Winter wheat （Triticum aestivum） cultivars Dongnongdongmai 1 with strong cold/freezing tolerance and Jimai 22 with weak cold/freezing tolerance were used for investigating the difference of microstructure and ultras...Winter wheat （Triticum aestivum） cultivars Dongnongdongmai 1 with strong cold/freezing tolerance and Jimai 22 with weak cold/freezing tolerance were used for investigating the difference of microstructure and ultrastructure between leaves of two cultivars under low temperature stress （5℃ and -15 ℃） using optical and electron microscope. The results showed that there was no obvious difference between leaves of Dongnongdongmai 1 and Jimai 22 in microstructure. However, the difference between those leaves was distinct in ultrastructure. The grana lamella and stroma lamella were stacked regularly and arranged parallelly along the long axis of chloroplasts in cv. Dongnongdongmai 1, while the arrangement directions of thylakoids in Jimai 22＇s leaves were so irregular as to form various angles with the long axis of chloroplasts. At -15℃, the mitochondrias were swelled to be round and the structure of cristaes became blurry in both cultivars＇ leaves, while some cristaes of Jimai 22 disappeared. These results would provide theoretical evidence for selecting cold/freezing tolerant winter wheat germplasm resources展开更多
Four varieties of winter wheat with different return green rates were used to analyze the plasma membrane stability and the factors that affect winter wheat in the frigid region during winter. The removal of reactive ...Four varieties of winter wheat with different return green rates were used to analyze the plasma membrane stability and the factors that affect winter wheat in the frigid region during winter. The removal of reactive oxygen species, the degree of plasma membrane impairment, water composition and content, and the changes in cell viability in the crowns, which contain the growing point, were studied during the period from cold acclimation to the deep freezing. The results showed that electrical conductivity which reflects the degree of plasma membrane damaged under low temperature was significantly correlated with the free water and the total water content. The malondialdehyde （MDA） content, which reflects the degree of membrane peroxidation, was very significantly correlated with superoxide dismutase （SOD）, peroxidase, and ascorbic acid. During the deep freezing period, the SOD activity and glutathione （GSH） content of the winter wheat varieties were relative to their cold resistance. During this period, the MDA stability, SOD, GSH, and the total water and the free water content might be used to identify the cold resistance of winter wheat varieties.展开更多
Freezing stress presents a severe threat for winter wheat(Triticum aestivum L.)during overwintering.Dehydration plays a significant role in plant cold-hardiness.In this study,dehydration-related traits were investigat...Freezing stress presents a severe threat for winter wheat(Triticum aestivum L.)during overwintering.Dehydration plays a significant role in plant cold-hardiness.In this study,dehydration-related traits were investigated between highly and tender freezing-tolerant winter wheat cultivars during the overwintering period.Accompanied by a decrease in temperature,the water content in crowns of highly freezing-tolerant winter wheat was significantly lower compared to that of tender freezing-tolerant winter wheat(control).The ratio of free and bound water content had slight changes in highly freezing-tolerant winter wheat,though there were wide fluctuations in the control.The transcript levels of dehydration-related genes were more expressed in the highly freezing-tolerant winter wheat than those in the control under freezing stress.The plant growth also showed significant differences between the two winter wheat cultivars.Based on these results,the study proposed that the highly freezing-tolerant winter wheat produces higher expression of dehydrins under freezing stress,causing additional dehydration in the tissue to avoid cell death caused by the formation of ice crystals.Furthermore,winter hardy cultivar also reduced the percentage of free water content that inhibited plant growth,and regulated the water composition for plant survival under freezing stress.展开更多
Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein...Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein contents,starch damage,swelling power,pasting characteristics,and flour particle size distribution; dough properties determined by a mixograph; and breadmaking properties for pup loaves (100g flour). Only two parameters,the protein content of wheat and the granulation of flour,showed significant correlations with bread crumb grain scores. Protein content of wheat ranging 12.9%～14.5% determined by an NIR method showed a weak inverse relationship (r =-0.61,p<0.05) with bread crumb grain score. Flour particle size distribution measured by both Alpine Air Jet Sieve and NIR methods revealed that the weight wt % of particles less than 38μm in size and representing 9.6%～19.3% of the flour weights was correlated positively (r =0 .78,p<0.01) with crumb grain score,whereas wt % of flour particles larger than 125μm had an inverse relationship (r =-0.60,p<0.05) with crumb grain score.展开更多
Two varieties of winter wheat,Bei Nong 2(B. N. 2)and Jing 411(J. 411),were selected for osmotic adjustment study. At wheat growing stages,from recovery period to mature period,leaf relative water content(LRWC) ,water ...Two varieties of winter wheat,Bei Nong 2(B. N. 2)and Jing 411(J. 411),were selected for osmotic adjustment study. At wheat growing stages,from recovery period to mature period,leaf relative water content(LRWC) ,water potential(LWP)and saturated osmotic potential (LSOP) were positively correlated to soil relative water content (SRWC) and decreased as SRWC descended at each growth stage,and the decreasing range exhibited B. N. 2【J. 411. The turgor pressure(TP)of both the varieties decreased less than LRWC and LWP. It was shown that both varieties had a osmotic adjustment ability(OAA) ,and the decreasing range presented B. N. 2【J. 411. Both the varieties had a TP tubercle in TP vs SRWC graph at heading and filling stages,and their OAA was the strongest at these two stages.展开更多
为了明确黄土旱塬区不同降雨年型下秸秆覆盖量对土壤水温效应和冬小麦产量影响的机理,本研究连续7年研究了秸秆覆盖量在不同降雨年型对土壤水分、温度及冬小麦耗水和产量的影响。结果表明,秸秆覆盖显著提升越冬期地温,覆盖量越大,增温...为了明确黄土旱塬区不同降雨年型下秸秆覆盖量对土壤水温效应和冬小麦产量影响的机理,本研究连续7年研究了秸秆覆盖量在不同降雨年型对土壤水分、温度及冬小麦耗水和产量的影响。结果表明,秸秆覆盖显著提升越冬期地温,覆盖量越大,增温效果逐渐减弱。在干旱年和平水年,返青期1500 kg hm^(-2)处理呈增温趋势,而丰水年则表现为降温;不同年型下,覆盖量越大降温效果越显著。秸秆覆盖在冬小麦生育期内均增加了0~2 m土层的土壤贮水量,且覆盖量越大贮水量越高;干旱年和平水年,耗水量随覆盖量增加而减少,而丰水年则相反。干旱年返青—灌浆期,1500 kg hm^(-2)处理较露地贮水量增加11.8 mm,且全生育期耗水量在各年型下均高于露地6.9~14.8 mm,其中返青—拔节期和灌浆—成熟期的耗水量增加尤为显著。在产量和水分利用效率方面,1500 kg hm^(-2)处理分别较露地增加17.6%和14.8%,增产主要源于穗数增加;3000 kg hm^(-2)处理的产量和水分利用效率与露地接近,而覆盖量进一步增加则导致产量和水分利用效率下降。当1500 kg hm^(-2)覆盖条件下,可有效提高干旱年和平水年返青期土壤温度,达到高产和高水分利用效率,3000 kg hm^(-2)为临界值,过高覆盖量虽显著增强保水效果,但因降温过度,产量和水分利用效率下降。展开更多
基金Supported by Doctoral Scientific Research Project of Northeast Agricultural University (20082010)Innovative Research Team Project of Northeast Agricultural University (CXZ003)
文摘Winter wheat （Triticum aestivum） cultivars Dongnongdongmai 1 with strong cold/freezing tolerance and Jimai 22 with weak cold/freezing tolerance were used for investigating the difference of microstructure and ultrastructure between leaves of two cultivars under low temperature stress （5℃ and -15 ℃） using optical and electron microscope. The results showed that there was no obvious difference between leaves of Dongnongdongmai 1 and Jimai 22 in microstructure. However, the difference between those leaves was distinct in ultrastructure. The grana lamella and stroma lamella were stacked regularly and arranged parallelly along the long axis of chloroplasts in cv. Dongnongdongmai 1, while the arrangement directions of thylakoids in Jimai 22＇s leaves were so irregular as to form various angles with the long axis of chloroplasts. At -15℃, the mitochondrias were swelled to be round and the structure of cristaes became blurry in both cultivars＇ leaves, while some cristaes of Jimai 22 disappeared. These results would provide theoretical evidence for selecting cold/freezing tolerant winter wheat germplasm resources
基金Supported by the Postdoctoral Science Foundation of Heilongjiang Province(2010RCB17)Doctoral Research Startup Foundation of Northeast Agricultural University(LBH-Z10266)+2 种基金New Rural Project of Heilongjiang Provincial Department of EducationProject of Education Department in Heilongjiang Province(12521035)Postgraduate Innovation Project of Education Department in Heilongjiang Province (YJSCX2012-036HLJ)
