The efficacies of biological and conventional chemical insecticides against two major insect pests of alfalfa(aphids and thrips)were compared in three sites across China’s alfalfa belt.In addition,the persistence of ...The efficacies of biological and conventional chemical insecticides against two major insect pests of alfalfa(aphids and thrips)were compared in three sites across China’s alfalfa belt.In addition,the persistence of the residues of chemical insecticides in alfalfa and their influence on the quality of alfalfa hay were examined.Efficacy varied among the different biological and chemical insecticides.The chemical insecticides were significantly more effective than biopesticides in a short time-frame.The efficacy period of biopesticides was significantly longer than that of chemical insecticides,and the corrected mortality rate of aphids in all regions was above 50%at 14 days after application.The analysis of pesticide residues showed that the residual doses of all the pesticides were within the allowed ranges after the safe period.The acid detergent fiber and neutral detergent fiber contents in alfalfa hay were higher and the protein content was lower in chemical insecticide treatments than in biopesticide treatments in Hebei.The relative feeding value of alfalfa hay treated with Metarhizium anisopliae IPP330189 was the highest among the treatments.Compared with chemical insecticides,the yield of alfalfa hay was higher in the biopesticides treatments.Biopesticides show a stronger control effect on insect populations and also a better improvement in the quality of alfalfa hay than chemical insecticides.This study provides a basis for exploring and developing a comprehensive control regime for alfalfa insect pests in the different alfalfa-growing regions in China,and for reducing chemical insecticide usage and improving forage quality.展开更多
Planting under plastic-film mulches is widely used in spring maize production in arid-cold regions for water conservation and warming the soil.To ameliorate the associated issues such as plastic-film residues and addi...Planting under plastic-film mulches is widely used in spring maize production in arid-cold regions for water conservation and warming the soil.To ameliorate the associated issues such as plastic-film residues and additional labor during the“seedling release”in spring maize production,we have developed a plastic-film-side seeding(PSS)technology with the supporting machinery.In the semi-arid regions of Northwest China,a 7-year trial demonstrated that PSS increased plant number per hectare by 6547 and maize yield by 1686 kg ha–1compared with the traditional method of seeding under plastic-film mulch(PM).Two-year experiments were conducted in two semi-arid regions to further understand the effects of PSS on three important aspects of production:(i)the moisture and temperature of soil,(ii)maize development,yield output,and water use efficiency(WUE),and(iii)the revenue and plastic-film residuals in comparison with that of flat planting(CK)and PM.Continuous monitoring of the soil status demonstrated that,compared with CK,the PSS treatment significantly increased the temperature and moisture of the 0–20 cm soil in the seeding row at the early stage of maize development,and it also promoted grain yield(at 884–1089 kg ha^(–1))and WUE,achieving a similar effect as the PM treatment.Economically,the labor inputs of PSS were equal to CK,whereas the PM cost an additional 960 CNY ha–1in labor for releasing the seedlings from below the film.Overall,the PSS system increased profits by 5.83%(547 CNY ha^(–1)yr^(–1))and 8.16%(748 CNY ha^(–1)yr^(–1))compared with CK and PM,respectively.Environmentally,PSS achieved a residual film recovery rate of nearly 100%and eliminated 96 to 130 kg ha^(–1)of residual plastic-film in PM in 3–5 years of maize production.Collectively,these results show that PSS is an eco-friendly technique for improving yield stability and incomes for the sustainable production of maize in semi-arid regions.展开更多
