印度小裂绵蚜在土壤中的垂直分布及其种群消长

【目的】印度小裂绵蚜Schizoneurella indica Hille Ris Lambers是在云南昭通苹果上发现的一种新害虫,发生普遍且严重。研究印度小裂绵蚜种群在土壤中的垂直分布及其消长动态是为了掌握其发生与危害特点。【方法】2002—2006年,我们采用盆栽和田间调查的方法对印度小裂绵蚜在土壤中的垂直分布和种群消长开展了研究。【结果】印度小裂绵蚜田间种群数量高峰期主要集中发生在9—12月,5—7月份为其田间种群快速增长期,种群增长率可达200%~273%。印度小裂绵蚜无翅蚜种群在0~30 cm的土壤范围内占总虫量的49.0%,30~60 cm的占27.0%,>60 cm的占24.0%。无翅蚜的各虫龄全年均有发生,冬季以第4龄若虫和无翅成虫为主。有翅蚜的发生全年只有1个时期,为11月上旬至12月下旬。【结论】印度小裂绵蚜田间种群数量全年发生1个高峰期,主要集中在0~30 cm的土壤范围内,随着土壤深度的增加,印度小裂绵蚜种群数量亦逐渐下降。田间有翅蚜虫量极少,较难观察到。

Vertical distribution in the soil and population dynamics of Schizoneurella indica in apple orchards of Yunnan,China

Objectives] Schizoneurella indica Hille Ris Lambers, a newly reported pest, is widely distributed and has caused severe damage to apple trees in Zhaotong City, Yunnan Province. Research on the vertical distribution in the soil and population dynamics of S. indica was conducted to understand its occurrence and damage characteristics. Methods] The occurrence characteristics and population dynamics of S. indica in apple orchards of Zhaotong City were investigated in experiments conducted in pots and in the field during 2002-2006. Results] The population peak of S. indica was from September to December each year. The population＇s rapid growth period was from May to July and the populatin growth rate was 200%-273%. The proportion of the population of S. indica at soil depths of 0-30 cm, 30-60 cm and 〉 60 cm was 49.0%, 27.0% and 24.0%, respectively. All instars and adults were observed throughout the year, but the fourth instars and wingless adults mainly occurred in winter. Alate aphids occurred only once a year from early November to late December. Conclusion] The 8. indica population has one peak per year, and was found mainly at a soil depth of 0-30 cm. Population density declined with increasing soil depth. The alate aphid population was small and difficult to find in the field.