全球水稻生产时空变化特征分析

全球水稻生产数据分析表明,1961年至2018年全球水稻面积、单产和总产年均增幅分别为0.67%、1.65%和2.33%,受多种因素制约,近年单产和面积增长幅度变小。水稻在亚洲、非洲、美洲、欧洲和大洋洲均有种植,其中,亚洲水稻种植面积占比为87.9%,非洲占7.7%、美洲占4.0%,欧洲和大洋洲不到0.5%。近10年与上世纪60年代相比,全球水稻种植面积和总产区域间分布已发生变化,非洲水稻面积增长,亚洲水稻面积下降。1961年至2018年全球水稻总产增长因子分析表明,总产增长的60%~70%来自单产的提高,各洲水稻总产增长贡献因子存在较大差异。     

浅述2008年全球水稻生产、价格和技术

2008年,预计全球水稻总产、面积和单产分别比2007年增长2．4％,1．5％和1．0％。其中我国水稻种植面积达到2920万hm^2,预计平均单产（每667m^2产量）比2007年增加3～5kg。与2007年相比,2008年5月全球稻米价格大幅上涨,其中高档籼米、低档籼米、粳米和香米分别上涨124％、159％、40％和74％。5月份以后稻米价格总体回落,9月份高档籼米和低档籼米价格比5月份分别下降27．2％和39．1％,香米价格下降13．0％,粳米价格依然上涨29．0％。为提高水稻产量,保障全球粮食安全,全球研发和推广了水稻生产集成技术、杂交稻技术、非洲新水稻、水稻节水栽培技术、提高氮肥利用率技术、水稻强化栽培技术、水稻产量差异弥合技术和省工节本栽培技术等一系列水稻生产技术。     

我国历年水稻产量增长因素分析与今后的发展对策

本文对建国以来我国历年水稻播种面积，单产和总产变化趋势做了分析，提出了播种面积或意境单和增加对总产增长贡献百分率的计算公式，即为：１００．（比较年的播种面积（或单产）一基数年的植种面积（或单产）．１／２（比较年的单产（或面积）＋基数年的单产（或面积）／总产增加数，根据计算，分析了我国历年水稻播各面积和单产增减对总的贡献，展望了今后的情况，介绍了当前的水稻增产措施。     

湖南应充分发挥产稻大省的作用

湖南是我国产稻大省，其稻谷总产量、播种面积、稻田年单产、人均占有量等均居全国首位，但也面临着面积锐减、总产徘徊、早晚稻产量差距拉大等问题。应通过加强水稻育种与栽培的科学研究工作，稳定面积，提高单产，大力挖掘早稻增产潜力，优化早晚两季品种配组，保护和调动农民种粮的积极性等来进一步提高湖南粮食产量，发挥产稻大省的作用。     

水稻品种改良技术讲座(1)──我国的水稻生产和品种改良

水稻是我国种植面积最大、单产最高、总产最多的粮食作物，其常年种植面积和总产量分别约占全国粮食作物的30％和40％。全国约有60％的人口以稻米为主食。近年来，随着国民经济的发展，我国水稻生产也出现了一些波动，如1994年稻谷总产1759亿公斤，比1990年减产了134亿公斤，主要是因为稻作面积减少了286.7万公顷所造成，也与单产增加缓慢有关。1995年稻谷单产仅比1990年每公顷提高195kg／hm2，低于“六五”和“七五”期间的增长幅度。为此，我国已致力于从政策、投入和推广先进技术着手，稳定稻作面积和提高水稻的单位面积产量。从我国的稻…     

花生—世界利用近况

花生—世界利用近况闵　平，禹山林（山东省花生研究所，莱西２６６６０１）目前世界上有６个洲种植花生，面积最大的是亚洲和非洲。据统计，８０年代亚洲年均花生收获面积为１１７２．５万公顷，非洲为５４０．６万公顷，分别占世界总收获面积的６４．０％和２９．５％，...     

