Hybrid rice Xinhunyou No. 6 could be cultivated by mixing male and fe- male parents and performing seedling raising followed by transplanting, mechanical planting or mechanical direct seeding according to the producti...Hybrid rice Xinhunyou No. 6 could be cultivated by mixing male and fe- male parents and performing seedling raising followed by transplanting, mechanical planting or mechanical direct seeding according to the production methods of com- mercial rice. During flowering stage, leaf cutting, application of ＂920＂ and pollination were conducted; after pollination, bentazon with a certain concentration was sprayed to kill the male parent; and the hybrid rice was harvested mechanically. Before storage, color separation was performed to remove little remaining male parent, thereby achieving whole-process mechanization of hybrid rice seed production. This study introduced mechanized seed production of Xinhunyou No. 6 through mixed- seeding from the aspects including mechanical direct seeding, seeding raising fol- lowed by transplanting and mechanical planting.展开更多
[Objectives]Current hybrid rice seed production mechanization and a new kind of hybrid rice seed production mechanization using Bentazone sensitive lethal genes for mechanized seed production technology are introduced...[Objectives]Current hybrid rice seed production mechanization and a new kind of hybrid rice seed production mechanization using Bentazone sensitive lethal genes for mechanized seed production technology are introduced in this paper.[Method]Sensitive Restorer Bentazone lethal dose of filtering,parental and seed weight are bred combinations of several aspects of the system described,and presented mechanized seed technology new research directions.[Results]The method of using Bentazone sensitive lethal genes for mechanized seed production technology is feasible,economic,seed production and combination advantages.[Conclusions] Using Bentazone sensitive lethal genes for mechanized seed production technology is the new study direction of mechanic production.展开更多
[Objective] The aim was to study the reproduction of the three-line genic male sterile （GMS） lineparent Mian7MB-1 （B. NapusL.） and the seed production of F1 through somatic tissue culture. [Methed] Through hybridi...[Objective] The aim was to study the reproduction of the three-line genic male sterile （GMS） lineparent Mian7MB-1 （B. NapusL.） and the seed production of F1 through somatic tissue culture. [Methed] Through hybridization, a new breeding material Mian 7MB-1 in three-line genic temporary maintainer line propagated by tissue culture was used to improve the sterile plant rate of rapeseed in dual-purpose recessive GMS line, such as Mian 7AB type, S45AB type, and etc. And then the variety comparative test was performed. [Result] In order to avoid some fertility restoration phenomena occurring during the process of self-reproduction, Mian 7AB was propagated in bulk with somatic tissue culture of temporary maintainer line plant stem. The propagated temporary maintainer line seedlings were applied to the breeding and seed production of net room male sterile line parent, promoting the sterile plant rate of the male sterile line parent to 91.7% -93.5%. The male sterile line parents per hectare were enough for the seed production of hybrid F1 in 7 500 -15 000 hm^2. [ Conclusion ] Compared with the original dual-purpose GMS line, the seed production ultilizing male sterile line with high sterile plant rate greatly reduced the labor, significantly improved the seed yield, ensuring the seed quality and forming a perfect breeding and seed production system.展开更多
The insecure problems of seed production have seriously hampered the healthy and sustainable development of two-line hybrid rice.The safety issues on seed production of two-line hybrid rice and current research situat...The insecure problems of seed production have seriously hampered the healthy and sustainable development of two-line hybrid rice.The safety issues on seed production of two-line hybrid rice and current research situation were pointed out in this paper.The three main reasons for unsafety in seed production of twoline hybrid rice were unsuitable site selection,high critical sterility-inducing temperature and the drift of critical temperature.In this paper,strategies and measures were put forward based on many years of practice.It could minimize the risk in seed production of two-line hybrid rice by selecting dual-purpose genic male sterile line with lower critical sterility-inducing temperature and long lower temperature resistant time.Based on the climate data and climatic demands of the ＂three safe-periods＂ in seed production,a new idea for determining appropriate bases and periods for seed production was proposed by using computer technology,which solved the aimless selection of sites and periods for the seed production of two-line hybrid rice.Besides,we established a system of single plant selection and identification method and original seed propagation with cyclic cold water,which could reduce the generation number of original seed propagation in seed production and avoid the drift of critical sterility-inducing temperature.This paper improved the seed production safety in the three aspects of seed nature,seed source and seed production site.展开更多
The seed production of male and female parent of ‘Hunzhi 1＇ contained bentazon susceptible gene was studied. The result showed that spraying 3. 375 L/hm2 48% bentazon aqua could control the self-pollinated fertiliza...The seed production of male and female parent of ‘Hunzhi 1＇ contained bentazon susceptible gene was studied. The result showed that spraying 3. 375 L/hm2 48% bentazon aqua could control the self-pollinated fertilization rate below 1.0% and survival plant rate was 0. The spray of bentazon would not influence MC526 pollen vitality. Seed setting rate of female parent was not obvious different from that of control group with spraying bentazon aqua more than 3. 375 L/hm^2 from the sprouting appearing period to full heading stage. This demonstrated that bentazon aqua had no influence on seed setting rate during florescence of female parent. The weight ratio between male parent seeds and female parent seeds was 1 to 5, then seeds from parents with that weight ratio would be mixedly planted for seed production. With this weight ratio, relative proper structure of panicle and grain would be obtained ,panicle ratio was 1 to 4.3, glumous flowers ratio was 1 to 3.5. Cross seed-setting rate of female parent was 72.6% and seed production per hm^2 was 66 000 kg.展开更多
Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The resea...Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The research progress on mixed sowing seed production techniques of hybrid rice was introduced from the aspects of rice resources creation, breeding, sowing seed technology research and cost benefit analysis. The production technology of the new mixed seeding combina- tion ＂Xinhunyou 6＂ was investigated, including the research and validation of benta- zon treatment period and dosage, mixing ratio of male and female parents, and the comparative test of different different sowing methods, which revealed that the mechanization technology of seed production of hybrid rice was mature and feasible and would be one of the most important development trend of technological devel- opment of hybrid rice production.展开更多
In order to study the effects of mechanized transplanting and fertilization mode on population growth and development of the male parent in seed production of hybrid rice, three male parents, Huazhan, Shuhui 527 and R...In order to study the effects of mechanized transplanting and fertilization mode on population growth and development of the male parent in seed production of hybrid rice, three male parents, Huazhan, Shuhui 527 and R9311 were selected as materials. The male parents were transplanted by rice transplanter with two kinds of line spacing design, six lines with equal row spacing （20/25 cm x 30 cm） and wide and narrow spacing （20/25 cm x 40, 20 cm）, and artificial transplanting with equal row spacing （20/25 cm x 30 cm） was set as the control. The three fer- tilization modes were applying for one, two and three times. The flowering stage and panicle-spikelet structure of the male parent were investigated. The results showed that the effects of mechanized transplanting and fertilization mode were little on the duration from seeding to heading; the panicles and spikelets of the three male parents were significantly increased by mechanized transplanting. The tiller number was increased by mechanized transplanting and fertilizing for two and three times. Wide and narrow spacing by machine planting and fertilizing for three times were suitable for Huazhan, which significantly increased the number of spikelets per unit area. Furthermore, the number of spikelets per unit area of Shuhui 527 and R9311 were significantly increased by mechanized transplanting and fertilizing for three times.展开更多
Rong 18A is an Indica three-line sterile line bred with M5B×D Xing B, and has the characteristics of stable sterility, high outcrossing rate, good combining ability and good quality. With Rong 18A as an experimen...Rong 18A is an Indica three-line sterile line bred with M5B×D Xing B, and has the characteristics of stable sterility, high outcrossing rate, good combining ability and good quality. With Rong 18A as an experimental material and Ⅱ-32A, Jin 23A and Gang46 A as the CK materials, a seed setting rate estimation method by daily pollination was used for measuring its stigma vigor, to comparatively analyze the decreasing rates and lasting time of stigma vigor of various materials under natural condition. According to experimental results and combining with field breeding practice, the application of stigma vigor of sterile lines on hybrid rice seed production was discussed.展开更多
Rong 18A, bred by Crop Research Institute, Chengdu Academy of Agri- culture and Forestry Sciences is a new blast-highly resistant and high-combining ability hybrid rice sterile line. It is currently one of the male st...Rong 18A, bred by Crop Research Institute, Chengdu Academy of Agri- culture and Forestry Sciences is a new blast-highly resistant and high-combining ability hybrid rice sterile line. It is currently one of the male sterile lines in Sichuan Province which combine well high grain quality and rice blast resistance. More than 20 combinations of Rong 18A have passed the national and provincial variety iden- tification. Combined with the climate conditions in Chengdu, the key points of high- yielding seed production techniques for Rong18A are analyzed and summarized in this paper.展开更多
According to seed production of Yanliangyou 888, a two-line hybrid rice variety, the research reviewed seed production characters, as follows： to improve outcrossing rate and spike size provided sufficient spikes of ...According to seed production of Yanliangyou 888, a two-line hybrid rice variety, the research reviewed seed production characters, as follows： to improve outcrossing rate and spike size provided sufficient spikes of female/male parents. The seed production techniques include scientific arrangement of seeding interval, cultivating strong multi-tiller seedlings, scientific arrangement of row ratio of inter- cropping with adequate basic seedlings, scientific water and fertilizer management, improving outcrossing rate by synthesis measures, disease/insect control, and rein- forcing production management.展开更多
Yanliangyou 2208, bred by the Jiangsu Institute of Agricultural Sciences in Coastal Areas, is a two-line indica hybrid rice combination characterized with strong heterosis, moderate maturity, wide adaptability, good s...Yanliangyou 2208, bred by the Jiangsu Institute of Agricultural Sciences in Coastal Areas, is a two-line indica hybrid rice combination characterized with strong heterosis, moderate maturity, wide adaptability, good stability and disease resistance. It was identified as a new variety by the National Crop Variety Approval Committee in 2013. According to the characteristics of parents of Yanliangyou 2208 and com- bined with many years of seed production experience, high-yielding seed production techniques of Yanliangyou 2208 are summed up in this paper.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
