Submitted to: Journal of Plant Registrations
Publication Type: Germplasm Registration
Publication Acceptance Date: 2/4/2015
Publication Date: 4/15/2016
Citation: Pinson, S.R., Wang, Y., Tabien, R.E. 2016. Registration of TIL:383.13, TIL:625 and TIL:634, three long grain tropical Japonica Rice (Oryza sativa L.) germplasm lines containing novel Indica Alleles that increase tiller production and grain yield. Journal of Plant Registrations. 10:171-176. Interpretive Summary: An increase in early tiller production is desired in rice to increase yield potential, and enhance ability to shade and suppress weeds. Previous quantitative trait locus (QTL) mapping studies identified nine QTLs for increased tiller number (TN) in rice, with eight QTLs for improved TN coming from the high-tillering indica parental line, ‘TeQing’, and one originating from ‘Lemont’, a tropical japonica rice variety widely commercialized in the US in the 1980’s. Three new rice germplasm lines are being made available to breeders that together possess seven TN alleles of indica rice origin plus one TN QTL of tropical japonica rice origin combined in an elite US tropical japonica rice genetic background with long grain shape and intermediate amylose content and gelatinization temperature. Five to six TeQing TN QTLs were introgressed into each of the three germplasm lines using a backcross breeding program with Lemont as the recurrent parent. Evaluation of these germplasm lines in drill-seeded field trials showed that the increased seedling TN in the three germplasm lines is associated with rapid seedling-stage canopy development, and increased panicle number and grain yield at maturity.
Technical Abstract: These three breeding lines were from a set of 123 progeny lines that were released by the USDA-ARS in 2012 as a mapping population. Chromosomal regions containing genes for increased tiller number under greenhouse conditions were subsequently identified in this population. We used the molecular and greenhouse data to select a subset of progeny lines and observed them under two plant densities in drill-seeded field plots. In this manner, we documented that these three lines, known to contain QTLs affecting TN under greenhouse conditions, did indeed produce more tillers, panicles, and grain yield than the recurrent parent, Lemont, when grown using standard field-production methods.