Incidence And Prevalence of Ratoon Stunting Disease (Leifsonia Xyli Subsp. Xyli, Evtushenko) In The Mumias Sugar Cane Growing Zone Kenya

Abstract

Surveys of ratoon stunting disease (RSD) incidence in sugar cane crop (Sacharrum officinurum L) in Mumias were conducted between 2012-2016. Majority of farms constituted seed cane and commercial fields were randomly selected for survey purposes. Samples from 967 farms in four main growing zones including the miller-owned nucleus estate were collected and diagnosed. Multi-stage random sampling method was used to select 967 households, while purposive sampling was used to select commercial fields. The collected data was analyzed using descriptive statistics. Incidence of RSD in the mill supply areas stood at 37%. Disease prevalence was high in N 14 (50%) followed by KEN 83-737 (47%), CO 617 (42%), EAK 73335 (38%), CO 945 and CO 421 each at (37%) and other varieties (27%). There was a positive significant impact on disease occurrence on ratoon crops (p < 0.05). Variety, zone and crop cycle were all significant in influencing the prevalence of RSD. The incidence of RSD was serious in Mumias sugar zone and could be contributing to the low sugarcane yields. Rigorous field hygiene measures such as sterilization of cane knives at harvesting, eradication of volunteer cane and consistent production of healthy seed cane through hot water treatment should be emphasized.