A comparative analysis on glandular and non-glandular trichomes over leaves and pod surfaces of chickpea (Cicer arietinum L.) genotypes

Abstract

Trichomes in Chickpea serve as a possible defence mechanism against movement and Ovi -positioning of various stages of insect pests. This research was planned to assess the density and length of trichomes on the leaves and pods of forty-two genotypes alongside two local control varieties. Two types of trichomes were identified: non-glandular on leaves and glandular on pods. Only a small number of glandular trichomes were found on leaves, while very few non-glandular trichomes were present on pods. The highest density of non-glandular trichomes on leaves (26.33 trichomes/mm2) was recorded in the chickpea genotype KGG 22016. The lowest count of glandular trichomes on the pods was noted for Genotype KGG 22005 (7.67 glandular trichomes per mm2). In the case of leaves, KGG 22007 (347.23 µm) and KGG 22004 (301.53 µm) exhibited the highest length of non-glandular trichomes, respectively. Conversely, genotypes KGG 22005 (564.97 µm) and KGG 22004 (538.33 µm) showed the greatest glandular trichome length in the pods. The density of non-glandular trichomes on leaves displayed a positive correlation with the number of eggs, the larval survival rate, and the overall larval population, while it had a negative correlation with the percentage of pod damage. On the other hand, the density of glandular trichomes on pods revealed a notable positive correlation with the number of eggs, the H. armigera larval population, larval survival, and pod damage.