In 2012-2015, under the conditions of different natural wind speeds, the single-rotor agricultural unmanned aerial vehicle was used for the supplementary pollination during seed production of 10 hybrid combinations wi...In 2012-2015, under the conditions of different natural wind speeds, the single-rotor agricultural unmanned aerial vehicle was used for the supplementary pollination during seed production of 10 hybrid combinations with big parental row ratios in the hybrid rice seed production bases of Hunan, Hainan and Guangdong Province, and the pollination effects were studied through the investigation of pollen density in the field, outcrossing seeding rate of female parent and seed production yield. The results showed that under the parental row ratio of 6：（40-60）, the seed setting rate and yields of the supplementary pollination by single-rotor agricultural UAV could reach and even higher than those of artificial pollination, indicating the single-rotor agricultural UAV could be used in supplementary pollination for hybdd rice seed production, which could promote the whole-process mechanization of seed production.展开更多
We evaluated seed production in a first-gener- ation orchard of Chinese pine （Pinus tabuliformis） during the crucial transition period from first generation to advanced generations. Clones varied significantly in al...We evaluated seed production in a first-gener- ation orchard of Chinese pine （Pinus tabuliformis） during the crucial transition period from first generation to advanced generations. Clones varied significantly in all traits related to seed production. Repeatability of these traits ranged from 0 to 0.96. Seed production per ramet （SPPR）, seed producing index （SPI）, the number of relative female strobili （RFS）, the number of scales, and the num- ber of ineffective scales had comparatively high repeata- bility at 0.86, 0.87, 0.89, 0.96, and 0.91, respectively. Correlation analysis showed that SPPR was greatly influenced by RFS and by the number of full seeds per cone. Finally, we showed that SPI was the best predictor of the seed-producing ability of clones. Our findings will assist seed orchard managers in effectively predicting and improving seed production of Chinese pine seed orchards.展开更多
Neptunea cumingii is an important nutrition-rich economic species in China.Juveniles of N.cumingii suff er from high mortality at low temperatures,which has proved a limiting factor in raising seedlings in artifi cial...Neptunea cumingii is an important nutrition-rich economic species in China.Juveniles of N.cumingii suff er from high mortality at low temperatures,which has proved a limiting factor in raising seedlings in artifi cial habitats.Previous research has shown that N.cumingii displays aggregation behavior in response to adverse environmental changes.Therefore,we determined the eff ects of temperature,food,size of juvenile snails,substratum type,and density of juvenile snails on the aggregation behavior of N.cumingii.Results show that,at a low(4°C)or a high(22°C)temperature,juvenile snails adjusted to the inhospitable environment by exhibiting increased aggregation behavior.However,their aggregation behaviors diff ered at these two temperatures.There was no signifi cant diff erence in the aggregation rate,but the typical aggregation size was larger at 4°C than at 22°C.At 10°C or 16°C,aggregation behavior of juvenile snails reduced.Aggregation increased in the satiation treatment at 10°C and 16°C.Small-sized juveniles tended to have higher aggregation rates(92.22%)and a larger typical aggregation size.More juveniles were distributed in the bottom of shaded substrata.A larger typical aggregation size or higher density signifi cantly reduced the mortality of juvenile snails at a low temperature(4°C).These results broaden our understanding of gastropod aggregation behavior and can be used to develop and improve commercial breeding strategies and resource recovery for N.cumingii.展开更多
By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defi...By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defined as 2℃. During the sensitive period of fertility, characters of panicle height and canopy structure of TGMS rice, Pei＇ai64S, were measured. Results showed that temperature changes caused by irrigation in fields were below 40 cm of rice plant, and heating effect was significant at 20 cm when the temperature was increased by 3.1 ℃. For the present study, the following irrigation techniques were put forth： the water depth of 15-20 cm, current water used, irrigating after 17：00 and bailing at 10：00 in sunny or cloudy weather, irrigating on whole day, in shady or rainy weather, increasing inflows and outflows in large fields. In the present experiment, pollen fertility and self-fertilized seed setting rate accepted that the techniques were feasible and effective for against lower temperature and safeguarding seed production of two-line hybrid rice.展开更多
Bhutan is a small landlocked country located in the eastern Himalayas. Over 69% of the population is engaged in agriculture. Rice, maize, wheat, barley, buckwheat and millets are the major cereal crops cultivated. Ric...Bhutan is a small landlocked country located in the eastern Himalayas. Over 69% of the population is engaged in agriculture. Rice, maize, wheat, barley, buckwheat and millets are the major cereal crops cultivated. Rice is the most preferred food crop of the Bhutanese. Maize is a primary food crop after rice and it ranks first among food crops in production. The cultivation ranges from less than 300 m asl （metres above sea level） nearly up to 2,800 m asl. In 2007, a new, extremely serious problem of GLS （gray leaf spot） in maize that was previously never reported in Bhutan was confirmed. This disease spread rapidly in the highland maize growing areas causing production losses of over 50% to 70%. All the maize varieties cultivated in the country were found to be highly susceptible to the disease. In order to contain this devastating disease, the national maize program drew short and long term strategies with the help of a CIMMYT Expert. As an immediate short term action to contain GLS, systemic fungicide Tilt 25 EC （active ingredient propiconazole） was supplied free of cost to the farmers. A longer term strategy pursued was the introduction, e＇valuation and selection of GLS tolerant genotypes for the highland ecosystem. Over 100 GLS tolerant genotypes vcere introduced from CIMMYT Colombia, Mexico, Zimbabwe and Nepal. These materials were initially evaluated in a disease hotspot sites and then further tested in multi-location trials in GLS affected areas across the country. Farmers were engaged for Participatory Variety Selection by organizing farmer＇s field days at the trial sites. Finally, in 2011 considering the need of GLS tolerant varieties for farmers, two GLS tolerant genotypes ICAV305 and S03TLYQAB05 were provisionally released. In the 2011 season, these two provisionally released genotypes were put under large scale demonstration in the GLS affected areas in nine districts across the country. In 2012, the two genotypes were formally released by the Technology Release Committee of the Ministry of Agriculture and Forest. Rapid seed increase of the new varieties was initiated through farmers from Community Based Seed Production groups and so far 75% seed replacement of GLS affected farmers has been accomplished.展开更多
