CHARACTERIZATION OF RAINFALL AND TEMPERATURE VARIABILITY AND THEIR IMPACT ON TEFF [Eragrostis tef (Zucc.) Trotter] PRODUCTION AT KERSA DISTRICT OF JIMMA ZONE, ETHIOPIA

Climate variability is affecting the whole world and its threat is greater in Ethiopia because of its less adaptive capacity and deepened poverty.This study was there fore designed to investigate the impact of rainfall and temperature variability on Teff crop performance and quantify their relationship at Kersa district of Jimma zone (1980-2015). Rainfall and temperature data were obtained from National Meteorological Agency(NMA) while Teff yield data collected from Kersa District Agricultural Development Office (KDADO)were used after quality control . The rainfall and temperature data were subjected to analyses of variability indicator indices such as Start of the season(SOS) ,End of the season(EOS) ,Length of growing period(LGP), Length of dry spell probability, Total rainfall, Number of rainy days (NRD), Temperature trend ,correlations and regressions using INSTAT+ V3.37 software and Microsoft Excel Statistical Tool (2013).The analyses of the observed data showed that in Keras district March 17 was identified as the mean start of the Keremt season while November 14 was identified as the mean end date of the Keremt season . The result of rainfall and temperature analysis indicated that at present Kersa district of Jimma zone was facing climate variability such as below normal rainfall associated with drought ,declining trend in NRD,SOS , EOS and LGP while the temperatures were in increasing trends on monthly, Keremt season and annual bases in which annual mean temperature was raising by 0.04 oC annually . Generally Teff production at the study area was significantly influenced positively and negatively by the annual mean temperature and end of the season respectively. To adapt the adverse effects of increasing temperature and variable rainfall, releasing of disease and drought tolerant Teff cultivars are recommended .