This study aimed to investigate the combined effects of nitrogen level （high and ordinary） and high temperature stress （37 ℃, 4 d） at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar con...This study aimed to investigate the combined effects of nitrogen level （high and ordinary） and high temperature stress （37 ℃, 4 d） at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield.展开更多
QTLs for heading date of rice （Oryza sativa L.） with additive, epistatic, and QTL × environment （QE） interaction effects were studied using a mixed-model-based composite interval mapping （MCIM） method and a...QTLs for heading date of rice （Oryza sativa L.） with additive, epistatic, and QTL × environment （QE） interaction effects were studied using a mixed-model-based composite interval mapping （MCIM） method and a double haploid （DH） population derived from IR64/Azucena in two crop seasons. Fourteen QTLs conferring heading date in rice, which were distributed on ten chromosomes except for chromosomes 5 and 9, were detected. Among these QTLs, eight had single-locus effects, five pairs had double-locus interaction effects, and two single-loci and one pair of double-loci showed QTL × environment interaction effects. All predicted values of QTL effects varied from 1.179 days to 2.549 days, with corresponding contribution ratios of 1.04%-4.84%. On the basis of the effects of the QTLs, the total genetic effects on rice heading date for the two parents and the two superior lines were predicted, and the putative reasons for discrepancies between predicted values and observed values, and the genetic potentiality in the DH population for improvement of heading date were discussed. These results are in agreement with previous results for heading date in rice, and the results provide further information, which indicate that both epistasis and QE interaction are important genetic basis for determining heading date in rice.展开更多
USSR5, a japonica rice variety from the former Soviet Union, is an extremely early maturing rice variety. To elucidate the genetic basis for its early heading, genetic analysis was carried out by crossing it with a se...USSR5, a japonica rice variety from the former Soviet Union, is an extremely early maturing rice variety. To elucidate the genetic basis for its early heading, genetic analysis was carried out by crossing it with a set of major gene nearly isogenic lines （NIL） and QTL-isogenic lines. The early heading of USSR5 was attributed to the presence of photoperiod-insensitive alleles at E1 and Se-1 gene, the photoperiod-sensitive inhibitor gene i-Se-1, and the dominant earliness gene Ef-1. Analysis of a backcrossed population （BCIF1） derived from the cross USSR5 x N22 indicated that two quantitative trait loci （QTL） for early heading were located on chromosomes 7 and 8, accounting for 27.4% and 11.2% of the phenotypic variance, respectively, with both early alleles originating from USSRS. From an F2 population of the same cross, early heading QTLs were detected on chromosomes 1, 2, 7, 9, and 10, with individual QTL accounting for between 4.1% and 15.4% of the phenotypic variance. Early heading alleles at four of these five QTLs originated from USSRS. A comparison of chromosomal locations suggests that one of these QTLs may be identical with the known gene Hd4 （E1）. The relationship between the other QTLs and known genes for heading date are not clear. USSR5 is a promising source for propagating earliness for the development of improved early heading rice varieties.展开更多
The seed setting rates of total 198 rice cultivars （lines） at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme na...The seed setting rates of total 198 rice cultivars （lines） at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme natural high temperature on seed setting rate of different rice cultivar （line）. The results showed that the contin- uous high temperature showed certain effects on the seed setting rates of tested materials, and significant differences were shown in seed setting rate among differ- ent rice cultivars （lines）. The seed setting rates differed significantly among indica F1 hybrids derived from different sterile and restorer lines, indicating that the sterile and restorer lines had great effects on heat tolerances of different F~ hybrids. The cor- relation analysis showed that the seed setting rates of conventional indica restorer lines and conventional japonica rice cultivars （lines） were negatively related to the daily highest temperature （P〉0.05）, and the seed setting rates of indica F1 hybrids were positively related to the seed setting rates of their restorer lines. Total four in- dica restorer lines, including Ninghuiguangkangzhan, Shuhui 527, Chenghui 3203 and Xianyin-8, and four new japonica rice cultivars （lines）, including Wuyinjinghui （B2）, Nanjing 4//W3660/Nanjing 44 （B12） and Wuyun 2330/JD6011 （B22） were pre- liminarily screened, and their seed setting rates were all close to the normal level （90%）. The screened rice cultivars （lines） showed higher heat tolerances.展开更多
Using the meteorological data and geographical information during January-March（1961-2010） accumulated by 18 stations of Hainan,a suitability zoning map for thermo-sensitive genetic male sterility（TGMS） rice was m...Using the meteorological data and geographical information during January-March（1961-2010） accumulated by 18 stations of Hainan,a suitability zoning map for thermo-sensitive genetic male sterility（TGMS） rice was made by GIS technology based on temperature indicators required by TGMS rice during fertility sensitive period and heading-flowering period,aiming to provide reasonable layout and scientific basis for sustainable development of TGMS rice in Hainan Island under the background of global warming.The results indicated that the suitable planting zones covered the south regions of Wuzhishan,Jianfengling and Diaoluoshan;subordinate suitable zones expanded northward to central parts of Wuzhishan,Dongfang,Changjiang,Qiongzhong and southern parts of Wanning;the other regions were unsuitable for breeding.展开更多
基金Supported by Special Scientific Research Fund of Meteorological Public Welfare Profession of China(GYHY201406025GYHY201006025)+2 种基金Special Fund for Agroscientific Research in the Public Interest of China(201403002)Young Talent Project of China Meteorological AdministrationJiangxi"555"Ganpo Yingcai Project~~
文摘This study aimed to investigate the combined effects of nitrogen level （high and ordinary） and high temperature stress （37 ℃, 4 d） at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield.
