Adaptability and stability of soybean genotypes inthe state of Mato Grosso, Brazil, and reaction of 111 genotypes to the Asianrust

by Polizel, Analy Castilho

Abstract (Summary)
The major objectives of this study were to evaluate phenotypicaladaptability and stability of soybean genotypes in the state of Mato Grosso, usingdifferent methodologies and to identify soybean genotypes with partial resistanceto Asian rust (Phakopshora pachyrhizi) under artificial inoculation. Phenotypicaladaptability and stability were evaluated in three subsequent years (2003/04,2004/05, 2005/06), two trials, divided into culture cycle (semi-early/ medium andsemi-late/late), in counties of the state of Mato Grosso, using as experimentaldesign randomized blocks, with three repetitions. All genotypes belonged to thebreeding program of UFU. Joint analyses were done with genotype x plantinglocation and genotype x planting location x harvest, and the averages werecompared by the Scott Knott and Tukey tests for subsequent computation ofphenotypical adaptability and stability by seven different methods: multivariatemethod AMMI, reability index; bi-segmented linear regression method; simplelinear regression; deviation of the ideal maximum method, variance componentsmethod, and method of ecovalence. The experiment to evaluate partial resistanceto Phakopsora pachyrhizi was done in Uberlândia-MG, in a green-house, fromDecember 2004 to February 2005 and consisted of three evaluation periods. hefollowing resistance characteristics was evaluated: average latent period (PLM),average number of pustules per leaflet and rust severity. Based on the variablesaverage number of pustules per leaflet and rust severity the area under thedisease progress curve was calculated. Subsequently, analysis of variance wasdone and the averages compared by the Scott Knott test, at 5% probability. Themethodologies studied for phenotypical adaptability and stability were similar andcomplemented each other for the results obtained. The environments differed infavorability as a function of agricultural year. In the early trials, harvest 2003/04,the most productive materials were genotypes UFU 01, Msoy 8400 and Emgopa 316; in 2004/05 was line UFU 19, while in 2005/06 was UFU 13, 18, 22, 23, 24,27, 28, 29, 35, 36 and Msoy 8585. The lines UFU 23 (harvest 2004/05) and UFU24 (harvest 2005/06) presented phenotypicial adaptability and stability in allmethodologies evaluated. As for the semi-late/late cycle trial a greaterperformance was found for line UFU 21 (Confiança x Xingu) in the harvest2004/05 and the materials UFU 18 (FT 50.268-M x Msoy 8400) and 28 (IAC 8-2 xIAC 100), in the harvest 2005/06. Partial resistance to Asian rust was found ingenotypes P 5001 and Coodetec 78. The variables studied can be recommendedfor epidemiology studies of the pathosystem soybean x P. pachyrhizi. Clusteranalysis allowed grouping genotypes with partial resistance to Asian rust.
This document abstract is also available in Portuguese.
Bibliographical Information:

Advisor:Julio Cesar Viglioni Penna; Osvaldo Toshiyuki Hamawaki; Patrícia Guimarães Santos Melo; Antonio Orlando Di Mauro; Fernando César Juliatti

School:Universidade Federal de Uberlândia

School Location:Brazil

Source Type:Master's Thesis

Keywords:genetica soja melhoramento genético


Date of Publication:08/10/2007

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