Arachis paraguariensis, a wild peanut species, is a potential experimental system for studying the molecular mechanisms of flowering in the genus Arachis. The present study was carried out to investigate the effect of...Arachis paraguariensis, a wild peanut species, is a potential experimental system for studying the molecular mechanisms of flowering in the genus Arachis. The present study was carried out to investigate the effect of photoperiod on in vitro reproductive behavior of five genotypes of A. paraguariensis. Day-lengths of 12, 16 and 24 h were tested to monitor in vitro flowering using growth chambers kept at 26?C ± 1?C and 60% ± 5% relative humidity under an illumination of 40 μmol?m–2?s–1. Flowering percentage of plantlets ranged from 35% to 93%, 20% to 75%, and 5% to 53% for 12, 16 and 24 h day-lengths, respectively. Genotype PI 262842 displayed the highest frequency of flowering under all the day-length treatments but in vitro flower bud initiation was delayed. The highest mean flowering percentage of 65% across all the genotypes for plantlets exposed to 12 h photoperiod is indicative that flowering induction actually occurred. The results presented in this paper provide evidence for photoperiodic flowering response as well as the occurrence of short day-length-enhanced flowering in A. paraguariensis.展开更多
A quantitative trait locus （QTL） that affects heading date （HD） and the number of spikelets per panicle （SPP） was previously identified in a small region on chromosome 7 in rice （Oryza sativa L.）. In order to ...A quantitative trait locus （QTL） that affects heading date （HD） and the number of spikelets per panicle （SPP） was previously identified in a small region on chromosome 7 in rice （Oryza sativa L.）. In order to further characterize the QTL region, near isogenic lines （NILs） were quickly obtained by self-crossing recombinant inbred line 189, which is heterozygous in the vicinity of the target region. The pleiotropic effects of QTL Ghd7.1 on plant height （PH）, SPP, and HD, were validated using an NIL-F2 population. Ghd7.1 explained 50.2%, 45.3%, and 76.9% of phenotypic variation in PH, SPP, and HD, respectively. Ghd7.1 was precisely mapped to a 357-kb region on the basis of analysis of the progeny of the NIL-F2 population. Day-length treatment confirmed that Ghd7.1 is sensitive to photoperiod, with long days delaying heading up to 12.5 d. Identification of panicle initiation and development for the pair of NILs showed that Ghd7.1 elongated the photoperiod-sensitive phase more than 10 d, but did not change the basic vegetative phase and the reproductive growth phase. These findings indicated that Ghd7.1 regulates SPP by controlling the rate of panicle differentiation rather than the duration of panicle development.展开更多
文摘Arachis paraguariensis, a wild peanut species, is a potential experimental system for studying the molecular mechanisms of flowering in the genus Arachis. The present study was carried out to investigate the effect of photoperiod on in vitro reproductive behavior of five genotypes of A. paraguariensis. Day-lengths of 12, 16 and 24 h were tested to monitor in vitro flowering using growth chambers kept at 26?C ± 1?C and 60% ± 5% relative humidity under an illumination of 40 μmol?m–2?s–1. Flowering percentage of plantlets ranged from 35% to 93%, 20% to 75%, and 5% to 53% for 12, 16 and 24 h day-lengths, respectively. Genotype PI 262842 displayed the highest frequency of flowering under all the day-length treatments but in vitro flower bud initiation was delayed. The highest mean flowering percentage of 65% across all the genotypes for plantlets exposed to 12 h photoperiod is indicative that flowering induction actually occurred. The results presented in this paper provide evidence for photoperiodic flowering response as well as the occurrence of short day-length-enhanced flowering in A. paraguariensis.
基金supported by grants from the National Natural Science Foundation of China(30921091)the National Key Program on Basic Research and Development(2010CB125901)+1 种基金the National Special Program for Research of Transgenic Plants of China(2011ZX08009‐001‐002)the Fundamental Research Funds for the Central Universities(2012YB03)
文摘A quantitative trait locus （QTL） that affects heading date （HD） and the number of spikelets per panicle （SPP） was previously identified in a small region on chromosome 7 in rice （Oryza sativa L.）. In order to further characterize the QTL region, near isogenic lines （NILs） were quickly obtained by self-crossing recombinant inbred line 189, which is heterozygous in the vicinity of the target region. The pleiotropic effects of QTL Ghd7.1 on plant height （PH）, SPP, and HD, were validated using an NIL-F2 population. Ghd7.1 explained 50.2%, 45.3%, and 76.9% of phenotypic variation in PH, SPP, and HD, respectively. Ghd7.1 was precisely mapped to a 357-kb region on the basis of analysis of the progeny of the NIL-F2 population. Day-length treatment confirmed that Ghd7.1 is sensitive to photoperiod, with long days delaying heading up to 12.5 d. Identification of panicle initiation and development for the pair of NILs showed that Ghd7.1 elongated the photoperiod-sensitive phase more than 10 d, but did not change the basic vegetative phase and the reproductive growth phase. These findings indicated that Ghd7.1 regulates SPP by controlling the rate of panicle differentiation rather than the duration of panicle development.
