Relationships between different prolamin proteins and some quality properties in durum wheat

The objective of this paper was to study the differences between some prolamin variants coded at the loci Glu-3/Gli-1, Glu-1 and Gli-A2 and their relative roles in durum-wheat quality. F₃ lines from four durum wheat crosses (‘Abadia’בMexicali’. ‘Oscar’בArdente’, ‘Oscar × Mexicali’ and ‘Alaga’בC. of Balazote’) were analysed for gliadin and glutenin composition by electrophoresis. Whole-grain-derived samples were analysed for SDS sedimentation (SDSS) value, mixing properties, and contents of protein and vitreousness. The glutenin patterns LMW-2. LMW-2^? and LMW-2 (CB) at Glu-B3/Gli-B1 were associated with better gluten quality than were LMW-1 and LMW-2*. The glutenin subunits LMW4 and LMW3 + 15 at Glu-A3/Gli-A1 and HMW-1 showed better mixing properties than LMW7 + 12, LMW5 and the null phenotype. respectively. The HMW glutenin subunits 20 + 8 at Glu-B1 showed a negative association with gluten quality, but the rest of the HMW glutenin subunits and α-gliadins did not show any influence on gluten quality. Correlations between the results of the SDSS test and the mixograph were highly significant, but no correlation was found between these results and protein and vitreousness contents. The results are discussed in relation to the development of durum wheat varieties with improved qualities.     

氮肥不同施用方法对小麦生长、养分吸收利用的影响

以超高产强筋小麦为试验材料,探讨返青、拔节与孕穗肥施用比例对氮、磷、钾吸收利用、籽粒产量的调节效应。结果表明:拔节期追施氮肥,产量提高,后期施氮有利于磷、钾素吸收效率和运转效率提高。施氮量为300kghm-2条件下,以基肥、拔节肥比例为7∶3较为适宜。     

Composition and Content of High-Molecular-Weight Glutenin Subunits and Their Effects on Wheat Quality

Sedimentation values, flour glutenin macropolymer (GMP) contents, composition and contents of high-molecular-weight (HMW) glutenin subunits (GS) of 233 flour samples were determined. Our data indicated that subunit 1 occurred more frequently at Glu-A1, subunit pair 7 + 8 at Glu- B1 and 2 + 12 at Glu-D1. The significant relationships between Glu-1 quality score and total HMW glutenin content, sedimentation value and GMP content suggested that the composition of HMW-GS affects wheat quality strongly. Moreover,the total content of HMW-GS was correlated with certain quality parameters more significantly. Relationship between subunit 5 + 10 content and breadmaking quality was better than others, but 2 + 12, 7 + 8, 7 + 9 and 4 + 12 also correlated with certain quality parameters significantly. The contents of total HMW-glutenin, x-type subunits and y-type subunits related with sedimentation value, flour GMP content, and Glu-1 quality score more strongly than that of individual subunit or subunit pair. The flour GMP content, with excellent correlation to sedimentation value, total contents of HMW glutenin, x- and y-type subunits and many other quality parameters, could be an ideal indicator of breadmaking quality at earlier generations for breeding purpose for its simple procedure and small scale.     

氮素运筹方式对沙薄地小麦产量和品质的影响

以优质中筋小麦品种豫麦70为试验材料,研究了沙薄地大田条件下等量氮肥不同运筹方式对小麦产量和品质的影响。结果表明：①氮肥底施 追施优于氮肥全部底施(一炮轰);②在70％氮肥底施的基础上,拔节期重追氮肥的增产效果明显,以20％氮肥拔节期追施,10％氮肥孕穗期追施的产量最高,较氮肥全部底施的增加9．1％;③所有氮肥底施 追施处理的籽粒灰分含量、出粉率、吸水率均比氮肥底施的提高,除硬度以外,所有氮肥底施 追施处理的籽粒品质趋于软质化,表现为蛋白质含量和湿面筋含量降低,沉降值减少,稳定时间、断裂时间缩短,弱化度增大。     

Allelic Variation of Glu-A1, Glu-B1 and Glu-D1 in Chinese Released Wheat Varieties in the Last 50 Years