Pollen limitation of plant reproduction occurs across Angiosperms, particularly those in patched habitats We investigated the, relationship between pollen limitation and patch variables （patch size, visitation freque...Pollen limitation of plant reproduction occurs across Angiosperms, particularly those in patched habitats We investigated the, relationship between pollen limitation and patch variables （patch size, visitation frequency） in the desert plant Hedysarum scoparium （Fabaceae）, which is an important xerophyte in the arid and semi-arid regions of Northwest China and can grow well as a pioneer plant in shifting sand dunes. We observed insect visitation to H. scoparium over two flowering seasons and estimated pollen limitation using fruit set and seed production. Our results indicate that fruit set and seed production increased significantly with pollen supplementation compared with open pollination. Hedysarum scoparium was pollinated by over 8 species of bees, with 88.4% of visits made by introduced honeybees （Apis mellifera）. Bee visitation varied significantly among the patches of habitats, but not associated with patch size of habitat. In general, pollen limitation occurred more strongly during fruit set than during seed production. The patches that received higher rates of pollinator visits were less pollen limited for fruit set. Pollen limitation for seed production, however, was not associated with pollinator visitation frequency. We conclude that pollen limitation in H. scoparium was caused by more than one reason, not just pollinator visits.展开更多
According to seed production practice, the seed production techniques for BenIiangyou 3113, a new two-Iine hybrid rice combination, were summarized. In or-der to obtaln high and stabIe yielding, the seed production of...According to seed production practice, the seed production techniques for BenIiangyou 3113, a new two-Iine hybrid rice combination, were summarized. In or-der to obtaln high and stabIe yielding, the seed production of BenIiangyou 3113 re-quires appropriate site seIection, rational sowing period, rational ratio between parental Iines, enhanced water and fertiIizer management, appropriate Ieaf cutting, strict weeding, good artificial poI ination and good pests and diseases controI.展开更多
In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents ...In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents and application amount of nitrogen fertilizer on hybrid wheat seed production and its component factors. The results showed that the seed production increased with the increase in the number of female parent row. When the row ratio of male and female parents was 2 ∶ 6,the seed production was 3 683. 8 kg/ha; when the application amount of nitrogen fertilization was 50 kg/ha,the seed production was 3 649. 4 kg/ha; the interaction between the row ratio of male and female parents and the application amount of nitrogen fertilizer indicated that when the row ratio of male and female parents was 2∶ 6 and the application amount of nitrogen fertilizer was 300 kg/ha,the seed production reached the highest( 4160. 6 kg/ha). The row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the component factors of seed production,including the number of grains per spike,spike weight and setting percentage. When the row ratio of male and female parents was 2∶ 5,the number of grains per spike,spike weight and setting percentage were the highest at 26. 7 grains,1. 12 g,and 62. 6% respectively; when application amount of nitrogen fertilizer was 450 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 26. 0 grains,1. 08 g,and59. 2% respectively; the interaction of row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the number of grains per spike,spike weight and setting percentage; when the row ratio of male and female parents was 2∶ 5 and the application amount of nitrogen fertilizer was 300 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 29. 6grains,1. 24 g,and 71. 6% respectively. The number of grains per spike is the largest component factor for seed production. Increasing the number of grains per spike can increase the seed production. According to the effects of row ratio of male and female parents and application amount of nitrogen fertilizer on the component factors of seed production,the optimal condition was 2∶ 5-2∶ 6 for row ratio of male and female parents and 300-450 kg/ha for application amount of nitrogen fertilizer.展开更多
基金Supported by Science and Technology Innovation Team of Anhui Academy of Agricultural Sciences(15C0108)Subject Construction Project of Anhui Academy of Agricultural Sciences(14A0102)Science and Technology Support Program of Ministry of Science and Technology(2012BAD07B01-3)~~
文摘Hybrid rice Xinhunyou No. 6 could be cultivated by mixing male and fe- male parents and performing seedling raising followed by transplanting, mechanical planting or mechanical direct seeding according to the production methods of com- mercial rice. During flowering stage, leaf cutting, application of ＂920＂ and pollination were conducted; after pollination, bentazon with a certain concentration was sprayed to kill the male parent; and the hybrid rice was harvested mechanically. Before storage, color separation was performed to remove little remaining male parent, thereby achieving whole-process mechanization of hybrid rice seed production. This study introduced mechanized seed production of Xinhunyou No. 6 through mixed- seeding from the aspects including mechanical direct seeding, seeding raising fol- lowed by transplanting and mechanical planting.
