higher seed number and yield under well‐watered (WW) conditions than in PRLT2/89‐33 and IL‐QTLs. Upon increases in water stress intensity, H77/833‐2 suffered losses mostly in stover biomass (45 %) and seed number (60 %) at 0.3 FTSW whereas the biomass and seed number of PRLT2/89‐33 decreased little (20 % and 25 %). The 100‐seed weight of H77/833‐2 decreased only 20 % under stress. Tolerant 863B also maintained a higher seed number and biomass under water stress than 841B. Grain filling duration in PRLT2/89‐33 and IL‐QTLs was similar to that of H77/833‐2 under WW conditions but lasted longer than in H77833‐2 under water stress (WS). Similarly, seed growth of 863B was longer than 841B under WS. It is concluded that the higher seed yield of tolerant parents PRLT2/89‐33 and 863B, and of IL‐QTLs under WS was explained by the retention of a higher number of seeds than in sensitive lines, while the decrease in the 100‐seed weight was proportionally less than the decrease in seed number. Phenotype with lesser number and larger size of panicles and larger grain size, like genotypes PRLT2/89‐33 and 863B, withstood post‐anthesis water stress better. IL‐QTL inherited part of these characteristics, indicating a role for the terminal drought QTL in maintaining larger seed number and higher 100‐seed weight. The continuous stover biomass increase under WW in H77/833‐2, due to tillering, might indicate that tiller growth and grains are in competition for resources after anthesis, and this may relate to the relatively shorter grain‐filling period.  相似文献   

4.
Drought tolerance in sorghum by pollen selection using osmotic stress   总被引:2,自引:0,他引:2  
A pollen selection study for drought tolerance using Poly Ethylene Glycol (PEG) as a selective agent was conducted in sorghum. Ten genotypes of sorghum suitable for post rainy season were crossed to cytoplasmic male sterile line 104A and three genotypes to 116A producing 13 hybrids. Two sets of 13 hybrids with and without pollen selection were produced. PEG at 36 per cent was applied to stigma and stylar tissue one hour before pollination for pollen selection (selective fertilization) and no treatment for control (nonselective fertilization). Hybrids thus produced through selective and non-selective fertilization were tested in moisture stress environment during post rainy season. The hybrids obtained through selective fertilization produced significantly higher mean grain yield compared to hybrids obtained through non-selective fertilization. The results indicate that selective fertilization through in vivo pollen selection using PEG as selective agent was effective in improving moisture stress tolerance of the progeny in sorghum genotypes studied. Further, the pollen selection also had influence on plant height, panicle length, panicle width, panicle weight and grain mass. Thus,the pollen selection had a significant effect on grain yield through its components and developmentally related traits. Pollen selection for osmoticstress tolerance in sorghum influences the growth and vigour of the plants resulting in superior progeny in moisture stress environment. The analysis of individual crosses indicated that pollen genotype selection was able to favour performance of the progeny. However, the pollen selection had positive effect in majority of the hybrids and the study demonstrates the transmission of the selected trait from pollen generation to progeny. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

5.
探明不同盐逆境水平对耐盐水稻穗部性状及产量构成因素的影响,旨在为沿海滩涂水稻种植和耐盐水稻高产育种提供科学依据.以'扬农稻1号'(V1)、'南粳5055'(V2)和'通海粳18-2'(V3)为试材,利用盐池设施设置O g/kg(S0)、1.5 g/kg(S1)、3 g/kg(S2)3个不同盐分水平,采用裂区试验,测定分...  相似文献   

6.
为了明确影响谷子杂交种产量的主要因子,对短穗型、中偏短穗型、中偏长穗型和长穗型4类不同谷子杂交种产量与主要农艺性状进行相关性和回归分析。结果表明,4种类型谷子杂交种的穗长与其产量差异显著。相关性分析表明,产量与出谷率之间存在显著正相关;单株穗重与单株粒重、经济系数之间存在极显著正相关,有效分蘖数与单株穗重、单株粒重和经济系数之间存在显著正相关,穗码密度与单株草重之间存在显著正相关,千粒重与穗长之间存在显著正相关。回归分析表明,谷子杂交种产量与穗粗、出谷率和千粒重呈显著正相关。  相似文献   

