Study on the effect of phosphorus fertilization and seed dressing fungicide on
occurrence of pea aphid, Acyrthosiphon pisum and yield of lentil was conducted at
Debre Zeit and Chefe Donsa for six consecutive years. Lentil genotypes Alemaya and
ILL-7664 were sown at the rate of 60kg/ha on 2m wide and 4m long plots. Treatments
consisted Apron star 42WS (@ 2.5g per kilogram seed), phosphorus fertilizer (DAP @
100kg/ha), dimethoate (@ 1.8l/ha in spray volume of 200l/ha) as standard check and
untreated control. Pea aphids were sampled by gently beating lentil plants on 20cm by
39cm counting board. The insecticide was applied when the average pea aphid density
was ≥20 per 130cm2. The treatments were combined in factorial combination and
tested in randomized complete block design with four replications. Pea aphid infested
lentil on all treatments at both locations and in all years. Although statistically
nonsignificant, fertilized and seed dressed lentils had greater pea aphid density than
the untreated control. On the other hand, spraying insecticide (dimethoate)
significantly reduced pea aphid density. However, in all years and both locations, the
yield of phosphorus fertilized, seed dressed and insecticide treated lentils were not
statistically different from the untreated control.
