Using hybrid rice Yixiang1577 as the material, the mid-season and ratooning hybrid rice yield variation was studied in Southem Sichuan at different levels of nitrogen fertilizer. The results showed that rice yield by ...Using hybrid rice Yixiang1577 as the material, the mid-season and ratooning hybrid rice yield variation was studied in Southem Sichuan at different levels of nitrogen fertilizer. The results showed that rice yield by using N fertilizer increased to the most significant level than no fertilizer ones, and the mid-season rice and rice yield by using more N fertilizer increased to the significant level than less fertilizer ones. The rice yield by using no fertilizer ones increased to the most significant level than some used fertilizer, and the ratooning rice and rice yield by using more N fertilizer decreased to the most significant level than less fertilizer ones. The rice yield by using some fertilizer increased to the most significant level than no fertilizer ones for mid-season＋rationing rice and rice yield by using some fertilizer had no obvious differences at different nitrogen levels. Therefore, application of fertilizer can improve yield of mid-season rice and mid-season＋rationing rice. Soil test results showed that nutrient contents in rice field in South Sichuan were very rich in nitrogen, which could provide more adequate crop growth potential soil nitrogen nutrition. The crops with a deep root system had stronger ability of utilization on soil nitrogen. Therefore, the ratooning rice used no or little N fertilizer had a high yield performance because they made full use of soil nitrogen with deep root system.展开更多
Increased plant density with low N rate was a recommended strategy to increase grain yield and N use efficiency(NUE);however,grain yield,NUE and the total N uptake(TNU)responses of hybrid rice to this strategy at diff...Increased plant density with low N rate was a recommended strategy to increase grain yield and N use efficiency(NUE);however,grain yield,NUE and the total N uptake(TNU)responses of hybrid rice to this strategy at different yield levels(medium yielding site(MYS)Luzhou City and high yielding site(HYS)Deyang City had not been described.Field experiments with hybrid rice Rongyou1015 were conducted to study the effects of two plant densities.High plant density(HD),low plant density(LD)and four N rates(without N,N_(0);a recommended N rate of 195 kg•hm^(-2),N_(CK);a 23%reduction in N rate,N_(-23%);a 46%reduction in N rate,N_(-46%)on yield attributes,grain yield,TNU and NUE of hybrid rice were studied under different yield levels in 2016-2017.The results showed that the grain yield and NUE of hybrid rice in response to plant density and N rate varied with yield levels.For MYS,reducing N rate by 46%result in significantly lower grain yield at LD treatment;whereas at HD treatment the grain yield of hybrid rice under N_(-46%) and N_(CK) were equal.For HYS,reducing N rate by 46% result in significantly lower grain yield regardless of low plant density and high plant density;however,a reduction in N rate by 23%increased grain yield,AE_(N) by 36%,PFP_(N) by 31% and RE_(N) by 11% over N_(CK) at HD treatment.Higher grain yield of hybrid rice under the combination of HD with low N rate was attributable to improvement in spikelets per panicle and harvest index.The results suggested that high plant density with low N rate might be an effective approach to improve grain yield and NUE in rice production,but reduction in N application rate was determined,according to yield levels.展开更多
The effects of different amounts of carbon and nitrogen sources on the soil microbial biomass carbon,dissolved organic carbon and related enzyme activities were studied by the simulation experiment of rice straw retur...The effects of different amounts of carbon and nitrogen sources on the soil microbial biomass carbon,dissolved organic carbon and related enzyme activities were studied by the simulation experiment of rice straw returning to the field,and the mechanism of the decomposition of rice straw returning to the field was discussed.Completely randomized experiment of the two factors of the three levels was designed,and a total of nine treatments of indoor soil incubation tests were conducted.Full amount of rice straw was applied to the soil in this simulation experiment and different amounts of brown sugar and urea were added in the three levels of 0(no carbon source and nitrogen source),1(low levels of carbon and nitrogen sources)and 2(high levels of carbon and nitrogen sources),respectively.The results showed that the addition of different amounts of carbon and nitrogen sources to the rice straw could increase the soil carbon content.Compared with T0N0,the microbial biomass carbon of T2N2 was increased significantly by 170.48%;the dissolved organic carbon content of T1N2 was significantly increased by 58.14%and the free humic acid carbon contents of T0N2,T1N1 and T2N0 were significantly increased by 56.16%and 45.55%and 47.80%,respectively;however,there were no significant differences among those of treatments at later incubation periods.The addition of different carbon and nitrogen sources could promote the soil enzyme activities.During the incubation period,all of the soil enzyme activities of adding sugar and urea were higher than those of T0N0 treatment.Therefore,the addition of different amounts of carbon and nitrogen sources to rice straw returning could improve soil microbial biomass carbon content,dissolved organic carbon and soil enzyme activities.展开更多
