玉米胚乳突变基因与互作对籽粒成份的影响——Ⅱ.O_2基因与su_1、sh_2、bt_2、wx基因的互作效应

The Effects of Maize Endosperm Mutant Genes and Gene Interactions on Kernel Components——Ⅱ.The Interactions of o_2 with su_1,sh_2,bt_2 and wx Genes

研究了 O_2基因与 su_1,sh_2,bt_2,wx 基因互作对玉米籽粒百粒重、蛋白质、赖氨酸含量及碳水化合物组分(淀粉、可溶性糖、蔗糖、还原糖、水溶性多糖)的影响。结果表明:O_2与 su_1,sh_2,bt_2,基因互作显著降低百粒重及淀粉含量,增加蛋白质、赖氨酸、可溶性糖、蔗糖和还原糖含量,但增加幅度受遗传背景的影响。与正常型及单突变体相比,籽粒发育过程中这些双突变体一般表现为:粒重增长较慢;蛋白质含量下降幅度较小;淀粉早期含量较低,后期增长缓慢;可溶性糖和还原糖早期含量较高,后期下降速度随基因型而异。o_2 基因与 wx 基因互作对籽粒成份影响较小。研究分析了籽粒各成份之间的相互关系并讨论了这些基因互作对玉米品质育种的利用价值。

The effects of interactions of O_2 with su_1, sh_2,bt_2 and wx genes on 8 kernelcharacters(100-kernel weight,protein content,lysine,starch,soluble sugar,sucrose,reducing sugar,water soluble polysaccharides) were studied.The results wereas follows:The double mutants of o_2 with su_1, sh_2 and bt_2 genes could significantlyreduced 100-kernel weight and starch content,and greatly increase the contents ofprotein,lysine,soluble sugar,sucrose and reducing sugar,but the scope of increase was affected by the genetic backgrounds.The general changing trends of kernel com-ponents during the process of kernel development of these double mutants,whencompared with their normal counterparts and single mutants,could be described asfollows:100-kernel weight increased slowly;the protein content decreased slowly;the content of starch was lower at the early stage and then had a slight increase;thecontents of soluble and reducing sugar were higher at the early stage,then followedby some decreases,but the speeds of decreases varied with different genotypes.Theinteraction of o_2 with wx gene had very little effect on kernel components.Therelationships among different kernel characters were analysed and the practical value ofthe interactions of o_2 with su_1,sh_2,bt_2 and wx genes for the improvement of cornquality were also discussed.