【作者】 江洪芝；

【导师】 任正隆；

【作者基本信息】 四川农业大学 ， 生物化学与分子生物学， 2009， 硕士

【摘要】 随着人们生活水平的提高,人们对小麦的品质提出了更高的要求。小麦品质的影响因素很多,包括遗传特性以及栽培措施等。相对于遗传特性而言,栽培措施的研究节省大量的人力物力,同时耗时比较短。因此,栽培措施对小麦品质的影响得到了大量的研究,其中以氮肥运筹最受关注。为了探明不同氮肥运筹对西南麦区普通小麦品质性状的影响,笔者以2个普通小麦品种(系)R210和川农25(CN25)作为供试材料,采用两因素(施氮量及施氮时期)3个水平随机区组设计来研究施氮量及施用时期对小麦品质性状的影响。这些品质性状包括:粗蛋白及蛋白组分含量、湿面筋含量、干面筋含量、面筋指数、微量SDS沉淀值、降落值等常用理化指标,面粉粉质特性指标(形成时间、稳定时间、弱化度、粉质质量指数)以及谷蛋白大聚合体的动态积累规律。主要结果如下:1在不同的施氮量及施氮时期作用下,供试材料的各品质性状变异程度差异较大。两个品种都是以降落值的变异最小,粗蛋白的变异程度紧随其后。而反映面筋质量的面筋指数的变异相对较大,R210和CN25分别达到36.316%,29.314%。面团的流变学特性的指标在两个品种中的变异都较大,除了R210的弱化度之外,其他的指标在两个品种中都超过了10%,最高的达到了33.186%(CN25的形成时间)。总体来讲,流变学特性指标的变异程度大于理化指标。2施氮量及施氮时期对供试材料的理化指标和流变学特性的影响在品种间变化不尽相同。两个品种的蛋白质及其组分含量、干面筋含量、沉淀值、稳定时间、粉质质量指数均随施氮量的增加而提高;谷蛋白大聚合体(GMP)含量、湿面筋含量、面筋指数、降落值、形成时间、弱化度随施氮量增加在品种间的变化不一。施氮时期对品质性状的影响表现为:全施氮肥有利于提高沉淀值、粉质质量指数及醇溶蛋白含量;采用底肥:三叶期肥=1:1的方式,有利于提高GMP含量,但对蛋白质和干、湿面筋的含量以及沉淀值的提高都有阻碍作用;采用底肥:三叶期肥:孕穗期肥=5:2:3的方式,有利于提高干面筋的含量,降低弱化度,但不利于降落值的提高。3籽粒灌浆过程中,两个小麦品种的GMP含量的积累在施氮量及施氮时期的影响下变化不尽相同。随着籽粒灌浆的进程,R210和CN25的GMP含量均呈上升趋势。增施氮肥有利于CN25的GMP含量的积累;氮素过高不利于R210的GMP含量在籽粒灌浆后期的积累;适量增加氮肥的用量有利于籽粒R210的GMP含量在整个灌浆过程中的积累。各种施氮时期下,R210的GMP含量动态积累规律几乎一致(底肥:三叶期肥:孕穗期肥=5:2:3时GMP含量在灌浆末期几乎停止增长),表明,施氮时期对GMP含量动态积累影响非常小;CN25在各施氮时期下GMP含量动态积累规律差异较大,全施底肥是GMP含量的动态积累最佳施氮时期。更多还原

【Abstract】 With the development of people’s standard of living, higher wheat quality is demanded.Many factors can influence the qualities of wheat, including variety Characteristic and cultivation measures,etc.Comparative to variety characteristic, research on cultivation measures not only can economize on a lot of manpower and material resources,but also can save lots of time. So there were many research on effect of cultivated method on quality of wheat.And the most important method is nitrogen application.Aiming to investigate the effects of different nitrogen fertilizer amount and application period on wheat quality in southwest of china, two wheat cultivars (Lines) R210 and CN25 were used to study with three application rates of N, and the random block design was used in the experiment. These qualities characteristic include protein component, dry gluten content, wet gluten content, gluten index.SDS-sedimentation volume, falling number,dough stability time, development time, degree of softening,quality number.Using the same 2 cultivars we studied the effects of different nitrogen fertilizer amount and proportion of topdressing nitrogen on accumula- tion trend of GMP protent. The main results were as the followings:1 With different nitrogen fertilizer amount and application period, there is great difference of the variation extent of wheat qualities.The lowest variation degree in two wheat cultivars was the falling number,the next was protein content.But the variation degree of gluten index which reflects gluten quality is relative big, R210 and CN25 respectively reach 36. 316% and 29. 314%. In two wheat cultivars, the variation degree of indexes of doughy rheology characteristics were big too.Except of degree of softening,others were more than 10%,the biggest was 33.186%. Overall speaking, the variation degree of indexes of doughy rheology characteristics were bigger than physicochemical index.2 The crude protein content, the contents of protein component, dry gluten content, SDS-sedimentation volume,dough stability time and quality number have increased obviously with the amount of nitrogen fertilizer added. However, with the amount of nitrogen fertilizer amount added, the change of GMP content, wet gluten content, gluten index, falling number, development time, degree of softening have not the regularity.The effects of proportion of topdressing nitrogen on qualitis of wheat manifested as: the application of base fertilizer whole may be beneficial to improve SDS-sedimentation volume, dough quality number and glidian content; Using nitrogen topdressing method as base fertilizer whole: three leaf period=1:1,it is beneficial to improve GMP content,but it go against the increase of protein content, dry gluten content, wet gluten content and SDS-sedimentation volume; Using nitrogen topdressing method as base fertilizer whole: three leaf period: booting stage=5:2:3, it is beneficial to improve dry gluten content, reduce the degree of softening, but it go against the increase falling number.3 With the process of wheat grain filling, GMP content showed an increasing tendency in two wheat cultivars.GMP content of two wheat cultivars under all nitrogen treatment showed a ripid increasing tendency in 20-25 days. Since 30 days, the speed is obviously slow. The CN25 showed higher GMP content accumulating ability with the increase of the amount of nitrogen fertilizer applied. However, excessive nitrogen prevents accumulation of GMP content of CN25 in late filling stage. Effects of proportion of topdressing nitrogen on dynamic accumulation of GMP content in R210.And dynamic accumulation of GMP content is most favorable of CN25 by applying base nitrogen whole.更多还原