Germination capacity and seedling vigour of chickpea (Cicer arietinum) seeds damaged either by Adzuki bean beetle (Callosobruchus chinensis) or rice weevil (Sitophilus oryzae)

Stored chickpea is infested by thAdzuki bean beetle and occasionally by the rice weevil, Sitophilus oryzae (L.). However, in Ethiopia, the association between the level of damage done to chickpea seed by each insect species and germination capacity of damaged seeds has not been determined. Thus, a laboratory experiment was conducted in the Seed Laboratory at Debre Zeit Agricultural Research Center using the chickpea cultivars Arerti and Natoli. The seeds that Adzuki bean beetle were damaged were categorized based on the number of holes per seed as 0 = no hole 1 = one hole per seed and so on; whereas seeds that were damaged by rice weevil were classified as either damaged or undamaged. The sand method was followed to test the germination capacity and vigor of the different categories of insect damaged chickpea seeds. All seeds that were damaged by adult rice weevil did not germinate. Moreover, in Adzuki bean beetle damaged seeds, the proportion of normal seedlings, seedling shoot length, seedling root length, seedling fresh weight, seedling dry weight, vigour and speed of germination significantly decreased as the number of holes per seed increased; whereas the proportion of abnormal seedlings and decayed seeds increased as the number of holes per hole increases. Therefore, seed damaged by both Adzuki bean beetle and the rice weevil should not be used as a seed by farmers due to deterioration of seed quality.