Facultad de Ciencias Ambientales, Universidad Técnica Estatal de Quevedo, Avenida Quito, Km 1 1/2 vía a Sto. Domingo de los Tsáchilas, Quevedo, Ecuador.
Department of Entomology, Michigan State University, East Lansing, MI.
J Econ Entomol. 2020 Apr 6;113(2):824-831. doi: 10.1093/jee/toz303.
Coptoborus ochromactonus (Smith and Cognato) is one of the most common and important pests of balsa, Ochroma pyramidale (Cav. Ex Lam. Urb.), an economic pillar of the wood industry in Ecuador. Commercial balsa plantations have been expanded from humid to dry climate areas to limit insect damage, but basic knowledge is still lacking on the interaction of C. ochromactonus activity with variation in climate and plantation age. We investigated the effects of climate and host age on the seasonal flight activity of C. ochromactonus and its infestation rate and intensity, as well as the effect of age and individual infestation intensity on balsa dieback. Experiments were conducted in 1-, 2-, and 3-yr-old commercial balsa plantations located in areas of humid or dry climates. Seasonal flight activity (monitored with baited traps) differed between study sites and seasons. Increased flight activity was significantly correlated with higher relative humidity, higher mean temperature, and reduced precipitation during the dry season in the humid site and with increased mean and minimum temperature and increased precipitation during the rainy season in the dry site. Infestation rates by C. ochromactonus significantly increased with plantation age, especially in the humid site. Intensity of individual infestations (measured as number of successful insect entry holes per tree) was significantly influenced by both climate and plantation age, and it was particularly severe on 3-yr-old trees in the dry site. Percentage of foliage loss significantly increased with infestation intensity. Overall, our results can be relevant for devising preventive measures and suitable management strategies for this emerging pest in Ecuadorian wood plantations.
（Smith 和 Cognato）Coptoborus ochromactonus 是轻木（Ochroma pyramidale (Cav. Ex Lam. Urb.)）的最常见和最重要的害虫之一，轻木是厄瓜多尔木材工业的经济支柱。为了限制昆虫的损害，商业轻木种植园已经从潮湿气候地区扩展到干燥气候地区，但对 C.ochromactonus 活动与气候和种植园年龄变化的相互作用的基本了解仍然缺乏。我们调查了气候和寄主年龄对 C.ochromactonus 季节性飞行活动及其侵染率和强度的影响，以及年龄和个体侵染强度对轻木枯萎的影响。实验在位于潮湿或干燥气候地区的 1 年、2 年和 3 年生商业轻木种植园中进行。季节性飞行活动（用诱饵陷阱监测）因研究地点和季节而异。飞行活动增加与相对湿度升高、旱季平均温度升高和降水减少以及雨季平均和最低温度升高和降水增加显著相关。在潮湿地区，C.ochromactonus 的侵染率随种植园年龄的增加而显著增加。个体侵染强度（用每棵树成功进入昆虫的孔数来衡量）受气候和种植园年龄的显著影响，在干燥地区的 3 年生树木上尤其严重。叶片损失百分比随侵染强度的增加而显著增加。总的来说，我们的结果对于制定厄瓜多尔木材种植园这种新出现害虫的预防措施和适当的管理策略可能具有相关性。