文摘Four varieties of winter wheat with different return green rates were used to analyze the plasma membrane stability and the factors that affect winter wheat in the frigid region during winter. The removal of reactive oxygen species, the degree of plasma membrane impairment, water composition and content, and the changes in cell viability in the crowns, which contain the growing point, were studied during the period from cold acclimation to the deep freezing. The results showed that electrical conductivity which reflects the degree of plasma membrane damaged under low temperature was significantly correlated with the free water and the total water content. The malondialdehyde （MDA） content, which reflects the degree of membrane peroxidation, was very significantly correlated with superoxide dismutase （SOD）, peroxidase, and ascorbic acid. During the deep freezing period, the SOD activity and glutathione （GSH） content of the winter wheat varieties were relative to their cold resistance. During this period, the MDA stability, SOD, GSH, and the total water and the free water content might be used to identify the cold resistance of winter wheat varieties.
基金Supported by Youth Innovation Talent Project of the General Undergraduate Universities in Heilongjiang Province(UNPYSCT-2018156)。
文摘Freezing stress presents a severe threat for winter wheat(Triticum aestivum L.)during overwintering.Dehydration plays a significant role in plant cold-hardiness.In this study,dehydration-related traits were investigated between highly and tender freezing-tolerant winter wheat cultivars during the overwintering period.Accompanied by a decrease in temperature,the water content in crowns of highly freezing-tolerant winter wheat was significantly lower compared to that of tender freezing-tolerant winter wheat(control).The ratio of free and bound water content had slight changes in highly freezing-tolerant winter wheat,though there were wide fluctuations in the control.The transcript levels of dehydration-related genes were more expressed in the highly freezing-tolerant winter wheat than those in the control under freezing stress.The plant growth also showed significant differences between the two winter wheat cultivars.Based on these results,the study proposed that the highly freezing-tolerant winter wheat produces higher expression of dehydrins under freezing stress,causing additional dehydration in the tissue to avoid cell death caused by the formation of ice crystals.Furthermore,winter hardy cultivar also reduced the percentage of free water content that inhibited plant growth,and regulated the water composition for plant survival under freezing stress.
文摘Samples of 12 hard winter wheats and their flours that produced breads varying in crumb grain scores were studied for 38 quality parameters including: wheat physical and chemical characteristics; flour ash and protein contents,starch damage,swelling power,pasting characteristics,and flour particle size distribution; dough properties determined by a mixograph; and breadmaking properties for pup loaves (100g flour). Only two parameters,the protein content of wheat and the granulation of flour,showed significant correlations with bread crumb grain scores. Protein content of wheat ranging 12.9%～14.5% determined by an NIR method showed a weak inverse relationship (r =-0.61,p<0.05) with bread crumb grain score. Flour particle size distribution measured by both Alpine Air Jet Sieve and NIR methods revealed that the weight wt % of particles less than 38μm in size and representing 9.6%～19.3% of the flour weights was correlated positively (r =0 .78,p<0.01) with crumb grain score,whereas wt % of flour particles larger than 125μm had an inverse relationship (r =-0.60,p<0.05) with crumb grain score.
文摘Two varieties of winter wheat,Bei Nong 2(B. N. 2)and Jing 411(J. 411),were selected for osmotic adjustment study. At wheat growing stages,from recovery period to mature period,leaf relative water content(LRWC) ,water potential(LWP)and saturated osmotic potential (LSOP) were positively correlated to soil relative water content (SRWC) and decreased as SRWC descended at each growth stage,and the decreasing range exhibited B. N. 2【J. 411. The turgor pressure(TP)of both the varieties decreased less than LRWC and LWP. It was shown that both varieties had a osmotic adjustment ability(OAA) ,and the decreasing range presented B. N. 2【J. 411. Both the varieties had a TP tubercle in TP vs SRWC graph at heading and filling stages,and their OAA was the strongest at these two stages.
