• 作者： 吳大本
• 作者服務機構： 國立臺灣大學植物學系
• 中文摘要： 由 Sorghum purpureo-sericeum 粗絲期染色體分析比較所得資料推測其B染色體可能來自核仁染色體之短臂。鏡檢花粉母細胞和花藥營養層細胞發現若干該等細胞之B染色體有滯留及數目變異的現象，此或因B染色體中節發生輕微缺陷所致。分析趨動期細胞知所含B染色體數目與A染色體之交叉數成正比表示B染色體有助于增進遺傳變異。
• 英文摘要： Pachytene analysis between A- and B-chromosomes of Sorghum purpureo-sericeum indicates thatthe B-chromosomes are probably derived from the heterochromatic short arm of the nucleolar chromo-some through centromere misdivision and subsequent structural changes. The nature and behaviour of B-chromosomes in pollen mother cells and tapetal cells have been studied in detail. The lagging behaviourand the mosaic phenomenon for the B-chromosomes may suggest the presence of defective, though func-tioning centromere. Meiotic analysis of the plants which contain from 0 to 2 B-chromosomes shows thatthe mean chiasma frequencies are significantly higher with increasing numbers of B-chromosomes.
• 中文關鍵字： para-sorghum; pachytene analysis; B-chromosomes; chiasma frequency
• 英文關鍵字： --