Seed Germination And Seedling Responses Of Different Cultivated Sugar Beets To Drought Stress

Drought restricts sustainable agricultural development and has become the most important factor affecting the growth and production of Beta vulgaris L.under abiotic stress.The drought resistance of beet at germination and seedling growth stage was weak.This experiment with four different type cultivated beet lines(each cultivation type three materials)as the experimental material,adopt with the method of drought stress of PEG-6000,by measuring parameters of seed germination,seedling growth germination index,physiological and biochemical indexes and mining key genes module,compared different cultivated beet germination and sprout response to drought stress.That provides theoretical basis for further study on drought resistance mechanism of Beta vulgaris L..The main results are as follows.1.With the increase of stress concentration of PEG-6000,the germination rate,relative germination rate,germination potential,relative germination potential,germination index,relative germination index,vigor index,the drought index of all materials showed a trend of decrease,relatively drought damage rate of all materials showed a trend of increase.Seed germination drought resistance suitable concentration at about 15%,medial lethal concentration between 18%?20%,dry lethal concentration between 20%?22%.2.In seedling stage,with the increase of stress concentration of PEG-6000,Beta vulgaris L.growth affected the more obvious.In addition to no significant differences between SOD activity,RWC,Pn,GS,Ci and Tr in the leaves of beet seedlings showed a decreasing trend,MDA content,SS content,POD activity increased,the CAT activity increased first,then turned lower.and the stress concentration,the greater the change,the more obvious.The activities of different enzymes in different cultivated beet leaves were different in response to drought,in which POD and CAT played a leading role.3.There were 385 up-regulated genes and 232 down-regulated genes in the germination stage of KWS2314 seeds.There were 1457 up-regulated genes and 506down-regulated genes at budding stage.In the process,green yellow module,tan module,and dark turquoise module is the key to in response to drought stress art gene module.In the module,DEGs are mainly enriched in five major biological processes,such as,catalytic activity,metabolic process,cellular process,binding,and single-organism process,etc..That are mainly enriched in two pathways of the metabolic pathways and the biosynthesis of secondary metabolites.