Study On The Effect Of Host Plants On The Ecological Adaptability Of Laodelphax Striatellus Fallén

In recent yearS,the small brown planthopper(SBPH)which has increased sharly and can carry many kinds of virus is pest in Jiangsu province.This pest attracted human's attention because of the rice stripe virus(RSV)which and can infect the rice carried by SBPH.And this disease can result in the crops reduction or zero yield.At present,main factor of SBPH's outbreak is uncertain.Because of high cost,pesticide residue and pollution of controlling this disease,so it's very important to reaearch SBPH ecological characteristics and sustainable control measures.This experiment was analysised with combination of ecology,physiology, extermination of disease and insect pest and so on.In the relationship among the insect,host plants and virus to reaearch the SBPH'regularity of outbreak and carring virus.To provide the foundation in pursuit of the strategy and techniques management for SBPH.In this experiment,SBPH's ecological characteristics and the sustainable control measures were analysed and ecology reasons of outbreak have been illustrated to make every efforts of controlling the pest by ecological measures.Moreover,the difference about SBPH's ecological adaption was researched when rearing the pest in difference host plants by eclolgical and entomological principles.SBPH population's dynamic changes were surveyed when the pest hosted in different host plants respectively in plot and field.Under laboratory conditions,we estabished the SBPH's life table when rearing it in different host plants,and trait of SBPH'S carrier virus were reaearched according to interaction among the pest,host plants,and virus.SBPH population's dynamic changes were surveyed in plot field when the pest hosted in Wu yujing No.3(WYJ-3),Er you No.084(EY-84),Er you No.42(EY-42),Xu dao No.3(XD-3),Yan dao No.8(YD-8),Barnyard grass(BA)and Stephanotis(LE),meanwhile,Its dynamic changes were also surveyed in field when the pest hosted in Wu yunjing No.7(WyunJ-7)and Er you No.084.Above mentioned plants were sort of grass,japonica rice and indica type rice,analysis of date shows that it's not significantly different in plot field,but in field,the investigation indicated that the number of SBPH on japonica rice Wu yunjing No.7 was higher than that on indica type rice Eryou 084.Under laboratory conditions,SBPH population's life cycle was observed which rearing in different host plants,such as Wu yujing No.3,Eryou No.084, Er you No.42,Xu dao No.3,Yan dao No.8,Yang mai No.12(YM-12),Barnyard grass and Stephanotis,then,the SBPH's life table was estabished.The results showed that among eight varieties of host plants,SBPH had the hightest ecological adaptation to Barnyard grass,45.57,which was not significantly different from that on Yandao No.8,but significantly different from that on all the other tested plants.Besides that,the development duration on Barnyard grass was the shortest.And the index on Yandao No.8 was 39.36. The ecological adaptation to indica hybrid rice such as Er you No.084 and Er you No.42 was much lower than that to japonica rice such as Yan dao No.8, Xu dao No.2 and Wu yujing No.3.SBPH showed the lowest ecological adaptation to Stephanotis,the index was 11.04.Different from the results of experimental life table,there was no steady difference on SBPH occurrence in the tested plants.But in field,the investigation indicated that the number of SBPH on japonica rice Wu yunjing No.7 was higher than that on indica hybrid rice Eryou 084.Meanwhile,SBPH population with high virus ratio reard hosted host plants in a complete life circle of plants,and the carrying ratio of the SBPH was tested by DIBA.The results showed that the carrying ratio dropped very quickly when SBPH reared in grass,the second was wheat, japonica rice,and the last is indica type rice.