Identification and characterization of the erect-pose panicle gene EP conferring high grain yield in rice (Oryza sativa L.)
- 533 Downloads
The breeding of japonica varieties with erect-pose panicle (EP) has recently progressed in the northern part of China, because these varieties exhibit a far higher grain yield than the varieties with normal-pose panicle (NP). A genetic analysis using the F2 population from the cross between Liaojing5, the first japonica EP variety in China, and the Japanese japonica NP variety Toyonishiki revealed that EP is governed by a single dominant gene EP. Based on previous studies, map-based cloning of EP locus was conducted using Liaojing5, Toyonishiki, their F2 population, and a pair of near-isogenic lines for EP locus (ZF14 and WF14) derived from the cross between the two varieties; consequently, the STS marker H90 was found to completely cosegregate with panicle pose. The H90 is located in the coding sequence AK101247 in the database, and the AK101247 of Liaojing5 has a 12 bp sequence in exon 5 replaced with a 637 bp sequence of its wild type allele. It was therefore considered that the AK101247 encodes the protein of the wild type allele at EP locus, and that the sequence substitution in exon 5 of Liaojing5 is crucial for expression of the EP phenotype. The effects of EP gene on agronomic traits were investigated using two pairs of near-isogenic lines (ZF6 vs. WF6 and ZF14 vs. WF14) derived from the cross between the two varieties. Experimental results showed that EP gene markedly enhanced grain yield, chiefly by increasing number of secondary branches and number of grains on the secondary branch. EP gene also produced a remarkable increase in grain density.
KeywordsWild Type Allele Premature Stop Codon Primary Branch Secondary Branch Rice Breeding
This study was supported in part by a grant from ‘the National Natural Science Foundation of China’ (30871468) and a grant from ‘Youth Foundation of Shenyang Agricultural University’ in China (20070117).
- Chen WF, Xu ZJ, Zhang WZ, Zhang LB, Yang SR (2001) Creation of new plant type and breeding rice for super high yield. Acta Agron Sin 27:665–672Google Scholar
- Futsuhara Y, Kikuchi F (1997) Dwarf characters. In: Matsuo T, Futsuhara Y, Kikuchi F, Yamaguchi H (eds) Science of the rice plant, vol 3. Food and Agriculture Policy Research Center, Tokyo, pp 300–318Google Scholar
- Murai M, Iizawa M (1994) Effects of major genes controlling morphology of panicle in rice. Breed Sci 44:247–255Google Scholar
- Nagao S, Takahashi M (1963) Trial construction of twelve linkage groups in Japanese rice (Genetical studies on rice plant, XXVII). J Fac Agric Hokkaido Univ 53:72–130Google Scholar
- Wang BL, Dong YH, Wang S (1997) Studies on genetic activities of semidwarfism and erect-panicle in rice. J Shenyang Agric Univ 28:83–87Google Scholar
- Xu ZJ, Chen WF, Zhang LB, Zhang CL (1995) The heredity of the erect character and relation with other characters in rice. J Shenyang Agric Univ 26:1–7Google Scholar
- Zhu LH, Gu MH (1979) The inheritance of rice grain shattering. Hereditas 1:17–19 (in Chinese)Google Scholar