Disease Tolerance Levels and Growth Potential of Selected Brachiaria Cultivars in Selected Agro-Ecological Zones of Western Region, Kenya

Abstract

Brachiaria is a newly introduced forage grass in Kenya and other countries that has potential for improving livestock productivity but there is limited availability of seed this has become a major constraint. Pastures in western Kenya faces both pathological and physiological problems associated with both biotic and abiotic factors that leads to poor livestock production especially in the dairy industry. This research study focused on evaluating disease tolerance and growth potential of selected Brachiaria cultivars Xaraes (Xaraes palisade), Piata (Piatã palisade), MG4 in the selected agro-ecological zones of Western Region, Kenya. Mulato II grass was included as a control. The experiment was replicated three times at two different agro-ecological zones namely KALRO Kakamega LM2 and KALRO Alupe, Busia LM1 agro ecological zones therefore this study was a 2×3×5 factorial laid in a split plot. Root splits used as planting material were sourced from KALRO Kakamega farm. Phosphate fertilizer at the rate 40 kg/ha P2O5 were used at planting and the crop was top dressed with Nitrogen fertilizer at the rate 100 kg/ha N.  Data collected included number of tillers, plant height at different stages, light interception, leaf area index and diseases incidence on the seeds. In LM1 Mulatto II had the highest height and Basilisks had the lowest height and vice versa for LM2. In both agro-ecological zones Basilisks had the highest number of tillers. In terms of disease establishment, in LM2 (KALRO-Kakamega); Basilisks was the most affected cultivar by both false smut and ergot diseases at 58% and 69.33% incidences respectively. MG4 had the least ergot incidence at 41%, while Xaraes had the least incidence for false smut at 32%. In LM 1 (Alupe Busia), no cultivar exhibited disease. Most cultivars intercepted light higher in LM2 and lower in LM1. Mulatto II and Xaraes had the highest and lowest light interception respectively in LM1 (Alupe Busia), while Basilisks and Xaraes had the highest and lowest interceptions respectively in LM2 (KALRO-Kakamega). The trends were the same in terms of LAI though MG4 had the lowest LAI in LM1. Through this study Basilisks, Xaraes, Mulatto II and Piata were moderately tolerant to ergot disease while MG4 was highly tolerant. Basilisks and MG4 were moderately tolerant to false smut disease while Xaraes had high tolerance levels This research serves as a baseline for future research on Brachiaria forage yield and provide knowledge-based information on production of high quality Brachiaria seeds with the view of enhancing their availability scaling-up Brachiaria forage production to enhance dairy productivity in smallholder farm.