The results of pot and pond trials are as follows.On equal amount of nitrogen(N)applied,the wheat nitrate reduction activity(NRA)and photosynthesis strength and other phy-siological properties are stronger and yields ...The results of pot and pond trials are as follows.On equal amount of nitrogen(N)applied,the wheat nitrate reduction activity(NRA)and photosynthesis strength and other phy-siological properties are stronger and yields are higher at normal soil moisture than those atdrought.At the same soil moisture,in a certain range of N applied,these properties of wheat in-crease with the increasing of N applied,but they descend when the amount of N applied exceedsa certain range.展开更多
有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M...有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M)和有机肥替代100%化肥氮(100%M) 6个处理,研究不同替代率对谷子产量构成和氮素吸收的影响,并分析氮素吸收调控小米米色、糊化特性和类胡萝卜素组分的效应,明确谷子生产中有机肥最佳替代率。结果表明,2年中较低的有机肥替代化肥氮率显著提高了谷子植株氮素累积,但随着替代率的持续增加,植株氮素累积量呈降低趋势,最终影响谷子产量和小米品质。2020年, 25%M处理显著提高了谷子地上部氮素累积量,较NPK处理提高9.6%;2021年,25%M处理谷子地上部氮素累积量、生物量、穗粒数和产量达到最高,较NPK处理分别提高6.1%、12.0%、15.4%和12.0%。50%M处理显著影响了小米的米色、糊化特征和类胡萝卜素含量,与NPK相比,小米籽粒红绿值、橘色值、支链淀粉含量、总淀粉含量、小米糊化最终黏度、叶黄素含量、玉米黄质含量和黄色素含量的增幅分别可达6.0%、6.0%、7.4%、4.3%、7.8%、20.7%、17.4%和2.8%。但有机肥完全替代化肥降低了谷子地上部氮素吸收、地上部生物量、穗粒数及谷子产量,也抑制了小米叶黄素和玉米黄质含量的提升。2年均表现出谷子地上部氮吸收量与小米单粒重、直链淀粉含量和小米糊化回升值呈显著的负相关。且2021年谷子地上部氮吸收量还与小米总淀粉含量、蛋白质含量、小米粉糊化峰值黏度和小米黄色素含量呈显著的负相关,与小米糊化峰谷黏度呈显著的正相关。综上,施氮总量120 kg hm^(–2)下,有机肥替代25%~50%化肥氮能通过促进植株氮素的吸收,实现产量、米色、蒸煮特性及类胡萝卜素的协同提升,为谷子化肥减量和提质增效生产提供技术支撑。展开更多
基金Supported by Rice Industry Technical System Construction Project from the Ministry of Agriculture
文摘Using hybrid rice Yixiang1577 as the material, the mid-season and ratooning hybrid rice yield variation was studied in Southem Sichuan at different levels of nitrogen fertilizer. The results showed that rice yield by using N fertilizer increased to the most significant level than no fertilizer ones, and the mid-season rice and rice yield by using more N fertilizer increased to the significant level than less fertilizer ones. The rice yield by using no fertilizer ones increased to the most significant level than some used fertilizer, and the ratooning rice and rice yield by using more N fertilizer decreased to the most significant level than less fertilizer ones. The rice yield by using some fertilizer increased to the most significant level than no fertilizer ones for mid-season＋rationing rice and rice yield by using some fertilizer had no obvious differences at different nitrogen levels. Therefore, application of fertilizer can improve yield of mid-season rice and mid-season＋rationing rice. Soil test results showed that nutrient contents in rice field in South Sichuan were very rich in nitrogen, which could provide more adequate crop growth potential soil nitrogen nutrition. The crops with a deep root system had stronger ability of utilization on soil nitrogen. Therefore, the ratooning rice used no or little N fertilizer had a high yield performance because they made full use of soil nitrogen with deep root system.
基金Supported by Earmarked Fund for Modern Agro-industry Technology of China(CARS-01-25)National Key Research and Development Program of China(2017YFD0301705)Foundation of Youth Science Program of Sichuan Agricultural Sciences Academy(2019QNJJ-020)。
文摘Increased plant density with low N rate was a recommended strategy to increase grain yield and N use efficiency(NUE);however,grain yield,NUE and the total N uptake(TNU)responses of hybrid rice to this strategy at different yield levels(medium yielding site(MYS)Luzhou City and high yielding site(HYS)Deyang City had not been described.Field experiments with hybrid rice Rongyou1015 were conducted to study the effects of two plant densities.High plant density(HD),low plant density(LD)and four N rates(without N,N_(0);a recommended N rate of 195 kg•hm^(-2),N_(CK);a 23%reduction in N rate,N_(-23%);a 46%reduction in N rate,N_(-46%)on yield attributes,grain yield,TNU and NUE of hybrid rice were studied under different yield levels in 2016-2017.The results showed that the grain yield and NUE of hybrid rice in response to plant density and N rate varied with yield levels.For MYS,reducing N rate by 46%result in significantly lower grain yield at LD treatment;whereas at HD treatment the grain yield of hybrid rice under N_(-46%) and N_(CK) were equal.For HYS,reducing N rate by 46% result in significantly lower grain yield regardless of low plant density and high plant density;however,a reduction in N rate by 23%increased grain yield,AE_(N) by 36%,PFP_(N) by 31% and RE_(N) by 11% over N_(CK) at HD treatment.Higher grain yield of hybrid rice under the combination of HD with low N rate was attributable to improvement in spikelets per panicle and harvest index.The results suggested that high plant density with low N rate might be an effective approach to improve grain yield and NUE in rice production,but reduction in N application rate was determined,according to yield levels.
