小麦种质资源耐深播性评价体系研究

为建立准确、简单易行的种质资源耐深播评价体系,以15份耐深播能力存在不同程度差异的小麦种质为材料,在大田环境下,研究6个播种深度(5 cm、7 cm、9 cm、11 cm、13 cm、15 cm)下小麦出苗率、出苗时间、苗高、地中茎长、胚芽鞘长、胚芽鞘横截面积及初生根长的差异,筛选小麦耐深播评价的最佳播种深度及其密切相关性状指标,并采用加权耐深播系数法对15份小麦种质进行耐深播综合评价。结果表明,11 cm播种深度能够较好地区分不同小麦种质出苗率差异,可作为小麦种质耐深播评价的最佳深度。在11 cm播种深度下,15份小麦种质的出苗率与出苗时间、苗高、胚芽鞘长、地中茎长存在显著或极显著相关性,可作为小麦种质资源苗期耐深播性评价的主要评价指标;采用加权耐深播系数法将15份小麦种质划分为4个耐深播等级。研究结果将为小麦耐深播育种及机理研究提供重要的理论依据和种质材料。

Study on Evaluation System for Deep-Sowing Tolerance of Wheat(Triticum aestivum L.) Germplasms

Establishing an accurate and simple evaluation system for wheat germplasms is the prerequisite work for the breeding of deep-sowing tolerant wheat varieties. In this experiment,15 wheat germplasms with significant differences in deep-sowing tolerance were used as materials in the field conditions. The emergence rate,emergence time,seedling height,stem length,length of coleoptile internode,coleoptile length,cross-sectional area of coleoptile and length of primary root were investigated to screen the suitable sowing depth and closely related indices for evaluation of deep-sowing tolerant germplasms. The results showed that the 11 cm sowing depth was suitable for distinguishing the difference of the germination rate in 15 wheat germplasms,and can be used for the evaluation of wheat germplasms for deep-sowing tolerance. At the 11 cm sowing depth,the germination rate of 15 wheat germplasms were significantly correlated with emergence time,seedling height,length of coleoptile internode and coleoptile length.These indices can be used as the main indices for evaluation of deep-sowing tolerant germplasms. The 15 germplasms were divided into 4 deep sowing-resistant grades using weighted deep-sowing resistance coefficient. The results of this study will provide important germplasm materials and theoretical basis for breeding deep-sowing tolerant wheat varieties and studying deep-sowing tolerance mechanism in wheat.