The high-molecular-weight glutenin subunit (HMW-GS) components from about 85 varieties were fractionated by SDS-PAGE, including 22 corner stone breeding parents, 45 varieties taking important role in Chinese wheat production and 18 varieties with good bread making quality. The 22 corner stone breeding lines carry either null (c) or 1 (a) subunits on Glu-A1 loci. Five types are detected on Glu-B1, which are 7+8(b), 7+9 (c), 14+15 (h), 17+18 (i), 6+8 (d). 7+8 and 7+9 are the two major types. Six types have been detected on Glu-D1, which are 2 + 12 (a), 2 + 10 (e), 5 + 10 (d), 4+ 10 (j), 4 + 12 (c), 2 + 11 (g). 2 + 12 and 2 + 11 are the two major types. In the corner stone breeding lines, early premium from American carries 5 + 10, St2422/464 from Italy carries the 14 + 15. In addition, two relatively essential varieties, Mara and Alondra carry 5 + 10. In the 45 commercialized varieties, sowed more than 666 000 ha (10 million mu) annually, only Yangmai 5 conveys the 5 + 10 on Glu-D1, and Xiaoyan 6 and Yumai 7 carry the 14 + 15 on Glu-B1. Four varieties, Funo, Nongda 139, Zhengzhou 683 and Fan 6 convey the 17 + 18 on Glu-B1. The 18 bread wheat varieties recommended by the Ministry of Agriculture in 1992 could be classified into two groups, 5 + 10 and 14 + 15. Zhongzuo 8131 and its selections are the typical genotype of 5 + 10. Genes coding the two subunits are from either Yecora F-70 or IRN68-181. Xiaoyan 6 and its derivative varieties are the typical genotype of 14 + 15. The genes coding 17 + 18 subunits in Chinese varieties were derived from Funo or its selections. These results basically reflect allelic changes on Glu-1 in Chinese wheatvarieties in the past 50 years. It is also proven that HMW-GS components may have great diversity betweenlines from the same cross, which causes great difference on baking quality.     

面筋持水率与面筋延展性的关系*

 以昆明市面粉市场销售的22种小麦面粉为材料,用手洗法测定湿面筋含量、干面筋含量、面筋持水率和面筋延展性,通过相关分析、通径分析、多元线性回归等方法分析了面筋含量、面筋持水率与面筋延展性的关系。结果表明面筋持水率在不同材料间差异较大,面筋持水率与面筋延展性间存在极显著正相关,相关系数达到0.782^**。通径分析结果表明,湿面筋含量、干面筋含量及面筋持水率对面筋延展性具有明显的直接和间接作用。通过多元线性回归分析得到的面筋延展性与湿面筋含量、干面筋含量、面筋持水率间的多元线性回归方程也较为可靠。因此,面筋持水率也可作为衡量面粉品质的指标之一。     

牛源整合素β_1亚基的克隆及表达载体的构建

参照已公布整合素β1亚基的基因组序列,设计并合成了对克隆引物,以RT-PCR方法从牛肺组织扩增出约2 400 bp的β1基因,经回收纯化连入PGEM-T载体,测序.依照测序结果设计1对原核表达引物,1对真核表达引物,分别以克隆载体PGEMβ1为模板扩增目的片段,经相应的EcoR I、XhoI和EcoR I、XbaI酶切纯化后,在T4DNA连接酶的作用下,定向亚克隆到原核表达载体pET-28a和真核表达载体pCDNA3.1zero(+)中,PCR、酶切鉴定及序列测定表明,成功构建了β1亚基原核表达载体pETβ1及真核表达载体pCDNAβ1.     

氮肥施用时期对弱筋小麦宁麦9号品质的影响

以优质弱筋小麦宁麦9号为材料,研究江苏淮南麦区高产栽培条件下氮肥施用时期对小麦品质的影响。结果表明:在总施氮(纯氮)量为225 kg·hm-2、基肥与追肥比为5:5的条件下,氮肥施用时期对籽粒营养品质、磨粉品质、面粉品质、面团品质及淀粉糊化特性均有显著的调节作用。越冬期及越冬期前施氮,宁麦9号可达到弱筋小麦品质标准,以全基施处理品质最优,4叶期追施处理的产量和优质较协调。     

国产优质小麦的分布及质量状况

简要介绍了我国小麦主产区所生产的优质小麦的分布及生产现状 ,重点概述了各品种优质小麦的品质特性 ,指出了各优质小麦制成面粉后所适宜制作食品的种类 ,借以指导小麦专用粉的生产。     

不同筋力冬小麦品种子粒中若干淀粉合成关键酶活性变化研究

在池栽条件下，研究了3个不同筋力(强筋、中筋、弱筋)冬小麦品种子粒灌浆过程中腺苷二磷酸葡萄糖焦磷酸化酶(AGPP)、可溶性淀粉合成酶(SSS)和淀粉分支酶(SBE)3个淀粉合成关键酶活性的变化．结果表明，3个小麦品种的AGPP，SBE和强筋品种的SSS酶活性变化均呈单峰曲线，花后20d达到峰值；中筋和弱筋品种的SSS酶活性则呈双峰曲线，花后10d和20d分别有两个峰值，且第2个峰值显著高于第1个峰值．表明强筋品种子粒中淀粉合成酶底物含量丰富，淀粉合成可能比较活跃，而中筋和弱筋品种子粒中支链淀粉合成可能比较活跃.