Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/1/1996
Publication Date: N/A
Technical Abstract: Crop yield is controlled by numerous genetically regulated physiological pathways which interact and respond to given environments in the production of seed. Path coefficient analysis is a method by which key components of yield can be identified and used by breeders as selection criteria. Previous rice studies have used path analyses to study grain yield and yield components (panicle density, panicle weight, grain weight, and numbe of filled grains per panicle). However, in addition to these yield components, several morphological factors (number of nodes of main plant, maximum number of tillers, maximum biomass, biomass at heading, LAI at heading, number of panicle primary branches, and plant height) could be considered to partly influence yield. No literature has been encountered on the path analyses of rice grain yield using both of these types of yield components. The objectives of this study were to develop and interpret information on the nature of interrelationships between various yield components contributing to rice grain yield. Fifteen diverse rice genotypes, selected for being either high or low in their number of tillers, grain size, number of nodes, and panicle size, were used in this study. Two of these genotypes were the cultivars Lemont and Teqing and the rest were near-homozygous progeny from their cross. Field experiments were conducted during 1994 and 1995 at Beaumont, Texas. Plots were thinned to 20 plants per meter-row. Based upon the 2 years of data, panicle weight, number of filled grains per panicle, panicle density, tiller density, number of spikelets per panicle, and kernel weight were components which would positively affect yield. A negative effect was observed for node number. This provides insight to breeders for devising a selection program.