Variation in Thermal time model Parameters Between Two Contrasting Chickpea (<i>Cicer arietinum</i>) cultivars

Abstract

A laboratory experiment was carried out to determine the effect of different constant temperatures on germination and early seedling establishment and to study the variation among parameters of thermal time model parameters for two contrasting chickpea cultivars . Seeds were subjected to six constant temperatures from 10 o C to 35 o C . A complete randomized design was used with four replication. Analysis of variance showed significant differences among treatments for all characters studied. The final germination percentage significantly increased with increasing temperature up to 25 ° C, and thereafter there was a sharp decrease in final germination at 30 ° and 35 ° C. Desi type cultivar (small seeded) “Jabel Marra” significantly exhibited higher final germination percentage and lower germination rate compared with the kabui type cultivar “Shendi” at all temperatures. The median (θ T(50) ) of the thermal time was significantly differ between the two chickpea cultivars. The large seeded cultivars (shendi) recorded significantly higher median thermal time than the small seeded cultivars (Jabel Marra). The results also revealed a significant differences between the two cultivars in all thermal time model parameters. The small seeded cultivar (Jabel Marra) scored lower total dry matter and temperature tolerance index (TTI) compared to the large seeded cultivar (Shendi) at all temperatures studied.