PEG模拟干旱胁迫下花椰菜种质资源萌发特性及抗旱性评价

为鉴定和筛选花椰菜耐旱种质资源,以12个花椰菜种质资源为试验材料,测定不同浓度PEG[0(CK)、100、150和200 g·L^-1]模拟干旱胁迫对花椰菜的相对发芽率(RGP)、相对发芽势(RGR)、相对发芽指数(RGI)、相对活力指数(RVI)、相对苗高(RSH)和相对根长(RRL)等6个指标的影响,并采用隶属函数法进行抗旱性的综合评价。结果表明,100 g·L^-1PEG胁迫对花椰菜种子萌发的影响不大,150~200 g·L^-1PEG胁迫则显著抑制花椰菜种子萌发。100~150 g·L^-1PEG胁迫对RRL具有一定的促进作用,而150~200 g·L^-1 PEG胁迫则会明显抑制RSH,表明150~200 g·L^-1 PEG可作为花椰菜萌发期抗旱性筛选的适宜浓度。基于RGP、RGR、RGI、RVI、RSH和RRL 6个指标,通过隶属函数法综合评价发现,12个花椰菜材料的抗旱性依次表现为P3>P6>A1>P8>P7>P2>P1>P4>P5>A2>A3>P9。本研究结果为花椰菜抗旱品种选育提供了一定的理论依据。

Germination Characteristics and Drought Resistance of Cauliflower Germplasms Under PEG Simulated Drought Stress

Twelve cauliflower materials were used to evaluate their drought tolerance by examining their relative germination percentage (RGP), relative germination rate (RGR), relative germination index (RGI), relative vigor index (RVI), relative seedling height (RSH) and relative root length (RRL) under different PEG concentrations including 0(CK), 100, 150 and 200 g·L^-1 by method of subordinate function. The results showed that, 100 g·L^-1PEG stress presented lower effect on seed germinating, while 150~200 g·L^-1PEG stress significantly inhibited seed germinating. The 100~150 g·L^-1PEG stress had a promoting effect on RRL, while 150~200 g·L^-1PEG stress presented significant inhibition on RSH. Therefore, 150~200 g·L^-1 PEG was most suitable for screening drought resistance of cauliflower at germination stage. According to comprehensive evaluation of subordinate function method based on RGP, RGR, RGI, RVI, RSH and RRL, the drought resistance of the 12 cauliflower materials followed the order of P3>P6>A1>P8>P7>P2>P1>P4>P5>A2>A3>P9. These results provide theoretical evidence for breeding of drought resistance in cauliflower.