提型杂种小麦灌浆特性的研究

STUDY ON GRAIN FILLING CHARACTERISTICS OF HYBRID WHEATS WITH T.timopheevi CYTOPLASM

利用3×5不完全双列杂交的T质杂种(A×R)与对应的A质杂种(B×R)研究了杂种小麦的灌浆过程,结果表明:T质杂种和A质杂种的灌浆特征以及粒重都无显著差异。尽管多数A系上生产的F_0籽粒饱满度较差。但这种不利效应并未在F_1籽粒上表现出来。籽粒发育过程中。D_1、(?)和(?)与千粒重呈极显著正相关。杂种小麦恰好是在这三个因素上表现出明显的优势,优势强度主要取决于亲本的一般配合力和性状水平。文中还对改进杂种小麦的灌浆特性、提高粒重优势的可行途径进行了讨论。

Two kinds of wheat hybrids with the same nuclei but different cytoplasms (one with T.tim-opheevi cytoolasm, i.e. A/R, and the other with T.aestivum cytoplasm, i.e. B/R) were produced from two 3×5 incomplete diallel crosses of 3 A-lines, 3 corresponding B-lines and 5 R-lines respectively. Experimental results showed that there were not significant difference between the hybrids of A/R and B/R in grain filling characteristics and grain weight. Although the seeds set on most A-lines had poor plumpness, such a phenomenon was not found in grains set on F1. During the development of grains, D1, FR2 and FRs were significantly and positively related to 1000-grain weight. It was in these factors that hybrid wheats displayed apparent heterosis. The intensity of heterosis was primarily determined by the general combining ability pnd character level of parents. Methods for improving gtain filling characteristics and increasing heterosis of grain weight in hybrid wheats were discussed.