Impact of grasspea genotypes and sowing dates on seed &#946-ODAP concentration and agronomic traits.

Abstract

Grasspea (Lathyrus sativus) is an important food legume crop in Ethiopia. However, its nutritional value ishindered by β-ODAP that causes lathyrism in humans. The extent of toxicity is influenced by genetic andagronomic factors.We conducted an experiment to determine the effect of varieties and sowing dates on the β-ODAP content of the seeds and other yield components. Two varieties, Bio-520 and landrace, were planted onJuly 24, August 7 and 21, and September 4 in the 2001-02 and 2002-03 cropping seasons. Grasspea variety andseason, significantly influenced β-ODAP content of the seeds.The highly significant variety x season interactionssuggests that varieties behave differently in different seasons for their β-ODAP content. The main effects andinteractions were highly significant for days-to-flowering and plant height. Although β-ODAP content of thevarieties varied with season, the improved genotype always contained less β-ODAP concentration.Thus, whilethe development of low-toxin grasspea lines is the primary goal, modifying agronomic practices is also importantto mitigate lathyrism.

Key Words: Ethiopia, Lathyrus sativus, Lathyrism, neurotoxin