以京农科728等18个黄淮海区主推夏播玉米品种为研究材料,设置6月10日(S1)、6月20日(S2)和6月30日(S3)共3个播期处理,研究夏播玉米品种在不同播期条件下的籽粒灌浆特性,以期为玉米品种选择及高产栽培提供参考和指导。结果表明:(1)成熟期...以京农科728等18个黄淮海区主推夏播玉米品种为研究材料,设置6月10日(S1)、6月20日(S2)和6月30日(S3)共3个播期处理,研究夏播玉米品种在不同播期条件下的籽粒灌浆特性,以期为玉米品种选择及高产栽培提供参考和指导。结果表明:(1)成熟期百粒重在不同播期及品种间存在极显著差异,不同播期间表现为S1(35.20 g)>S2(33.45 g)>S3(31.38 g);不同品种间变幅为28.50 g(华美1号)~36.37 g(京农科728)。(2)籽粒平均灌浆速率(Gave)在不同播期条件下表现为S1(0.74 g 100-grain^–1 d^–1)>S2(0.65 g 100-grain^–1 d^–1)>S3(0.57 g 100-grain^–1 d^–1),S1平均灌浆速率分别比S2、S3高0.09和0.17 g 100-grain^–1 d^–1,增幅分别为13.85%和29.82%;18个品种平均灌浆速率以京农科728(0.75 g 100-grain^–1 d^–1)最高,显著高于郑单958和先玉335(0.58 g 100-grain^–1 d^–1和0.67 g 100-grain^–1 d^–1),增幅为29.31%和11.94%。(3)不同播期间参试品种产量表现为S1(10,628.67 kg hm^–2)>S2(10,207.65 kg hm^–2)>S3(9144.59 kg hm^–2),S1分别较S2、S3高4.12%、16.23%;S1与S2下产量相差不大。不同品种间,NK815、MC121、京农科729、MC812、京农科728和先玉335产量相对较高,平均为10,730.56 kg hm^–2,显著高于郑单958(10,080.85 kg hm^–2),增幅为6.44%。(4)相关分析表明,产量与平均灌浆速率(0.70^**)、粒重(0.68^**)呈极显著正相关;与活跃灌浆期(-0.36^**)呈极显著负相关,而粒重与平均灌浆速率(0.58^**)呈极显著正相关。因此,黄淮海区夏播玉米抢时早播有利于获得更高产量,玉米品种可选择种植中熟或中早熟、灌浆速率高、活跃灌浆期适中、产量水平较高的京农科728、京农科729、MC812、MC121、NK815和先玉335等。在播种较晚或积温不足地区,可选择种植中早熟、灌浆速度快的高产型品种京农科728,6月30日播种、10月16日达生理成熟,可实现玉米高产。展开更多
根据自然生态条件及玉米品种的熟期、籽粒灌浆与脱水特性和产量潜力等进行科学品种布局,是实现玉米高产优质和资源高效利用的重要途径。本试验选用中早熟、中熟和中晚熟3个熟期类型,共13个玉米生产主栽品种,通过测定籽粒干物质积累和含...根据自然生态条件及玉米品种的熟期、籽粒灌浆与脱水特性和产量潜力等进行科学品种布局,是实现玉米高产优质和资源高效利用的重要途径。本试验选用中早熟、中熟和中晚熟3个熟期类型,共13个玉米生产主栽品种,通过测定籽粒干物质积累和含水率的动态变化,研究并明确了不同熟期类型玉米品种的籽粒灌浆和脱水特性,旨在为生产品种布局提供参考和指导。试验结果表明:产量、籽粒灌浆和脱水特性在不同熟期类型和品种间均存在显著差异。产量表现为中晚熟(13,813.0 kg hm^–2)>中熟(12,970.4 kg hm^–2)>中早熟品种(10,729.0 kg hm^–2),中晚熟分别较中早熟和中熟品种增产28.7%和6.5%。平均灌浆速率表现为中早熟(0.034 g 100-grain^–1℃^–1)>中熟(0.031g 100-grain^–1℃^–1)>中晚熟品种(0.027 g 100-grain^–1℃^–1),生理成熟后的平均物理脱水速率表现为中熟(0.027%℃^–1 d–1)>中早熟(0.025%℃^–1 d–1)>中晚熟品种(0.018%℃^–1 d–1)。中早熟代表性品种京农科728的平均灌浆速率和生理成熟后的物理脱水速率。分别较3个熟期代表性品种郑单958、先玉335、农华101高38.5%和112.5%、28.6%和54.5%、28.6%和13.3%;中晚熟代表性品种京科968产量潜力最大(14,813.0 kg hm^–2),且平均灌浆速率和物理脱水速率分别较同熟期品种郑单958高7.7%和18.8%。产量与灌浆期天数、积温、平均灌浆速率和百粒重呈显著或极显著正相关,收获期籽粒含水率与灌浆期天数和积温显著正相关、与生理降水速率和物理脱水速率极显著负相关,生理降水速率和物理脱水速率与平均灌浆速率相关性不显著。综上,中早熟、中熟和中晚熟3个不同熟期类型及不同玉米品种的籽粒灌浆和脱水特性差异显著,生产中品种布局除考虑熟期外还需兼顾该特性,以更利于实现玉米高产优质和资源高效利用。展开更多
以京农科728等24个我国生产大面积推广的玉米品种为研究材料,比较不同类型玉米品种的冠层结构、光合及灌浆脱水特性差异,为适宜机收籽粒玉米品种选育和推广提供技术支撑。研究结果表明:(1)参试玉米品种平均机收产量、籽粒含水率、破碎...以京农科728等24个我国生产大面积推广的玉米品种为研究材料,比较不同类型玉米品种的冠层结构、光合及灌浆脱水特性差异,为适宜机收籽粒玉米品种选育和推广提供技术支撑。研究结果表明:(1)参试玉米品种平均机收产量、籽粒含水率、破碎率和杂质率分别为11,658.78 kg hm^(2)、24.66%、3.90%和0.83%。其中,以京2416为父本组配的京农科728等18个适宜机收籽粒玉米品种平均机收产量为11,802.70 kg hm^(2),显著高于郑单958和先玉335,分别增产7.69%和4.45%;收获时籽粒含水率均低于28%(平均为24.61%);破碎率低于5%(平均为3.42%),均达到国家机收籽粒标准。(2)以京2416为父本组配的京农科728等18个宜粒收玉米品种穗上茎叶夹角小,株型紧凑,冠层平均透光率高,冠层光分布更合理。(3)参试品种净光合速率和叶绿素含量平均为34.10μmol CO_(2)m^(-2)s^(-1)和8.91mg m^(2),其中以京2416为父本组配的18个品种净光合速率平均为35.21μmol CO_(2)m^(-2)s^(-1),较郑单958和先玉335高19.60%和6.73%;叶绿素含量平均为9.87 mg m^(2),较郑单958和先玉335高61.54%和68.43%。