文摘[Objectives]Current hybrid rice seed production mechanization and a new kind of hybrid rice seed production mechanization using Bentazone sensitive lethal genes for mechanized seed production technology are introduced in this paper.[Method]Sensitive Restorer Bentazone lethal dose of filtering,parental and seed weight are bred combinations of several aspects of the system described,and presented mechanized seed technology new research directions.[Results]The method of using Bentazone sensitive lethal genes for mechanized seed production technology is feasible,economic,seed production and combination advantages.[Conclusions] Using Bentazone sensitive lethal genes for mechanized seed production technology is the new study direction of mechanic production.
基金Supported by "11thFive-Year" Crop Breeding Research of SichuanProvince "11thFive-Year" Joint Breeding Research Project Fun-ding of Sichuan Province.~~
文摘[Objective] The aim was to study the reproduction of the three-line genic male sterile （GMS） lineparent Mian7MB-1 （B. NapusL.） and the seed production of F1 through somatic tissue culture. [Methed] Through hybridization, a new breeding material Mian 7MB-1 in three-line genic temporary maintainer line propagated by tissue culture was used to improve the sterile plant rate of rapeseed in dual-purpose recessive GMS line, such as Mian 7AB type, S45AB type, and etc. And then the variety comparative test was performed. [Result] In order to avoid some fertility restoration phenomena occurring during the process of self-reproduction, Mian 7AB was propagated in bulk with somatic tissue culture of temporary maintainer line plant stem. The propagated temporary maintainer line seedlings were applied to the breeding and seed production of net room male sterile line parent, promoting the sterile plant rate of the male sterile line parent to 91.7% -93.5%. The male sterile line parents per hectare were enough for the seed production of hybrid F1 in 7 500 -15 000 hm^2. [ Conclusion ] Compared with the original dual-purpose GMS line, the seed production ultilizing male sterile line with high sterile plant rate greatly reduced the labor, significantly improved the seed yield, ensuring the seed quality and forming a perfect breeding and seed production system.
基金Supported by the Project for the Commercialization of Agricultural Research Findings in China(2011GB2D200007)the National High Technology Research and Development Program of China (863 Program) Planning for the Development of High-Technology Research in China(2010AA101304)the National Natural Science Foundation of China(31371714)~~
文摘The insecure problems of seed production have seriously hampered the healthy and sustainable development of two-line hybrid rice.The safety issues on seed production of two-line hybrid rice and current research situation were pointed out in this paper.The three main reasons for unsafety in seed production of twoline hybrid rice were unsuitable site selection,high critical sterility-inducing temperature and the drift of critical temperature.In this paper,strategies and measures were put forward based on many years of practice.It could minimize the risk in seed production of two-line hybrid rice by selecting dual-purpose genic male sterile line with lower critical sterility-inducing temperature and long lower temperature resistant time.Based on the climate data and climatic demands of the ＂three safe-periods＂ in seed production,a new idea for determining appropriate bases and periods for seed production was proposed by using computer technology,which solved the aimless selection of sites and periods for the seed production of two-line hybrid rice.Besides,we established a system of single plant selection and identification method and original seed propagation with cyclic cold water,which could reduce the generation number of original seed propagation in seed production and avoid the drift of critical sterility-inducing temperature.This paper improved the seed production safety in the three aspects of seed nature,seed source and seed production site.
基金Supported by the Important Science and Technology Key Project of An-hui Eleventh-five Year Plan(06003010B)the International Cooperation Program of Anhui Province(06088013)~~
文摘The seed production of male and female parent of ‘Hunzhi 1＇ contained bentazon susceptible gene was studied. The result showed that spraying 3. 375 L/hm2 48% bentazon aqua could control the self-pollinated fertilization rate below 1.0% and survival plant rate was 0. The spray of bentazon would not influence MC526 pollen vitality. Seed setting rate of female parent was not obvious different from that of control group with spraying bentazon aqua more than 3. 375 L/hm^2 from the sprouting appearing period to full heading stage. This demonstrated that bentazon aqua had no influence on seed setting rate during florescence of female parent. The weight ratio between male parent seeds and female parent seeds was 1 to 5, then seeds from parents with that weight ratio would be mixedly planted for seed production. With this weight ratio, relative proper structure of panicle and grain would be obtained ,panicle ratio was 1 to 4.3, glumous flowers ratio was 1 to 3.5. Cross seed-setting rate of female parent was 72.6% and seed production per hm^2 was 66 000 kg.
