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以我国北方地区上世纪50年代以来生产上有代表性的15个主栽品种为试材,对灌浆期穗位叶叶绿素含量、保护酶活性及膜脂过氧化产物的含量进行测定分析,比较其随年代推进和品种更替而发生的变化。结果表明,叶绿素a、叶绿素b及叶绿素总量呈增加趋势,这种趋势在灌浆后期越发明显;类胡萝卜素/叶绿素呈降低趋势,说明近期品种持绿性优于早期品种,利于后期光合作用;超氧化物歧化酶(SOD)活性呈增加趋势,膜脂过氧化产物(MDA)含量逐渐降低,这种趋势在灌浆后期尤为突出,表明近期品种具有较强的清除活性氧的能力。 相似文献
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玉米幼苗叶表面蜡质含量及成分对干旱胁迫的响应 总被引:1,自引:1,他引:0
选用抗旱性不同的两个玉米自交系Mo17和B73为试验材料,采用盆栽控水试验,设置干旱和正常浇水两个处理,研究干旱胁迫对两个玉米品种3叶期幼苗叶面蜡质含量及成分变化的影响。结果表明,在干旱处理条件下,Mo17和B73的叶片失水率和叶绿素的抽提率均低于正常条件;两个品种叶面的蜡质含量均明显高于正常条件下的蜡质含量,且Mo17在正常和干旱条件下蜡质含量均高于B73。此外,在干旱条件下,蜡质合成相关的基因KCS、CER1、CER2、GL1、GL2和GL15的表达也明显增高。玉米叶片表面蜡质合成是应答干旱胁迫的一种重要方式,抗旱品种Mo17的抗旱性比B73要强,其表面蜡质合成较强是其中一个重要原因。 相似文献
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干旱和灌溉条件下两个甘蔗品种的几个抗旱生理指标研究 总被引:3,自引:3,他引:3
分别测定了新台糖20号和桂糖11号两个甘蔗品种干旱和灌溉条件下的几个生理指标。结果表明:干旱处理引起两个甘蔗品种叶片质膜相对透性明显提高,相对含水量均明显下降,自然饱和亏缺加剧,过氧化氢酶活性和叶绿素含量下降。前4个指标以新台糖20号比较敏感,而叶绿素含量的变化以桂糖11号比较敏感。在本试验条件下,干旱处理提高了甘蔗蔗糖分和蔗汁重力纯度而降低了蔗汁还原糖分,因而提高了甘蔗品质。总的看来,似乎桂糖11号的抗旱能力比新台糖20号强,但后者的甘蔗品质较好。 相似文献
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密度调控对半干旱区不同株型玉米品种冠层和产量指标的影响 总被引:3,自引:1,他引:2
以平展型玉米品种和紧凑型玉米品种为材料,2012~2013年在吉林省西部半干旱区研究密度调控对不同类型玉米品种干旱胁迫条件下冠层和产量指标的影响。结果表明,在两年玉米灌浆期均出现中度干旱条件下,不同类型玉米品种种植密度和叶面积指数、消光系数均呈显著直线回归关系,密度和群体生长速度、果穗生长速度和产量呈先上升后下降的单峰曲线关系。通过回归方程计算,平展型和紧凑型品种最佳种植密度分别为5.4万株/hm~2和6.3万株/hm~2。相对于平展型品种,紧凑型品种平均群体生长速度和穗生长速度可以在更高种植密度条件下达到峰值。紧凑型品种在协调个体与群体适应性方面强于平展型品种,更容易适应干旱环境。 相似文献
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土壤干旱胁迫对白芥光合器官发育及光合速率的影响 总被引:5,自引:1,他引:5
唐道城 《中国油料作物学报》2000,22(1):49-52
利用旱棚盆栽研究了在土壤干旱胁迫下白芥抗旱和不抗旱品系的单叶面积,单株叶面积、出叶速度、叶绿素含量和和净光合速率。结果表明,在土壤干旱胁迫下不同白品系在不同生育时期的单叶面积、单株叶面积、出叶速度及净光合速率都下降,在一定土壤水分范围内,叶绿素含量随土壤水分的下降而增加,抗旱性强的品系受土壤干旱胁迫的影响较小。 相似文献
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陕西省不同年代旱地冬小麦光合与产量特征变化及其相互关系研究 总被引:2,自引:0,他引:2
为明确陕西省不同年代旱地冬小麦品种光合特征变化规律及其对产量的影响,选择曾在该省推广种植的20世纪40年代至21世纪初8个不同年代旱地冬小麦品种(蚂蚱麦,1940s;碧蚂1号,1950s;丰产3号,1960s;泰山1号,1970s;小偃6号,1980s;陕229,1990s;长武134,2000s;长旱58,2010s)为材料,设置正常供水和干旱胁迫两个水分处理,进行盆栽种植试验,对小麦不同生育期光合特征进行测定,并在收获期考种测产。结果表明,无论是干旱胁迫还是正常供水处理下,现代小麦品种(长武134和长旱158)花前旗叶净光合速率和单株叶面积都表现出显著优势,并与千粒重和产量呈显著正相关;但品种间花后光合特征差异减小,这对于现代小麦产量的提升可能产生了一定的限制作用;不同生育时期和不同水分处理下,旗叶蒸腾速率与种植年代之间相关性并不一致;干旱胁迫条件下,孕穗期和花后3d的旗叶水分利用效率都随品种更替呈明显上升的趋势;现代小麦品种在干旱处理下旗叶净光合速率等光合特征、千粒重等产量因素的优势受到影响,最终导致其产量增幅下降。未来应进一步提升现代小麦的光合优势,尤其是花前叶片净光合速率及叶面积的优势,并进一步提高千粒重,这将会是陕西省小麦节水高产和抗旱稳产的重要手段。 相似文献
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Improvements in dry matter digestibility of crop residues contribute to greater productivity of livestock consuming dual-purpose sorghums (Sorghum bicolor L. Moench). Delayed leaf senescence (stay-green), brown-midrib (bmr), leaf disease resistance, and high yield are among sorghum phenotypic traits that could enhance nutritive value of crop residues. The objective was to evaluate nutritive value and hydrocyanic acid potential (HCN-p) of leaf or stem components of crop residues of sorghum lines and hybrids representing differences in phenotypic traits. Four replications of eight or more lines and hybrids made up a randomized complete block design during 2 years in central Texas. Dry matter yield, dry weight loss after extraction in water and incubation in rumen, and fiber concentrations of leaves and stems were measured after grain harvest under field conditions. In addition, HCN-p of axillary branches and mature leaves was quantified. Sample weight loss in water extractions without incubation in rumen was negatively correlated with fiber concentrations, which were measured as the sample weights remaining after extraction in neutral (NDF) and acidic (ADF) detergent solutions. Greater concentrations of water-extractable dry matter and lower concentrations of NDF and ADF were observed for stay-green than for bmr or lines that senesced under drought. Yet, the