基金Supported by the National Key Research and Development Plan Project(2016YFD0300909-04)。
文摘The effects of different amounts of carbon and nitrogen sources on the soil microbial biomass carbon,dissolved organic carbon and related enzyme activities were studied by the simulation experiment of rice straw returning to the field,and the mechanism of the decomposition of rice straw returning to the field was discussed.Completely randomized experiment of the two factors of the three levels was designed,and a total of nine treatments of indoor soil incubation tests were conducted.Full amount of rice straw was applied to the soil in this simulation experiment and different amounts of brown sugar and urea were added in the three levels of 0(no carbon source and nitrogen source),1(low levels of carbon and nitrogen sources)and 2(high levels of carbon and nitrogen sources),respectively.The results showed that the addition of different amounts of carbon and nitrogen sources to the rice straw could increase the soil carbon content.Compared with T0N0,the microbial biomass carbon of T2N2 was increased significantly by 170.48%;the dissolved organic carbon content of T1N2 was significantly increased by 58.14%and the free humic acid carbon contents of T0N2,T1N1 and T2N0 were significantly increased by 56.16%and 45.55%and 47.80%,respectively;however,there were no significant differences among those of treatments at later incubation periods.The addition of different carbon and nitrogen sources could promote the soil enzyme activities.During the incubation period,all of the soil enzyme activities of adding sugar and urea were higher than those of T0N0 treatment.Therefore,the addition of different amounts of carbon and nitrogen sources to rice straw returning could improve soil microbial biomass carbon content,dissolved organic carbon and soil enzyme activities.
文摘The results of pot and pond trials are as follows.On equal amount of nitrogen(N)applied,the wheat nitrate reduction activity(NRA)and photosynthesis strength and other phy-siological properties are stronger and yields are higher at normal soil moisture than those atdrought.At the same soil moisture,in a certain range of N applied,these properties of wheat in-crease with the increasing of N applied,but they descend when the amount of N applied exceedsa certain range.
文摘有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M)和有机肥替代100%化肥氮(100%M) 6个处理,研究不同替代率对谷子产量构成和氮素吸收的影响,并分析氮素吸收调控小米米色、糊化特性和类胡萝卜素组分的效应,明确谷子生产中有机肥最佳替代率。结果表明,2年中较低的有机肥替代化肥氮率显著提高了谷子植株氮素累积,但随着替代率的持续增加,植株氮素累积量呈降低趋势,最终影响谷子产量和小米品质。2020年, 25%M处理显著提高了谷子地上部氮素累积量,较NPK处理提高9.6%;2021年,25%M处理谷子地上部氮素累积量、生物量、穗粒数和产量达到最高,较NPK处理分别提高6.1%、12.0%、15.4%和12.0%。50%M处理显著影响了小米的米色、糊化特征和类胡萝卜素含量,与NPK相比,小米籽粒红绿值、橘色值、支链淀粉含量、总淀粉含量、小米糊化最终黏度、叶黄素含量、玉米黄质含量和黄色素含量的增幅分别可达6.0%、6.0%、7.4%、4.3%、7.8%、20.7%、17.4%和2.8%。但有机肥完全替代化肥降低了谷子地上部氮素吸收、地上部生物量、穗粒数及谷子产量,也抑制了小米叶黄素和玉米黄质含量的提升。2年均表现出谷子地上部氮吸收量与小米单粒重、直链淀粉含量和小米糊化回升值呈显著的负相关。且2021年谷子地上部氮吸收量还与小米总淀粉含量、蛋白质含量、小米粉糊化峰值黏度和小米黄色素含量呈显著的负相关,与小米糊化峰谷黏度呈显著的正相关。综上,施氮总量120 kg hm^(–2)下,有机肥替代25%~50%化肥氮能通过促进植株氮素的吸收,实现产量、米色、蒸煮特性及类胡萝卜素的协同提升,为谷子化肥减量和提质增效生产提供技术支撑。
