【摘要】 用光学显微镜和扫描电子显微镜观察水稻广二104、桂朝选两个品种(系)不同粒位小穗分化进度的差异,并研究其与籽粒性状的关系。结果发现直接着生在一级枝梗上的小穗分化顺序有多种类型,而这两个品种(系)主要属于6→5→4&1→3→2。最低位小穗(下称基小穗)比最高位小穗(下称顶小穗)分化早、粒大、结实率高、粒重较重,两者间的 t 值达到极显著的水准。位于内稃两内侧的雌蕊原基出现最早,而位于外稃中轴的分化最迟,在它出现后,浆片原基微突,这些与前人的研宄结果不同。并讨论了它在水稻育种工作中的应用价值。更多还原

【Abstract】 The process of differentiating difference of the spikelet at variouspositions were observed by dissecting binocular microscope and scanningelectron microscope,the characteristics of grain had been investigated.The results are as follows:It was found that the differentiating process of spikelet directlygrowing on the primary rachis branch is in the order of 6-5-4 & 1-3-2.Since the spikelet on the lower position differentiated earlier,it isbigger and heavier than that of the upper position and the percentage offill spikelet is higher too.The top spikelet on the 2nd branch of thesecondary rachis branch differentiated earlier than that of the 1st branch.The stamen primordia on both inside of the palea differentiated earliest,but that on the axis of the lemma differentiated latest,then thelodicule primordia began to appear.So in rice breeding useing variety of such differentiating type as-mmale,it is better to use the pollens which originate from the earliest di-fferentiating stamens of the lowest spikelet growing on the primary rac-his branch.By the way hybrid descendents of transgressive inheritanceof grain weight may be obtained,the process of big-grain breedingwould be shortened.更多还原