三化螟自然种群生命表的研究

Life table of Tryporyza incertulas populatiou

１９８４—１９８８年，在广东省四会县以生命表方法，进行了三化螟自然种群动态的研究，共获９个生命表．从生命表看出，各世代均以初孵幼虫入侵死亡率为最高，中后期幼以初孵幼虫入侵死亡率（ｋ５）为最大，冲后期幼虫转株死亡率（ｋ９）次之，但经图解法和回归法分析结果证实，中后期幼虫转株死亡率是影响三化螟种群数量变动的第１关键因素，而初孵幼虫入侵死亡率乃是第２关键因素．

From 1984 to 1988, nine generations of paddy borer, Tryporyza incertulas, were observed at Sihui county, Guangdong Province and the survival curves of each generations were plotted based on the life table data. The hashest mortality occured at the boring stage of young instar larvae (65.77-80.26% ), and the type of survival curves appeared to be Slobodking IV. The k-values in all life tables show that k9 is highest and k5 is the next. Key factor analysis were conducted with Varley's diagram and Podoler's regression methods respectively. The first key factor was the mortality for transmigration in old instar larvae stage and the second was the invasion mortality in young instar larvae stage.