Yield Losses of Fieldpea Due to Ascochyta Blight in Central Ethiopia

Abstract

An experiment was conducted to assess yield losses of field pea (Pisum sativum L.) due to Ascochyta blight mainly caused by Mycosphaerella pinodes (Berk, and Blox) Vestergr at two locations (Holetta and Dendi) during two crop seasons (1996 and
1997) using two cultivars (Local-H and Tegengech). Different blight epidemics were contrived in the experimental plots by employing five spray schedules. At Holetta, mean seed yield was reduced from 0.82 to 0.35 t/ha as final blight score increased from 38 to 89% for the two cultivars in 1996 but it did not drop that low in the 1997 crop season, as the disease pressure was generally low. However at Denbi, disease and yield parameters were comparable in both years. Mean seed yield dropped from 1.68 to 1.3lt/ha as the disease severity increased from 14 to 66% for the two varieties and seasons. In 1996, mean yield losses of 53 and 28% were obtained at Holetta and Denbi, respectively, while in 1997 only 21% were obtained for both locations being the same. The most affected yield components of field pea were pod set and seed size. These levels of yield losses warrant a control measure against this disease.