Study On The Identification And Resistance Mechanism (Combination) Of Rice Varieties To Brown Planthopper (Nilaparvata Lugens)

Brown planthopper,Nilaparvata lugens(Stal),is one of the most important pests in rice,the popularization and application of rice insect-resistant varieties can not only reduce the yield loss,but also postpone the generation of new-induced pest population.Therefore,the cultivation of resistant varieties(combination)is one of the primary tasks of pest-resistant applications.Through identification of rice resistance to brown planthopper(BPH),the BPH-resistant varieties were screened.The methods of resistance identification were also evaluated,in order to be the effective reference for the future popularization.By using the 304 materials from Agricultural College of Hainan University,2017 Guangxi regional testing,Key Laboratory of crop genetic improvement,Guangxi Academy of Agricultural Sciences,and the insect source from collection of BPH of field and rearing of TN1 in indoor,Standard Seedbox Screening Technique,honeydew amount of BPH,the survival rates and durations of BPH nymphs,feeding and oviposition preference of BPH,contents of secondary substances were used to evaluate the resistance of rice varieties(combinations)to BPH.The major results are as follows:According to the results of Standard Seedbox Screening Technique(SSST),one of 51 rice varieties(combinations)was provided as resistant variety(MR)of the total of Institute of Tropical Agriculture and Forestry,Hainan University.One of 249 materials was provided as resistance(MR)of the total of early and late rice varieties(combination),Guangxi,2017.However,at the repeated experiments,both of them were showed medium sense(MS)or high sense(HS).Among the four kinds of materials provided by key laboratory of the crop genetic improvement at Guangxi Academy of Agricultural Ssciences,R373 was expressed for resistance(R),and the other two were also showed good performance.So it was used for the further determination of physiological and biochemical indexes.There was no significant difference in resistance between R373,Te373,Te582 and RHT,and significant difference with TN1.In the determination of the average honeydew secretion,the results were consistent with SSST.The honeydew amount secreted by brown planthopper was not significant with the amount of honeydew secreted on RHT.The amount of honeydew secreted by R582 and Teyou582 was no significant difference between them.There was no significant difference in the amount of honeydew secreted by R582 and TN1,the difference in the secretion of the honey from TN1 was significantly higher than Teyou582,and significantly higher than Teyou373,R373 and RHT.In the resistance of different rice varieties(combinations)for BPH nymphs feeding selectivity of experiments,the results were consistent with SSST.Within 24h,48h the percentage of each type was not significant difference with TN1,and significant difference with RHT;within 72h,the percentage of nymphs in each species was significantly higher than RHT,R373 and R582 was not significantly different from TNI,the percentage of nymph on the Teyou373,Teyou582 was significantly lower than TNI.In 96h,the percentage of nymph in each species was significantly higher than RHT,the percentage of nymph on Teyou582 was not significantly different from that on TNI,the percentage of nymph on R373,R582,and Teyou373 was significantly lower than TNI.The results showed that the selectivity of brown planthopper was not identical with insect resistance.In the determination experiment of the oviposition of brown planthopper to different resistance varieties(combinations)of rice,the results were consistent with SSST.The oviposition amount of brown planthopper were not significantly different from TNI and R582,Teyou582.There was no significant difference between RHT,Teyou373 and R373.The brown planthopper of the largest oviposition on the TNl and the minimal oviposition is RHT.The results indicated that the rice resistant varieties(combination)had a significant effect on the oviposition selectivity of brown planthopper.the results were consistent with SSST.In the determination of survival rate and developmental stage of BPH of different varieties of rice varieties(combinations),the survival rate of nymphs was the highest on R582,the lowest on the 373.The difference between the survival of Teyou373,R373 and RHT is not significant,the difference between the survival of R582,Teyou582 is not significant with TNl,significantly higher than RHT.There was no significant difference in the survival rate of Teyou582,Teyou373 and R373.During the development period,the development period of brown planthopper nymphs in R582,Teyou582,Teyou373 and R373 was not significantly different from TNl,and significantly lower than the development period of nymphs on RHT.R582 were the shortes,the longest is 373.The results showed that the anti-varieties(combination)had a remarkable effect on the survival rate of BPH,however,were inconsistent with SSST.but the difference at the developmental period between the different species is not significant.At the determination of the secondary substances in different rice varieties(combinations),the results were consistent with SSST.the content of R582,Teyou582,Teyou373,and R373 was significantly different from that of RHT and TNl,the difference between the Teyou582 and R582 was not significant,but the difference was significant with RHT.The content of TNl tannin was the least among the rice varieties(combination),R373 has the highest content.Except for R373,the remaining tannin content is lower than RHT.The total phenol content between and R373,Teyou373 was significant different with TNl,the difference with RHT was not significant.The difference between R582 and TNl was not significant,the difference was significant with RHT.Among them,phenol content of R373 was the highest and the lowest was R5 82.The difference in tannin content of each species was obvious,and there was a great difference between them in total phenol content and insect-resistant varieties.The correlation between the food intake,preference and tolerance of brown planthopper in rice variety showed that Standard Seedbox Screening Technique,the determination of honeydew at the seedling stage,the selective identification of oviposition and the determination of secondary substances of rice could prove the resistance of rice in different degrees.The survival rate and developmental stage of brown planthopper could be used as reference for the preferences of brown planthopper.The results showed that R373,as a stable resistant(R)variety,can be used in cultivating rice resistant to BPH.