(4)以京2416为父本组配的18个品种灌浆速率和生理成熟后脱水速率分别平均为0.83 g 100-grain;d^(-1)和0.55%d^(-1),均显著高于郑单958和先玉335,表现为较低的收获时籽粒含水率。(5)相关分析表明,参试玉米品种产量与净光合速率、灌浆速率呈极显著正相关;净光合速率与茎叶夹角呈极显著负相关,与透光率、叶绿素含量呈极显著正相关;收获时籽粒含水率与破碎率、杂质率和生理成熟时籽粒含水率呈极显著正相关,与生理成熟后脱水速率呈极显著负相关,与灌浆速率呈显著负相关。由此可见,以京2416为父本组配的京农科728等18个玉米品种株型紧凑、冠层透光率高、光合能力强、籽粒灌浆和脱水速率高,可实现较低的籽粒含水率和较高的机收籽粒质量。展开更多
Maize landraces White Dent and Golden Queen played a very important role in the pre-hybrid era of maize production in China. However, dozens of accessions with the same names of White Dent and Golden Queen are preserv...Maize landraces White Dent and Golden Queen played a very important role in the pre-hybrid era of maize production in China. However, dozens of accessions with the same names of White Dent and Golden Queen are preserved in China National Genebank (CNG). The present study investigated the genetic diversity of these two important groups of maize landraces, as well as the relationships within and among them. Thirty-four landrace accessions with the name of White Dent and 10 with Golden Queen preserved in CNG were fingerprinted with 52 simple sequence repeats with tailed primer M13. Summary statistics including average number of alleles per locus, gene diversity/expected heterozygosity, and observed heterozygosity were carried out using PowerMarker ver. 3.25 software. The test of Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) of all the 44 maize landrace accessions were also performed by PowerMarker. We observed a significant differentiation in terms of the average number of alleles between White Dent and Golden Queen (6.44 alleles per locus in White Dent, 4.48 in Golden Queen), while both groups of maize landraces had a relatively high but similar gene diversity (0.61 of White Dent, 0.63 of Golden Queen). The fixation index (FST) was only 0.0044, while the percentage of loci deviated from Hardy-Weinberg equilibrium within these two groups of White Dent and Golden Queen was 32.69 and 3.92%, respectively. The rather high genetic diversity and average number of alleles per locus confirmed that both groups of landraces had a rather broad germplasm base. The extremely low fixation index showed that there was little genetic variation between White Dent and Golden Queen and the molecular variation within these two groups was remarkably high, indicating no genetic drift between White Dent and Golden Queen and suggesting different improvement approaches to these two important groups of landraces. Hardy-Weinberg equilibrium test revealed that the group of White Dent was deviated from HWE, whereas Golden Queen was under HWE.展开更多
Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. ...Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha^(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)>fertilizer(11.95%)>hybrids(8.19%)>irrigation(4%) for FP to HH, and hybrids(8.94%)>plant density(4.84%)>fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.展开更多
Drought stress is one of the most important factors limiting maize production. Rab17 is an ABA-responsive gene and associated with drought tolerance. In order to identify haplotypic structure and mine allelic variants...Drought stress is one of the most important factors limiting maize production. Rab17 is an ABA-responsive gene and associated with drought tolerance. In order to identify haplotypic structure and mine allelic variants at tab17 locus, nucleotide diversity and linkage disequilibrium (LD) structure of rab17 were evaluated among a mini core set of Chinese diversified maize inbred lines. Totally, 19 SNP and 18 insertion/deletions (InDels) were identified, among which 81% were in non-coding regions and 19% in coding regions. The results showed that a high level of diversity appeared within 1 kb upstream of the rabl 7 locus, and declined quickly downstream of the gene region. Rapid decay of linkage disequilibrium of rabl 7 region with distance within 1 kb was detected. Functional markers which can be developed based on haplotype 14 are expected to have contribution to molecular breeding for drought tolerance.展开更多
文摘以京农科728等18个黄淮海区主推夏播玉米品种为研究材料,设置6月10日(S1)、6月20日(S2)和6月30日(S3)共3个播期处理,研究夏播玉米品种在不同播期条件下的籽粒灌浆特性,以期为玉米品种选择及高产栽培提供参考和指导。结果表明:(1)成熟期百粒重在不同播期及品种间存在极显著差异,不同播期间表现为S1(35.20 g)>S2(33.45 g)>S3(31.38 g);不同品种间变幅为28.50 g(华美1号)~36.37 g(京农科728)。(2)籽粒平均灌浆速率(Gave)在不同播期条件下表现为S1(0.74 g 100-grain^–1 d^–1)>S2(0.65 g 100-grain^–1 d^–1)>S3(0.57 g 100-grain^–1 d^–1),S1平均灌浆速率分别比S2、S3高0.09和0.17 g 100-grain^–1 d^–1,增幅分别为13.85%和29.82%;18个品种平均灌浆速率以京农科728(0.75 g 100-grain^–1 d^–1)最高,显著高于郑单958和先玉335(0.58 g 100-grain^–1 d^–1和0.67 g 100-grain^–1 d^–1),增幅为29.31%和11.94%。(3)不同播期间参试品种产量表现为S1(10,628.67 kg hm^–2)>S2(10,207.65 kg hm^–2)>S3(9144.59 kg hm^–2),S1分别较S2、S3高4.12%、16.23%;S1与S2下产量相差不大。不同品种间,NK815、MC121、京农科729、MC812、京农科728和先玉335产量相对较高,平均为10,730.56 kg hm^–2,显著高于郑单958(10,080.85 kg hm^–2),增幅为6.44%。(4)相关分析表明,产量与平均灌浆速率(0.70^**)、粒重(0.68^**)呈极显著正相关;与活跃灌浆期(-0.36^**)呈极显著负相关,而粒重与平均灌浆速率(0.58^**)呈极显著正相关。因此,黄淮海区夏播玉米抢时早播有利于获得更高产量,玉米品种可选择种植中熟或中早熟、灌浆速率高、活跃灌浆期适中、产量水平较高的京农科728、京农科729、MC812、MC121、NK815和先玉335等。在播种较晚或积温不足地区,可选择种植中早熟、灌浆速度快的高产型品种京农科728,6月30日播种、10月16日达生理成熟,可实现玉米高产。
