Reducing anti-nutritional factor and enhancing yield with advancing time of planting and zinc application in grasspea in Ethiopia
Grasspea (Lathyrus sativus L.), an important pulse crop in food, feed and for sustainable crop production systems in Ethiopia. Despite its advantage on nutrition and adaptability to harsh climate and low fertile soil, it contains a neurotoxin β – N – Oxalyl α β diamiono propionic acid (β-ODAP) which paralyzes the lower limbs and is affected by genotypic and agronomic factors. The effect of zinc application and planting date on yield and β- ODAP content of two genotypes, experiments were conducted in two regions of Ethiopia.
The main effects of variety, sowing date and zinc and their interactions were significant (P<0.001) for β-ODAP and seed yield, which had linear relationship with zinc. For the improved grasspea variety, an application of 20 kg ha-1 zinc showed a reduction of β-ODAP from 0.15 to 0.088% at Debre Zeit and 0.14 to 0.08% at Sheno and increased its yield from 841 kg ha-1 to 2260 kg ha-1 at Debre Zeit and from 715 to 1835 kg ha-1 Sheno. Early sowing showed a reduction in ODAP content in relation to the late sowing.
An application of Zn beyond even 20 kg ha-1 with an early sowing is recommended for the improved variety.