Nitrogen(N) and seeding rates are important factors affecting grain yield and N use efficiency(NUE) in directseeded rice. However, these factors have not been adequately investigated on direct-seeded and double-season...Nitrogen(N) and seeding rates are important factors affecting grain yield and N use efficiency(NUE) in directseeded rice. However, these factors have not been adequately investigated on direct-seeded and double-season rice(DDR) in Central China. The objective of this study was to evaluate the effects of various N and seeding rates on the grain yield and NUE of an ultrashort-duration variety grown under DDR. Field experiments were conducted in 2018 in Wuxue County and 2019 in Qichun County, Hubei Province, China with four N rates and three seeding rates.The results showed that the grain yield of the ultrashort-duration variety ranged from 6.32 to 8.23 t ha–1with a total growth duration of 85 to 97 days across all treatments with N application. Grain yield was increased significantly by N application in most cases, but seeding rate had an inconsistent effect on grain yield. Furthermore, the response of grain yield to the N rates was much higher than the response to seeding rates. The moderate N rates of 100–150 and 70–120 kg N ha–1in the early and late seasons, respectively, could fully express the yield potential of the ultrashort-duration variety grown under DDR. Remarkably higher N responses and agronomic NUE levels were achieved in the early-season rice compared with the late-season rice due to the difference in indigenous soil N supply capacity(INS) between the two seasons. Seasonal differences in INS and N response should be considered when crop management practices are optimized for achieving high grain yield and NUE in ultrashort-duration variety grown under DDR.展开更多
Background Direct seeding is potentially a more cost-effective alternative to conventional tree planting for restoring tropical forest ecosystems.However,seed loss,due to removal and damage by animals,can substantiall...Background Direct seeding is potentially a more cost-effective alternative to conventional tree planting for restoring tropical forest ecosystems.However,seed loss,due to removal and damage by animals,can substantially reduce seedling establishment.Therefore,this study examined the impact of seed predation on seedling establishment of five tree species,native to upland evergreen forests of northern Thailand:Hovenia dulcis,Alangium kurzii,Prunus cerasoides,Choerospondias axillaris and Horsfieldia amygdalina.We tested the hypothesis that excluding animals would significantly reduce seed removal,and increase both germination and seedling survival.The objective was to calculate a composite index of the relative suitability of the species studied for direct seeding.Methods Seeds were placed on the ground in a deforested site and subjected to five predator-exclusion treatments:wire cage,insecticide,cage+insecticide,open cage and no exclusion(control).Results Seed loss was highest for H.amygdalina(the largest seed tested).Across species,wire cages significantly reduced seed loss by 12.4%compared with controls(P<0.001)suggesting that vertebrates were the major seed predators.Seed germination ranged from 0 to 77%among the species tested.Based on relative species-performance scores(combining measures of survival and seedling growth),P.cerasoides was the most suitable species for direct seeding,followed by A.kurzii and C.axillaris,whilst H.dulcis and H.amygdalina were unsuitable.H.dulcis had small seeds with low seed germination,whereas H.amygdalina was subjected to high seed removal.Conclusion Exclusion of seed predators and the selection of suitable species may substantially increase the success of direct seeding,as a technique for restoring upland evergreen forest ecosystems.Testing more species for their suitability is needed,to provide more diverse options for forest restoration.展开更多