7.
120份谷子种质资源的农艺性状表现和遗传多样性分析   总被引:1,自引:0,他引:1  
对120份谷子种质资源的21个主要农艺性状进行遗传多样性、主成分以及聚类分析。结果表明,遗传多样性指数以主穗重和主穗粒重最高,均为2.02;变异系数以单株干草重最高,为64.12%。根据谷子种质性状间的遗传差异,对21个主要农艺性状进行主成分分析,得到10个主成分因子的累计贡献率达81.777%。通过聚类分析,将谷子种质资源分为6个类群,各类群在生育期、株高、分蘖性、籽粒产量和干草产量等性状间有明显的形态学特征,从早熟、高产和单株干草重3个方面筛选出11份优异谷子种质资源。本研究结果可为甘肃干旱高寒农业区谷子种质资源高效利用和亲本选择提供科学依据。  相似文献   

8.
A pearl millet mapping population from a cross between ICMB841 and 863B was studied for DNA polymorphism to construct a genetic linkage map, and to map genomic regions associated with grain and stover yield, and aspects of drought tolerance. To identify genomic regions associated with these traits, mapping population testcrosses of 79 F3 progenies were evaluated under post-flowering drought stress conditions over 2 years and in the background of two elite testers. A significant genotype × drought stress treatment interaction was evident in the expression of grain and stover yield in drought environments and in the background of testers over the 2 years. As a result of this, genomic regions associated with grain and stover yield and the aspects of drought tolerance were also affected: some regions were more affected by the changes in the environments (i.e. severity and duration of drought stress) while others were commonly identified across the drought stress environments and tester background used. In most instances, both harvest index and panicle harvest index co-mapped with grain yield suggesting that increased drought tolerance and yield of pearl millet that mapped to these regions was achieved by increased partitioning of dry matter from stover to the grains. Drought stress treatments, years and testers interactions on genomic regions associated with grain and stover yield of pearl millet are discussed, particularly, in reference to genetic improvement of drought tolerance of this crop using marker-assisted selection.  相似文献   

9.
The aim of this study was to evaluate oat genotypes for grain yield and yield components in both 2014-2015 and 2015-2016 growing seasons using GGE biplot analysis. Experiments were laid out according to lattice design. Biomass at harvest, grain yield, number of grain per panicle, weight of grain per panicle, flag leaf width, flag leaf height, plant height, stem diameter, thousand kernel weight, time of panicle emergence, harvest index, panicle length, and spikelet per panicle were evaluated for 56 oat genotypes. GGE biplot graphics of the first and second years explained 54.4 and 55% of total variation, respectively. Grain yield, number of grains per panicle, and weight of grain per panicle were closely and positively associated in both growing seasons. Recently registered cultivar Sari and lines 26, 29, and 30 were found as promising genotypes for Çanakkale conditions. Traits of genotype at different growing seasons can be visually studied using different genotype-by-trait (GT) biplots.  相似文献   

10.
Normalized difference vegetation index (NDVI), which is a measure of leaf greenness (chlorophyll content), is considered to be correlated with crop productivity. This study was conducted to examine genotypic variations for NDVI at different growth stages and its relationship to yield in winter wheat under terminal heat stress. Thirty winter wheat genotypes were evaluated at two locations in 2009–2010 and 2010–2011 in Uzbekistan. The NDVI was recorded at booting, heading, milk and dough stages. The wheat genotypes differed significantly for NDVI at each stage. Grain yield ranged from 3.9 to 6.1 t/ha. Wheat genotypes differed in per cent decline in NDVI from booting to dough stage. However, several high‐yielding genotypes maintained higher NDVI than low‐yielding genotypes when heat stress was evident. The findings suggest change in NDVI during heat stress could be a measure of tolerance. The positive correlation of NDVI with grain yield suggests that it could be used as an indirect selection criterion for identifying physiologically superior, high‐yielding wheat lines under terminal heat stress.  相似文献   

