The Research Of Chinese Cabbage Seed Pre-processed Technology And Pollen Storage Conditions

Seed aging refers to the gradual decline of seed vigor under natural conditions.Its occurrence and development will seriously affect seed quality,which will have a negative impact on subsequent crop yield and quality.Studies have shown that a series of seed pretreatment can effectively improve seed vigor and ultimately promote high-quality crop output.Seed pretreatment technology includes physical,chemical and seed coating methods.In order to study how to effectively improve the germination vigor of aged Chinese cabbage seeds,we selected 9 physical and chemical methods in seed pretreatment technology to treat "Dongbai No.1" aging Chinese cabbage seeds and used single factor treatment method to determine the range of orthogonal test.Then we treated Chinese cabbage seeds with L9(34)orthogonal test design method and determined the seed germination in the process of germination.Through range analysis(i.e.visual analysis)and variance analysis above data and indicators,determine the primary and secondary order of influencing factors,and select the best combination conditions for improving seed germination vigor index.We used the best combination treatment conditions to germinate Chinese cabbage seeds,and then determined the physiological and biochemical indicators of the improved seed vigor,in order to explore the mechanism of different methods to improve the seed vigor.(1)Different physical methods(magnetic field and high voltage electrostatic field)and chemical methods(including polyethylene glycol-PEG,mannitol,gibberellin-GA,6-BA,antioxidant-AsA,CaCl2,KH2PO4)were used to treat aging Chinese cabbage seeds by single factor initiation and orthogonal test.The results showed that all the 9 treatments improved the seed vigor of aged Chinese cabbage in varying degrees.The results of visual analysis and variance analysis showed that the germination vigor of seeds was restricted by different factors,and the main and secondary influencing factors of germination indicators which could reflect the vigor of seeds were also different.(2)According to the orthogonal test results,the best combination of treatment conditions was obtained.Under these conditions,we treated seeds separately,and analyzed and compared the vigor indexes of seeds.Finally,the best way to improve seed vigor was magnetic field treatment in physical method,followed by high voltage electrostatic field treatment and PEG treatment.Plant growth hormone 6-BA treatment had the worst effect.(3)When the seed vigor was increased by different treatments,the physiological and biochemical indexes of 9 treatments would be affected differently.The results showed that the contents of soluble sugar and soluble protein,which were closely related to metabolic activities,increased significantly during the germination of aged Chinese cabbage seeds treated by 9 methods;the content of MDA,the final product reflecting the degree of membrane lipid peroxidation,decreased;and the contents of POD,SOD and CAT in the antioxidant enzyne system were significantly higher than those in the control group.(4)We mixed fungicide 80%tebuconazole and 90%carbendazim with insecticides 70%imidacloprid respectively in different proportions,adding non-main ingredients of matching proportions to compound six different formulations of seed coating agents.Eight formulations including two commercial and six formulations of seed coating agents were used to coat Chinese cabbage seeds.The results showed that the 8 kinds of coating agents could inhibit the growth of bacteria in varying degrees.Among them,the mixture of 80%tebuconazole and 70%imidacloprid 1:1 had the best bacteriostasis effect,and the overall bacteriostasis effect was better than other seed coating agents.In the aspect of improving seed vigor,the treatment result of commercial seed coating agent is obviously better than that of formula seed coating agent.According to the bacteriostasis effect and the improvement of seed vigor,the optimum formula of seed coating agent was formulated by mixing 80%tebuconazole and 70%imidacloprid 1:1.(5)In order to explore the best storage temperature for keeping the vitality of Chinese cabbage pollen,three different temperatures(25?,20?,and 4?)were set up to store Chinese cabbage pollen.The results showed that the pollen viability retention time of Chinese cabbage stored at-20? and 4? was longer than that of the control group at 25?.When the storage temperature was 4?,the pollen viability of Chinese cabbage maintained for the longest time,reaching 2.8 times of the control.