文摘根据自然生态条件及玉米品种的熟期、籽粒灌浆与脱水特性和产量潜力等进行科学品种布局,是实现玉米高产优质和资源高效利用的重要途径。本试验选用中早熟、中熟和中晚熟3个熟期类型,共13个玉米生产主栽品种,通过测定籽粒干物质积累和含水率的动态变化,研究并明确了不同熟期类型玉米品种的籽粒灌浆和脱水特性,旨在为生产品种布局提供参考和指导。试验结果表明:产量、籽粒灌浆和脱水特性在不同熟期类型和品种间均存在显著差异。产量表现为中晚熟(13,813.0 kg hm^–2)>中熟(12,970.4 kg hm^–2)>中早熟品种(10,729.0 kg hm^–2),中晚熟分别较中早熟和中熟品种增产28.7%和6.5%。平均灌浆速率表现为中早熟(0.034 g 100-grain^–1℃^–1)>中熟(0.031g 100-grain^–1℃^–1)>中晚熟品种(0.027 g 100-grain^–1℃^–1),生理成熟后的平均物理脱水速率表现为中熟(0.027%℃^–1 d–1)>中早熟(0.025%℃^–1 d–1)>中晚熟品种(0.018%℃^–1 d–1)。中早熟代表性品种京农科728的平均灌浆速率和生理成熟后的物理脱水速率。分别较3个熟期代表性品种郑单958、先玉335、农华101高38.5%和112.5%、28.6%和54.5%、28.6%和13.3%;中晚熟代表性品种京科968产量潜力最大(14,813.0 kg hm^–2),且平均灌浆速率和物理脱水速率分别较同熟期品种郑单958高7.7%和18.8%。产量与灌浆期天数、积温、平均灌浆速率和百粒重呈显著或极显著正相关,收获期籽粒含水率与灌浆期天数和积温显著正相关、与生理降水速率和物理脱水速率极显著负相关,生理降水速率和物理脱水速率与平均灌浆速率相关性不显著。综上,中早熟、中熟和中晚熟3个不同熟期类型及不同玉米品种的籽粒灌浆和脱水特性差异显著,生产中品种布局除考虑熟期外还需兼顾该特性,以更利于实现玉米高产优质和资源高效利用。
文摘以京农科728等24个我国生产大面积推广的玉米品种为研究材料,比较不同类型玉米品种的冠层结构、光合及灌浆脱水特性差异,为适宜机收籽粒玉米品种选育和推广提供技术支撑。研究结果表明:(1)参试玉米品种平均机收产量、籽粒含水率、破碎率和杂质率分别为11,658.78 kg hm^(2)、24.66%、3.90%和0.83%。其中,以京2416为父本组配的京农科728等18个适宜机收籽粒玉米品种平均机收产量为11,802.70 kg hm^(2),显著高于郑单958和先玉335,分别增产7.69%和4.45%;收获时籽粒含水率均低于28%(平均为24.61%);破碎率低于5%(平均为3.42%),均达到国家机收籽粒标准。(2)以京2416为父本组配的京农科728等18个宜粒收玉米品种穗上茎叶夹角小,株型紧凑,冠层平均透光率高,冠层光分布更合理。(3)参试品种净光合速率和叶绿素含量平均为34.10μmol CO_(2)m^(-2)s^(-1)和8.91mg m^(2),其中以京2416为父本组配的18个品种净光合速率平均为35.21μmol CO_(2)m^(-2)s^(-1),较郑单958和先玉335高19.60%和6.73%;叶绿素含量平均为9.87 mg m^(2),较郑单958和先玉335高61.54%和68.43%。(4)以京2416为父本组配的18个品种灌浆速率和生理成熟后脱水速率分别平均为0.83 g 100-grain;d^(-1)和0.55%d^(-1),均显著高于郑单958和先玉335,表现为较低的收获时籽粒含水率。(5)相关分析表明,参试玉米品种产量与净光合速率、灌浆速率呈极显著正相关;净光合速率与茎叶夹角呈极显著负相关,与透光率、叶绿素含量呈极显著正相关;收获时籽粒含水率与破碎率、杂质率和生理成熟时籽粒含水率呈极显著正相关,与生理成熟后脱水速率呈极显著负相关,与灌浆速率呈显著负相关。由此可见,以京2416为父本组配的京农科728等18个玉米品种株型紧凑、冠层透光率高、光合能力强、籽粒灌浆和脱水速率高,可实现较低的籽粒含水率和较高的机收籽粒质量。
基金supported by the Special Program for Crop Germplasm Resources of the Ministry of Agriculture [(NB07-2130135-(25-30)-05]Natural Science Foundation of Beijing (6071003)+1 种基金Innovation Platform Program for Basic Research of Agricultural Breeding in Beijing (YZPT02-06)Scientific and Technological Key Project in Chongqing for Elite Variety Innovation of Rice and Maize (CSTC 2007AB1045)
文摘Maize landraces White Dent and Golden Queen played a very important role in the pre-hybrid era of maize production in China. However, dozens of accessions with the same names of White Dent and Golden Queen are preserved in China National Genebank (CNG). The present study investigated the genetic diversity of these two important groups of maize landraces, as well as the relationships within and among them. Thirty-four landrace accessions with the name of White Dent and 10 with Golden Queen preserved in CNG were fingerprinted with 52 simple sequence repeats with tailed primer M13. Summary statistics including average number of alleles per locus, gene diversity/expected heterozygosity, and observed heterozygosity were carried out using PowerMarker ver. 3.25 software. The test of Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) of all the 44 maize landrace