文摘QTLs for heading date of rice （Oryza sativa L.） with additive, epistatic, and QTL × environment （QE） interaction effects were studied using a mixed-model-based composite interval mapping （MCIM） method and a double haploid （DH） population derived from IR64/Azucena in two crop seasons. Fourteen QTLs conferring heading date in rice, which were distributed on ten chromosomes except for chromosomes 5 and 9, were detected. Among these QTLs, eight had single-locus effects, five pairs had double-locus interaction effects, and two single-loci and one pair of double-loci showed QTL × environment interaction effects. All predicted values of QTL effects varied from 1.179 days to 2.549 days, with corresponding contribution ratios of 1.04%-4.84%. On the basis of the effects of the QTLs, the total genetic effects on rice heading date for the two parents and the two superior lines were predicted, and the putative reasons for discrepancies between predicted values and observed values, and the genetic potentiality in the DH population for improvement of heading date were discussed. These results are in agreement with previous results for heading date in rice, and the results provide further information, which indicate that both epistasis and QE interaction are important genetic basis for determining heading date in rice.
基金This work was supported by the National Natural Science Foundation of China (No. 30571142), the 948 Project from the Ministry of Agricultue (No. 2004-Z24), Jiangsu Province High Technology Foundation (No. BG2004303), the Key Technology of Agricultural Structural Adjustment (No. 05-01-05B) and PCSIRT.
文摘USSR5, a japonica rice variety from the former Soviet Union, is an extremely early maturing rice variety. To elucidate the genetic basis for its early heading, genetic analysis was carried out by crossing it with a set of major gene nearly isogenic lines （NIL） and QTL-isogenic lines. The early heading of USSR5 was attributed to the presence of photoperiod-insensitive alleles at E1 and Se-1 gene, the photoperiod-sensitive inhibitor gene i-Se-1, and the dominant earliness gene Ef-1. Analysis of a backcrossed population （BCIF1） derived from the cross USSR5 x N22 indicated that two quantitative trait loci （QTL） for early heading were located on chromosomes 7 and 8, accounting for 27.4% and 11.2% of the phenotypic variance, respectively, with both early alleles originating from USSRS. From an F2 population of the same cross, early heading QTLs were detected on chromosomes 1, 2, 7, 9, and 10, with individual QTL accounting for between 4.1% and 15.4% of the phenotypic variance. Early heading alleles at four of these five QTLs originated from USSRS. A comparison of chromosomal locations suggests that one of these QTLs may be identical with the known gene Hd4 （E1）. The relationship between the other QTLs and known genes for heading date are not clear. USSR5 is a promising source for propagating earliness for the development of improved early heading rice varieties.
基金Supported by National Natural Science Foundation of China(31201181)Earmarked Fund for China Agriculture Research System(CARS-01-47)Project for Breeding and Demonstration of New Super Rice Varieties~~
文摘The seed setting rates of total 198 rice cultivars （lines） at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme natural high temperature on seed setting rate of different rice cultivar （line）. The results showed that the contin- uous high temperature showed certain effects on the seed setting rates of tested materials, and significant differences were shown in seed setting rate among differ- ent rice cultivars （lines）. The seed setting rates differed significantly among indica F1 hybrids derived from different sterile and restorer lines, indicating that the sterile and restorer lines had great effects on heat tolerances of different F~ hybrids. The cor- relation analysis showed that the seed setting rates of conventional indica restorer lines and conventional japonica rice cultivars （lines） were negatively related to the daily highest temperature （P〉0.05）, and the seed setting rates of indica F1 hybrids were positively related to the seed setting rates of their restorer lines. Total four in- dica restorer lines, including Ninghuiguangkangzhan, Shuhui 527, Chenghui 3203 and Xianyin-8, and four new japonica rice cultivars （lines）, including Wuyinjinghui （B2）, Nanjing 4//W3660/Nanjing 44 （B12） and Wuyun 2330/JD6011 （B22） were pre- liminarily screened, and their seed setting rates were all close to the normal level （90%）. The screened rice cultivars （lines） showed higher heat tolerances.
基金Supported by the Project of Meteorological Service Website Construction for HainanBreeding(Qiong Nong Ji Cai No.[2013]18 of Hainan Provincial Department of Agriculture)~~
文摘Using the meteorological data and geographical information during January-March（1961-2010） accumulated by 18 stations of Hainan,a suitability zoning map for thermo-sensitive genetic male sterility（TGMS） rice was made by GIS technology based on temperature indicators required by TGMS rice during fertility sensitive period and heading-flowering period,aiming to provide reasonable layout and scientific basis for sustainable development of TGMS rice in Hainan Island under the background of global warming.The results indicated that the suitable planting zones covered the south regions of Wuzhishan,Jianfengling and Diaoluoshan;subordinate suitable zones expanded northward to central parts of Wuzhishan,Dongfang,Changjiang,Qiongzhong and southern parts of Wanning;the other regions were unsuitable for breeding.
