Saikai Kanan K, Oduori Celestine, Situma Evans, Njoroge Simon, Murunde Ruth, Kimenju John W, Miano Douglas W, Haukeland Solveig, Coyne Danny
International Institute of Tropical Agriculture (IITA), Nairobi, Kenya.
Agro-Systems Research Group, Wageningen University and Research, Wageningen, Netherlands.
Front Plant Sci. 2023 Jun 20;14:1196171. doi: 10.3389/fpls.2023.1196171. eCollection 2023.
Coffee is an important commodity for Kenya, where production is steadily declining, despite a global rise in demand. Of the various constraints affecting production, plant-parasitic nematodes are a significant, but often overlooked, threat. As a perennial crop, treating plantations once infected with nematodes becomes difficult. The current study evaluated the drenching application of two biocontrol agents, and , for their nematode control efficacy, as well as their impact on the soil nematode community structure on mature, established coffee trees in Kenya. Seven Arabica coffee field trials were conducted over two years on trees of various ages. All the fields were heavily infested with , the first report of the species on coffee in Kenya. Both fungal biocontrol agents were detected endophytically infecting roots and recovered from soil but not until six months after initial applications. The population densities of had significantly declined in roots of treated trees 12 months after the initial application, although soil nematode density data were similar across treatments. Based upon the maturity index and the Shannon index, treatment with led to improved soil health conditions and enrichment of diversity in the microbial community. Application of , in particular, led to an increased abundance of fungivorous nematodes, especially spp., for which would appear to be a preferred food source. The soils in the trials were all stressed and denuded, however, which likely delayed the impact of such treatments or detection of any differences between treatments using indices, such as the functional metabolic footprint, over the period of study. A longer period of study would therefore likely provide a better indication of treatment benefits. The current study positively demonstrates, however, the potential for using biologically based options for the environmentally and climate-smart management of nematode threats in a sustainable manner on established, mature coffee plantations.
咖啡是肯尼亚的一种重要商品，尽管全球需求上升，但该国的咖啡产量却在稳步下降。在影响产量的各种制约因素中，植物寄生线虫是一个重大但常常被忽视的威胁。作为一种多年生作物，一旦种植园感染线虫，进行防治就变得困难。本研究评估了两种生物防治剂的灌根应用对肯尼亚成熟咖啡树的线虫防治效果及其对土壤线虫群落结构的影响。在两年时间里，对不同树龄的咖啡树进行了七次阿拉比卡咖啡田间试验。所有试验田都受到[线虫名称]的严重侵染，这是该线虫在肯尼亚咖啡上的首次报道。两种真菌生物防治剂均被检测到内生感染根系，并能从土壤中回收，但直到初次施用六个月后才出现这种情况。初次施用12个月后，处理过的咖啡树根系中的[线虫名称]种群密度显著下降，不过各处理的土壤线虫密度数据相似。基于成熟度指数和香农指数，[生物防治剂名称1]处理改善了土壤健康状况，并使微生物群落多样性得到丰富。特别是[生物防治剂名称2]的施用导致食真菌线虫数量增加，尤其是[线虫种类]，而[生物防治剂名称2]似乎是其首选食物来源。然而，试验中的土壤均受到压力且贫瘠，这可能延迟了此类处理的效果，或者在研究期间使用诸如功能代谢足迹等指数检测各处理之间的差异。因此，更长时间的研究可能会更好地表明处理的益处。不过，本研究确实积极证明了在已建立的成熟咖啡种植园以可持续方式利用基于生物的方法对环境和气候友好地管理线虫威胁的潜力。