11.
O. P. Yadav 《Plant Breeding》2008,127(2):208-210
The crop cultivars targeted for drought prone areas need to combine drought tolerance and high yield. The present study was conducted to assess the performance of three selected pearl millet landraces, four exotic elite populations and their 12 crosses. They were evaluated for yield, yield components and a drought susceptibility index that was calculated using yield data from drought and non‐drought environments. In the non‐drought season, the exotic populations had significantly higher grain yield than landraces. However, in the severe drought season, the landraces produced significantly greater biomass, grain and stover yields than elite populations. There was a strong relation between panicle size and ability to produce panicles and delay in flowering under severe stress. The biomass and stover yield of crosses was significantly better than parental populations under both drought stress and near‐optimum conditions. The elite populations were most sensitive to drought while crosses were as drought tolerant as landraces because they combined larger panicle size of exotics and lesser delay in flowering of landraces. The results indicated that it is possible to combine drought adaptation with high yield potential through hybridization between adapted landraces and elite genetic materials.  相似文献   

12.
华北地区谷子产量与农艺性状的综合评价分析   总被引:7,自引:0,他引:7  
对华北夏谷区谷子农艺性状与产量性状进行灰色关联度分析,探讨主要农艺性状对产量的影响,为谷子优良种质资源利用及高产品种选育提供依据。以2016年全国谷子品种区域适应性联合鉴定华北夏谷区常规组参试的17个品种(系)为材料,采用相关分析和灰色关联度分析相结合的方法,对产量相关8个农艺性状进行综合评价。结果表明,供试材料9个农艺性状均存在变异,变异幅度2.69%~11.71%;穗粒重、单穗重、出谷率与产量呈显著正相关;9个农艺性状对谷子产量影响大小依次为穗粗>单穗重>穗粒重>千粒重>株高>出谷率>穗长>生育期,穗粗、单穗重和穗粒重对产量的影响最大。说明谷子产量育种应重视大穗、大粒、穗粒重高的种质资源利用,并适当关注株高。  相似文献   

13.
晚籼稻抽穗期冷害生态适应性评价   总被引:1,自引:0,他引:1  
选择生育期相近的迟熟高产杂交稻组合或水稻品种(品系),在自然条件下分期播种,寻找水稻抽穗期冷害相关的形态评价指标,并对参试材料进行抽穗期耐冷生态适应性评价。抽穗期遭受低温冷害胁迫后,主要农艺性状中受冷害程度大小顺序依次是每穗实粒数、单蔸产量、结实率、每穗总粒数、株高、穗长、千粒重;单蔸产量相对受害率(RDP)与每穗实粒数RDP、结实率RDP、剑叶叶色分、抽穗期延尺天数分成极显著正相关。在低温冷害胁迫条件下,水稻不同基因型的抽穗期耐冷能力存在明显的差异。将判别水稻抽穗期耐冷能力的形态指标--每穗实粒数RDP、结实率RDP、剑叶叶色、抽穗期延迟天数、苞穗率增加值进行量化,综合判别参试材料抽穗期对低温冷害的生态适应性。研究结果表明:籼穗交材料95LR102后期耐冷能力强;带有部分粳稻血缘、正在生产中大面积种植的杂交稻  相似文献   

14.
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   

15.
Lack of water during vegetative and/or reproductive growth stages is one of the most limiting factors for bean growth. The purpose of this study was to evaluate the effects of water stress applied during two phenological stages (flowering and pod filling) on growth, yield and yield components. Two genotypes of bean ( Phaseolus vulgaris L.) were used in this study, cv. Carioca, an indeterminate Brazilian landrace, and cv. Prince, a determinate cultivar grown in Europe. Carioca appears to be generally stress-tolerant while Prince is intolerant. Plants were grown in large plastic pots covered with a black plastic sheet to protect the soil from rain and evaporation. The water stress treatments were: control (well-watered plants), WSFS (water stress during flowering stage) and WSPFS (water stress during pod-filling stage). Water stress reduced yield and yield components at both flowering and pod-filling stages. The parameters affected were seed weight, number of seeds per plant and number of pods per plant. Number of seeds per pod and seed weight were not affected. No effects of water stress were detected on harvest index. Time to maturity was slightly prolonged, especially for WSFS. Water stress at both stages resulted in lower accumulated water loss compared to the control plants. Water stress during both phenological stages reduced other growth parameters, the number of trifoliate leaves, stem height, number of main branches and number of nodes on the main stem.  相似文献   

