The guava weevil, Conotrachelus psidii Marshall (Coleoptera: Curculionidae), is a key pest in guava and information concerning the bioecology of this insect is scarce. This work aimed to verify the bioecology of certain aspects of this insect's lifecycle by observations of the period during which the larvae abandon the fruits in order to enter the soil to pupate, the effect of different soil types on penetration times and the subsequent emergence of adults from the soil. Adult population levels were monitored over a two year period and the possible relationship between population density and climatic factors investigated. The abandonment of guava fruits by the larvae was evaluated during two time periods (day-time and night-time). The time taken for 4th instar larvae to penetrate 3 different soil types was observed. The time these insects remained underground and subsequent adult emergence periodicity was evaluated following the release of 4th instar larvae into trays filled with soil. These trays were maintained in the field and observations carried out three times a day (morning, noon, and afternoon). Path analysis was used to investigate the relationship between the climate variables and adult population density. Soil penetration by 4th instar larvae was fastest in clay soils and slowest in sand. There was no difference (p = 0.075) between the number of larvae that abandoned the fruits during the day (51%) and during the night (49%). A majority of the adults emerged from the soil during daytime (86.84%), which was significantly different (p < 0.001) to the number of adults emerging during the night (13.16%). When comparing adult emergence during different periods of the day, the majority emerged in the afternoon (93.94%), with only 6% emerging in the morning (p < 0.001). The average time period between penetration of the soil by 4th instar larvae and adult emergence was approximately nine months (272 days). Adult population density fluctuations were similar during both years studied here, with the lowest population seen from May to August, a peak in November, and then a decline in population density until March. Path analysis showed that rainfall positively influenced C. psidii population density. The results of this work will be important for the development of sustainable IPM programs aiming to control this serious pest of guava orchards.

番石榴象鼻虫，Conotrachelus psidii马歇尔（鞘翅目：Curculionidae）是番石榴中的主要害虫，关于这种昆虫的生物生态学的信息很少。这项工作旨在通过观察幼虫为了进入土壤化p而放弃果实的时期，不同土壤类型对渗透时间的影响以及随后成虫的出现来验证这种昆虫生命周期某些方面的生物生态学。从土壤。在两年的时间内监测了成年人口水平，并调查了人口密度与气候因素之间的可能关系。在两个时间段（白天和晚上）评估了幼虫对番石榴果实的放弃。观察到第四龄幼虫穿透三种不同土壤类型所花费的时间。将第4龄幼虫释放到装满土壤的盘子后，评估这些昆虫停留在地下的时间以及随后成虫的出现周期。将这些托盘放在野外，每天进行三次观察（上午，中午和下午）。路径分析被用来调查气候变量和成年人口密度之间的关系。四龄幼虫在黏土中的土壤渗透最快，而在沙子中则最慢。没有区别（四龄幼虫在黏土中的土壤渗透最快，而在沙子中则最慢。没有区别（四龄幼虫在黏土中的土壤渗透最快，而在沙子中则最慢。没有区别（p =白天（51％）和夜间（49％）放弃果实的幼虫数量。大部分成年人在白天从土壤中出来（86.84％），与夜间出现的成年人数量（13.16％）有显着差异（p <0.001）。比较一天中不同时段的成年人出没时，大多数在下午出没（93.94％），而早晨则出现6％（p <0.001）。从四龄幼虫进入土壤到成虫出苗的平均时间约为9个月（272天）。在此研究的两个年份中，成年人口的密度波动相似，从五月到八月的人口最低，十一月达到峰值，然后到三月才下降。C. psidii种群密度。这项工作的结果对于制定旨在控制这种番石榴果园严重害虫的可持续IPM计划至关重要。