Study On The Competition Between Different Species Of Liriomyza Sativae And Liriomyza Trifolii

Liriomyza sativae Blanchard and Liriomyza trifolii (Burgess) is the2worldwide quarantine pest of crops harm vegetable, flowers etc. Due to the characteristics of higher host species wide, short generation cycle, spread fast, strong resistance and reproductive capacity. Easily outbreak has brought great difficulties to the prevention and control work. In recent years, these two kinds of Liriomyza on China’s agricultural economy caused a huge loss, about the increase in China about the hazards of the two leafrniners, especially after the L trifolii, Compared with the L sativae, host range wider, stronger ability of anti pesticide, reproductive interference effect is bigger, at the same time, resistance to high temperature and low temperature is more widely, Therefore, L.trifolii has hazard potential is greater than L. sativae. This article mainly from the two leafminers several possession of resources order, intraspecific and interspecific density dependence, mutual interference reproduction, niche determination and field survey of population dynamics and other aspects, to study the two leafminers interspecific competition and alternative mechanism, provide the theoretical basis for clarifying two leafminers in China interspecific competition and replacement mechanism, but also for the prediction of the two leafminers and provide a reference to replace the distribution in China and the effective prevention and cure.Reviewed the two leafminers damage and distribution in our country, the biological characteristics of their own, it caused huge losses in our country agriculture, are also introduced the development of the relationship between two kinds of Liriomyza mutual competition and alternative. Study on the resources of competition sequence of the two leafminers fecundity and interspecific, The results show that, in the resource space is superior, L. sativae preempt resources space had no significant effect on L. trifolii intrusion and competitiveness, Conversely, if the L. trifolii priority to occupy the space resources, it can significantly limit of L.sativae intrusion and competitive ability.Analysis of the impact of egg density and larval density of two leafminers competitiveness, The results showed that the egg density of two kinds of leafminer eggs survival and growth had no obvious effect. The larva density increase to a certain extent, can significantly reduce the pupation rate and eclosion, reduced pupal weight, shorten the adult longevity and reduce female fecundity, serious impact on the number of two types of Liriomyza F1generation. In the research of two leafminer larvae to competition for food resources, In comparison, the higher density of larvae of F1generation of L.trifolii has greater proportion, feeding on L.trifolii larvae and anti jam ability is stronger, therefore Liriomyza trifolii have stronger competitiveness.Study on the interference capability of the two leafminers between each other, Conclusion the two leafminers exists obvious reproductive interference in between. The male and female L.sativae reproductive interference exists in a certain degree of L.trifolii, Ability of interference number of adult more bigger on impact, in the same number of adults under jamming, The interference ability of male is stronger than female; On the contrary, L.trifolii also have strong reproductive interference ability of L.sativae, An equal number of adult interference, the male or female reproductive interference ability is higher than L.sativae. The results also indicate that reproductive interference phenomenon of the two leafminers only to reduce the population number of offspring, does not affect the growth and survival rate.Measurement results show that the niche, L.trifolii niche width is wider, niche overlap index are very small, niche proportional similarity is very high. Natural enemies of Opius biroi Fischer of the leafminer follow ability is stronger, more like the selection of L.sativae parasitic, Field cage experiments show that, in the absence of pesticide, parasitoid populations of Opius biroi Fischer can be very good control of L.sativae.From2005to2013, the population dynamic tracking survey of two species of Hainan province for8years showed that, population of L.trifolii increased year by year, To2013March survey, L.trifolii has become the dominant population in some areas of Hainan Province, and has continued to expand the trend to replace. In the Hainan province of L.trifolii and L.sativae is latent flies absolute dominant species, The two kind of leafminer population interaction occurs, from February to April is the explosive growth season, This period of L.trifolii was the dominant species, it harm for an important economic to crop, towel gourd, beans, cowpea, Sauteed Green Beans plant damage rate and leaf rate can reach100%, From May to December, two leafminer populations are lower, but the two sponge on gourd and cowpea plant hazard rate almost at the70%. It is eating cowpea in L.trifolii, its year-round population is higher than that of Liriomyza sativae;It is eating the towel gourd in L.sativae, its population of slightly higher than that of L.trifolii in Septemper to December, From the beginning of January, the population of L.trifolii soared more than L.sativae and become the dominant population until in late May.