1 State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China; 2 Institute of Lianyungang Agricultural Science of Xuhuai Area, Lianyungang 222006, China; 3 Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; # These authors contributed equally to this paper; *Corresponding author, E-mail: firstname.lastname@example.org
Abstract Heading dates of 26 japonica rice cultivars native to Southwest China were investigated, and their basic vegetative growth(BVG), photoperiodsensitivities(PS) and temperaturesensitivities(TS) were analyzed under artificially shortday and natural longday conditions in Nanjing of Jiangsu Province, China, as well as artificially high temperature and natural low temperature conditions in winter in Hainan Province, China. The results showed that the PS and TS varied with different cultivars. The BVGs of all the japonica cultivars were well situated, but differed in cultivars. Regression analysis showed a significant correlation between heading date and PS, indicating that PS was the main factor affecting heading date of japonica cultivar in Southwest China. Genetic analyses were conducted on these 26 cultivars using a set of heading date near isogenic lines as tester lines. The results showed that all these japonica cultivars carried the dominant earlyheading gene Ef1 or Ef1t, and most of these cultivars carried the dominant photoperiod sensitivity allele E1 or E1t, the PS of which was slightly weaker than E1. For the Se1 locus, these japonica cultivars mainly carried recessive photoperiod insensitivity gene Se1e. In addition, the recessive allele hd2 could repress or weaken the PS of 22 japonica cultivars by inhibiting the expression of E1 and Se1. These results indicate that the heading date genotypes determined different PS and well situated BVG in japonica rice cultivars of Southwest China. The above results would be useful for breeding and expanding new japonica cultivars with well adaptability in Southwest China.
ZHOU Zhen-ling,#,WEI Xiang-jin et al. Genetic Analysis of Heading Date of Japonica Rice Cultivars in Southwest China[J]. , 2011, 25(3): 267-276 .
Kinoshita T. Report of committee on gene symbolization, nomenclature and linkage groups. Rice Genet Newsl， 1995, 12: 25-25.
Maheswaran M, Mackill D J, Huang N, et al. Identification of RAPD markers linked to Se-3(t)， a gene enhancing the level of photoperiod sensitivity in rice. Rice Genet Newsl， 1995, 12: 219-221.
Ohshima I, Watanabe Y, Asahic C. Genetic analysis of heading time in cross between two indica varieties with two inhibitor genes for photoperiod sensitivity. Jpn J Breed， 1993, 43: 101-106.
Okumoto Y, Tanisaka T, Yamagata H. Heading-time genes of the rice varieties grown in the Tohoku-Hokuriku region in Japan. Jpn J Breed， 1992, 42: 121-135.
Okumoto Y, Tanisaka T. Trisomic analysis of a strong photoperiod-sensitivity gene E1 in rice (Oryza sativa L.). Euphytica， 1997, 95: 301-307.
Yokoo M, Okuno K. Genetic analysis of earliness mutations induced in the rice cultivar Norin 8. Jpn J Breed， 1993, 43: 1-11.
Ichitani K, Okumoto Y, Tanisaka T. Photoperiod sensitivity gene of Se-1 locus found in photoperiod insensitive rice cultivars of the northern limit region of rice cultivation. Breed Sci， 1997, 47: 145-152.
Okumoto Y, Ichitani K, Inoue H. Photoperiod insensitivity gene essential to the varieties grown in the northern limit region of paddy rice (Oryza sativa L.) cultivation. Euphytica， 1996, 92: 63-66.
Ohshima I, Kikuchi F. Identification of a recessive inhibitor for photoperiod-sensitive gene, Se-1， in photoperiod-insensitive varieties of indica type rice//Proceedings of 7th International Congress of SABRAO. Taipei: SABRAO, 1994: 93-100.
Tsai K H. Gene loci and alleles controlling the duration of basic vegetative growth of rice//Rice Genetics. Manila: International Rice Research Institute, 1986: 339-349.
Inoue I, Nishida H, Okumoto Y, et al. Identification of an early heading time gene found in the Taiwanese rice cultivar Taichung 65. Breed Sci， 1998, 48: 103-108.
