Effect of selected soil moisture conservation practices on the bean physical quality aflributes and damage caused by the major pests and diseases on Robusta coffee, Coffea canephora (Pierre ex A)

Robusta coffee, Coffea canephora (Pierre ex A) contributes significantly to Uganda’s foreign ex-change and livelihood of its citizen. However, climate variability threatens coffee production and quality by increasing pests and diseases. This study aimed to determine how soil moisture conservation practices affect coffee defects, bean size, and relationship with pests and diseases. This study evaluated the effects of soil moisture conservation practices (SMCPs) on coffee bean defects, bean size, and their relationships with major pests and diseases. The study was con-ducted at the National Coffee Research Institute using an incomplete randomized block design with four SMCPs: coffee under open sun, coffee intercropped with Desmodium intortum, cof-fee mulched with Miscanthidium violaceum, and coffee under Albizia coriaria. Each treatment was replicated three times, and data were collected from four coffee plants per plot. Results showed no significant differences (p ≥ 0.05) in coffee bean defects or screen size distribution across SMCPs. Overall, coffee grown under Albizia coriaria recorded the highest proportion of sound beans (82.31%), while coffee with mulch had the lowest (72.47%). Similarly, coffee bean size did not vary significantly (p ≥ 0.05) among SMCPs. In contrast, pest and disease incidence differed significantly among systems (P ≤ 0.001), except for berries with red blister disease, which showed no significant variation (P = 0.709). Coffee under open sun recorded the highest damage from leaf skeletonizers (10.43%), berry moth (20.11%), brown eye spot (3.48%), and clusters with red blisters (45.36%), whereas coffee with mulch consistently exhibited the lowest pest and disease pressure, except for berry moth (13.49%). Coffee under Albizia cori-aria showed higher incidence of several pests and diseases, including black coffee twig borer (25.64%), leaf miners (11.82%), and berries with red blisters (32.29%), but had the lowest lev-els of berry moth (13.07%) and coffee berry borer (0.37%). In contrast, coffee with cover crop recorded the highest coffee berry borer infestation (3.05%). Overall, the findings indicate that although soil moisture conservation practices did not directly influence coffee bean physical at-tributes, they significantly affected pest and disease incidence, which in turn has implications for coffee quality. The results highlight the importance of integrating soil moisture conser-vation with pest and disease management strategies, with coffee mulching systems showing particular potential for reducing pest pressure and enhancing coffee quality.