谷子育成品种萌芽期耐冷性综合评价OA北大核心CSTPCD

Heilongjiang province,located in high latitudes,frequently experiences cold damage during the germination period of millet after sowing.This leads to slow and uneven emergence,as well as insufficient seedling growth,which is a key limiting factor for millet yield and quality in this region.Identifying the cold tolerance of millet and screening appropriate evaluation indi-ces for cold tolerance can provide a theoretical foundation for breeding cold-tolerant millet varieties.It holds great significance for ensuring the safe production of millet.In this study,52 foxtail millet cultivars were selected as research subjects.Twelve cold stress treatments were applied during the germination stage,and the suitability of using germination rate as the index for evaluat-ing cold tolerance at this stage was explored.Following low-temperature stress,the cold tolerance coefficients of seven indices,including germination potential,germination rate,germination index,bud length,root length,bud fresh weight,and root fresh weight,were measured.Comprehensive evaluation of the tested varieties'cold tolerance was conducted using membership func-tion analysis,principal component analysis,correlation analysis,and cluster analysis.Stepwise regression analysis was employed to establish a regression equation for predicting cold tolerance.The results revealed that the germination rate of millet varieties exhibited the largest variation range after seven days of low-temperature treatment at 8℃.This treatment effectively distinguished the differences in cold tolerance among varieties and proved to be the most suitable condition for evaluating cold tolerance during the germination stage.Following low-temperature stress,all seven evaluated indices showed lower values compared to the control treatment at 28℃,although the degree of reduction varied among the indices.Through principal component analysis,the seven individual indices were transformed into three independent comprehensive indices.It was found that bud length,bud fresh weight,and root fresh weight best represented the response of millet during the germination period to low-temperature stress.These indi-ces can be used for evaluating cold tolerance during the germination stage.Cluster analysis categorized the 52 millet varieties into three groups,identifying 17 highly cold-tolerant varieties such as Nenxuan 14,Chaogu 14,and Mengheigu 8,as well as 15 cold-sensitive varieties such as Lugu 7 and Jingu 20.These varieties serve as valuable germplasm resources for breeding cold-tolerant millet and enhancing millet production.