With indica ( Oryza sativa L.) hybrid Shanyou 63 as control, the hybrid rice varieties including Peiai 64S/E32, Peiai 64S/9311, X07S/Zihui 100, Guangyou 881 and japonica 9516 were used to study changes of chlorophyll ...With indica ( Oryza sativa L.) hybrid Shanyou 63 as control, the hybrid rice varieties including Peiai 64S/E32, Peiai 64S/9311, X07S/Zihui 100, Guangyou 881 and japonica 9516 were used to study changes of chlorophyll content, photosynthetic response to light intensity and temperature, chlorophyll fluorescence characteristics and membrane lipid peroxidation in their flag leaves at the late stage of development under natural conditions in Nanjing. The results were as follows:. primary photochemical efficiency of PS II ( F-v / F-m), quantum yield of linear electron transport of PS II (phi(PSII)), electron transfer rate (ETR) in these rice varieties decreased with their decrease of chlorophyll content during this period. This kind of impediment to energy conversion induced the transfer of excessive energy to the reducing side of PS I, hence the accumulation of O-2(radical anion) and peroxidation of membrane lipid, and resulting in the accumulation of malondialdehyde (MDA), that is the destroys of photosynthetic pigments and membranes and the consequent, premature senescence. This phenomenon is variable conspicuously in different rice varieties. Under natural condition in Nanjing, F-v/F-m, phi(PSII), ETR and quenching coefficient ( qP) in japonica 9516 tolerant to photooxidation decreased less and the conversion capacity of light energy was stable, premature senescence was unlikely, and consequently the seed-setting rate was higher. While F-v/F-m, phi(PSII), ETR and photochemical qP in Shanyou 63 sensitive to photooxidation decreased more and therefore premature senescence was easy to happen, thus the seed-setting rate and yield were all reduced. The tolerance to photooxidation and premature senescence in other hybrids derived from typical two line or three line crossing laid in the middle. From the rice breeding for super-high-yield, on the basis of the good plant-type of current rice, considering both hybrid vigor and the prevention premature senescence, it would be a notable strategy to use japonica maternal line or maternal. lines with some japonica genotype as the sterile lines in rice breeding.展开更多
To understand the high yield and efficiency technique in hybrid rice Zhongzheyou No. 1, we conducted the correlation analysis, regression analysis and path analysis of hybrid rice Zhongzheyou No. 1 based on the data o...To understand the high yield and efficiency technique in hybrid rice Zhongzheyou No. 1, we conducted the correlation analysis, regression analysis and path analysis of hybrid rice Zhongzheyou No. 1 based on the data of its ear, grain and weight at different yield levels. From this study, we put forward the high yield and efficiency technique in Zhongzheyou No. 1 .. on the basis of certain effective ear number, filled grains per ear should be mainly targeted with a consideration to 1 000-grain weight.展开更多
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
Activities of several key enzymes of C-4 photosynthesis pathway and stable carbon isotope discrimination were investigated in flag leaves of a super high-yield hybrid rice (Oryza sativa L.) cv. Peiai 64S/E32 and a tra...Activities of several key enzymes of C-4 photosynthesis pathway and stable carbon isotope discrimination were investigated in flag leaves of a super high-yield hybrid rice (Oryza sativa L.) cv. Peiai 64S/E32 and a traditional hybrid rice cv. Shanyou 63 at different developing stages. Results show that the activity of PEP carboxylase (PEPCase) increased with age of flag leave; the activity of NADP-malate dehydrogenase (NADP-MDH) increased and reached to a peak value at grain filling stage (68-75 d after transplanting), then fell down; the activity of NADP-MDH in cv. Peiai 64S/E32 was much higher than that in cv. Shanyou 63. Before ripening stage (95 d after transplanting), NADP-malic enzyme activity rose gradually. The level of stable carbon isotope discrimination (Delta(13)C) in flag leaves and grains at different developing stages were similar and exhibited a comparative high value at ripening stage. The average Delta(13)C in leaf of cv. Peiai 64S/E32 during different developing stages was 0.43parts per thousand more than that in cv. Shanyou 63.展开更多
