Simulating Responses of Rice Yield and Nitrogen Fates to Ground Cover Rice Production System under Different Types of Precipitation Years

The Ground Cover Rice Production System(GCRPS)has considerable potential for securing rice production in hilly areas.However,its impact on yields and nitrogen(N)fates remains uncertain under varying rainfall conditions.A two-year field experiment(2021–2022)was conducted in Ziyang,Sichuan Province,located in the hilly areas of Southwest China.The experiment included two cultivation methods:conventional flooding paddy(Paddy,W1)and GCRPS(W2).These methods were combined with three N management practices:N1(no-N fertilizer),N2(135 kg/hm^(2)urea as a base fertilizer in both W1 and W2),and N3(135 kg/hm^(2)urea with split application for W1 and 67.5 kg/hm^(2)urea and chicken manure separately for W2).The WHCNS(Soil Water Heat Carbon Nitrogen Simulator)model was calibrated and validated to simulate ponding water depth,soil water storage,soil mineral N content,leaf area index,aboveground dry matter,crop N uptake,and rice yield.Subsequently,this model was used to simulate the responses of rice yield and N fates to GCRPS under different types of precipitation years using meteorological data from 1980 to 2018.The results indicated that the WHCNS model performed well in simulating crop growth and N fates for both Paddy and GCRPS.Compared with Paddy,GCRPS reduced N leaching(35.1%–54.9%),ammonia volatilization(0.7%–13.6%),N runoff(71.1%–83.5%),denitrification(3.8%–6.7%),and total N loss(33.8%–56.9%)for all precipitation year types.However,GCRPS reduced crop N uptake and yield during wet years,while increasing crop N uptake and yield during dry and normal years.Fertilizer application reduced the stability and sustainability of rice yield in wet years,but increased the stability and sustainability of rice yield in dry and normal years.In conclusion,GCRPS is more suitable for normal and dry years in the study region,leading to increased rice yield and reduced N loss.

Smart Farming for Sustainable Rice Production:An Insight into Application,Challenge,and Future Prospect

Rice has a huge impact on socio-economic growth,and ensuring its sustainability and optimal utilization is vital.This review provides an insight into the role of smart farming in enhancing rice productivity.The applications of smart farming in rice production including yield estimation,smart irrigation systems,monitoring disease and growth,and predicting rice quality and classifications are highlighted.The challenges of smart farming in sustainable rice production to enhance the understanding of researchers,policymakers,and stakeholders are discussed.Numerous efforts have been exerted to combat the issues in rice production in order to promote rice sector development.The effective implementation of smart farming in rice production has been facilitated by various technical advancements,particularly the integration of the Internet of Things and artificial intelligence.The future prospects of smart farming in transforming existing rice production practices are also elucidated.Through the utilization of smart farming,the rice industry can attain sustainable and resilient production systems that could mitigate environmental impact and safeguard food security.Thus,the rice industry holds a bright future in transforming current rice production practices into a new outlook in rice smart farming development.

Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor

Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm work.The phenomenon has notably shaped the intergenerational division of labor(IDL)within households.However,it remains to be seen how farmers adjust their rice production systems in response to the IDL.The age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the IDL.Based on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service availability.Further analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational transfer.Monetary transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL households.This study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.

Breeding and Seed Production Techniques of New Aromatic Danxiangyouzhenliang Rice Variety with Good Quality and High Yield

Danxiangyouzhenliang rice is a high-quality rice variety derived from the hybrid breeding of Danxiang 12A and Xianghuixiangmiao R133.Its unique temperature-sensitive three-line characteristics endow it with significant advantages of high and stable yield,and its rice fragrance is exquisite and its taste is delicate.Danxiangyouzhenliang rice showed good resistance to rice blast and bacterial blight.On June 10,2021,Danxiangyouzhenliang rice passed the Guangxi Crop Variety Approval(Guishendao 2021074).Danxiangyouzhenliang rice is suitable to be planted as early and late rice in southern,central and northern Guangxi.This study summarized the breeding process and high-yielding seed production techniques of Danxiangyouzhenliang rice,in order to provide useful reference for rice breeders and growers.

Analysis on Rice Production in China

The research detailed history and status quo of global grain and rice production in terms of growing area, per unit area yield and total yield and performed analysis on the role of rice production in China and world grains. It can provide useful references for researchers on rice breeding.

Study on Mechanization Hybrid Rice Seed Production Technology and Combine Breeding Advances

[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.