基金Supported by the National High-tech R&D Program(863 Program)(2014AA10A603)the Key Science and Technology Program during the"13thFive Year Plan"of Anhui Province(1604a0702008)+1 种基金the Special Fund for Agro-scientific Research in the Public Interest(201503130)the Project for the Team of Science and Technology Innovation of Anhui Academy of Agricultural Sciences(15C0108)~~
文摘Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The research progress on mixed sowing seed production techniques of hybrid rice was introduced from the aspects of rice resources creation, breeding, sowing seed technology research and cost benefit analysis. The production technology of the new mixed seeding combina- tion ＂Xinhunyou 6＂ was investigated, including the research and validation of benta- zon treatment period and dosage, mixing ratio of male and female parents, and the comparative test of different different sowing methods, which revealed that the mechanization technology of seed production of hybrid rice was mature and feasible and would be one of the most important development trend of technological devel- opment of hybrid rice production.
文摘In order to study the effects of mechanized transplanting and fertilization mode on population growth and development of the male parent in seed production of hybrid rice, three male parents, Huazhan, Shuhui 527 and R9311 were selected as materials. The male parents were transplanted by rice transplanter with two kinds of line spacing design, six lines with equal row spacing （20/25 cm x 30 cm） and wide and narrow spacing （20/25 cm x 40, 20 cm）, and artificial transplanting with equal row spacing （20/25 cm x 30 cm） was set as the control. The three fer- tilization modes were applying for one, two and three times. The flowering stage and panicle-spikelet structure of the male parent were investigated. The results showed that the effects of mechanized transplanting and fertilization mode were little on the duration from seeding to heading; the panicles and spikelets of the three male parents were significantly increased by mechanized transplanting. The tiller number was increased by mechanized transplanting and fertilizing for two and three times. Wide and narrow spacing by machine planting and fertilizing for three times were suitable for Huazhan, which significantly increased the number of spikelets per unit area. Furthermore, the number of spikelets per unit area of Shuhui 527 and R9311 were significantly increased by mechanized transplanting and fertilizing for three times.
文摘Rong 18A is an Indica three-line sterile line bred with M5B×D Xing B, and has the characteristics of stable sterility, high outcrossing rate, good combining ability and good quality. With Rong 18A as an experimental material and Ⅱ-32A, Jin 23A and Gang46 A as the CK materials, a seed setting rate estimation method by daily pollination was used for measuring its stigma vigor, to comparatively analyze the decreasing rates and lasting time of stigma vigor of various materials under natural condition. According to experimental results and combining with field breeding practice, the application of stigma vigor of sterile lines on hybrid rice seed production was discussed.
文摘Rong 18A, bred by Crop Research Institute, Chengdu Academy of Agri- culture and Forestry Sciences is a new blast-highly resistant and high-combining ability hybrid rice sterile line. It is currently one of the male sterile lines in Sichuan Province which combine well high grain quality and rice blast resistance. More than 20 combinations of Rong 18A have passed the national and provincial variety iden- tification. Combined with the climate conditions in Chengdu, the key points of high- yielding seed production techniques for Rong18A are analyzed and summarized in this paper.
基金Supported by National Key Technology R&D Program(BAD01B01,2015BAD01B02,2015BAD01B03)Independent Innovation Fund Project of Agricultural Science and Technology in Jiangsu Province(CX(15)1005-3-1)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA08030104-3)~~
文摘According to seed production of Yanliangyou 888, a two-line hybrid rice variety, the research reviewed seed production characters, as follows： to improve outcrossing rate and spike size provided sufficient spikes of female/male parents. The seed production techniques include scientific arrangement of seeding interval, cultivating strong multi-tiller seedlings, scientific arrangement of row ratio of inter- cropping with adequate basic seedlings, scientific water and fertilizer management, improving outcrossing rate by synthesis measures, disease/insect control, and rein- forcing production management.
文摘Yanliangyou 2208, bred by the Jiangsu Institute of Agricultural Sciences in Coastal Areas, is a two-line indica hybrid rice combination characterized with strong heterosis, moderate maturity, wide adaptability, good stability and disease resistance. It was identified as a new variety by the National Crop Variety Approval Committee in 2013. According to the characteristics of parents of Yanliangyou 2208 and com- bined with many years of seed production experience, high-yielding seed production techniques of Yanliangyou 2208 are summed up in this paper.
