Study On Field Fluctuation Of Fruit Fly And The Application Of Biological Control

Study on the typhoon influence on the law of activities and population dynamics of Bactrocera dorsalis (Hendel), and the research results showed that: on the day when typhoon landed, the number of trapped Bactrocera dorsalis (Hendel) was smaller than that before typhoon's landing; while on the first day after the typhoon or after the rain brought by typhoon stopped, the Bactrocera dorsalis (Hendel) activity reached a peak. The number of trapped Bactrocera dorsalis (Hendel) in each increased a lot every day. Analyze the relation between the dynamic change of Bactrocera dorsalis (Hendel) and meteorological factor on Changtai Wusi Farmland from 2007 to 2009.The analysis result showed that: in the year of 2007, the population quantity of Bactrocera dorsalis (Hendel) on Changtai Wusi Farmland was closely related to the change of mean monthly temperatures, mean monthly maximal temperatures, mean monthly minimal temperatures, monthly extreme minimum temperatures and monthly rainy days. In 2008, the population quantity of Bactrocera dorsalis (Hendel) on Changtai Wusi Farmland was closely related to the change of monthly total precipitation and manly rainy days. In 2009, the population quantity of Bactrocera dorsalis (Hendel) on Changtai Wusi Farmland was closely related to the change of monthly total precipitation. Investigate the Bactrocera dorsalis (Hendel)dynamics in the guava orchard and banana orchard on Tianbao Wufeng Farmland from June 1st to December 21st, 2010 and the results came that the Bactrocera dorsalis (Hendel) dynamics in the guava orchard only had a peak, the peak appeared from the early September to the early October. Bactrocera dorsalis (Hendel) dynamics in the banana orchard had two peaks, the peak appeared respectively in the late August and from the late September to the early October. Meanwhile investigate theBactrocera dorsalis (Hendel) dynamics in and out of the guava orchard on the Wufeng Farmland, it indicated the remarkable difference. Investigate the Bactrocera dorsalis (Hendel) dynamics in urban district of Zhangzhou, in urban-rural fringe zone and in the rural orchards, and it indicated that: most of the investigation time, the population quantity in central Zhangzhou was higher than that in urban-rural fringe zone and the rural orchards; only from early June to early July, The dynamics in rural orchards was always the lowest.The related analysis showed that the population quantity in Zhangzhou urban-rural fringe zone and that in the rural orchards had remarkable linear positive correlation. The results of research on the field release of the sterile male Bactrocera dorsalis (Hendel) gender strain showed that the effective distance for field release is 50 meters. The regression equation between egg hatching rate and release distance was y=0.342x+63.306, and the coefficient of determination was R2=0.924. The relation between egg hatch rate and time was that: the field hatch rate presented a down- up, and the up- down trend as time went by. The changing period was seven days. The field release's effect illustrated that the sterile worms could decrease the population quantity of wild Bactrocera dorsalis (Hendel) efficiently and reduce the population base of the next generation.Use prima protein mixed with malathion, imidacloprid and Dushawei to trap the male and female worms of Bactrocera dorsalis (Hendel), Bactrocera cucurbitae (Coquillett), and Bactrocera tau (Walker), and the prima and imidacloprid blend solution proved the most efficient. Compare with 20% fly protein baits solution, use fly protein baits mixed with malathion, imidacloprid and Dushawei to trap the male and female worms of Bactrocera dorsalis (Hendel), Bactrocera cucurbitae (Coquillett), and Bactrocera tau (Walker), and it showed: the effect of fly protein baits+imidacloprid, fly protein baits+malathion, and 20% fly protein baits solution to trap Bactrocera dorsalis (Hendel) female worms were notably better than that of fly protein baits+Dushawei; the effects of fly protein baits+imidacloprid and CK 20% fly protein baits to trap Bactrocera dorsalis (Hendel) male worms were better. Use prima protein and malathion blend solution to spot spray and the results showed that the effect on pomelo fruitretention was remarkable (P=0.027<0.05). The effect of furitretetion was 64.71%. Use fly protein baits and imidacloprid blend solution to spot spray and the result showed that the effect on guava fruitretention was extremely remarkable (P=0.004<0.01). The effect of fruitretetion of spot spraying every other line was 77.78%, and that of spot spraying every two lines was 50%.Study on the influence of the different distances between cotton temts core and liquid level on trap effect, and the result showed that the both were unrelated. The trap effect on male Bactrocera dorsalis (Hendel) between ME-G1 and ME-G2 showed that the both had no remarkable difference. The trap effect on male Bactrocera dorsalis (Hendel) between ME-G1 and Well-Net showed that the both had no remarkable difference. Research on the trap effect of three kinds of gluing insect gums on male Bactrocera dorsalis (Hendel) , and the results showed that the effect of Well-Net was remarkably better than that of ME+gluing insect gum, and extremely better than that of pure gluing insect gum. The trappers in different colors had different influence on trap effect. And the results showed that the trap effect of orange and sky blue home-made trappers were better than that of transparent trappers.The trappers in the other colors had no remarkable difference. The research results of Well-Net's duration indicated that its duration was 54 days. Compare the numbers of trapped worms under tree shadow and that at the direct sunlight places, and the results showed that the number under tree shadow was remarkably more than than that at direct sunlight places.Examine the dynamics of Bactrocera dorsalis (Hendel),Bactrocera tau (Walker) and Bactrocera cucurbitae (Coquillett) in bitter bourd filed, and the results showed that the harm degree of the three kinds of flies was: Bactrocera dorsalis (Hendel)>Bactrocera cucurbitae (Coquillett)>Bactrocera tau (Walker).