sum of water-extractable dry matter plus ensuing weight loss during 7 days in rumen, expressed as yield ha−1 of leaf and stem digestible dry matter, was not consistently greater for stay-green than drought-susceptible lines. In addition, the yield of the sum of water-extractable and 7-day rumen losses of stay-green lines was comparable to or less than the bmr line. Under conditions in which leaf senescence varied little, analyses of nutritive value indicated water-extractable dry matter was enhanced and fiber concentrations were reduced in crop residues of stay-green compared to senescent lines. 相似文献
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Afsaneh Nematpour Hamid Reza Eshghizadeh Morteza Zahedi Gholam Reza Ghorbani 《Grass and Forage Science》2020,75(2):169-180
This experiment was conducted to evaluate the effects of two irrigation regimes (control and water stress) and two nitrogen (N) levels (0 and 112.5 kg/ha) on forage yield and silage quality in millet. Bastan (Setaria italica (L.) P. Beauv) and Pishahang (Panicum miliaceum) were sown at two different dates during 2015 and 2016. Both cultivars exhibited reduced dry-matter (DM) yields (45% and 51% in Bastan and Pishahang respectively) due to drought stress. Proline and phenolic contents increased as a result of drought and were significantly and negatively correlated with DM yield and digestibility. Moreover, Pishahang had a reduced acid detergent fibre (ADF) content but improved leaf/stem ratio, digestible dry matter (DDM), relative feed value (RFV), net energy for lactation (NEL), digestibility and silage quality as a result of drought stress, while no significant effects on these traits were observed in Bastan. Silage quality was greatly cultivar-dependent. Both cultivars had higher levels of DDM, RFV and NEL at early sowing dates. Nitrogen supply had greater positive effects on increasing ash, crude protein (CP) content and DM yield under normal irrigation than under water-stress conditions. In summary, given the importance of the energy received per unit of forage from an animal husbandry viewpoint and the significance of DM yield per unit area from an agricultural viewpoint, the obtained results might help farmers in choosing not only the best sowing dates but also proper irrigation and N management practices to achieve their quantitative and qualitative objectives in forage production. 相似文献
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Early-maturing maize (Zea Mays L.) germplasm developed from diverse sources has the potential for use in developing maize hybrids suitable for increasing maize production in the dry ecologies of eastern Africa. A diallel study was conducted to estimate general combining ability (GCA) of 12 early-maturing maize inbred lines, identify potential single-cross hybrids for use as parents, assess genetic diversity among the inbred lines, and relate genetic distance to specific combining ability (SCA) and hybrid performance. Sixty-six F1 diallel hybrids were evaluated under optimal and drought stress conditions at four locations in Kenya and Uganda. The parental inbred lines were genotyped using 94 single nucleotide polymorphism (SNP) markers. Additive gene action was more important than nonadditive gene action for inheritance of grain yield (GY) under optimal conditions. However, nonadditive gene effects were more important in the inheritance of GY under drought and across all environments. Inbred lines CKL0722, VL058014, and CZL0724 were among the best with positive GCA effects for GY across both optimal and drought stress conditions. The correlation between SCA and both genetic distance and F1 GY was significant under both drought stress and across all environments. Inbred lines with desirable GCA effects for GY and other agronomic traits and hybrids with good performance under both optimal and drought stress conditions are potential parents for development of various types of high-yielding, stress-tolerant, and early-maturing hybrids. 相似文献