Comparative experiments were conducted on five conventional indica rice varieties,including Yongxian 15,Zhongzao 39,Shunda 135,Zhongzu 143,and Zhongzu 18.Under direct seeding conditions,their growth period and yield p...Comparative experiments were conducted on five conventional indica rice varieties,including Yongxian 15,Zhongzao 39,Shunda 135,Zhongzu 143,and Zhongzu 18.Under direct seeding conditions,their growth period and yield performance were investigated.The results showed that the yield of Zhonggang 143 and Shunda 135 was higher than that of Yongxian 15(CK),and Zhonggang 143 had the highest yield of 7.494 t/hm 2,followed by Shunda 135(7.467 t/hm 2);Yongxian 18(CK)has a yield of 7.326 t/hm 2.Taking into account factors such as field growth,yield,and growth period,Zhongzu 143 and Shunda 135 can be further promoted to optimize the early rice variety structure in Jiangbei District.展开更多
以牡丹籽壳为原料,利用大孔树脂和C18反相键合硅胶柱(C18柱)联合分离短叶松素,回收率为(98.33±0.64)%。用70%(体积分数)乙醇提取牡丹籽壳粗黄酮(Mu Dan Ke Flavonoids,MDKF),得率最高为(10.54±0.13)%;比较了6种大孔树脂(AB-8...以牡丹籽壳为原料,利用大孔树脂和C18反相键合硅胶柱(C18柱)联合分离短叶松素,回收率为(98.33±0.64)%。用70%(体积分数)乙醇提取牡丹籽壳粗黄酮(Mu Dan Ke Flavonoids,MDKF),得率最高为(10.54±0.13)%;比较了6种大孔树脂(AB-8、S-8、DM301、HPD600、HPD100和D101)的吸附率和解析率,发现S-8大孔树脂的吸附率和解析率最佳,分别为83.47%和84.46%;优化S-8大孔树脂分离MDKF的最佳条件为:上样液质量浓度1.6 mg/mL,上样液流速2.0 mL/min,洗脱剂乙醇体积分数60%,洗脱液流速1.5 mL/min,洗脱液体积100 mL;对经过C18柱分离后的组分进行LC-MS分析得到短叶松素,回收率为(98.33±0.64)%;分离前后抗氧化能力比较:C18纯化物>S-8大孔树脂纯化物>MDKF粗提物;分子对接实验表明,短叶松素与超氧化物歧化酶、过氧化氢酶、过氧化物酶、谷胱甘肽过氧化物酶均有结合能力,过氧化氢酶的结合能力最强为-9.1 kcal/mol。实验表明,短叶松素具有较好的抗氧化能力,可作为食品、药品或化妆品等抗氧化剂的添加,应用前景非常广泛,对牡丹籽壳的进一步开发利用提供理论支持。展开更多
巢式关联作图(Nested Association Mapping,NAM)群体在作物学遗传与育种研究中具有广泛的应用。本研究在前期大豆种质资源评价基础上,利用35份不同地区来源的代表性种质与中豆41(公共母本)杂交,构建了一套大豆NAM群体。PCA和聚类分析发...巢式关联作图(Nested Association Mapping,NAM)群体在作物学遗传与育种研究中具有广泛的应用。本研究在前期大豆种质资源评价基础上,利用35份不同地区来源的代表性种质与中豆41(公共母本)杂交,构建了一套大豆NAM群体。PCA和聚类分析发现,不同亲本组合的RIL群体基本聚在一起,显示出清晰的遗传结构。利用该NAM群体亲本间花色和种皮色具有显著差异的RIL群体进行全基因组关联分析,定位到1个主要位点qFC13-1与花色显著关联,该位点与W1位点重合;定位到12个位点与种皮色显著相关,其中9个位点为3种以上方法共定位,3个位点为2种方法共定位,包括4个已知位点和8个新位点。研究结果表明,构建的NAM群体适于进行大豆相关性状遗传分析,为大豆复杂性状的遗传解析和育种实践提供了良好的基础材料。展开更多
基金supported by China Agriculture Research System of MOF and MARA(CARS-34).
文摘The efficacies of biological and conventional chemical insecticides against two major insect pests of alfalfa(aphids and thrips)were compared in three sites across China’s alfalfa belt.In addition,the persistence of the residues of chemical insecticides in alfalfa and their influence on the quality of alfalfa hay were examined.Efficacy varied among the different biological and chemical insecticides.The chemical insecticides were significantly more effective than biopesticides in a short time-frame.The efficacy period of biopesticides was significantly longer than that of chemical insecticides,and the corrected mortality rate of aphids in all regions was above 50%at 14 days after application.The analysis of pesticide residues showed that the residual doses of all the pesticides were within the allowed ranges after the safe period.The acid detergent fiber and neutral detergent fiber contents in alfalfa hay were higher and the protein content was lower in chemical insecticide treatments than in biopesticide treatments in Hebei.The relative feeding value of alfalfa hay treated with Metarhizium anisopliae IPP330189 was the highest among the treatments.Compared with chemical insecticides,the yield of alfalfa hay was higher in the biopesticides treatments.Biopesticides show a stronger control effect on insect populations and also a better improvement in the quality of alfalfa hay than chemical insecticides.This study provides a basis for exploring and developing a comprehensive control regime for alfalfa insect pests in the different alfalfa-growing regions in China,and for reducing chemical insecticide usage and improving forage quality.
