Analysis Of The Tarantula Feeding And Evaluation Of The Effectiveness Of Pest Control

Using the dominant species Pardosa pseudoannulata as the predator and the Nilaparavate lugens,Sitobion avenae,and Nephotettix bipunctatus with high incidence and large number of farmland harm as target pests, the best and most optimal combination of environmental factors for the successful predation rate of spider was explored in both natural and artificial ecosystems,two experimental paddy fields in Changsha and Dongkou, Hunan Province,China as natual ecosystem,and three levels orthogonal experiment as man-made ecosystem, using the target pest’s nucleic acid residues extracted from the residue of spider’s digestive tract as template,the speciese and number of target pest were detected and analyed by real-time quantitative PCR. The following results were obtained:1.In the paddy field as natural ecosystem, Pardosa pseudoannulata is the dominant species with hunting widely,preying lots of only living pets,and staying long in the field.There is a strong correlation between the spider and its target pest planthoppers regarding the seasonal ecological distribution(rChangsha =0.6407,r Dongkou county =0.62720).2,The preying process of Pardosa pseudoannulata was affected by the light color, light intensity, and temperature in the microenvironment in the paddy field. Orthogonal test showed that the most significant impact of predation efficiency of the Pardosa pseudoannulata istemperature, followed by light color and light intensity. Further statistical analysis by the three factors and three levels orthogonal test showed that the best condition for Pardosa pseudoannulata’ preying was that temperature is 26 ℃, light intensity 15 Lx, and ambient color is green.3.A method for identifying prey species was Established following qualitative PCR using the DNA fragments remaining in spider’s digestive tract. Based on the method, the DNA fragment of a single species of preying target in spider Pardosa pseudoannulata’s digestive residue can be detected,and the DNA fragment(s) of target(s) that the Pardosa pseudoannulata didn’t feed on cannot be detected.4. The different number of targets( adult Nilaparvata lugens) preyed by Pardosa pseudoannulata was measured following real time qPCR.The results showed that under the general conditions(hunger for 3d,25 ℃), Pardosa pseudoannulata feeded on 3- 4 Nilaparvata lugens.When the temperature was at 25 ℃- 30 ℃, the Pardosa pseudoannulata preyed the maximum amount of Nilaparvata lugens, and above or below this temperature range, its predation decreased. The starvation days and predation has proportional relationship only when the range of starvation time was 5d-20 d in Pardosa pseudoannulata.The above results help us to understand the evolutionaryrelationships between the spider and its prey insects in the process of evolution of biological populations,and to enrich the connotation of spider science in theory.On the application aspect of production,it provides basic information to develop new strategies and measures for conservation and utilization of forests spiders.