[Objective] This study aimed to investigate the high-yielding seed production technologies of japonica hybrid rice. [Method] Key technologies affecting the seed production of japonica hybrid rice were investigated bas...[Objective] This study aimed to investigate the high-yielding seed production technologies of japonica hybrid rice. [Method] Key technologies affecting the seed production of japonica hybrid rice were investigated based on manual transplanting experiment, mechanical transplanting experiment, paclobutrazol chemical control experiment, leaf-clipping experiment, gibberellic acid treatment experiment and experiment of different row ratios of male and female parents. [Result] The duration from seeding to heading was significantly shortened with sowing date postponing. The sowing date of mechanical-transplanting parents should be 3 -4 d earlier than that of manual-transplanting parents. Spraying paclobutrazol had significantly control effect on plant height of rice seedlings, and the spraying dose should be determined based on the sensitivities of different parents to paclobutrazol, with an appropriate range of 600-900 g/hm2 . Leaf clipping had certain improving effect on the seed-setting rate. The appropriate spraying dose of gibberellin for japonica hybrid rice was 75-90 g/hm2 . The yield would be relatively high when row ratio of male and female parent was 6∶2. [Conclusion] This study laid the foundation for improving the yield of produced japonica hybrid rice seeds.展开更多
To clarify the influencing factors of rice production and interaction among the factors in Heilongjiang Province, the productivity, characteristics and yield com- ponents and fertilizer tolerability of main rice culti...To clarify the influencing factors of rice production and interaction among the factors in Heilongjiang Province, the productivity, characteristics and yield com- ponents and fertilizer tolerability of main rice cultivars in HeUongjiang for decades were analyzed. The rice production was divided into four basic growth stages, and the representative cultivars of each stage were Hejiang 19, Hejiang 23, Kongyu 131 and Longjing 31. The results showed that grain number per panicle, seed setting rate and thousand seed weight had no significant difference among yield compo- nents of the four main cultivars, the increase of grain number per panicle was the key factor of yield increasing. The disease resistance, lodging resistance and fertiliz- er absorption ability increased. By the analysis, the author suggested increasing the grain number per panicle in breeding, enhancing organic fertilizer application in culti- vation and improving nitrogen fertilizer use efficiency.展开更多
Thylakoid membrane preparations of super high-yield hybrid rice (Oryza sativa L.), Liangyoupeijiu (P9) and Shanyou 63 (SH 63) were used for investigating its spectral and time properties by using picosecond time-resol...Thylakoid membrane preparations of super high-yield hybrid rice (Oryza sativa L.), Liangyoupeijiu (P9) and Shanyou 63 (SH 63) were used for investigating its spectral and time properties by using picosecond time-resolved fluorescence spectrum measuring system. The thylakoid membrane preparations of P9 and SH 63 were excited by an Ar+ laser with a pulse width of 120 ps, repetition rate of 4 MHz and wavelength of 514 nm. The time constants of the excited energy transfer in these two varieties at flowering stage and grain filling stage were calculated from the experimental data. Based on the comparative studies of the time and spectral properties of the excited fluorescence in these ultrafast dynamic experiments the following was found: at both the flowering stage and grain filling stage, the speed of the excitation energy transfer, in photosystem was faster than that in photosystem II in P9 variety; and the speed of the excitation energy transfer at grain filling stage was faster than those at flowering stage for both rice varieties; the experiments also implied that the components and assembly of pigments in SH 63, but not in P9, changed during the process from flowering stage to grain filling stage for in these two rice varieties.展开更多
[Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of ...[Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of rice were studied by pot experiment with cultivating rice. [Result] Pb and Cd could promote rice growth at low concentration while inhibit plant height at high concentration; Pb and Cd stress reduced the number of rice tillers significantly,with the increasing of stress concentration,the decrease amplitude of the number of tillers was greater; the panicle per pot,seed setting rate,1 000-grain weight and yield of rice were reduced significantly by Pb and Cd stress,the grain number per panicle decreased significantly under low concentration of Pb and Cd but increased significantly under high concentration; the brown rice rate and milled rice rate increased significantly under low concentration of Pb and Cd while at high concentration of Pb and Cd,the both two reduced significantly,the head milled rice rate reduced significantly with the decreasing of concentration; The Pb and Cd content of grains were significantly positively related to the concentrations of Pb and Cd content in soil,it had excessively exceeded hygienic standard when the concentrations of Pb and Cd in soil were medium-high and the unqualified rate reached 333% and 122%. [Conclusion]The study had provided basis for the establishment of rice cultivation system in pollution areas.展开更多
[Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertil...[Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertilization technology of Lvhan No.l, a new cultivar of earlier ripe and drought resistant rice, was researched in CATETE farm of Luanda suburb with pot experiment method. [Result] In CATETE farm, Lvhan No.1 rice were directly sown in black clay and the rice can be significantly improved in plant height, grain weight of single plant, biological yield of single plant, ear length, total grain number per ear, number of filled grain per ear and thousand seed weight, as well as economic coefficient and ratio of grain to straw, if applied with base fertilizer made up of DAP (N:P2Os=14:43), or compound fertilizer of N, P and K (N:P2Os:K^O=15:15:15) and with Duannai fertilizer and ear-grain fertilizer made up of urea. If DAP is taken as base fertilizer, the optimal quantity is 300 kg/hm2. If compound fertilizer of N, P and K is taken as base fertilizer, the optimal quantity is 450 kg/hm2, but urea at 75 kg/hm2 should be applied as Duannai fertilizer and ear- grain fertilizer, respectively, on time. [Conclusion] The research provides technical ref- erences for planting of Chinese rice cultivars in Angola.展开更多
The effects of nitrogen, phosphorus and potassium application level, seed rate and transplanting density on the growth and development of rice plants were studied to find out nutrient status in high-yielding rice plan...The effects of nitrogen, phosphorus and potassium application level, seed rate and transplanting density on the growth and development of rice plants were studied to find out nutrient status in high-yielding rice plants and to increase grain yield by adequate fertilization. There was an equilibrium relationship among nutrient elements for high-yielding rice plant populations. The equilibrium index of nutrient amount, content and distribution in high-yielding rice plants should be generally greater than-2 but less than 2. The optimum nutritive proportion of nitrogen: phosphorus: potassium assimilated by the plants was about 10: 2: 9 at the ripening stage. But the content and the proportion varied with the growth stages. Therefore, the nutrient in rice plant populations should be in a dynamic equilibrium, so as to achieve high yield.展开更多
Rice ratooning refers to the production of second crop from the stubble after the harvest of main crop. Main and ratoon rice growth and development are affected by different factors. These factors include varieties se...Rice ratooning refers to the production of second crop from the stubble after the harvest of main crop. Main and ratoon rice growth and development are affected by different factors. These factors include varieties selection, water management,fertilizer management, stubble height, plant protection practices and external environmental factors such as temperature and light.In this review, we discussed the different factors affecting the yield and yield components of main and ratoon rice. Among these factors the most important and first one is varietal selection. Varieties should be selected according to the requirement of specific area and prefer varieties resistant to insects/pests and diseases. Sufficient amount of water and fertilizer should be supplied.Stubble height of 10-20 cm will resulted in high production of ratoon rice. Too low or too high temperature and light would reduce the grain yield and quality of rice. Optimal temperature is useful for higher yield. It was concluded that by keeping the management practices more efficiently, the yield of main rice as well as ratoon rice could be increased. There is a need of more studies focusing on improvement of the quality of ratoon rice.展开更多
Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-...Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.展开更多
Optimized high-yielding cultivation is of great significance to ensure stable and high yield of rice in China. This paper reviewed several super high-yielding cultivation modes, analyzed the effects of different culti...Optimized high-yielding cultivation is of great significance to ensure stable and high yield of rice in China. This paper reviewed several super high-yielding cultivation modes, analyzed the effects of different cultivation modes on rice agronomic traits and physiological characteristics, and discussed the advances in rice mechanized cultivation and mode. Finally, the future development prospects of rice cultivation were put forward.展开更多
文摘With indica ( Oryza sativa L.) hybrid Shanyou 63 as control, the hybrid rice varieties including Peiai 64S/E32, Peiai 64S/9311, X07S/Zihui 100, Guangyou 881 and japonica 9516 were used to study changes of chlorophyll content, photosynthetic response to light intensity and temperature, chlorophyll fluorescence characteristics and membrane lipid peroxidation in their flag leaves at the late stage of development under natural conditions in Nanjing. The results were as follows:. primary photochemical efficiency of PS II ( F-v / F-m), quantum yield of linear electron transport of PS II (phi(PSII)), electron transfer rate (ETR) in these rice varieties decreased with their decrease of chlorophyll content during this period. This kind of impediment to energy conversion induced the transfer of excessive energy to the reducing side of PS I, hence the accumulation of O-2(radical anion) and peroxidation of membrane lipid, and resulting in the accumulation of malondialdehyde (MDA), that is the destroys of photosynthetic pigments and membranes and the consequent, premature senescence. This phenomenon is variable conspicuously in different rice varieties. Under natural condition in Nanjing, F-v/F-m, phi(PSII), ETR and quenching coefficient ( qP) in japonica 9516 tolerant to photooxidation decreased less and the conversion capacity of light energy was stable, premature senescence was unlikely, and consequently the seed-setting rate was higher. While F-v/F-m, phi(PSII), ETR and photochemical qP in Shanyou 63 sensitive to photooxidation decreased more and therefore premature senescence was easy to happen, thus the seed-setting rate and yield were all reduced. The tolerance to photooxidation and premature senescence in other hybrids derived from typical two line or three line crossing laid in the middle. From the rice breeding for super-high-yield, on the basis of the good plant-type of current rice, considering both hybrid vigor and the prevention premature senescence, it would be a notable strategy to use japonica maternal line or maternal. lines with some japonica genotype as the sterile lines in rice breeding.
文摘To understand the high yield and efficiency technique in hybrid rice Zhongzheyou No. 1, we conducted the correlation analysis, regression analysis and path analysis of hybrid rice Zhongzheyou No. 1 based on the data of its ear, grain and weight at different yield levels. From this study, we put forward the high yield and efficiency technique in Zhongzheyou No. 1 .. on the basis of certain effective ear number, filled grains per ear should be mainly targeted with a consideration to 1 000-grain weight.
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Activities of several key enzymes of C-4 photosynthesis pathway and stable carbon isotope discrimination were investigated in flag leaves of a super high-yield hybrid rice (Oryza sativa L.) cv. Peiai 64S/E32 and a traditional hybrid rice cv. Shanyou 63 at different developing stages. Results show that the activity of PEP carboxylase (PEPCase) increased with age of flag leave; the activity of NADP-malate dehydrogenase (NADP-MDH) increased and reached to a peak value at grain filling stage (68-75 d after transplanting), then fell down; the activity of NADP-MDH in cv. Peiai 64S/E32 was much higher than that in cv. Shanyou 63. Before ripening stage (95 d after transplanting), NADP-malic enzyme activity rose gradually. The level of stable carbon isotope discrimination (Delta(13)C) in flag leaves and grains at different developing stages were similar and exhibited a comparative high value at ripening stage. The average Delta(13)C in leaf of cv. Peiai 64S/E32 during different developing stages was 0.43parts per thousand more than that in cv. Shanyou 63.