accessions were also performed by PowerMarker. We observed a significant differentiation in terms of the average number of alleles between White Dent and Golden Queen (6.44 alleles per locus in White Dent, 4.48 in Golden Queen), while both groups of maize landraces had a relatively high but similar gene diversity (0.61 of White Dent, 0.63 of Golden Queen). The fixation index (FST) was only 0.0044, while the percentage of loci deviated from Hardy-Weinberg equilibrium within these two groups of White Dent and Golden Queen was 32.69 and 3.92%, respectively. The rather high genetic diversity and average number of alleles per locus confirmed that both groups of landraces had a rather broad germplasm base. The extremely low fixation index showed that there was little genetic variation between White Dent and Golden Queen and the molecular variation within these two groups was remarkably high, indicating no genetic drift between White Dent and Golden Queen and suggesting different improvement approaches to these two important groups of landraces. Hardy-Weinberg equilibrium test revealed that the group of White Dent was deviated from HWE, whereas Golden Queen was under HWE.
基金the National Key Research and Development Program of China(2016YFD0300106)the National Natural Science Foundation of China(31601247)for their financial support。
文摘Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha^(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)>fertilizer(11.95%)>hybrids(8.19%)>irrigation(4%) for FP to HH, and hybrids(8.94%)>plant density(4.84%)>fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.
基金supported by the National Basic Research Program of China (973 Program, 2011CB100105)the National High-Tech R&D Program (863 Program,2006AA10Z188)the National Natural Science Foundation of China (30730063)
文摘Drought stress is one of the most important factors limiting maize production. Rab17 is an ABA-responsive gene and associated with drought tolerance. In order to identify haplotypic structure and mine allelic variants at tab17 locus, nucleotide diversity and linkage disequilibrium (LD) structure of rab17 were evaluated among a mini core set of Chinese diversified maize inbred lines. Totally, 19 SNP and 18 insertion/deletions (InDels) were identified, among which 81% were in non-coding regions and 19% in coding regions. The results showed that a high level of diversity appeared within 1 kb upstream of the rabl 7 locus, and declined quickly downstream of the gene region. Rapid decay of linkage disequilibrium of rabl 7 region with distance within 1 kb was detected. Functional markers which can be developed based on haplotype 14 are expected to have contribution to molecular breeding for drought tolerance.