REPEATABILITY OF STABILITY PARAMETERS IN HERBACEOUS COTTON

Yield data of seed cotton from 56 experiments of cultivar evaluation w ere evaluated in the Northeast of Brazil, from 1985 to 1992, seeking t o estimate the repeatability of stability parameters. Repeatability es timates for stability index (Pi), linear regression coefficient (beta( 1)) and determination coefficient (R-2) were, most of them, from mediu m to high. The values ranged from 0.45 to 0.67 for the 1985 to 1990 pe riod and 0.45 to 0.96 for 1991 to 1992. These results suggest that sel ection of these traits may give reasonable gains.