基金Supported by National 863 Project of China"Creation and Application of Highly Dominant Japonica Hybrids"(2011AA10A101)~~
文摘[Objective] This study aimed to investigate the high-yielding seed production technologies of japonica hybrid rice. [Method] Key technologies affecting the seed production of japonica hybrid rice were investigated based on manual transplanting experiment, mechanical transplanting experiment, paclobutrazol chemical control experiment, leaf-clipping experiment, gibberellic acid treatment experiment and experiment of different row ratios of male and female parents. [Result] The duration from seeding to heading was significantly shortened with sowing date postponing. The sowing date of mechanical-transplanting parents should be 3 -4 d earlier than that of manual-transplanting parents. Spraying paclobutrazol had significantly control effect on plant height of rice seedlings, and the spraying dose should be determined based on the sensitivities of different parents to paclobutrazol, with an appropriate range of 600-900 g/hm2 . Leaf clipping had certain improving effect on the seed-setting rate. The appropriate spraying dose of gibberellin for japonica hybrid rice was 75-90 g/hm2 . The yield would be relatively high when row ratio of male and female parent was 6∶2. [Conclusion] This study laid the foundation for improving the yield of produced japonica hybrid rice seeds.
基金Supported by Sustainable Yielding and Highly-efficient Technology Integration,Innovation and Demonstration for Spring Maize and Spring Rice in the Northeast China Plain(2011BAD16B11)~~
文摘To clarify the influencing factors of rice production and interaction among the factors in Heilongjiang Province, the productivity, characteristics and yield com- ponents and fertilizer tolerability of main rice cultivars in HeUongjiang for decades were analyzed. The rice production was divided into four basic growth stages, and the representative cultivars of each stage were Hejiang 19, Hejiang 23, Kongyu 131 and Longjing 31. The results showed that grain number per panicle, seed setting rate and thousand seed weight had no significant difference among yield compo- nents of the four main cultivars, the increase of grain number per panicle was the key factor of yield increasing. The disease resistance, lodging resistance and fertiliz- er absorption ability increased. By the analysis, the author suggested increasing the grain number per panicle in breeding, enhancing organic fertilizer application in culti- vation and improving nitrogen fertilizer use efficiency.
文摘Thylakoid membrane preparations of super high-yield hybrid rice (Oryza sativa L.), Liangyoupeijiu (P9) and Shanyou 63 (SH 63) were used for investigating its spectral and time properties by using picosecond time-resolved fluorescence spectrum measuring system. The thylakoid membrane preparations of P9 and SH 63 were excited by an Ar+ laser with a pulse width of 120 ps, repetition rate of 4 MHz and wavelength of 514 nm. The time constants of the excited energy transfer in these two varieties at flowering stage and grain filling stage were calculated from the experimental data. Based on the comparative studies of the time and spectral properties of the excited fluorescence in these ultrafast dynamic experiments the following was found: at both the flowering stage and grain filling stage, the speed of the excitation energy transfer, in photosystem was faster than that in photosystem II in P9 variety; and the speed of the excitation energy transfer at grain filling stage was faster than those at flowering stage for both rice varieties; the experiments also implied that the components and assembly of pigments in SH 63, but not in P9, changed during the process from flowering stage to grain filling stage for in these two rice varieties.
基金Supported by the Program of Ministry of Environmental Protection(200809093 )the Significant Science Planning Program of Guangdong Province (2008A080800028)~~
文摘[Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of rice were studied by pot experiment with cultivating rice. [Result] Pb and Cd could promote rice growth at low concentration while inhibit plant height at high concentration; Pb and Cd stress reduced the number of rice tillers significantly,with the increasing of stress concentration,the decrease amplitude of the number of tillers was greater; the panicle per pot,seed setting rate,1 000-grain weight and yield of rice were reduced significantly by Pb and Cd stress,the grain number per panicle decreased significantly under low concentration of Pb and Cd but increased significantly under high concentration; the brown rice rate and milled rice rate increased significantly under low concentration of Pb and Cd while at high concentration of Pb and Cd,the both two reduced significantly,the head milled rice rate reduced significantly with the decreasing of concentration; The Pb and Cd content of grains were significantly positively related to the concentrations of Pb and Cd content in soil,it had excessively exceeded hygienic standard when the concentrations of Pb and Cd in soil were medium-high and the unqualified rate reached 333% and 122%. [Conclusion]The study had provided basis for the establishment of rice cultivation system in pollution areas.