基金supported by the earmarked fund for China Agriculture Research System(CARS-02-16 and CARS-02-75)the National Key Research and Development Program of China(2016YFD0300301)。
文摘Planting under plastic-film mulches is widely used in spring maize production in arid-cold regions for water conservation and warming the soil.To ameliorate the associated issues such as plastic-film residues and additional labor during the“seedling release”in spring maize production,we have developed a plastic-film-side seeding(PSS)technology with the supporting machinery.In the semi-arid regions of Northwest China,a 7-year trial demonstrated that PSS increased plant number per hectare by 6547 and maize yield by 1686 kg ha–1compared with the traditional method of seeding under plastic-film mulch(PM).Two-year experiments were conducted in two semi-arid regions to further understand the effects of PSS on three important aspects of production:(i)the moisture and temperature of soil,(ii)maize development,yield output,and water use efficiency(WUE),and(iii)the revenue and plastic-film residuals in comparison with that of flat planting(CK)and PM.Continuous monitoring of the soil status demonstrated that,compared with CK,the PSS treatment significantly increased the temperature and moisture of the 0–20 cm soil in the seeding row at the early stage of maize development,and it also promoted grain yield(at 884–1089 kg ha^(–1))and WUE,achieving a similar effect as the PM treatment.Economically,the labor inputs of PSS were equal to CK,whereas the PM cost an additional 960 CNY ha–1in labor for releasing the seedlings from below the film.Overall,the PSS system increased profits by 5.83%(547 CNY ha^(–1)yr^(–1))and 8.16%(748 CNY ha^(–1)yr^(–1))compared with CK and PM,respectively.Environmentally,PSS achieved a residual film recovery rate of nearly 100%and eliminated 96 to 130 kg ha^(–1)of residual plastic-film in PM in 3–5 years of maize production.Collectively,these results show that PSS is an eco-friendly technique for improving yield stability and incomes for the sustainable production of maize in semi-arid regions.
基金supported by the National Natural Science Foundation of China(31971845 and 32101819)the earmarked fund for China Agriculture Research System(CARS-01-20)the China Postdoctoral Science Foundation(2021M691179)。
文摘Nitrogen(N) and seeding rates are important factors affecting grain yield and N use efficiency(NUE) in directseeded rice. However, these factors have not been adequately investigated on direct-seeded and double-season rice(DDR) in Central China. The objective of this study was to evaluate the effects of various N and seeding rates on the grain yield and NUE of an ultrashort-duration variety grown under DDR. Field experiments were conducted in 2018 in Wuxue County and 2019 in Qichun County, Hubei Province, China with four N rates and three seeding rates.The results showed that the grain yield of the ultrashort-duration variety ranged from 6.32 to 8.23 t ha–1with a total growth duration of 85 to 97 days across all treatments with N application. Grain yield was increased significantly by N application in most cases, but seeding rate had an inconsistent effect on grain yield. Furthermore, the response of grain yield to the N rates was much higher than the response to seeding rates. The moderate N rates of 100–150 and 70–120 kg N ha–1in the early and late seasons, respectively, could fully express the yield potential of the ultrashort-duration variety grown under DDR. Remarkably higher N responses and agronomic NUE levels were achieved in the early-season rice compared with the late-season rice due to the difference in indigenous soil N supply capacity(INS) between the two seasons. Seasonal differences in INS and N response should be considered when crop management practices are optimized for achieving high grain yield and NUE in ultrashort-duration variety grown under DDR.
基金This study was funded by the Thailand Research Fund(TRF Grant Number:MRG5980177),the Development and Promotion of Science and Technology Talents Project(Royal Thai Government Scholarship).Chiang Mai University partially supported this research,including the inputs of Stephen Elliott.
