Effect Of A Biologically Compound Fertilizer And Its Mechanism On Rice Resistance To Cnaphalocrocis Medinalis Guenee

Cnaphalocrocis medinalis is one of the most important pests in our country,which has outbroken many times,especially in 21st century.For the moment people usually use chemical methods to control Cmedinalis,however,the problems associated with the chemical control methods are deteriorating.In recent years,due to the characteristics of environment-friendly,resources-saving and safety,the microbial fertilizer becomes more and more popular.What we study is a third generation of microbial fertilizer called biologically compound fertilizer.In 2012-2015 years,field application has shown the resistance of rice to Cnaphalocrocis medinalis.In the article,we firstly use the amount of moths and leaf roll to evaluate the rice-resistant performance after the application of the tested microbial fertilizer.Then,for the following test,we evaluate the effect of applying microbial fertilizer at different growing stage and treatments with water and fertilization on rice-resistant performance.To make a thorough inquiry of the phobotaxis,we study the effect of microbial fertilizer on amount of eggs and larvae choice behavior of C.medinalis.We also study the the effect of microbial fertilizer on physiological Characteristics of rice.In terms of antibiotic,we measure the index associated with the growth of C.medinalis,including survival,mortality,weight of 3 and 5 instar larvae,development duration and pupae weight and so on.The experimental results are as follows.1.By comparsion,we find that the amount of moths and leaf roll in fields with the application of microbial fertilizer is significantly lower than the fields without the application.The application results show that 40 days after transplanting(Rice booting stage)may be the best time to use the microbial fertilizer.We also find that use of microbial fertilizer matching the appropriate retention policy,will significantly reduce the demage of C.medinalis.2.After the application of microbial fertilizer,Test using the detached leaves,we find that the application of microbial fertilizer significantly influence the oviposition of adults,the spread of 1 instar larvae and the food choice behaviors of 3 instar larvae.In all varieties of rice,the application of microbial fertilizer significantly reduce the amount of eggs.No matter the spread of 1 instar larvae or the food choice behaviors of 3 instar larvae,the results show the phobotaxis.physiological characteristics of different varieties of rice showed that,the application of microbial fertilizer significantly depress the the width of the blades,but facilitate the blade length and plant height.Furthermore,the application of microbial fertilizer also significantly facilitate the increase of chlorophyll concentration and water content in rice blades.3.Test using the detached leaves,we find that the application of microbial fertilizer significantly influence the survival,mortality,weight of 3 and 5 instar larvae,development duration and pupae weight.Specifically,after 24h,the survival of larvae feeding on microbial fertilizer-treated leaves is significantly lower than control in all 4 rice varieties.After 48h,the survival of larvae feeding on microbial fertilizer-treated leaves is similar to the results of 24h,but the mortality is significantly higher than 24h.Besides,Weight of 3 and 5 instar larvae,pupae weight is both significantly lower than control,whereas the development duration is the opposite.