Ecology Adaptation Of Kerria Lacca Kerr.

In this paper, the author studied biology and ecology of Kerria lacca Kerr. with entomological and ecological method under different kinds of climate in Yunnan Province China. The researches are on adaptivity of Kerria lacca to seven different host trees such as Schleichera oleosa (Lour) Oken, Ficus racemosa L., Zizyphus mauritiana Lam., Acacia montana Benth, Albizia lucidior Nielsen, Flemingia macrophylla (Willd.), Koelreuteria paniculata Laxm. and to seven experimental places such as Yuanjiang, Honghe, Yuanmou, Luchun, Mojiang, Yunxian and Menglian. The major conclusions are as follows:1. Kerria lacca can finish two generations within one year in all experimental places but Yunxian. 2. According to different purpose, come forward three formulas to evaluate lac insect, its host trees, and its adaptivity to host trees, selecting some of the indexes of lac insect as following: density of settlement, sexual ratio, mortality, amount of lac secreted, fecundity, thickness of raw lac and brood-yield ratio.3. Come forward new formula to count mortality of lac insect.There are obvious linear relationship between individual weight and adult density, between adult density and amount of lac secreted by per Kerria lacca on double logarithmic coordinate axis. Kerria lacca secretes lac rapidly after it enters adult stage, and adult embryoism is4. the fastest period of secreting lac. 5. The thickness of periderm and cortex havn't influence on Kerria lacca settling and foraging, but keratinaziation has influence on its settling and foraging. There is direct correlation between the thickness of sclereids and fibres layer and Kerria lacca death. Kerria lacca's mouthparts can reach the secondary phloem of all 7 host trees. The smaller of functional sieve-tube density, the smaller Kerria lacca settlement density, the bigger mortality of Kerria lacca.6. Hereditary property determines foraging behavior of Kerria lacca. Kerria lacca likes to feed on annual branch or younger branch, and the diameter of fed branch ranges from 0.47cm to 1.60cm.When foraging, Kerria lacca has no priority to orientation of branches, but has priority to specific spot on branch bark. Every structure of bark such as tinsel, cork layer, sclereids and fiber can become block for Kerria lacca sucking sap from host tree. The contents of amid, mineral salt between different host trees, inoculated branch and control branch are different, but the entire content of nutrient including sugar, protein, crude fiber, water-soluble material and ash have small difference between different host trees, inoculated branch and control branch. Content of amid of host tree has obvious relationship with thickness of raw lac, mortality and fecundity of Kerria lacca. Content of mineral salt has certain relationship with thickness of raw lac, mortality, fecundity and amount of lac secreted by per Kerria lacca. The entire content of nutrient of host tree has no relationship with thickness of raw lac, mortality and fecundity, but has relationship with amount of lac7. secreted by per Kerria lacca. Kerria lacca feeding can influence the content of nutrient of host tree.8. Alternation can not change density of settlement and sexual ratio of Kerria lacca, but can increase its mortality, amount of lac secreted and fecundity.9. Kerria lacca's suitable temperature is19~24.5℃(average temperature per year), the fittest temperature range is 22.5~24.5℃,≥20℃ days is bigger than 170d, the fittest range is > 240d, the coldest average temperature per month is >11℃, the fittest range is >13 ℃, extreme low temperature is >1℃, the fittest range is >5℃, the temperature vibration within one day is <10℃, the suitable RH range is 50~82%, the fittest range is 50~70%, the suitable rainfall range is 700~1500mm, the fittest range is 700~1000mm. The ratio of temperature to RH can reflect its ecological demand, and its suitable ratio of temperature to RH range is 2~5, the fittest range is2.0~3.5. Among different experimental cites, in different life cycle,...