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《Plant Production Science》2013,16(4):397-408
AbstractStay-green in the post-anthesis period is thought to be an efficient drought-tolerance trait in crops, but its effectiveness in rice (Oryza sativa L.) is unknown. Our objectives were to determine whether the stay-green trait exists in rice cultivars in drought-prone areas. Twenty-four cultivars from Japan and Vietnam were grown in pots of 0.08 m in diameter and 1.00 m deep. At heading, irrigation was terminated in half of the pots and continued in the remaining pots. Every four days during the grain-filling period, we measured the leaf green color with a chlorophyll meter (SPAD), the green leaf area (GLA) and the fraction of transpirable soil water (FTSW). The capacity for maintenance of SPAD-value and GLA in desiccated soils was evaluated by determining the ratio of integrated SPAD-value and GLA in desiccated (D) plants to those in irrigated (I) plants (SPADd/I or GLAd/I, respectively). The SPADd/I and GLAd/I in 24 cultivars showed diverse frequency distributions. Cultivars belonging to higher ranges of the distribution in SPADd/I and GLAd/I tended to show higher ratios of plant dry weight at harvest in D to in I plants. SPADd/I and GLAd/I in the grain-filling period were poorly correlated with those in the seedling period in desiccated soils, and hence the capacity for maintenance of green leaves in the grain-filling period would differ from that in the seedling period. These results suggest that the stay-green trait exists as the capacity for maintaining green leaves and benefits dry matter production in desiccated soils in rice cultivars in drought-prone areas. 相似文献
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《Field Crops Research》2002,74(1):67-79
Field experiments were conducted during two rainy seasons to study the effect of soil moisture deficit on total biomass, pod yield, harvest index (HI) and drought tolerance index (DTI) in groundnut (Arachis hypogaea L.) cultivars possessing a wide range of specific leaf area (SLA, 144–241 cm2 g−1). There were three soil moisture regimes: adequate irrigation (W1), drought simulated under rain-out-shelter (W2) and rain-fed (W3). This experiment had two parts, in one, five cultivars were exposed to W1, W2 and W3, and in a second, seven cultivars were exposed to W1 and W3. Using the same set of seven cultivars, pot-culture experiments were conducted to study relative water content (RWC), stomatal conductance (gs) and single leaf carbon exchange rate (CER) during increasing moisture-deficit in two contrasting (rainy and summer) seasons. Variation in DTI was significant, and low SLA types had greater DTI under both W2 and W3. The ranking of SLA among cultivars was consistent between experiments conducted during the two seasons. The rate of reduction in leaf RWC during the progressive moisture-deficit was related directly to SLA (r=0.78, P<0.01). The coefficient of determination of the slopes calculated between RWC and soil moisture during the experimental period was more in the summer (r2=0.82) than the rainy (r2=0.54) season.Under increasing moisture-deficit, the low SLA types were able to maintain higher RWC, CER and gs in both seasons. The relationships between RWC and CER (r=0.91, P<0.01), and RWC and gs (r=0.65, P<0.01) were significant.It is suggested that under water-limited conditions there is a significant inverse relationship between SLA and RWC. The low SLA types (water use efficient) were found to be drought tolerant