Rainfall Onset Dates (ROD), Rainfall Cessation Dates (RCD) and Length of rainy Season (LRS) are crucial for Crop production and food security in Eastern Africa yet scantily documented. This paper seeks to investigate the spatial patterns of these parameters. Data used are Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) and National Oceanic and Atmospheric Administration (NOAA) gridded temperature. Threshold of 0.1mm for rainy day, 20mm over 5 days with at least 3 rain days and dry spell not exceeding 7 days in the next 21 days were used to determine RODs, while Potential Evapotranspiration (PET) and Water Balance (WB) criteria were computed to determine RCDs then differences between ROD and RCD were used in calculating LRS. The results showed early rainfall cessation over more than 30 counties in Kenya lead to shortened rainy season by 10–20 days during MAM season. Similarly, 20–40 days early onset dates are observed in most counties in upper Nile, Unity and Jonglei states in South Sudan, while 20–40 days delayed rainfall onset was observed in Khartoum and southern parts of Nile state western Darfur, eastern and Aljazeera states in Sudan, most parts of Ethiopia and Eritrea districts during JJA season. Highlands of western and Nyanza region in Kenya, most parts of Uganda observed rainfall onset by March and no sign of cessation before November. Early cessation over northern Uganda districts was behind shortened LRS, furthermore, the early RODs over western and southwestern Uganda districts increased LRS. Prolonged dry conditions over northern Sudan, southeastern parts of South Sudan, northern Kenya, central Somalia, northern Darfour, Kordofan and northern parts of Sudan exacerbated by significant delayed onset and early cessation of rainfall. These findings are important for rain-fed agricultural planning and food security in the IGAD region of Eastern Africa.
Storage of cassava (Manihot esculenta Cruntz.) planting materials has been a challenge because of its properties of moisture and carbohydrates loss under storage. Two varieties of cassava cuttings 1 m long, stored for four months under four different storage methods in two locations Kabete and Kiboko. The storage methods were clamp under double shade (CUDS), horizontal under shade (HUS), vertical under shade (VUS) and the control horizontal under open ground (HOUG). In each storage method data loggers were installed to record temperature and RH. Percentage carbohydrate, moisture content (MC), 100% dry cuttings (DC) and cuttings dried to 25% or more of its stored length but not 100% were measured at intervals of 4 weeks. Data were subjected ANOVA and means separated using LSD. CUDS performed better than other storage methods in all parameters measured. The results showed cuttings stored under CUDS lost less moisture than those stored in HUOG. The moisture loss in CUDS was from 70.16%-56.69% while that of HUOG dropped from 70.16% to 27.26% within 8 weeks after storage. High rate of carbohydrate loss was observed in Kiboko than Kabete. Mean temperatures were 25 °C Kiboko and 22 °C Kabete. The results showed that temperature had effect on loss of carbohydrate. The results have proven that safe storage of cassava planting material is affected by plant related factors as well as environmental conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.