运用噬菌体随机七肽库筛选与CRN特异结合的多肽

CORYNE（CRN）对拟南芥(Arabidopsis thaliana)茎尖分生组织干细胞的分裂分化的调控具有重要作用。为了研究与CRN胞内激酶区相互作用的肽,探讨与CRN胞内激酶区相互作用的关键位点,本实验采用了亲和淘选噬菌体随机七肽库的方法。通过四轮亲和淘选后随机挑取10个克隆进行DNA测序,经ELISA鉴定后,得到1个与CRN胞内激酶区特异结合的七肽,其序列为TLTELVR。研究结果表明,利用噬菌体展示技术成功淘选到了与CRN胞内激酶区特异结合的七肽,为进一步研究与CRN胞内激酶区相互作用的分子奠定了基础。     

中国和CIMMYT小麦品种Bx7亚基超量表达基因(Bx7OE)的分子检测

高分子量谷蛋白亚基Bx7的超量表达对提高小麦面筋强度有重要作用。利用反相高效液相色谱(RP-HPLC)和STS标记检测了163份中国和CIMMYT小麦品种(系)的高分子谷蛋白亚基Bx7超量表达基因(Bx7^OE)。结果表明,TaBAC1215C06-F517/R964标记和TaBAC1215C06-F24671/R25515标记可分别在含有Bx7^OE基因的材料中扩增出447 bp和844 bp的特异带,在不含Bx7^OE基因的材料中无相应目标带,两个STS标记的检测结果完全一致。在163份小麦品种(系)中,11份品种(系)含有Bx7^OE基因,占总数的6.7%。RP-HPLC与STS标记检测结果一致。利用这两个STS标记可以方便、快速、准确地检测Bx7^OE基因。     

大豆对SMV SC-7株系群的抗性遗传与基因定位

科丰1号×南农1138-2的P₁、P₂、F₁和180个重组自交家系接种SC-7株系群的鉴定表明,P₁与F₁全抗,P₂全感,说明抗性为显性;重组自交家系抗、感按1∶1分离,说明抗性由一对基因控制。利用王永军等的遗传连锁图对SC-7株系群的抗性基因进行连锁分析,将抗病基因Rsc-7定位于N8-D1b＋W连锁群上,并与已定位的5个抗性基因中的3个连锁,还有一个与之相连锁的标记LC5T,其排列顺序和遗传距离为Rsa (30.6 cM) Rsc-7 (22.1 cM) Rn3 (10.3 cM) Rn1 (15.8 cM) LC5T。     

大豆子粒蛋白亚基变异种质的鉴定与筛选

本研究以大豆优良品种中品661的298份甲基磺酸乙酯（EMS）诱变株系和610份大豆品种（系）为试验材料,利用聚丙烯酰胺凝胶电泳（SDS-PAGE）技术,分离大豆种子蛋白并计算各蛋白亚基的相对含量及11S/7S值。研究结果表明,突变群体与自然群体中不同亚基的变异系数差异极显著,但均以β亚基变异范围最大。另外,突变群体的α、β和酸性蛋白亚基的变异范围均大于自然群体。相关性分析显示：11S球蛋白与7S球蛋白含量呈极显著负相关;11S/7S值与蛋白含量相关性不显著,11S/7S值与11S和7S球蛋白各组成亚基均呈显著相关。此外,本研究还筛选出亚基明显变异材料6份,其中Ax亚基突变体尚未见报道,11S/7S值大于3的材料10份,蛋白含量大于48%的材料7份。本研究鉴定和筛选的种子蛋白变异种质为大豆品质相关基因发掘和品种改良提供了材料基础。     

Adaptability and phenotypic stability of Lolium perenne L. cultivars of diverse origin grown at the margin of the species distribution