16.
Crop tolerance to salinity is of high importance due to the extent and the constant increase in salt-affected areas in arid and semi-arid regions. Pearl millet (Pennistum glaucum), generally considered as fairly tolerant to salinity, could be an alternative crop option for salt affected areas. To explore the genotypic variability of vegetative-stage salinity tolerance, 100 pearl millet lines from ICRISAT breeding programs were first screened in a pot culture containing Alfisol with 250 mM NaCl solution as basal application. Subsequently, 31 lines including many parents of commercial hybrids, selected from the first trial were re-tested for confirmation of the initial salinity responses. Substantial variation for salinity tolerance was found on the basis of shoot biomass ratio (shoot biomass under salinity/ non-saline control) and 22 lines with a wide range of tolerance varying from highly tolerant to sensitive entries were identified. The performance of the genotypes was largely consistent across experiments. In a separate seed germination and seedling growth study, the seed germination was found to be adversely affected (more than 70% decrease) in more than half of the genotypes with 250 mM concentration of NaCl. The root growth ratio (root growth under salinity/control) as well as shoot growth ratio was measured at 6 DAS and this did not reflect the whole plant performance at 39 DAS. In general, the whole plant salinity tolerance was associated with reduced shoot N content, increased K+ and Na+ contents. The K+/Na+ and Ca++/Na+ ratios were also positively related to the tolerance but not as closely as the Na+ content. Therefore, it is concluded that a large scope exists for improving salt tolerance in pearl millet and that shoot Na+ concentration could be considered as a potential non-destructive selection criterion for vegetative-stage screening. The usefulness of this criterion for salinity response with respect to grain and stover yield remains to be investigated.  相似文献   

17.
The effects of water stress on physiological attributes of drought‐sensitive (Kalyansona) and drought‐tolerant (C‐306) wheat cultivars were studied in a pot experiment. Water stress was imposed by withholding irrigation at boot and anthesis stages. Leaf water potential, leaf osmotic potential and leaf turgor potential (measured with pressure chamber and osmometer), as well as leaf diffusive resistance, leaf transpiration rate and leaf‐to‐air transpiration gradient (measured with a steady‐state porometer) were measured diurnally. Growth and yield parameters were recorded after harvesting of the crop. Triplicate data were analysed using a completely randomized design and correlations amongst these parameters were computed. Water stress was found to reduce diurnal leaf water potential and leaf osmotic potential in both the genotypes but leaf osmotic potential was significantly higher in the drought‐tolerant cultivar C‐306 than in the drought‐sensitive cultivar Kalyansona. Positive turgor was recorded in both the genotypes under water stress and non‐stress conditions. Water‐stressed plants showed significantly lower turgor potential than control plants. In diurnal observations, water‐stressed plants exhibited significantly higher leaf diffusive resistance in both genotypes at both stages. The diffusive resistance of C‐306 was predominantly higher than that of Kalyansona. Water stress decreased leaf transpiration rate at both stages but the reduction was higher at the anthesis stage. The leaf‐to‐air temperature gradient was much higher in C‐306 than in Kalyansona at the boot stage but at the anthesis stage genotypic variation was non‐significant. The capacity to maintain cooler foliage was lower at the anthesis stage than at the boot stage in both the cultivars. Shoot dry weight, number of grains, test weight, grain yield, biological yield and harvest index decreased to a greater extent when water stress was imposed at the anthesis stage, while imposition of water stress at the boot stage caused a greater reduction in plant height and number of tillers. Similarly, water stress caused a smaller reduction in growth, yield and yield attributes in C‐306 than in Kalyansona. In general, the correlation coefficient of grain and biological yield with water potential and its components was positive and highly significant. Similarly, turgor potential was also correlated positively and significantly with grain yield at both the stages, but with biological yield it was significant only at the anthesis stage. A negative and significant correlation was obtained for diffusive resistance and leaf‐to‐air temperature gradient with grain yield at the boot and anthesis stages. The rate of transpiration was also positively and significantly correlated to grain and biological yields at both the stages. Amongst the yield attributes, number of leaves and number of tillers were positively correlated at the anthesis stage, whereas leaf area and shoot dry weight were significantly correlated with grain and biological yields at both the stages.  相似文献   

