Karimi Joseph M, Nyaanga Jane G, Mulwa Richard M S, Ogendo Joshua O, Bett Philip K, Cheruiyot Erick K, Arnold Sarah E J, Belmain Steven R, Stevenson Philip C
Department of Crops, Horticulture and Soils, Egerton University, Egerton, Kenya.
Department of Biological Sciences, Egerton University, Egerton, Kenya.
Front Insect Sci. 2024 Jun 28;4:1328235. doi: 10.3389/finsc.2024.1328235. eCollection 2024.
Lablab ( L.) is an important food and livestock feed legume that can also enhance soil fertility. However, its production is limited by insect pests, notably the black bean aphid (). The present field study was conducted to determine the difference in the contribution of lablab genotypes and natural field margin vegetation (FMV) to the abundance and diversity of natural enemies and the damage, incidence, and abundance of bean aphids. Eighteen lablab genotypes were planted in the presence or absence of FMV in a randomized complete block design experiment replicated four times. Data on aphid abundance, incidence, and severity of damage were collected at four growth stages of the crop. Lablab genotypes significantly influenced aphid incidence, suggesting some level of tolerance to aphid colonization. Findings showed that lablab genotypes were a significant influence on natural enemy species richness with no statistical difference for abundance and natural enemy species diversity. However, the genotypes did not vary significantly in their influence on the number of aphid natural enemies. FMV was associated with low bean aphid damage. Overall, the presence or absence of FMV did not influence the number of natural enemies caught on the crop. This concurs with recent work that shows a similar number of natural enemies with field margin plants but may reflect the reduced number of pest insects. Cropping seasons influenced aphid abundance and damage severity, with the populations developing at the early stages of lablab development and decreasing as the crop advanced. This pattern was similar both in the presence or absence of FMV. The findings of this study highlight the important contribution of crop genotype together with the presence of field margin species in the regulation of aphids and their natural enemies in lablab.
豆科扁豆属植物是一种重要的食用和家畜饲料豆类，还能提高土壤肥力。然而，其产量受到害虫的限制，尤其是黑豆蚜。本田间研究旨在确定扁豆基因型和天然田边植被对天敌数量和多样性以及豆蚜危害、发生率和数量的贡献差异。在有或没有田边植被的情况下，以随机完全区组设计进行实验，种植了18种扁豆基因型，重复4次。在作物的四个生长阶段收集了蚜虫数量、发生率和危害严重程度的数据。扁豆基因型对蚜虫发生率有显著影响，表明对蚜虫定殖有一定程度的耐受性。研究结果表明，扁豆基因型对天敌物种丰富度有显著影响，而在天敌数量和天敌物种多样性方面无统计学差异。然而，不同基因型对蚜虫天敌数量的影响没有显著差异。田边植被与较低的豆蚜危害相关。总体而言，田边植被的有无不影响在作物上捕获的天敌数量。这与最近的研究结果一致，即田边植物上的天敌数量相似，但可能反映了害虫数量的减少。种植季节影响蚜虫数量和危害严重程度，蚜虫种群在扁豆生长早期出现，并随着作物生长而减少。无论有无田边植被，这种模式都是相似的。本研究结果突出了作物基因型以及田边物种在调节扁豆蚜虫及其天敌方面的重要贡献。