基金Supported by International Cooperation Program of Anhui Provincial Science&Technology Department(11030603031)~~
文摘[Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertilization technology of Lvhan No.l, a new cultivar of earlier ripe and drought resistant rice, was researched in CATETE farm of Luanda suburb with pot experiment method. [Result] In CATETE farm, Lvhan No.1 rice were directly sown in black clay and the rice can be significantly improved in plant height, grain weight of single plant, biological yield of single plant, ear length, total grain number per ear, number of filled grain per ear and thousand seed weight, as well as economic coefficient and ratio of grain to straw, if applied with base fertilizer made up of DAP (N:P2Os=14:43), or compound fertilizer of N, P and K (N:P2Os:K^O=15:15:15) and with Duannai fertilizer and ear-grain fertilizer made up of urea. If DAP is taken as base fertilizer, the optimal quantity is 300 kg/hm2. If compound fertilizer of N, P and K is taken as base fertilizer, the optimal quantity is 450 kg/hm2, but urea at 75 kg/hm2 should be applied as Duannai fertilizer and ear- grain fertilizer, respectively, on time. [Conclusion] The research provides technical ref- erences for planting of Chinese rice cultivars in Angola.
文摘The effects of nitrogen, phosphorus and potassium application level, seed rate and transplanting density on the growth and development of rice plants were studied to find out nutrient status in high-yielding rice plants and to increase grain yield by adequate fertilization. There was an equilibrium relationship among nutrient elements for high-yielding rice plant populations. The equilibrium index of nutrient amount, content and distribution in high-yielding rice plants should be generally greater than-2 but less than 2. The optimum nutritive proportion of nitrogen: phosphorus: potassium assimilated by the plants was about 10: 2: 9 at the ripening stage. But the content and the proportion varied with the growth stages. Therefore, the nutrient in rice plant populations should be in a dynamic equilibrium, so as to achieve high yield.
基金Supported by the National Basic Research Program of China(2016YFD0300208)
文摘Rice ratooning refers to the production of second crop from the stubble after the harvest of main crop. Main and ratoon rice growth and development are affected by different factors. These factors include varieties selection, water management,fertilizer management, stubble height, plant protection practices and external environmental factors such as temperature and light.In this review, we discussed the different factors affecting the yield and yield components of main and ratoon rice. Among these factors the most important and first one is varietal selection. Varieties should be selected according to the requirement of specific area and prefer varieties resistant to insects/pests and diseases. Sufficient amount of water and fertilizer should be supplied.Stubble height of 10-20 cm will resulted in high production of ratoon rice. Too low or too high temperature and light would reduce the grain yield and quality of rice. Optimal temperature is useful for higher yield. It was concluded that by keeping the management practices more efficiently, the yield of main rice as well as ratoon rice could be increased. There is a need of more studies focusing on improvement of the quality of ratoon rice.
文摘Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.
基金Supported by Key Laboratory of Pesticide Harmless Application of Hunan ProvinceScience and Technology Plan Project of Loudi City(201601)
文摘Optimized high-yielding cultivation is of great significance to ensure stable and high yield of rice in China. This paper reviewed several super high-yielding cultivation modes, analyzed the effects of different cultivation modes on rice agronomic traits and physiological characteristics, and discussed the advances in rice mechanized cultivation and mode. Finally, the future development prospects of rice cultivation were put forward.