Yano M, Harushima Y, Nagamura Y, et al. Identification of quantitative trait loci controlling heading date in rice using a high-density linkage map. Theor Appl Genet， 1997, 95: 1025-1032.
Lin S Y, Sasaki T, Yano M. Mapping quantitative trait loci controlling seed dormancy and heading date in rice, Oryza sativa L., using backcross inbred lines. Theor Appl Genet， 1998, 96: 997-1003
Maheswaran M, Huang N, Sreerangasamy S R, et al. Mapping quantitative trait loci associated with days to flowering and photoperiod sensitivity in rice (Oryza sativa L.). Mol Breed， 2000, 6: 145-155.
Yano M, Katayose Y, Ashikari M, et al. Hd1， a major photoperiod sensitivity quantitative trait locus in rice, is closely related to the Arabidopsis flowering line gene CONSTANS. Plant Cell， 2000, 12: 2473-2483.
Takahashi Y, Shomura A, Sasaki T, et al. Hd6， a rice quantitative trait locus involved in photoperiod sensitivity, encodes the α subunit of protein kinase CK2. Proc Natl Acad Sci USA， 2001, 98(14): 7922-7927.
Kojima S, Takahashi Y, Kobayashi Y. Hd3a， a rice ortholog of the Arabidopsis FT gene, promotes transition to flowing downstream of Hd1 under short-day conditions. Plant Cell Physiol， 2002, 43(10): 1096-1105.
Doi K, Izawa T, Fuse T, et al. Ehd1 a B-type response regulator in rice, confers short-day promotion of flowering and controls FT-like gene expression independently of Hd1. Genes Dev， 2004, 118(8): 926-936.
Xue W Y, Xing Y Z, Weng X Y, et al. Natural variation in Ghd7 is an important regulator of heading date and yield potential in rice. Nat Genet， 2008, 40: 761-767.
Wei X J, Jiang L, Xu J F, et al. Genetic analyses of heading date of japonica rice cultivars from Northeast China. Field Crops Res, 2008, 107: 147-154.
Wei X J, Jiang L, Xu J F, et al. Genetic analyses of heading date of japonica rice cultivars in the lower region of the Yangtze River valley. J Integr Plant Biol， 2009, 51(10): 922-932.
Xu J F, Jiang L, Wei X J, et al. Genotypes of heading date of middle indica rice in the mid-lower region of the Yangtze River. J Integr Plant Biol， 2007, 49(12): 1772-1781.
蒋志农． 云南稻作． 昆明： 云南科学技术出版社， 1995.
Yamagata H, Okumoto Y, Tanisaka T. Analysis of genes controlling heading time in Japanese rice//Rice Genetics. Manila: International Rice Research Institute, 1986: 351-359.
Ichitani K, Okumoto Y, Tanisaka T. Genetic analyses of low photoperiod sensitivity of rice cultivars from the northern most regions of Japan. Plant Breed， 1998, 117: 543-547.
Lin H X, Yamamoto T, Sasaki T, et al. Characterization and detection of epistatic interactions of 3 QTLs, Hd-1， Hd-2 and Hd-3， controlling heading date of rice using nearly isogenic lines. Theor Appl Genet, 2000, 101: 1021-1028.
Nishida H, Okumoto Y, Nakagawa H, et al. Analysis of tester lines for rice (Oryza sativa L.) heading-time genes using reciprocal photoperiodic transfer treatments. Ann Bot, 2001, 88: 527-536.
Yokoo M, Kikuchi F. Multiple allelism of the locus controlling heading time of rice, detected using the close linkage with the blast-resistance. Jpn J Breed, 1977, 27: 123-130.
Vergara B S, Chang T T. The Flowering Response of the Rice Plant to Photoperiod: A review of the literature. 4thed. Manila: International Rice Research Institute, 1985: 61.
Okumoto Y, Yoshimura A, Tanisaka T, et al. Analysis of a rice variety Taichung 65 and its isogenic early-heading lines for late-heading genes E1, E2 and E3. Jpn J Breed, 1992, 42: 415-429.