【作者】 李晓林；

【导师】 李学军；

【作者基本信息】 西北农林科技大学 ， 作物遗传育种， 2012， 硕士

【摘要】 小麦冷害有冬季冻害和春季冷害，对小麦生产危害较为严重。本研究选择黄淮麦区当前推广面积较大的几个不同类型小麦品种，分4个播期播种，研究播期对冬小麦农艺性状的影响及不同品种越冬期、拔节期抗寒生理的影响，探讨小麦冬季抗冻性与春季抗寒性的关系。取得如下的研究结果：（1）不同类型小麦越冬期至返青期抗寒性差异研究中冬性品种陕229、烟农19在越冬期抗氧化酶活性及渗透调节物质含量较高，膜脂过氧化物含量少，越冬抗冻性最好；半冬性淮麦20、皖麦38及西农979抗冻性略差于冬性品种；弱春性郑麦9023、小偃22及半冬性周麦18抗氧化酶活性、渗透调节物质含量低，膜脂过氧化物含量高，越冬抗冻性较差。返青期各品种抗寒性均减弱，半冬性淮麦20、皖麦38及冬性陕229抗寒性最好，烟农19抗寒性略差；弱春性品种返青期抗寒性最差，半冬性郑麦366、陕麦139抗寒性下降明显。（2）播期对不同品种越冬期抗冻性的影响越冬期各品种不同播期间抗寒性不同。随着播期推后，半冬性周麦18、弱春性小偃22及郑麦9023的抗氧化能力及质膜冷稳定性增强，胞内渗透调节物质含量有部分升高，表明适宜推迟播种有利于提高其抗冻性。冬性陕229、烟农19在10月中上旬播种质膜抗冷性和抗氧化能力较强，抗寒性物质积累较多，越冬抗冻性较好。其余半冬性品种在第二、三播期即10月中旬左右播种表现较好的抗寒性。（3）播期对不同品种拔节期幼穗分化进程的影响随着播期推迟，各品种小花分化期至药隔期发育所需的时间变短，全生育期明显变短。不同品种幼穗发育进程存在差异，弱春性郑麦9023、小偃22及半冬性济麦22、郑麦366返青起身较快，但拔节后期发育较慢，特别是药隔期持续时间长，这可能是它们抗倒春寒性差的重要原因。冬性烟农19越冬抗冻性好，且生产中抗倒春寒性也较好，但其在春季起身较慢，拔节后期发育较快，在生产中霜冻低温后进入药隔期，属于典型的避倒春寒类型品种。（4）播期对不同品种农艺性状的影响随着播期推迟，各品种株高都有不同程度的下降，其中穗下节下降幅度较大，且穗长逐渐变短，第三、四播期穗长下降明显，穗颈长在第三播期开始有部分下降。单株成穗数、千粒重下降明显，和第一播期相比，单株成穗数分别下降了3.5，6.4，8.3个，千粒重分别下降了1.2g，1.6g，2.8g。（5）小麦越冬及拔节不同阶段抗寒生理差异越冬期，冬性陕229、半冬性皖麦38和淮麦20渗透调节物质含量及超氧化物歧化酶活性较高，膜脂过氧化物含量最低，冬季抗冻性表现最好，弱春性小偃22则表现最差，其余半冬性品种冬季抗冻性西农979、陕麦139和郑麦366优于周麦18和小偃22。拔节期，陕229、皖麦38、淮麦20、西农979各抗寒生理指标表现较好，生产中抗倒春寒能力较强；郑麦366、陕麦139在拔节期自然降温及药隔期低温处理时，SOD活性均较低明显，且生产中抗倒春寒能力较差，推测SOD活性可能可以作为小麦抗倒春寒的鉴定指标。小偃22在各阶段SOD活性及WSS含量均较低，但其在药隔期前后Pro含量最高，周麦18在雌雄分化期自然降温后Pro含量高于其它品种，这些可能是二者在拔节期抗寒性好于郑麦366、陕麦139的潜在原因。可见，冬小麦品种春季抗寒性与冬季抗冻性表现不一致，说明小麦越冬期抗冻性和拔节期抗寒性的抗性机理存在差异，春季抗寒性可能是在各生理调节物质的协同调控下进行的。更多还原

