四倍体与二倍体西瓜子叶不定芽形态发生过程研究

Organogenesis of the adventitious buds from autotetraploid and diploid watermelon cotyledon

为了探讨四倍体与二倍体西瓜子叶不定芽形成的异同,以XYXC、91E7和郑-3的二倍体及其同源四倍体子叶作外植体,在MS+6-BA2.0mg/L培养基上诱导不定芽。在子叶接入培养基后的2、4、6、8和10d分别取样进行石蜡制片,观察不定芽形成过程中的细胞组织学变化。结果表明,子叶诱导不定芽发生是内起源的,即发生于子叶的深层组织—维管组织周围。且4x4～8d形成芽结构,而2x8～10d才形成芽结构。

Adventitious bud development from cotyledons of tetraploid and diploid watermelon was studied using cotyledon tissue of diploid watermelon varieties of XYXC,91E7 and Zheng-3 and their autotetraploids. The cotyledon tissue of experimental varieties was used as explants cultured on MS medium supplemented with 6-BA 2-2.5 mg/L. The initiation of adventitious bud organogenesis and histological changes were observed at 0,2,4,6,8 and 10 days in culture. The results show that the adventitious bud differentiation was originated from deep tissue of cotyledon-around vascular tissue in cotyledon of 91E7, XYXC and Zheng-3. The adventitious bud formation of 4x started 4 to 8 days in cultures, was earlier than that of 2x that started 8-10 days in culture.