世界稻米生产、消费和贸易

稻米、小麦和玉米是世界最主要的三大粮食作物，稻子性喜温暖潮湿，从热带到温带、从平原到温度适宜的山区，只要有水皆可种植。全世界约有超过半数的人以稻米为主食，全球的稻采生产和消费主要集中在亚洲。1986年世界稻米总产4．76亿吨，其中亚洲精米产量占总产的92％、美洲占5％、非洲占2％和欧洲占1％。亚洲人口约占全球人口总数的60％，消费的稻米占世界大米消费的85％—90％，特别是亚洲的缅甸、老挝、泰国和越南消费的稻米约占这些国家粮食消费总量的90％以上。据1975年统计，亚洲人均年消费稻米94．70公斤，而同期世界年人均消费稻米…     

西南主要籼稻区水稻生产现状及进一步高产的对策

西南稻区现有稻田面积467万hm^2,区内生态条件复杂,水稻种质资源丰富,稻田耕作模式多;人多地少,种植规模小。本文对该区现有生产水平与增产潜力、生产发展趋势与限制因素以及提高水稻单产的主要对策进行了深入分析与总结,提出了充分发挥西南区水稻生产潜力,进一步稳定提高单产和总产的对策。     

湖南棉花生产发展的新阶段

近三年，湖南植棉面积、单产、总产，同步持续高速发展。年均单产增长２７．７％，达到每公顷产量１２００ｋｇ。由于单产提高而增产的占总产增长总量的６２％，年均总产增长４８．６％，实现了全省用棉自给有余，由调入省变为调出省。     

同源四倍体水稻与非洲栽培稻杂交的效果

以4份同源四倍体水稻(Oryza sativa,2n=4x=48)和4份二倍体水稻(Oryza sativa,2n=2x=24)为母本,以4份非洲栽培稻(Oryza glaberrima,2n=2x=24)为父本进行远缘杂交配组,共配制32个杂交组合。研究结果表明,非洲栽培稻分别与亚洲栽培稻中的两种倍性水平的水稻品系进行杂交均表现出一定的可交配性,生殖隔离并不很严格。然而,不同倍性的亚洲栽培稻与非洲栽培稻杂交,其结实率表现出明显的差异。二倍体水稻与非洲栽培稻不容易杂交,其结实率比较低(0．32％—1．93％),而同源四倍体水稻与非洲栽培稻较容易杂交,其结实率比较高(1．22％—8．86％,)。由此认为,利用同源四倍体水稻为母本与非洲栽培稻杂交更容易将后者的遗传物质引入亚洲栽培稻。     

Growth and Yield of New Rice for Africa (NERICAs) under Different Ecosystems and Nitrogen Levels

Abstract

Scarcity of water and N fertilizer are major constraints to rice production, particularly in developing countries where rainfed upland condition dominates. Improvement of genetic adaptability to inadequate water and N fertilizer is one option to maintain productivity in these regions. NERICAs are expected to yield higher under low input conditions, but growth and yield responses of the cultivars to different ecosystems and N levels remain unknown. The objectives of this study were to characterize the growth and yield performance of NERICAs, in comparison with selected Japanese rice cultivars. The two NERICAs (NERICA 1 and NERICA 5), two Japanese upland cultivars (Toyohatamochi and Yumenohatamochi), and a Japanese lowland cultivar Hitomebore were grown under two ecosystems (irrigated lowland (IL) and rainfed upland (RU)) with two N levels (high (H) and low (L)) for two years. The cultivar difference in the aboveground dry weight and grain yield was the largest in the in RU × L plot, where the values of NERICAs were similar to those in the other plots, but the values of other cultivars were substantially reduced. Regardless of cultivar, N contents of the plants at maturity correlated significantly with the aboveground dry weight at maturity, spikelet number and grain yield per area. These results indicate that NERICAs, compared with the selected Japanese upland cultivars that were bred for drought tolerance, have a higher ability to absorb N under upland conditions, which may contribute to higher biomass production and sink formation, resulting in increased gain yield.     

The Relevance of Rice

Research into rice—the world’s most important food crop—is crucial for the development of technologies that will increase productivity for farmers who rely on rice for their livelihood. This is particularly the case throughout the developing countries of Asia and is also true for much of Latin America and, increasingly, Africa. The benefits of such increased productivity will flow through to rice-growing countries’ landless rural and urban poor, all of whom (1) are net consumers of rice and (2) spend a large proportion of their income on rice. Recent steep rises in the price of rice have amplified the need for investment in high-quality research targeted toward both the intensive irrigated rice-based systems (in which 75% of the world’s rice is grown and that must provide the rice for rapidly increasing urban populations) and the rainfed rice-based systems (many of which are characterized by unfavorable environments and extreme poverty).     

