Assessment of Oil Palm Pollinating Weevil (Elaeidobius kamerunicus) Population Density in Biparental dura × pisifera Hybrids on Deep Peat-Soil in Perak State, Malaysia

Abstract

This study was conducted to assess the Elaeidobius kamerunicus (EK) population density among the biparental dura × pisifera hybrids’ palms on deep peat-soil. Twenty-four hybrids derived from 10 genetic sources were used. Variance analysis showed that the EK population density varies between different oil palm hybrids, with a more noticeable variation of a low population mean in the male weevil across the hybrids. The highest weevil population mean/spikelet was attained on the third day of anthesis. The maximum monthly population of EK/spikelet (12.81 ± 0.23) and population density of EK (1846.49 ± 60.69) were recorded in January. Accordingly, 41.67% of the hybrids recorded an EK population density greater than the trial means of 973.68 weevils. Hybrid ECPHP550 had the highest mean of EK/spikelet (10.25 ± 0.11) and the highest population density of EK/palm (1241.39 ± 73.74). The parental mean population was 963.24 weevils and parent Deli-Banting × AVROS recorded the highest EK population density (1173.01). The overall results showed a notable disparity in the EK population among the biparental hybrids. Parental Deli-Banting × AVROS and hybrid ECPHP550 could be more useful to optimize the weevil population for pollination improvements in palm plantations. However, we suggest that volatile production should be included as a desirable trait in oil palm selective breeding.

Bunch component performance of AVROS and Yangambi population

“…The F/B value is closely related to the fruit set of bunches. The fruit set value is influenced by several extrinsic factors, such as water [14], nutrition ,and pollination/pollinator [20,21]. Genetically, the F/B value has a low heritability value based on SNP and SSR marker tests compared to ODM and S/F values [22].…”

Oil Palm Inflorescence Sex Ratio and Fruit Set Assessment in dura × pisifera Biparental Progenies on Fibric Peat Soil

“…In yield improvement of oil palm in any selection and breeding program, fresh fruit bunch and oil yield are the primary motives. However, fruit set that enhances yield improvement of both fresh fruit bunch and oil yield is greatly influenced by parthenocarpic fruit (PCF), with a series of contributing factors such as planting materials, pollinating weevils, the ratio of sex inflorescence, as well as environmental factors [12,13]. In plant breeding, for rapid advancement to take place, a substantial amount of heritability and variation should provide adequate scope intended for a rejoinder to selection in the characters selected [28].…”

“…The progenies used in this present study were planted on a fibric peat soil by MPOB in September 2008 as trial 0.502 in Teluk-Intan research station, Bagan-Datuk. The peat soil was formed through fibric organic materials and it was equitably homogeneous and flat, exposed to a moderate distribution of rainfall [12,13]. The experimental environment had a relative humidity of about 85%, an average field temperature of 27 • C, with 32 • C maximum and 21 • C minimum, with around 2100 mm of total yearly rainfall [12].…”

Factors Affecting Pollination and Pollinators in Oil Palm Plantations: A Review with an Emphasis on the Elaeidobius kamerunicus Weevil (Coleoptera: Curculionidae)

“…Predators, such as insectivorous rodents, birds, insects in the orders of Heteroptera, Hymenoptera, and Diptera, and spiders, can significantly influence the population dynamics of E. kamerunicus and affect their pollination behavior [ 13 , 52 , 76 , 77 ]. Omnivorous rodents, such as Rattus tiomanicus and Rattus tanezumi , feed on a variety of food sources, including E. kamerunicus , and can reduce weevil populations through predation.…”

“…For example, research has shown that black-throated Prinia in Indonesian oil palm ecosystems primarily feed on E. kamerunicus , which constitutes more than 75% of their diet. These birds specifically target male inflorescences during anthesis, making them vulnerable, as reported by [ 76 ]. However, the impact of these predators on E. kamerunicus populations and their pollination activity is not fully understood, and more research is needed to clarify their significance [ 27 ].…”