The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Pro...The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Progressive pruning is an oil palm pruning method in which pruning is done at the same time as fresh fruit bunch harvesting. This study evaluated the impact of progressive pruning on leaf miner population in oil palm and how these two factors (leaf miner and progressive pruning) affect the yield of oil palm at the Benso Oil Palm Plantation Public listed company (BOPP. Plc). Five distinct blocks in the plantation were selected for observations on fronds at various ranks (33, 25, or 17) based on the degree of defoliation by counting the number of pests on leaflets at different phases of insect development. Fronds from selected plots were sampled in a Completely Randomized Design (CRD). The size of plots used for the study ranged between 19 to 45 hectares. A minimum of 78 fronds were evenly cut from each block for pest count depending on the block size. Secondary data on annual yields of fresh fruit bunches before and after the introduction of progressive pruning were also obtained from BOPP. Plc records from 2011-2020. The results from the analyzed data on leaf miner index before and after the introduction of progressive pruning showed that progressive pruning has, to a high extent (64% to 36%), reduced leaf miner populations in the plantation. Paired t-test on fresh fruit bunch yield has also revealed a significant (p < 0.001) increase in annual fresh fruit bunch yield due to progressive pruning. A regression analysis, however, revealed a lower rate of yield loss (3.05 to 2.70 tonnes) to leaf miner infestation after the introduction of progressive pruning. The study recommends progressive pruning as a key cultural practice for improving crop yields in leaf miner prone plantations.展开更多
Preferences of different oil palm crosses in the station of Pobè in Benin were tested on Coelaenomenodera lameensis by monitoring the natural population for 7 consecutive years. Experiments monitoring of developm...Preferences of different oil palm crosses in the station of Pobè in Benin were tested on Coelaenomenodera lameensis by monitoring the natural population for 7 consecutive years. Experiments monitoring of developmental stages of the insect were performed on material types Elaeis guineensis and Elaeis oleifera. Observations were performed every two weeks on leaves of different ranks (25, 17 or 9) depending on the degree of defoliation by counting the different stages of insect development on leaflets. The results showed that the evolution of pest density is a function of species and the origin of the materials being compared. Population densities of different stages of C. lameensis were more abundant in the crosses from Yocoboué where average population indices were higher at all stages of development from early observations. By contrast, in crosses La Mé, Yangambi and Deli, the numbers of larvae, pupae and adults were lower. Among these three crosses infestation was more abundant in La Mé, followed by Yangambi and Deli. E. oleifera is much less or not attacked. The stages of development (larvae and adults) were also differently held in oil palm origins in comparison. The larval population is significantly important during the short rainy season and lesser important during the dry season. These results may contribute to the development of suitable materials for the genetic improvement of breeding tolerant oil palm material to leaf miner.展开更多
文摘The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Progressive pruning is an oil palm pruning method in which pruning is done at the same time as fresh fruit bunch harvesting. This study evaluated the impact of progressive pruning on leaf miner population in oil palm and how these two factors (leaf miner and progressive pruning) affect the yield of oil palm at the Benso Oil Palm Plantation Public listed company (BOPP. Plc). Five distinct blocks in the plantation were selected for observations on fronds at various ranks (33, 25, or 17) based on the degree of defoliation by counting the number of pests on leaflets at different phases of insect development. Fronds from selected plots were sampled in a Completely Randomized Design (CRD). The size of plots used for the study ranged between 19 to 45 hectares. A minimum of 78 fronds were evenly cut from each block for pest count depending on the block size. Secondary data on annual yields of fresh fruit bunches before and after the introduction of progressive pruning were also obtained from BOPP. Plc records from 2011-2020. The results from the analyzed data on leaf miner index before and after the introduction of progressive pruning showed that progressive pruning has, to a high extent (64% to 36%), reduced leaf miner populations in the plantation. Paired t-test on fresh fruit bunch yield has also revealed a significant (p < 0.001) increase in annual fresh fruit bunch yield due to progressive pruning. A regression analysis, however, revealed a lower rate of yield loss (3.05 to 2.70 tonnes) to leaf miner infestation after the introduction of progressive pruning. The study recommends progressive pruning as a key cultural practice for improving crop yields in leaf miner prone plantations.
文摘Preferences of different oil palm crosses in the station of Pobè in Benin were tested on Coelaenomenodera lameensis by monitoring the natural population for 7 consecutive years. Experiments monitoring of developmental stages of the insect were performed on material types Elaeis guineensis and Elaeis oleifera. Observations were performed every two weeks on leaves of different ranks (25, 17 or 9) depending on the degree of defoliation by counting the different stages of insect development on leaflets. The results showed that the evolution of pest density is a function of species and the origin of the materials being compared. Population densities of different stages of C. lameensis were more abundant in the crosses from Yocoboué where average population indices were higher at all stages of development from early observations. By contrast, in crosses La Mé, Yangambi and Deli, the numbers of larvae, pupae and adults were lower. Among these three crosses infestation was more abundant in La Mé, followed by Yangambi and Deli. E. oleifera is much less or not attacked. The stages of development (larvae and adults) were also differently held in oil palm origins in comparison. The larval population is significantly important during the short rainy season and lesser important during the dry season. These results may contribute to the development of suitable materials for the genetic improvement of breeding tolerant oil palm material to leaf miner.