Department of Plant Science & Crop Protection, University of Nairobi, P.O. Box 29053 - 00625, Nairobi, Kenya.
J Econ Entomol. 2023 Apr 24;116(2):462-471. doi: 10.1093/jee/toac205.
Breeding has significantly improved drought tolerance in green gram but marked yield losses continue due to damage by insect pests. Important pests of green gram are pod borers, Maruca vitrata (F.), aphids, Aphis gossypii Glover and whiteflies, Trialeurodes vaporariorum (Westwood). Management of these pests has partly been constrained by the limited understanding of crop traits that modulate their infestation. Field experiments were conducted in southeastern Kenya to evaluate a collection of old and new green gram varieties for tolerance to field pests, and to identify traits that confer resistance. The old varieties were KS20 and N26, both released in 1990s whereas the modern counterparts were Biashara, Karembo, and Ndengu-Tosha. Results showed significant differences among the varieties in maturity, leaf area, leaf hair density, leaf moisture content, and pod wall thickness. Earliness significantly reduced pest infestation, whereby KS20 matured early while N26 was late, and the new varieties were intermediate. On average, across the three environments, leaf area (R2 ≥ 0.32) and leaf moisture content (R2 ≥ 0.18) positively correlated with pest infestation while leaf hair density (R2 ≥ 0.30), and pod wall thickness (R2 ≥ 0.54) showed a negative association with pod borer and aphid counts. However, results did not reveal any particular traits that associated with the varieties, which implied that breeding of green gram in Kenya has not selected for tolerance to field pests. Nonetheless, green gram field pest management practices could select for varieties with early maturity, open plant canopy, pubescent leaves, and thicker pod walls.
在绿豆中，培育显著提高了其耐旱性，但由于虫害的破坏，仍存在显著的产量损失。绿豆的重要害虫有豆荚螟、Maruca vitrata（F.）、蚜虫、Aphis gossypii Glover 和粉虱、Trialeurodes vaporariorum（Westwood）。这些害虫的管理部分受到对调节其侵染的作物特性的有限理解的限制。在肯尼亚东南部进行了田间试验，以评估一系列旧的和新的绿豆品种对田间害虫的耐受性，并确定赋予抗性的特性。旧品种为 KS20 和 N26，均于 20 世纪 90 年代发布，而现代品种为 Biashara、Karembo 和 Ndengu-Tosha。结果表明，品种之间在成熟度、叶面积、叶毛密度、叶水分含量和豆荚壁厚度方面存在显著差异。早熟显著降低了害虫的侵染，KS20 成熟较早，而 N26 较晚，新的品种则处于中间。平均而言，在三个环境中，叶面积（R2≥0.32）和叶水分含量（R2≥0.18）与害虫侵染呈正相关，而叶毛密度（R2≥0.30）和豆荚壁厚度（R2≥0.54）与豆荚螟和蚜虫计数呈负相关。然而，结果并未揭示任何与品种相关的特定特性，这意味着肯尼亚绿豆的培育并未选择对田间害虫的耐受性。尽管如此，绿豆田间害虫管理实践可以选择具有早熟、开放冠层、有毛叶片和较厚豆荚壁的品种。
