DETERMINATION OF 18 WHITE CORN HYBRIDS ADAPTABILITY AND STABILITY AMONG CONTRASTING ENVIRONMENT. AZUERO, PANAMÁ. 2002.

Abstract

With the objetive of choosing the experimental corn hybrids with the best stability and adaptability in the country was carried out an experiment throughout 11 contrasting environments in the Azuero Region. The genetic materials of this trial consisted of 18 experimental white hybrids of the IDIAP and PRM. A complete Randomized Block Design with three replications was used; the experimental plots consisted of two rows of 5.2 m of length, separates by 0.8 m. A combined analysis of variance was done and the means was separated by the Least Significant Differences (LSD). To estimate adaptability and stability of hybrids and environments, it was used the Additive Main effects and Multiplicative Interaction (AMMI) and GGE Biplot technique. Agronomic management used regarding to weeds and pest control and fertilization depended of its incidence and the recommendation of IDIAP integral corn management guide. The statistical analysis indicated significant differences (P<0.01) among genotypes, environments and the Genotype-Environment Interaction, indicating the differential response of hybrids in front the different environments. The hybrid group formatted by PB-0105, PRM-1 and PRM-14 outstanding by its high yield and well agronomics characteristics throughout all environments. The GGE_SREG Biplot analysis identified at both first hybrid like to most stables due to present PCA-1 high scores, associated to high yield and PCA-2 low score associated to good stability. By the way, PRM-12 and PRM-2 presented the worst behavior. The model separated the environments in two environmental groups, associated to planting dates. The first environmental group was formed by four localities sowing after September 10 and the other group formed by four localities sowing before this date. The first group presented high yield (6.04 t/ha), and was significative different to other evironmental groups (4.42 t/ha). Due to rainfall scarcity in November and December, the trials planting at the beginning could escape to water stress. El Ejido, Los Castillos and Tablas Abajo presented the same discriminatory canon. In the meantime, Guararé and San Jose were the environments with the best discriminatory canon.