文摘Background Direct seeding is potentially a more cost-effective alternative to conventional tree planting for restoring tropical forest ecosystems.However,seed loss,due to removal and damage by animals,can substantially reduce seedling establishment.Therefore,this study examined the impact of seed predation on seedling establishment of five tree species,native to upland evergreen forests of northern Thailand:Hovenia dulcis,Alangium kurzii,Prunus cerasoides,Choerospondias axillaris and Horsfieldia amygdalina.We tested the hypothesis that excluding animals would significantly reduce seed removal,and increase both germination and seedling survival.The objective was to calculate a composite index of the relative suitability of the species studied for direct seeding.Methods Seeds were placed on the ground in a deforested site and subjected to five predator-exclusion treatments:wire cage,insecticide,cage+insecticide,open cage and no exclusion(control).Results Seed loss was highest for H.amygdalina(the largest seed tested).Across species,wire cages significantly reduced seed loss by 12.4%compared with controls(P<0.001)suggesting that vertebrates were the major seed predators.Seed germination ranged from 0 to 77%among the species tested.Based on relative species-performance scores(combining measures of survival and seedling growth),P.cerasoides was the most suitable species for direct seeding,followed by A.kurzii and C.axillaris,whilst H.dulcis and H.amygdalina were unsuitable.H.dulcis had small seeds with low seed germination,whereas H.amygdalina was subjected to high seed removal.Conclusion Exclusion of seed predators and the selection of suitable species may substantially increase the success of direct seeding,as a technique for restoring upland evergreen forest ecosystems.Testing more species for their suitability is needed,to provide more diverse options for forest restoration.
文摘Comparative experiments were conducted on five conventional indica rice varieties,including Yongxian 15,Zhongzao 39,Shunda 135,Zhongzu 143,and Zhongzu 18.Under direct seeding conditions,their growth period and yield performance were investigated.The results showed that the yield of Zhonggang 143 and Shunda 135 was higher than that of Yongxian 15(CK),and Zhonggang 143 had the highest yield of 7.494 t/hm 2,followed by Shunda 135(7.467 t/hm 2);Yongxian 18(CK)has a yield of 7.326 t/hm 2.Taking into account factors such as field growth,yield,and growth period,Zhongzu 143 and Shunda 135 can be further promoted to optimize the early rice variety structure in Jiangbei District.
文摘以牡丹籽壳为原料,利用大孔树脂和C18反相键合硅胶柱(C18柱)联合分离短叶松素,回收率为(98.33±0.64)%。用70%(体积分数)乙醇提取牡丹籽壳粗黄酮(Mu Dan Ke Flavonoids,MDKF),得率最高为(10.54±0.13)%;比较了6种大孔树脂(AB-8、S-8、DM301、HPD600、HPD100和D101)的吸附率和解析率,发现S-8大孔树脂的吸附率和解析率最佳,分别为83.47%和84.46%;优化S-8大孔树脂分离MDKF的最佳条件为:上样液质量浓度1.6 mg/mL,上样液流速2.0 mL/min,洗脱剂乙醇体积分数60%,洗脱液流速1.5 mL/min,洗脱液体积100 mL;对经过C18柱分离后的组分进行LC-MS分析得到短叶松素,回收率为(98.33±0.64)%;分离前后抗氧化能力比较:C18纯化物>S-8大孔树脂纯化物>MDKF粗提物;分子对接实验表明,短叶松素与超氧化物歧化酶、过氧化氢酶、过氧化物酶、谷胱甘肽过氧化物酶均有结合能力,过氧化氢酶的结合能力最强为-9.1 kcal/mol。实验表明,短叶松素具有较好的抗氧化能力,可作为食品、药品或化妆品等抗氧化剂的添加,应用前景非常广泛,对牡丹籽壳的进一步开发利用提供理论支持。
文摘巢式关联作图(Nested Association Mapping,NAM)群体在作物学遗传与育种研究中具有广泛的应用。本研究在前期大豆种质资源评价基础上,利用35份不同地区来源的代表性种质与中豆41(公共母本)杂交,构建了一套大豆NAM群体。PCA和聚类分析发现,不同亲本组合的RIL群体基本聚在一起,显示出清晰的遗传结构。利用该NAM群体亲本间花色和种皮色具有显著差异的RIL群体进行全基因组关联分析,定位到1个主要位点qFC13-1与花色显著关联,该位点与W1位点重合;定位到12个位点与种皮色显著相关,其中9个位点为3种以上方法共定位,3个位点为2种方法共定位,包括4个已知位点和8个新位点。研究结果表明,构建的NAM群体适于进行大豆相关性状遗传分析,为大豆复杂性状的遗传解析和育种实践提供了良好的基础材料。