Current Status of Rice Production in Burundi and Its Development Strategies

Burundi, a landlocked country locked near the equator, is one of the least developed countries confirmed by the United Nations and the 60% financial revenue needs aid. Rice is the most important and extravagant food in Burundian consumption for no more than 5 kg on average per people by year. It＇s especially suitable to plant rice in Burundi because of the sufficient sunlight and rain. But the lack of new varieties, practical technology and modern service make it very difficult for rice production. According to this significant roll, the rice production has to be increased in order to satisfy the consumption needs which are now becoming higher and keep the food safe. This article mainly shows the rice ecological types, production facts and the major constraints of rice production in Burundi, and then look into the distance on how to solve the problems.

Research on the Dynamic Climatic Production Potential of Middle-season Rice in Jiangxi Province

According to the meteorological data from Meteorological Station during 1961-2007 in Jiangxi Province,using the calculation method of production potential of climate recommended by Food and Agriculture Organization(FAO),the variation trends of climatic potential productivity of mid-season rice during this period were analyzed.The results indicated a trend of yearly decline in the variation of photosynthetic and light-temperature potential productivity in Jiangxi.The changes of climatic production potential fluctuated widely.The main reasons for the above-mentioned changes in recent years included more serious air pollution,resulting in less light and decline in photosynthetic potential productivity.An increase in extreme high-temperature days inhibited the growth of mid-season rice.The uneven distribution of precipitation resulted in the volatility of climatic production potential.To ensure high and stable yield,some counter-measures should be taken,including increasing weather modification input,building water conservancy facilities,enhancing the accuracy of weather forecasts and strengthening the research on climate changes.All the methods could solve those problems so as to ensure an improvement in rice production capacity to address climate change.

Solutions to Insecurity Problems in Seed Production of Two-line Hybrid Rice

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.

A Summary of Ratoon Rice Production Technology in Southwest Ecotope of China

This paper focus on the ratoon rice, which with the features of south Chi-na paddy cultivation technology. First, the development of the technology research on ratoon rice in southwest ecotope of China was briefly reviewed. Second, the key technical measures of the ratoon rice production were described in detail. At last, the application effect of the ratoon rice production technology was described accu-rately, which based on the production practice in recent years. The purpose of this article is promoting the research and extension of the ratoon rice technology more widely in world’s main rice-producing areas, especial y in the suitable area where the light and heat resources are rich.

The Application of Bentazon Susceptible Gene on Seed Production of Hybrid Rice

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.

Research Progress on Mechanized Mixed Sowing Seed Production Technology of Hybrid Rice

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.

Analysis on Input-Output in Rice Cultivation Based on Cobb-Douglas Production Function

[Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production （CD） function was used to do the quantitative analysis on the input-output in rice production with rice growers as the objective. [Result] Considering the substitution effect of labor in- put and capital input, under the same technical conditions, the effect of increasing labor input on the rice production in per 667 m2 was negative, based on which 2 pieces of policy suggestions were put forward to promote the transfer of surplus la- bor force of rice growers and ensure the capital supply for rice production. [Conclusion] This study laid the foundation for the realization of reasonable allocation of rice production resources.

Analysis of Natural Condition,Present Situation and Potential of Rice Production Development in Angola

[Objective] The aim was to make analysis on natural condition,present situation,and potential of rice production development in Angola.[Method] Conclusion and analysis of rice development in Angola were conducted from natural condition,production status,present problem and development potential.[Result] In Angola,about 30 million hectares agricultural lands enjoy fresh water,temperature,and light resources which are requirement for rice development.Presently,however,some disadvantages have harassed the nation,such as outdated production mode and technology,small cultivated area and low level of per unit yield.In addition,about 98% of consumed rice was imported from other countries.The government has attached high importance to food production,and rice production was a priority of national investment.Per unit rice yield would achieve 7 500 kg/hm2 if Angola introduces hybrid rice species and high-yield cultivation techniques from China.[Conclusion] The research provided technical reference for enterprises or individuals ready to invest in rice development in Angola.

Effects of Mechanized Transplanting and Fertilization Mode on Population Growth and Development of Male Parent in Seed Production of Hybrid Rice

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.

High-yielding Seed Production Techniques of Disease-resistant and High-quality Hybrid Rice Sterile Line Rong 18A

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.

Production Performance and Development Strategies of Double-cropping Rice in Hunan Province

ln the research, an empirical analysis was performed on production per-formance and influential factors of rice in Changsha County and Liling City. The re-sults showed that production scale has been closely linked to age and education level of farmers. The larger scale, the higher comprehensive performance, but rele-vant efficiency tends to be lower. Sowing area and yield per unit area are major in-fluential factors of production performance of double-cropping rice, but the rest influ-ential factors are different upon production scale. Final y, developmental strategies are proposed for development of double-cropping rice.

Study on High-yielding Seed Production Technologies of Japonica Hybrid Rice

[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.

High-yielding Seed Production Techniques and Characteristics of Hybrid Rice Yanliangyou 888

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.

Seed Production Techniques of Two-line Indica Hybrid Rice Yanliangyou 2208

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.