苜蓿生卡螨种群参数对温度的响应OA北大核心CSTPCD

The occurrence of subterranean pests in alfalfa (Medicago sativa) fields has become one of the major constraints of alfalfa quality and yield.Sancassania alfalfa,which was identified and described based on its morphology and molecular markers,is a newly discovered pest mite that causes serious damage to alfalfa roots.The occurrence of this pest reduced the growth,yield,and quality of alfalfa at the Jiuquan alfalfa base in Gansu Province.To date,little is known about the population biology of this pest.To explore aspects of the population biology of this pest,its growth,development,and fecundity were determined under a range of temperatures in an artificial incubator.The insects were kept in the dark and supplied with dry yeast as feed,the relative humidity (RH) was maintained at (90±5)％,and the temperature was controlled at 15,20,25,30,or 35 ℃.The results showed that the eggs did not hatch at 35 ℃,and only a few the mites survived to the larval stage at 15 ℃.In contrast,S.alfalfa successfully completed egg-to-adult development at temperatures of 20-30 ℃ .The developmental period of immature stage female mites was 19.42,16.98,and 9.91 days,and that of immature stage male mites was 18.50,16.31,and 10.16 days at 20,25,and 30 ℃,respectively.As the temperature increased,the lifespan of female and male mites became progressively shorter and differed significantly between 20 and 25 ℃ (P<0.05).The duration of each developmental period shortened as the temperature increased,and the longevity of female mites was significantly greater than that of male mites at the same temperature (P<0.05).The mean total spawning and daily spawning values were highest at 25 ℃ and differed significantly between 20 and 30 ℃ (P<0.05).The highest net reproduction rate (R0),233.3,was at 25 ℃.The mean generation time (T) was longest at 20 ℃ (26.24 days) and shortest at 30 ℃ (14.07 days).The maximum innate rate of increase (rm) was 0.329 at 30 ℃.These results provide basic data for indoor-reared S.alfalfa,and lay a foundation for devising strategies to control this important alfalfa pest mite.