18.
L. Zeng  M.C. Shannon  C.M. Grieve 《Euphytica》2002,127(2):235-245
The lack of an effective evaluation method for salt tolerance in the screening process is one of the reasons for limited success in conventional salt tolerance breeding. This study was designed to identify useful agronomic parameters for evaluation of salt tolerance and to evaluate genotypes by multiple agronomic parameters for salt tolerance at different growth stages. Twelve genotypes were grown in a greenhouse in sand and irrigated with nutrient solutions of control and treatments amended with NaCl and CaCl2 (5:1 molar concentration) at 4.4 and 8.2 dS m-1 electrical conductivity. Wide genotypic differences in relative salt tolerance based on seedling growth were identified. The duration of reproductive growth between panicle initiation and anthesis was either reduced or increased by salinity, but the response was not strictly correlated with relative salt tolerance in seed yield among genotypes. Wide genotypic differences in relative salt tolerance based on spikelet and tiller numbers were identified. Few genotypic differences were identified for fertility and kernel weight. Spikelet and tiller numbers contributed most of the variation to seed yield among parameters investigated. When genotypes were ranked for salt tolerance based on the means of multiple parameters, dramatic changes of salt tolerance at early and seed maturity stages were observed in two genotypes, GZ5291-7-1-2 and GZ178. IR63731-1-1-4-3-2 was identified with a favourable combination of salt tolerance at early seedling and seed maturity stages. Cluster group ranking of genotypes based on multiple agronomic characters can be applied in salt tolerance breeding to evaluate salt tolerance and may have great advantage over conventional methods. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

19.
谷子核心种质表型遗传多样性分析及综合评价   总被引:17,自引:0,他引:17  
通过遗传种质的多样性评估可以指导深入研究资源和育种中优异互补亲本的选择进而提高优异基因的交流累加和新品种培育的效率。本研究选用了来自世界各地的份谷子核心种质通过个表型性状的综合鉴定评估遗传多样性和筛选优异种质资源结果表明我国谷子资源的表型遗传多样性丰富单穗粒重、穗长、穗粗、株高、茎节数和生育期均表现了丰富的变异谷子育成品种遗传多样性相比农家品种下降明显育种的遗传增益主要体现在株高和穗长的适度减低,以及茎粗、茎节数、穗粗、单穗粒重、单穗重及生育期的适度增加系统聚类分析将谷子资源分成类第类以来源为东北欧国家的品种为主第类以北美和非洲的品种为主第类以东亚、南亚的品种为主我国种质可划分为春播型、春夏兼播型和南方型类型采用主成分分析法和逐步回归分析法综合评判表明叶鞘色、刚毛长度、粒色、米色、株高、穗长、茎粗和单穗粒重个性状可作为谷子表型鉴定的主要指标。  相似文献   

20.
Pearl millet (Pennisetum glaucum) is the most important cereal in crop-livestock production systems in arid and drier semi-arid environments valued for its grain and dry stover. The conventional approach of improving grain yield through greater partitioning of biomass to the grain and decreased stover yield is not a viable strategy for arid regions where biomass also needs to be improved. The current research tested the hypothesis whether biomass can be improved without extending the crop duration. The 232 F5 lines derived from a cross (J28 × RIB 335/18) were evaluated in their testcross form along with three commercial hybrids under arid zone conditions. Biomass, grain and stover yields, panicle number, grain size and grain number panicle−1 varied 1.8 to 2.7 fold in progeny testcrosses. Variation in duration of flowering time accounted for only 2% of variation in biomass, indicating that considerable scope existed for selection of testcrosses, and by implication, of F5 progenies with high biomass independent of crop duration. Stover yield accounted for 72% of differences in total biomass with remaining accounted for by grain yield. From among 92 and 132 testcrosses that had flowering time comparable to two early checks, most had significantly higher biomass, grain and stover yields than these early checks but none of the testcrosses had earliness on par with extra-early maturing hybrid HHB 67. Mean superiority of best 5% testcrosses over early checks was 58% for biomass, 68% for stover yield and 53% for grain yield. The results indicated that there are good prospects of improving biomass in arid zone pearl millet without significantly compromising crop duration.  相似文献   

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