ABSTRACT
Sixty six genotypes of groundnut were used to study the correlation and path analysis for yield and yield contributing characters. Correlation studies revealed that kernel yield was significantly and positively associated with pod yield per plant, number of mature pods per plant, shelling percentage, harvest index, sound mature kernel percentage, specific leaf weight at 60 DAS, protein content and oil content. Path coefficient analysis indicated that pod yield per plant and shelling percentage had high positive direct effect on kernel yield signifying the importance of these traits in the improvement of seed yield.
ABSTRACT
The evaluation of selection criteria using correlation coefficients, multiple regression and path analysis was carried out for a period of two years on sixteen genotypes of rice (Oryza sativa L.).These genotypes were studied during 2008 and 2009 summer seasons at EDduim and Kosti locations in randomized complete block design with three replications per each location. The field experiment is directed to study character association; contribution of various yield influencing traits on rice for establishment of appropriate plant attributes to select and improve the grain yield, and accordingly select the most suitable genotype. Combined analysis of variance revealed highly significant effects of locations, seasons, genotypes and their interactions for most of the studied traits indicating that these genotypes are highly variable. Genotypes differed significantly in grain yield, (NERICA 4, NERICA 14, NERICA 15, YUNLU 33 and WAB-1-38-19-14-P2-HB) were higher yielding genotypes giving 3.78, 4.03, 3.24, 3.55 and 3.51 t/ha respectively. These genotypes presented a valuable source of diversity which can be used for breeding programs. Correlation analysis in both seasons indicated that grain yield was positively and significantly correlated with plant height, number filled grains/ panicle and 1000-grain weight, while it was negatively correlated with percentage of unfilled grains/panicle. Path coefficient analysis indicated that among yield components number of filled grains/ panicle, number of panicles/m2 and 1000-grain weight showed a positive direct effect on grain yield and therefore, may be considered as selection criteria for the improvement of grain yield. Multi-objective decision-making model was employed to rank the studied genotypes according to the measured various yield influencing traits and the degree of association of each trait on yield. For determination of criteria weight this article considers the analysis of correlation that is used frequently in to quantify the degree of association between a response variable, and some explanatory variable. Consequently, we propose new weighted information criteria to be used to guide the selection of the “best” genotype based on determining correlation coefficient. As a result, compromise programming analysis is in agreement with analysis of variance and indicated that genotypes can be ranked in a descending order as: N12, N14, Y30, WAB8, WAB19, N4, Y33, Y26, N15, N17 and Y24.
ABSTRACT
Twenty nine accessions of Orinoco apple (S. sessiliflorum) from the germplasm collection of the Vegetable Breeding Program of the National Research Institute of Amazonia () were evaluated in Northeastern Brazil. The trial was carried out in the Vitória de Santo Antão Experimental Station, of the Pernambuco State Research Enterprise (IPA), Pernambuco. A randomized complete block design, with four replications, was used. The following characters of agronomic importance were evaluated: stem diameter; plant height; leaf area; fruit width; fruit length; locule number; pulp thickness; total fruit number per plant; average fruit weight; total fruit yield; and total soluble solids (Brix). The genotypic correlations among characters were estimated and used in path coefficient analysis to determine their influence on yield. The greatest number of positive and significant correlations occurred with pulp thickness. Total fruit number per plant and pulp thickness were the characters with the greatest direct and positive influence on yield of cubiu.
Vinte e nove populações naturais de cubiu (Solatium sessiliflorum Dunal) da coleção do Programa de Melhoramento Genético de Hortaliças do Instituto Nacional de Pesquisas da Amazônia-INPA, foram avaliadas na região Nordeste do Brasil. O experimento foi conduzido na Estação Experimental da Empresa Pernambucana de Pesquisa Agropecuária-IPA, em Vitória de Santo Antão, Estado de Pernambuco. Adotou-se o delineamento experimental em blocos casualizados com 4 repetições. A unidade experimental foi constituída de uma área de 7,5m2 contendo 5 plantas úteis. Coletaram-se dados referentes ao diâmetro do caule (DC), altura da planta (AP), área da folha (AF), largura do fruto (LF), comprimento do fruto (CF), número de lóculos (NL), espessura da polpa (EP),número total médio de frutos por planta (NMF), peso médio dos frutos (PMF), peso total de frutos (PEF) e teor de sólidos solúveis totais (BRIX). Empregou-se a Analise de Trilha para desdobrar os coeficientes de correlação genotíptea, e observar a inlfuência dos efeitos destes caracteres, na produção de frutos de cubiu. Verificou-se que o maior número de associações positiva e significativa entre os pares de caracteres avaliados ocorreu com a espessura da polpa (EP). A Análise de Trilha desenvolvida sobre os dez caracteres, mostrou que o número total médio de frutos por planta (NMF) e a espessura da polpa (EP) foram os caracteres que mais influenciaram direta e positivamente sobre a produção estimada de frutos de cubiu.