HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kang, M. S. Articles by Tai, P. Y. P. Search for Related Content PubMed Articles by Kang, M. S. Articles by Tai, P. Y. P. Agricola Articles by Kang, M. S. Articles by Tai, P. Y. P.

Genetic and Phenotypic Path Analyses and Heritability in Sugarcane¹

This study was undertaken to determine phenotypic and genetic correlation coefficients among several agronomic traits in sugarcane (Saccharum spp.) and to analyze their interrelationships through path-coefficient analyses. Other objectives were to determine broad-sense heritability and genetic advance under selection for the traits studied. Random selections from two biparental crosses (‘CP 59-50’ x ‘CP 57-603’ and ‘CP 62-374’ x ‘CP 57-614’) were evaluated in the field for several attributes in plant cane, and first- and second-ratoon crops. Genetic path-coefficient analyses indicated plant height to be less important than stalk diameter and stalk number as a component of cane yield; but at the phenotypic level, all three components were of equal importance. Sucrose (%) had a large direct positive effect on sugar per ton of cane (S/T) whereas Brix (percent soluble solids) had a small negative direct influence on S/T. The S/T component exerted a greater direct effect on tons per hectare of sugar (THS) than did tons per hectare of cane (THC). Broad-sense heritability estimates based plot means for various traits ranged from a low of 77% for THS to a high of 94% for stalk diameter. Expected genetic advance for various traits was reasonably high under selection intensities of 2 to 30%. THC estimated from the weight of a 10-stalk sample per plot was genetically and phenotypically correlated with THC determined by weighing the entire plot (r_s = 0.92, r_p = 0.64) which suggested that a 10-stalk sample per plot would be adequate to determine THC.

Key Words: Path coefficient • Genetic correlation • Phenotypic correlation • Genetic advance • Selection • Variance components • Saccharum spp

² Assistant professor, Univ. of Florida, Inst. of Food and Agric. Sciences, Agric. Res. and Educ. Ctr., Belle Glade, FL 33430, and research geneticists, respectively, U.S. Sugarcane Field Stn., USDA-ARS, Canal Point, FL 33438.

Received for publication January 11, 1982.