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 the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2014BAD06B07)the Rice Industry Technology System of Hunan Province~~
文摘In 2012-2015, under the conditions of different natural wind speeds, the single-rotor agricultural unmanned aerial vehicle was used for the supplementary pollination during seed production of 10 hybrid combinations with big parental row ratios in the hybrid rice seed production bases of Hunan, Hainan and Guangdong Province, and the pollination effects were studied through the investigation of pollen density in the field, outcrossing seeding rate of female parent and seed production yield. The results showed that under the parental row ratio of 6：（40-60）, the seed setting rate and yields of the supplementary pollination by single-rotor agricultural UAV could reach and even higher than those of artificial pollination, indicating the single-rotor agricultural UAV could be used in supplementary pollination for hybdd rice seed production, which could promote the whole-process mechanization of seed production.
基金supported by ‘‘the Fundamental Research Funds for the Central Universities(No.2015ZCQ-SW-02)’’ and ‘‘Special Fund for Forestry Scientific Research in the Public Interest(No.201104022)’’
文摘We evaluated seed production in a first-gener- ation orchard of Chinese pine （Pinus tabuliformis） during the crucial transition period from first generation to advanced generations. Clones varied significantly in all traits related to seed production. Repeatability of these traits ranged from 0 to 0.96. Seed production per ramet （SPPR）, seed producing index （SPI）, the number of relative female strobili （RFS）, the number of scales, and the num- ber of ineffective scales had comparatively high repeata- bility at 0.86, 0.87, 0.89, 0.96, and 0.91, respectively. Correlation analysis showed that SPPR was greatly influenced by RFS and by the number of full seeds per cone. Finally, we showed that SPI was the best predictor of the seed-producing ability of clones. Our findings will assist seed orchard managers in effectively predicting and improving seed production of Chinese pine seed orchards.
基金Supported by the National Key R&D Program of China(No.2019YFD0900800)the fund earmarked for the Modern Agro-industry Technology Research System(No.CARS-49)+5 种基金the Major Scientifi c and Technological Innovation Project of Shandong Provincial Key Research and Development Program(No.2019JZZY020708)the Industry Leading Talents Project of Taishan Scholars(to ZHANG Tao),the Double-Hundred Blue Industry Leader Team of Yantai(to ZHANG Tao)the Construction Technology and Demonstration Application of Dandong Characteristic Beach Type Marine Ranch(No.KFJ-STS-QYZD-189)the Shandong Peninsula Coastal Area Ecological Simulation Test Project:Marine Ranch Resource Evaluation and Sustainable Utilization Model ResearchNSFC-Shandong Joint Fund for Marine Science Research Centers(No.U1406403)the Creative Team Project of the Laboratory for Marine Ecology and Environmental Science,Qingdao National Laboratory for Marine Science and Technology(No.LMEES-CTSP-2018-1)。
文摘Neptunea cumingii is an important nutrition-rich economic species in China.Juveniles of N.cumingii suff er from high mortality at low temperatures,which has proved a limiting factor in raising seedlings in artifi cial habitats.Previous research has shown that N.cumingii displays aggregation behavior in response to adverse environmental changes.Therefore,we determined the eff ects of temperature,food,size of juvenile snails,substratum type,and density of juvenile snails on the aggregation behavior of N.cumingii.Results show that,at a low(4°C)or a high(22°C)temperature,juvenile snails adjusted to the inhospitable environment by exhibiting increased aggregation behavior.However,their aggregation behaviors diff ered at these two temperatures.There was no signifi cant diff erence in the aggregation rate,but the typical aggregation size was larger at 4°C than at 22°C.At 10°C or 16°C,aggregation behavior of juvenile snails reduced.Aggregation increased in the satiation treatment at 10°C and 16°C.Small-sized juveniles tended to have higher aggregation rates(92.22%)and a larger typical aggregation size.More juveniles were distributed in the bottom of shaded substrata.A larger typical aggregation size or higher density signifi cantly reduced the mortality of juvenile snails at a low temperature(4°C).These results broaden our understanding of gastropod aggregation behavior and can be used to develop and improve commercial breeding strategies and resource recovery for N.cumingii.
基金The research was supported by the National Natural Science Foundation of China （30370830）.
文摘By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defined as 2℃. During the sensitive period of fertility, characters of panicle height and canopy structure of TGMS rice, Pei＇ai64S, were measured. Results showed that temperature changes caused by irrigation in fields were below 40 cm of rice plant, and heating effect was significant at 20 cm when the temperature was increased by 3.1 ℃. For the present study, the following irrigation techniques were put forth： the water depth of 15-20 cm, current water used, irrigating after 17：00 and bailing at 10：00 in sunny or cloudy weather, irrigating on whole day, in shady or rainy weather, increasing inflows and outflows in large fields. In the present experiment, pollen fertility and self-fertilized seed setting rate accepted that the techniques were feasible and effective for against lower temperature and safeguarding seed production of two-line hybrid rice.
