Adaptability and stability of tomato genotypes under cultivated in Amazon upland and floodplain soils infested by Ralstonia solanacearum

Abstract

The genetic resistance to Ralstonia solanacearum, the agent of "bacterial wilt" disease, is a condition for tomato cultivation in soils naturally infested by the pathogen in the Amazon upland and floodplain environments. In this work the adaptability and stability of the genetic resistance to pathogen were estimated. Also fruit yield of advanced generation (F13 and F14) progenies from the original crossing (HT-16) of the tomato variety Yoshimatsu under cultivation conditions upland and floodplain in soils naturally infested by R. solanacearum. The experiments were carried out in four environments with soils naturally infested by the pathogen: two in upland and two in the floodplain. The evaluated tomato genotypes were: Santa Cruz Kada, the susceptibility control; Caraíba, the resistant control; C-38; Yoshimatsu 4-11, and four F13 and F14 progenies from the HT-16 crossing. The agronomic traits were evaluated by the parameters: Infection Rate (QR), for disease without multiplication, according PLANK (1963); Index of Sanity (IS), according NODA (1981); Total Yield of Fruits (PTF) and Total Number of Fruits (NTF). Genetic adaptability and phenotypic stability parameters were estimated according to the method proposed by EBERHART and RUSSEL (1966), expressed by genetic resistance to the pathogen R. solanacearum. The data showed that advanced progenies of the HT-16 crossing are adapted for cultivation in upland and floodplain soils infested by the pathogen and demonstrated superiority when compared to F7 variety Yoshimatsu 4-11.