Genetic improvement of grass pea (Lathyrus sativus) in Ethiopia: an unfulfilled promise

Grass pea (Lathyrus sativus L.) is an important crop in Ethiopia. Its vital importance in the Ethiopian agriculture emanates from its resistance to drought, salinity, waterlogging and low soil fertility. However, low levels of the amino acids methionine and tryptophan and the presence of the neurotoxin beta-N-oxalyl-L-alpha,beta-diaminopropanoic acid (ODAP) in the seeds are the major limitations of the crop. Genetic improvement of grass pea in Ethiopia has been started in the 1960s at Holetta Agricultural Research Center. The major objectives of the grass pea research were to develop and promote high-yielding cultivars with low ODAP content coupled with improved management production packages. However, the 50 years of on-station and on-farm research was not successful in producing outstanding varieties with the desired traits. Compared to other grain legumes, the poor success of varietal development endeavours within the context of grass pea improvement philosophy is typically related to the failure of the conventional breeding approach to fix a zero or low ODAP content because this trait is highly influenced by climatic and edaphic environment.