文摘Bhutan is a small landlocked country located in the eastern Himalayas. Over 69% of the population is engaged in agriculture. Rice, maize, wheat, barley, buckwheat and millets are the major cereal crops cultivated. Rice is the most preferred food crop of the Bhutanese. Maize is a primary food crop after rice and it ranks first among food crops in production. The cultivation ranges from less than 300 m asl （metres above sea level） nearly up to 2,800 m asl. In 2007, a new, extremely serious problem of GLS （gray leaf spot） in maize that was previously never reported in Bhutan was confirmed. This disease spread rapidly in the highland maize growing areas causing production losses of over 50% to 70%. All the maize varieties cultivated in the country were found to be highly susceptible to the disease. In order to contain this devastating disease, the national maize program drew short and long term strategies with the help of a CIMMYT Expert. As an immediate short term action to contain GLS, systemic fungicide Tilt 25 EC （active ingredient propiconazole） was supplied free of cost to the farmers. A longer term strategy pursued was the introduction, e＇valuation and selection of GLS tolerant genotypes for the highland ecosystem. Over 100 GLS tolerant genotypes vcere introduced from CIMMYT Colombia, Mexico, Zimbabwe and Nepal. These materials were initially evaluated in a disease hotspot sites and then further tested in multi-location trials in GLS affected areas across the country. Farmers were engaged for Participatory Variety Selection by organizing farmer＇s field days at the trial sites. Finally, in 2011 considering the need of GLS tolerant varieties for farmers, two GLS tolerant genotypes ICAV305 and S03TLYQAB05 were provisionally released. In the 2011 season, these two provisionally released genotypes were put under large scale demonstration in the GLS affected areas in nine districts across the country. In 2012, the two genotypes were formally released by the Technology Release Committee of the Ministry of Agriculture and Forest. Rapid seed increase of the new varieties was initiated through farmers from Community Based Seed Production groups and so far 75% seed replacement of GLS affected farmers has been accomplished.
基金funded by the National Basic Research Program of China (2009CB421303)
文摘Pollen limitation of plant reproduction occurs across Angiosperms, particularly those in patched habitats We investigated the, relationship between pollen limitation and patch variables （patch size, visitation frequency） in the desert plant Hedysarum scoparium （Fabaceae）, which is an important xerophyte in the arid and semi-arid regions of Northwest China and can grow well as a pioneer plant in shifting sand dunes. We observed insect visitation to H. scoparium over two flowering seasons and estimated pollen limitation using fruit set and seed production. Our results indicate that fruit set and seed production increased significantly with pollen supplementation compared with open pollination. Hedysarum scoparium was pollinated by over 8 species of bees, with 88.4% of visits made by introduced honeybees （Apis mellifera）. Bee visitation varied significantly among the patches of habitats, but not associated with patch size of habitat. In general, pollen limitation occurred more strongly during fruit set than during seed production. The patches that received higher rates of pollinator visits were less pollen limited for fruit set. Pollen limitation for seed production, however, was not associated with pollinator visitation frequency. We conclude that pollen limitation in H. scoparium was caused by more than one reason, not just pollinator visits.
基金Supported by Major Projects of Seed Innovation Program in Chongqing City(CSTC2012ggc80002)~~
文摘According to seed production practice, the seed production techniques for BenIiangyou 3113, a new two-Iine hybrid rice combination, were summarized. In or-der to obtaln high and stabIe yielding, the seed production of BenIiangyou 3113 re-quires appropriate site seIection, rational sowing period, rational ratio between parental Iines, enhanced water and fertiIizer management, appropriate Ieaf cutting, strict weeding, good artificial poI ination and good pests and diseases controI.
基金Supported by State Key Research and Development Program of Ministry of Science and Technology(2016YFD0101603)Fundamental Research Funds for the Central Universities in 2016(XDJK2016A020)
文摘In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents and application amount of nitrogen fertilizer on hybrid wheat seed production and its component factors. The results showed that the seed production increased with the increase in the number of female parent row. When the row ratio of male and female parents was 2 ∶ 6,the seed production was 3 683. 8 kg/ha; when the application amount of nitrogen fertilization was 50 kg/ha,the seed production was 3 649. 4 kg/ha; the interaction between the row ratio of male and female parents and the application amount of nitrogen fertilizer indicated that when the row ratio of male and female parents was 2∶ 6 and the application amount of nitrogen fertilizer was 300 kg/ha,the seed production reached the highest( 4160. 6 kg/ha). The row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the component factors of seed production,including the number of grains per spike,spike weight and setting percentage. When the row ratio of male and female parents was 2∶ 5,the number of grains per spike,spike weight and setting percentage were the highest at 26. 7 grains,1. 12 g,and 62. 6% respectively; when application amount of nitrogen fertilizer was 450 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 26. 0 grains,1. 08 g,and59. 2% respectively; the interaction of row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the number of grains per spike,spike weight and setting percentage; when the row ratio of male and female parents was 2∶ 5 and the application amount of nitrogen fertilizer was 300 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 29. 6grains,1. 24 g,and 71. 6% respectively. The number of grains per spike is the largest component factor for seed production. Increasing the number of grains per spike can increase the seed production. According to the effects of row ratio of male and female parents and application amount of nitrogen fertilizer on the component factors of seed production,the optimal condition was 2∶ 5-2∶ 6 for row ratio of male and female parents and 300-450 kg/ha for application amount of nitrogen fertilizer.