In northern countries, Lolium perenne L. generally survives poorly when grown inland and north of 60°N because of extensive winter damage. With the projected future climate change, it could become a promising option for improving production efficiency of the agricultural sector in these regions. Here, we compare the biomass production potential of cultivars of diverse origin across five locations stretching from Estonia to Iceland over a period of three harvest years, and their freezing tolerance under artificial conditions. The aim was to relate the observed pattern of adaptation to the geographic origin of the cultivars and their response to prevailing agroclimatic conditions. Significant interactions were observed between cultivars and test environments (locations × years), and significant interactions between cultivars and years were detected at four of the five locations. Models of joint regression, additive main effects and multiplicative interaction (AMMI) and factorial regression using several agroclimatic indices showed that cultivars developed in northern countries showed greater yield potential across the test environments and were, thus, generally better adapted than cultivars from Central Europe. Diploid cultivars were more frost tolerant than tetraploid cultivars giving them an advantage in locations which were characterized by low temperatures during the hardening period in autumn and mild and rainy winters, such as at the Icelandic location. Only a few cultivars showed general adaptability to the environmental conditions at the test sites, the most stable cultivar being an admixture of diploids and tetraploids. In future breeding, the best strategy would be to hybridize cultivars developed in northern countries with more exotic materials that combine high yield potential, adequate winter survival and superior disease resistance under northern conditions.     

Dissection of additive,epistatic and QTL × environment effects involved in oil content variations in rapeseed

In this study, we observed variation of rapeseed oil content in SG population across 11 environments. A joint mapping was conducted to detect the quantitative trait loci (QTL) involved in oil content variation. We examined additive main (a), epistatic effects (aa) and their interactions with environments (QE). Apart from a of 12 QTL (collectively to 6.74% of oil content), aa of 18 locus pairs contributed to 5.36% difference, explaining 45.3% of phenotypic variation in the population. Moreover, 28 QE interactions contributed to a change of 1.55% in oil content in each environment, accounting for 13.3% phenotypic variation. Two environmentally sensitive QTL (OilC2 and OilC8‐1) exhibited a small a (0.17) but strong ae (0.41 and 0.32 averagely). These two QTL were also frequently involved in epistatic interactions. However, two major QTL (OilA7 and OilC8‐2) showed few QE and uninvolved in epistasis. In conclusion, a and aa were the dominant contributors to oil content in rapeseed, while QE accounted for 10‐15% of variation. The results suggest OilA7 and OilC8‐2 are potential candidates for breeding utilization and gene cloning.     

夏播大豆生育期结构对农艺性状的影响

在北京生态条件下，选取生育期在100d以内的我国南方及国外38个大豆品种，进行生育期结构与农艺性状遗传变异方面的研究，试验结果表明：遗传力较高的有大豆主茎分枝始节R1、生育前期、全生育期、荚长、主茎节数、主茎分枝数、单株粒数。筛选出一批对光温反应不敏感、早熟、高产大豆品种。     

waxy基因功能标记开发及在糯玉米育种中的应用

为利用分子标记辅助选择加快糯玉米种质资源改良进程,以糯玉米自交系云539和普通玉米自交系昌7-2为材料,通过DNA序列测定和分析,探明糯玉米自交系云539 wx基因属于wx-D7突变类型。根据2个自交系基因组序列差异,开发出waxy基因功能标记FMD7,并通过了表型验证和通用性验证。利用开发的基因功能标记FMD7进行分子标记辅助选择,结合产量、株型和品质性状分析,获得携带wx基因的优良昌7-2改良系6个。利用本研究开发的基因功能标记FMD7进行辅助选择可加快回交转育进程,提高育种效率,为选育高产糯玉米杂交种提供材料基础,同时也为分子标记辅助选择单基因或少数主效基因控制的性状提供理论参考。     

White lupin (Lupinus albus) variation for adaptation to severe drought stress

This study aimed to reduce the gap of knowledge on white lupin drought tolerance variation, by assessing the grain yield of 21 landraces from major historical cropping regions, one variety and two breeding lines in a large phenotyping platform that imposed controlled severely stressed or moisture‐favourable conditions after an initial stage of favourable growth. Drought stress reduced grain yield by 79%. Genetic correlation coefficients indicated moderate consistency of genotype responses across conditions for grain yield (r_g = 0.76), fairly high consistency for straw yield (r_g = 0.85) and harvest index (r_g = 0.91), and high consistency for flowering time (r_g = 0.99). However, low genetic correlation for yield (r_g = 0.31) occurred among a subset of genotypes with early phenology. Specific adaptation to either condition implied significant (p = 0.05) genotype × condition interaction of crossover type between well‐performing genotypes. Early flowering was an important stress escape mechanism, but intrinsic drought tolerance could be inferred from responses of a few genotypes. Various landraces out‐yielded the improved germplasm under stressed or favourable conditions.