in terms of total dry matter production in the field studies, and maintenance of higher RWC under drought like situations in pot-culture experiments. Thus the ability of the low SLA types (higher water use efficiency, WUE) to maintain higher RWC may form the basis for the differences in drought tolerance vis a vis WUE in groundnut cultivars differing in SLA. Suggestions are made to select parents for drought tolerance or WUE, and to initiate breeding to combine traits like high HI, and WUE in terms of lower SLA. Ultimately, selection for both WUE (measured in terms of SLA) and yield traits (HI) should result in cultivars with improved performance in rain-fed agriculture. 相似文献
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不同耐密性玉米品种光合特性对弱光响应的差异 总被引:3,自引:2,他引:1
以郑单958、东单90为试材,研究不同耐密性玉米品种光合特性对弱光胁迫响应的差异。结果表明,正常光照条件下郑单958光合性能优于东单90。郑单958在弱光胁迫后与其正常光照(对照)相比表观量子效率(AQY)增大,光合速率(Pn)、最大净光合速率(P max)、光补偿点(LCP)、光饱和点(LSP)均降低,表现出对弱光的光能利用效率明显高于对照,对强光利用效率较低。东单90在弱光胁迫后与其正常光照(对照)相比AQY降低,P max、LCP、LSP均升高,表现为对强光利用效率高,对弱光利用效率与对照基本相同。叶绿素荧光参数表明,郑单958弱光胁迫后PSⅡ光化学反应中心活性降低、高光强下光能利用效率降低主要是由于叶片光合活性下降;东单90弱光胁迫后对高光强的光利用效率升高的原因是叶片经弱光胁迫后减少了光合过程中的热耗散。 相似文献
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《Plant Production Science》2013,16(3):334-337
AbstractPearl millet [Pennisetum glaucum (L.) R. Br.] is the staple cereal of the hottest, driest areas of the tropics and subtropics. Drought stress is a regular occurrence in these regions, making stress tolerance an essential attribute of new pearl millet cultivars. Recent breeding research has mapped several quantitative trait loci (QTLs) for components of grain and stover yield per se, as well as yield maintenance, under terminal drought stress conditions. We report here the evaluation of these QTLs as possible selection criteria for improving stress tolerance of an elite hybrid cultivar. Initial evaluations, based on hybrids made with topcross pollinators bred from lines selected directly from the mapping population, indicated an advantage to the QTL-based topcross hybrids. This advantage seemed to be related to a particular plant phenotype that was similar to that of the drought tolerant parent of the mapping population. Subsequent evaluations were based on testcross hybrids of drought tolerance QTL introgression lines in the background of the drought-sensitive parent of the mapping population, H 77/833-2. These introgression lines were bred by limited marker-assisted backcrossing of a putative major drought tolerance QTL into H 77/833-2 from the mapping population’s drought tolerant parent. Several of these QTL introgression lines had a significant positive general combining ability for grain yield under terminal stress and significantly out-yielded testcross hybrids made with the original recurrent parent both in unrelieved terminal drought stress and in gradient stress evaluations. 相似文献
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为了研究披碱草属种间杂种抗旱性优势的遗传机理,以加拿大披碱草(J1)、老芒麦(L1)及其种间杂种F1为试验材料,经干旱胁迫处理,采用甲基化敏感扩增多态性(MSAP)方法,探究干旱胁迫后亲本及种间杂种F1的DNA甲基化变化规律。结果表明,亲本材料L1和J1的DNA平均甲基化水平分别为45.41%和59.53%,杂种F1的DNA甲基化水平为44.24%,说明杂种在形成过程中发生了DNA去甲基化作用。全甲基化在杂交种的DNA甲基化模式中占主导地位。干旱胁迫前亲本L1、J1和杂种F1的DNA甲基化程度分别为32.73%、41.54%和28.00%,杂种F1甲基化水平为亲本材料的75.40%;干旱胁迫后各材料的DNA甲基化程度均增加,平均增幅分别为14.99、20.44和19.78个百分点,说明干旱胁迫对不同材料DNA甲基化水平均有明显影响,且具有特异性。杂种F1的抗旱性最强,其DNA甲基化水平低于亲本,说明杂交种的抗旱性与DNA甲基化水平存在一定的负相关。 相似文献
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基于HJ 1B遥感数据的冬小麦旱情监测研究 总被引:3,自引:0,他引:3
为确定植被干旱指数(TVDI)法在苏北地区冬小麦干旱监测中的适用性,利用HJ-1B星CCD、IRS数据,建立地表温度(Ts)-归一化植被指数(NDVI)特征空间,并提取TVDI,对2012年3月26日宿迁市土壤水分信息进行遥感监测,以地面样点实测数据进行验证,评价了地表温度及植被指数信息对TVDI指数变化的敏感性.结果表明,宿迁市较干旱区域主要集中在市、县的城区附近,较湿润区域主要分布在水体周围;TVDI与土壤湿度的相关性随土层深度增加而降低,其中在10 cm、20 cm深度的相关性达到极显著水平;由于Ts直接影响土壤含水量,而NDVI为间接影响,因此TVDI对Ts的敏感性大于NDVI.基于HJ-1B数据的TVDI指数法对冬小麦干旱具有较好的监测效果. 相似文献