Studies on Stability, Correlation and Path Co-Efficient Analysis for Grain Yield and Component Traits in Amaranth (Published)
Amaranthus hypochondriacus L. is mono-cropped at different plant spacings. Genotype performance varies widely over densities due to variety genetics. It is necessary to identify stable genotypes. Information on genotypes and density will allow for a better evaluation of variety stability. Amaranth genotypes were evaluated for yield characters under very high (D1), high (D2), normal (D3) and low (D4) plant densities to identify stability parameters. The study was conducted at Karaikal, India, during November-February 2007-2008. Genotype Annapurna was stable for grain yield in all plant densities. Genotypes BGA 2, GA 2 and IC 415290 were stable for total carbohydrates and protein content and could be utilized for improvement of these traits. Genotype GA 2 was stable for weight of the inflorescence in all plant densities. Similarly, SKNA 601 was stable for leaf area at 50% flowering in all plant densities. Among characters studied, length of the rachis per inflorescence, total carbohydrates and protein content were relatively stable in all plant densities. These traits are important for selection for improvement at different densities. Results of correlation analysis indicated that weight of the inflorescence, length of the primary inflorescence and number of secondary branches per inflorescence were positively correlated with grain yield and among themselves, indicating that improvement of grain yield in amaranthus could be achieved by selection for these component traits. Path analysis indicated that weight of the inflorescence, leaf area at 50% flowering, length of the primary inflorescence and number of secondary branches per inflorescence had direct positive effects on grain yield. Therefore, the abovesaid traits are important while exercising selection for different density levels.