R. HERAWATI*, MASDAR and ALNOPRI
Crop Production Department, Faculty of Agriculture, University of Bengkulu, Indonesia
*Corresponding author’s email: reny.herawati70(at)gmail.com, reny.herawati(at)unib.ac.id
Email addresses of coauthors: masdar.msdr(at)gmail.com, alnopri_bkl(at)yahoo.co.id
High production of rice is closely related to high yield component characters namely the number of filled grains per panicle or the density of grains per panicle. These characters are complex and greatly determine yield. These traits are also controlled by many genes whose expression is influenced by environmental conditions. This research aims to study genetic diversity and inheritance patterns of rice yield characteristics in the F4population and to obtain the best genotypes from the selection. The materials in this research were 190 F3 generation seed numbers from the pedigree selection which consisted of 24 field numbers resulting from single crosses between local varieties (Bugis and Sriwijaya) with both IR7858-1 and IR148 (N22) that are tolerant to drought. Our research used an augmented design with four parents as check varieties. The research showed that the grain yield of F4 populations was polygenic and controlled by additive gene actions. The heritability value and coefficient of genetic diversity for grain yield were classified as moderate and high. The intensity of differentials selection by 10 percent based on the grain weight/hill, increased the middle value of other observed characters, like panicle length by 20.9%, the total number of grain by 48.4%, the filled grain number per panicle by 59.7%, and grain weight/hill by 40.9%. However, it decreased percentage of empty grain/panicle by 87.6%. Selection on higher filled grains and dense panicles, regardless of panicle length should be considered for developing the new plant type for upland rice with high yield.
Key words: Grain yield, F4 population, heritability, genetic variability
Key findings: Studying the inheritance systems of characters to form the desired character is an important step in segregating populations. Selection based on high grain yield in the F4 generation is expected to be significant in the development of high yield new type of upland rice.