澳洲坚果新害虫--脊胸露尾甲生物学习性观察

在云南省西双版纳种植区发现为害澳洲坚果的新害虫——脊胸露尾甲，为准确掌握其生物学习性，在室内以澳洲坚果果仁为食对其进行了饲养，并对各虫态的形态、成虫交配习性、产卵习性、卵的孵化率、各虫态的存活率进行了观察。结果表明：脊胸露尾甲的发育经历卵、幼虫、蛹、成虫四个虫态，其中幼虫分为3个龄期，随着龄期的增长，幼虫体长、体宽和头壳宽度逐渐增加。成虫羽化后不会立即交配，交配前期为（4.65±0.04）d，交配时长不等，初次交配时长为（13.78±0.29）min，雄成虫存在争夺交配权的行为。雌成虫产卵前期为（8.65±0.03）d，初次产卵量为(1.94±0.06)粒，在15:00-18:00时间段的产卵量/小时最高；雌成虫对产卵位置具有选择性，背光面的着卵率极显著高于向光面。卵的孵化率随着湿度的增加而不断提高。常规饲养条件下，卵、1龄幼虫、2龄幼虫、3龄幼虫、蛹的存活率分别为(86.50±0.69)%、(83.31±2.99)%、(94.85±0.71)%、(97.09±1.46)%、(98.77±1.23)%。本研究为脊胸露尾甲的生物学及防治提供参考依据。

Observations on the biological behavior of Carpophilus dimidiatus, a new pest of macadamia nut

Carpophilus dimidiatus (Fabricius), a new pest of macadamia nut, has been recently found in the macadamia plantation in Xishuangbanna, south Yunnan, China. To accurately understand its biological behavior, the morphology of different developmental state, adult mating behavior, oviposition characteristics, egg hatching rate and survival rate of different state of C. dimidiatus were investigated indoors after being fed with macadamia nut. Results showed that the development of C. dimidiatus went through four stages of egg, larva, pupa and adult. The larva had three instars, and its body length, body width and head width were gradually increased with the increasing of instars. Adults did not immediately mate after its emergence, the premating period was 4.65±0.04 d (SE), with a variable mating time, the average length of the first mating time was 13.78±0.29 min, while competition did occur between males to mate with females. The oviposition prophase of female adult was 8.65±0.03 d, averaged with 1.94±0.06 eggs for its first-oviposition. The highest oviposition was between 15:00 and 18:00 per day, with a selection preference to the spawning position, the egg landing rate was significantly higher in the backlit side than in the light side. The egg hatching rate was gradually increased with the increasing of humidity. Under the conventionally feeding conditions, the survival rate of eggs, 1st instar larvae, 2nd instar larvae, 3rd instar larvae and pupae were 86.50±0.69 %, 83.31±2.99 %, 94.85±0.71 %, 97.09±1.46 % and 98.77±1.23 %, respectively. Results from this present study can provide a basic reference for the biology and control of C. dimidiatus in macadamia plantations.