【Abstract】 Frost damage in winter and cold injury in spring are the serious hazard of winter wheat inhuanghuai area. Twelve different type of winter wheat cultivars were chosed which werewidely planted in huanghuai wheat production zone, all of cultivars were planted at foursowing date, study on sowing date influence to agronomic characters, and cold resistantphysiology in jointing stage, explore the relationship between frost resistance in winter andcold-resistance in spring of wheat varieties. The results are as follows:(1) Cold hardiness differences of the different cultivars in wintering to green stageIn wintering, antioxidant enzyme(SOD) activity and osmoregulation substances contentof winterness Shan229and Yannong19were the highest, membrane lipid peroxidationproduce(MDA) content was the lowest, the frost resistance of them were the best; frostresistance of semi-winterness Huaimai20, Wanmai38and Xinong979was slightly worsethan the winterness varieties; SOD activity, osmoregulation substances content of springnessZhengmai9023, Xiaoyan22and semi-winter Zhoumai18were low, its chilling resistance ofmembrane was high, frost resistance in winter was poor. In green stage, cold resistanc of allvarieties decreased in different degree, cold resistance of semi-winter Huaimai20, Wanmai38and winterness Shan229were best, cold resistance of Yannong19was slightly worse thanthem; cold resistance of springness varieties was worst, cold hardiness of Zhengmai366andShanmai139decreased significantly.(2) Influence on sowing date to cold resistance in winteringCold resistance of different varieties was different at four sowing date in wintering.Antioxidant capacity and membrane cold stability of springness Zhengmai9023, Xiaoyan22and semi-winter Zhoumai18enhanced with sowing date delayed, osmoregulation substancescontent of them was increased, it means with sowing date postponed, frost resistance of themwas strengthened. If winterness Shan229and Yannong19have good frost resistance inwintering, the best seeding time of was in the early and middle october, in this condition theirability of antioxidant capacity and membrane cold stability were well, substances related withcold resistance content was more. Frost resistance of others semi-winter varieties was good ifthey were planted about mid-october.(3) Influence on sowing date to process of spike differentiation of jointing stage in different varietiesInfluence on sowing date to process of spike differentiation of jointing stage in differentvarieties. With sowing date delayed, duration of floret to anther separation of all varietiesbecome shorter, growth period was significantly shorter. There are differences in spikedifferentiation process of different varieties, springness Zhengmai9023, Xiaoyan22andsemi-winter Jimai22, Zhengmai366raise faster in green stage, but development more slowlyin late jointing stage, especially duration of anther separation was long, its maybe thesignificant reason of they have bad anti-spring cold bility. The frost resistance winternessYannong19was very good, and the anti-spring cold bility was good also, but it raise slowlyin early spring, grow faster in late jointing stage, it could development into anther separationafter frostbite low temperature, so Yannong19was classified the typical eavde spring coldvarietie.(4) Influence on sowing date to agronomic charactersWith sowing date delayed, Plant height of all varieties were decreased differently, lengthof uppermost internode decreased in large amplitude among which, and spike length becomeshorter gradually, spike length declined obviously in the third and fourth sowing date, Fromthe beginning of the third sowing date, the neck length of spike declined. Number of singlepanicles,1000grain weight decreased obviously with postpone sowing date, compared withthe first sowing date, number of single panicles of the second, third and fourth sowing datewas declined separately3.5,6.4,8.3, and1000grain weight decreased separately1.2g,1.6g,2.8g.(5) Cold resistant physiology at wintering and different stages of jointingIn wintering stage: Pro content, WSS content and SOD activity of winterness Shan229and semi-winter Wanmai38and Huaimai20were high, but MDA content was lower,physiological indexes of springness Xiaoyan22were opposite, other cultivars was in themiddle; all of cultivars frost resistance were: Shan229, Wanmai38, Huaimai20were superiorthan semi-winter cultivars Xinong979, Shanmai139and Zhengmai366, semi-winterZhoumai18and springness Xiaoyan22were the last.However, in jointing stage, Cold resistant physiology of Shan229, Wanmai38, Huaimai20, Xinong979were better, and their cold-resistance in spring were better than other cultivars;SOD activity, WSS content of Shanmai139and Zhengmai366were lower in both natural andartificial low temperature, and their ability of anti-spring cold was poor, it could speculate thatSOD activity may be considered as anti-spring cold sign.Although SOD activity and WSS content of Xiaoyan22were low, its Pro content was thehighest in the vicinity of anther separation stage, Pro content of Zhoumai18was higher than other cultivars in floret initiation after natural drop in temperature, these may be latent causesthat the cold-resistance in spring of Xiaoyan22and Zhoumai18were better than that ofShanmai139and Zhengmai366. Frost resistance in winter and cold-resistance in spring wasinconsistent in wheat varieties, which indicate that there are differences in physiologicalmechanism of cold hardiness between wintering and jointing stage, also cold-resistance inspring may be synergically regulated with physiological material.更多还原