Participatory Evaluation of Bean Ascochyta Blight [Phoma exigua var. diversispora (Bubak) Boerema] and Constraints of Bean Production in Rwanda

Abstract

Abstract

The awareness and perception of ascochyta blight by farmers is an important factor that affects the type of bean genotype adopted. Although farmers in Rwanda prefer large-seeded bean genotypes, both for consumption and for market, these genotypes are susceptible to ascochyta blight. It has been observed that farmers are abandoning large-seeded bean genotypes, in preference for smaller seeded genotypes, which seem to be more resistant. Therefore, the objective of this study was to assess the awareness and perceptions of bean farmers regarding the influence of ascochyta on the type of bean genotypes being grown. A participatory study was conducted in the districts of Burera and Musanze in northern Rwanda, Kamonyi in southern Rwanda and Rwamagana in eastern Rwanda, during February-November 2014. In addition, the severity and incidence of ascochyta in beans was assessed over two seasons (2014B and 2015A). The study revealed that diseases were the most important bean production constraints. Based on the visual symptoms in the bean fields visited, as a whole, and on the leaves and pods of plants sampled per field, there were more ascochyta infections during Season B than during Season A. The incidence of ascochyta was generally highest in northern Rwanda where, in villages such as Busogo and Rwerere, all the bean fields visited had ascochyta symptoms.Bean growers were able to identify bean ascochyta, but the control measures taken were insignificant, probably due to the lack of knowledge and resources. The disease was associated with excessive rainfall and many other environmental factors, as well as poor crop management practices. Varietal preferences were based on yielding ability, early maturity, marketability, diseases and drought tolerance. Other factors that were considered important, included taste, climbing growth habit, cooking time, large seed size and seed colour. Generally, large-seeded bean varieties were the most preferred in both regions. Farmers that preferred the small-seeded bean genotypes based their preferences on the ability to resist pests and diseases and on their ability to thrive under harsh environments, such as excessive rainfall, drought and mist. However, the large-seeded climbing and red mottled kidney bean genotypes, though susceptible to ascochyta, were the most popular bean varieties grown both for consumption and for sale in the northern and eastern regions, respectively. This therefore, indicated the need to develop bean genotypes that have the qualities of the large-seeded genotypes, but which are resistant or tolerant to, diseases such as ascochyta blight.

Keywords: Bean, production constraints, ascochyta blight, farmers

Cite this Article

Clement Urinzwenimana, Rob Melis, Julia Sibiya. Participatory Evaluation of Bean Ascochyta Blight [Phoma exigua var. diversispora (Bubak) Boerema] and Constraints of Bean Production in Rwanda. Research & Reviews: Journal of Crop Science and Technology. 2017; 6(2): 25–37p.