Oil palm age and genotype interfere with defoliator lepidopteran infestation

Abstract

The state of Pará has oil palm plantings of different ages and distinct genotypes. The understanding of which factors influence the occurrence and abundance of defoliating caterpillars in palm groves is paramount for control strategies based on integrated pest management (IPM). This study quantified the effect of oil palm age independently, and that of oil palm age and genotype, on the occurrence and abundance of defoliating caterpillars. Data were collected from 1994-2014 and consisted of counting the average number of caterpillars/leaf/parcel. For Opsiphanes invirae and Talima sp., leaf 17 was sampled; for Acharia spp., Euclea sp., Euprosterna elaeasa, Natada sp., and Automeris liberia, leaf 25 was sampled. For Oiketicus kirbyi, Antaeotricha sp., and Brassolis sophorae no specific leaf was considered. Palm trees were classified into three groups: young palm trees (0-8 years after planting), adult palm trees (9-19 years after planting), and old palm trees (over 20 years after planting). Talima sp. showed the highest population peak followed by O. invirae, Acharia spp., Elaeis elaeasa and Euclea sp. This study concludes that genotype has an impact on the infestation by defoliating caterpillars. Also, oil palms at reproductive age are more prone to higher infestation levels than young trees. While population levels of defoliating caterpillars are low in general, outbreaks are frequent. Importantly, intraspecific genotypes are more vulnerable than interspecific genotypes to infestations by defoliating caterpillars. This study contributes to the bioecological knowledge on defoliating caterpillars on oil palm and therefore provides important information to strengthen integrated pest management practices.

Higher avian biodiversity, increased shrub cover and proximity to continuous forest may reduce pest insect crop loss in small‐scale oil palm farming

“…Such results may suggest that mature palms tend to be more vulnerable to herbivorous pests compared with younger palms. Indeed, oil palm stand age has been known to shape local biodiversity communities, including those of vertebrate and insect pests (Oliveira et al., 2021; Sahari et al., 2019; Wood & Fee, 2003). More mature palms may provide more pest resources (such as fruits and foliage), attracting more herbivorous pests.…”

Global Advances on Insect Pest Management Research in Oil Palm

“…de Oliveira et al [7] reported that oil palm genotypes influenced its susceptibility to defoliators, with interspecific crosses between oil palm and its close relative Elaeis oleifera (Kunth) such as genotype Deli × Lamé being more susceptible to the leaf-eaters compared to crosses involving different varieties of oil palm. The high susceptibility of the genotype Deli × Lamé was of great concern as the variety is popularly grown worldwide due to its high yields.…”

“…Although peak palm oil yields of 12 t ha −1 yr −1 have been achieved in small plantations against a theoretically simulated yield potential of 18.5 t ha −1 yr −1 , average oil palm productivity worldwide has stagnated around 3 t ha −1 yr −1 [6]. The suboptimal oil palm productivity is attributed to climatic factors such as rainfall and temperature, nutrient deficiency (especially potassium and nitrogen), unsuitable ground vegetation, soil characteristics (e.g., depth and structure), genotypes, pests and diseases, among other factors [6,7]. The intensive monoculture of oil palm makes it highly susceptible to a range of indigenous insect pests due to reduced crop biodiversity which supports natural enemies of the pests [7][8][9][10].…”

“…The suboptimal oil palm productivity is attributed to climatic factors such as rainfall and temperature, nutrient deficiency (especially potassium and nitrogen), unsuitable ground vegetation, soil characteristics (e.g., depth and structure), genotypes, pests and diseases, among other factors [6,7]. The intensive monoculture of oil palm makes it highly susceptible to a range of indigenous insect pests due to reduced crop biodiversity which supports natural enemies of the pests [7][8][9][10]. In this study, we review research advances in the management of key insect pests of oil palm globally, highlighting new research directions towards more effective management of the pests for improved oil palm productivity.…”