文摘为了明确黄土旱塬区不同降雨年型下秸秆覆盖量对土壤水温效应和冬小麦产量影响的机理,本研究连续7年研究了秸秆覆盖量在不同降雨年型对土壤水分、温度及冬小麦耗水和产量的影响。结果表明,秸秆覆盖显著提升越冬期地温,覆盖量越大,增温效果逐渐减弱。在干旱年和平水年,返青期1500 kg hm^(-2)处理呈增温趋势,而丰水年则表现为降温;不同年型下,覆盖量越大降温效果越显著。秸秆覆盖在冬小麦生育期内均增加了0~2 m土层的土壤贮水量,且覆盖量越大贮水量越高;干旱年和平水年,耗水量随覆盖量增加而减少,而丰水年则相反。干旱年返青—灌浆期,1500 kg hm^(-2)处理较露地贮水量增加11.8 mm,且全生育期耗水量在各年型下均高于露地6.9~14.8 mm,其中返青—拔节期和灌浆—成熟期的耗水量增加尤为显著。在产量和水分利用效率方面,1500 kg hm^(-2)处理分别较露地增加17.6%和14.8%,增产主要源于穗数增加;3000 kg hm^(-2)处理的产量和水分利用效率与露地接近,而覆盖量进一步增加则导致产量和水分利用效率下降。当1500 kg hm^(-2)覆盖条件下,可有效提高干旱年和平水年返青期土壤温度,达到高产和高水分利用效率,3000 kg hm^(-2)为临界值,过高覆盖量虽显著增强保水效果,但因降温过度,产量和水分利用效率下降。
文摘作物生长模型可以预测不同尺度从站点到区域级别的作物生长和发育,需要逐日天气数据来驱动,随机天气发生器(stochastic weather simulator,SWG)可以满足这一数据需求。课题组根据中国气候特点构建了基于干湿期的随机天气发生器(weather generator based on dry and wet spells,WGDWS),并复现了应用广泛的WGEN(weather generator)类天气发生器(daily weather stochastic simulator,DWSS)。为了评估WGDWS和DWSS生成气象数据作为小麦生长模型输入的适用性,该研究利用中国北方冬麦区8个站点实测57 a逐日气象数据,通过WGDWS和DWSS分别生成300a逐日气象数据,分析两类发生器生成气象要素统计值的质量。结果表明:除山西太原站点外,两类发生器生成的月均最高温、最低温与实测值达到非常好的一致性,太阳总辐射月均值一致性较好,虽然与实测值有一定偏差,但两类发生器生成气象要素月均值与实测值之间均未达到显著性差异。采用作物模型小麦智能决策系统,分别以实测和两类发生器生成数据作为天气输入,评价两种生产管理方式对小麦生长模拟结果的影响。结果表明,WGDWS和DWSS生成数据对小麦产量和生物量均值模拟效果较好,与实测数据模拟值的决定系数分别达到0.94和0.99。总体而言两类发生器对生物量的模拟效果优于产量,模拟生物量的年际变化也小于产量。WGDWS和DWSS对积温、蒸散量和生物量积累的模拟变化趋势高度一致,与实测数据模拟值均未达到差异显著性。两类发生器相比较,除生物量以外,WGDWS模拟生理指标的平均相对误差(mean relative error,MRE)和均方根误差(root mean square error,RMSE)均小于DWSS,WGDWS模拟产量、生物量5%误差以内占比分别比DWSS高6%和25%。进一步分析两种管理方式下WGDWS和DWSS对产量、生物量、物候期等指标的模拟结果,绝对误差和标准差WGDWS优于DWSS的组数分别为63租和57组(总组数均为88组)。两种管理方式下,有14个指标两类发生器之间有显著性差异,其中13个指标WGDWS显著优于DWSS,说明WGDWS比DWSS具有更好的模拟效果。因此WGDWS生成的气象数据完全可用于作物生长模型的天气输入,并且对产量、生物量等指标的模拟性能要优于DWSS。