Developing rice cultivars for high-fertility upland systems in the Asian tropics

Traditionally, upland rice is grown in Asia in low-input, subsistence systems. More productive upland systems, using more fertilizer and improved varieties, are emerging in China and Philippines, and could contribute to productivity increases in rainfed environments in other countries. Here, we evaluate, on-station and on-farm, the yield under upland management of improved indica upland cultivars selected for yield under high-fertility conditions. These cultivars are compared with traditional and improved tropical japonica upland varieties, and with elite indica high-yielding varieties (HYV) developed for irrigated lowland production, to characterize the features of varieties that produce high yields in favorable upland environments. Forty-four improved and traditional varieties and experimental lines were evaluated in irrigated lowland, non-stressed upland, moderately stressed upland, severely water-stressed upland, and low-fertility upland environments in southern Luzon, Philippines. Correlations between yields in non-stress and mild-stress environments were low but positive. Some cultivars, like IR55423-01, were among the highest yielding under both conditions, indicating that high yield and moderate water-stress tolerance can be combined. Upland-selected indica varieties yielded 3.56 t ha⁻¹ in favorable upland environments on-station in southern Luzon, outperforming improved tropical japonica and irrigated varieties by 23 and 69%, respectively. They were also the highest-yielding class in infertile, acid soils. The improved upland indica cultivars are about 110 cm tall under favorable upland conditions and maintain a harvest index of nearly 0.4, or about one-third higher than other cultivar types. The best upland-adapted rice varieties produced average yields on-farm of 3.3 and 4.1 t ha⁻¹ in southern Luzon and Yunnan, respectively, outyielding traditional checks by 30–50% with moderate N application. Screening under both high-fertility, non-stress conditions and moderate reproductive-stage stress appears to be needed to develop cultivars combining high-yield potential with drought tolerance. Upland-adapted indica cultivars offer a new approach to increasing productivity and reducing risk in Asian rainfed rice systems.     

Progress in varietal improvement for increasing upland rice productivity in the tropics

Enhancing rice yield in upland rice systems through genetic improvement remains a major challenge in the tropics. This review aims to provide the trends on upland rice cultivation over the last 30 years and recent distribution of upland rice in the tropics, and to report progress in studies on genetic improvement for enhancing productivity in Africa, Asia, and Latin America. While upland rice cultivation area has reduced in Asia and Latin America over the last 30 years, the area in Africa has increased. The current share of upland rice area in total rice area is related to rainfall and gross national income per capita, especially in Africa, and higher share is associated with lower rice self-sufficiency at national level. Breeding programs in Asia and Latin America have developed high-yielding varieties using indica materials as parents. In Africa, New Rice for Africa (NERICA) varieties were developed from crosses between improved tropical japonica and Oryza glaberrima. However, recent studies report that there is scope for improving existing NERICA using upland indica materials from Asia. In highlands of Africa, there are ongoing breeding programs using japonica varieties, such as the Nepalese Chhomrong Dhan. Key important plant traits used in the breeding programs are not largely different across regions, especially intermediate plant height and tillering capacity (which may be related to weed-suppressive ability), and high harvest index. In conclusion, we propose an international network for breeding upland rice with accelerating seed exchange across regions that could enhance upland rice productivity through genetic improvement.     

粳型陆稻恢复系资源的筛选及其利用研究

对不同粳稻不育系与146个粳型陆稻品种测交所得21 7个组合的结实率观测结果表明,测交组合的平均结实率为36.3%,其中24个组合(占11.1%) 的结实率＞70%,说明与普通粳稻不同,粳型陆稻品种中存在丰富的恢复系资源.与不同地区的陆稻品种测交,不同质源的不育系的可恢性有一定差别.对7个组合的产量、8个组合的米质(糙米率和垩白粒率)与其相应的父本进行比较的结果表明,测交组合产量优势明显,且米质也得到显著改善.另对2个测交组合进行旱作种植,不仅比大面积应用的杂交粳稻黎优5 7大幅增产(增幅达93.2%),而且比陆稻父本也增产;在旱种和水田条件下产量接近黎优 57的水平.如对亲本进一步筛选和改良,有望育成水旱兼用、在不同栽培条件下均能显著增产的水陆稻杂交种,在旱涝并存地区具有广阔的应用前景.     

Rice yield and productivity gaps in irrigated systems of the forest zone of Côte d'Ivoire

Much of the rapidly growing demand for rice in West Africa will be met from increased production in irrigated lowlands, which cover about 12% of the regional rice-growing area. A large potential for expansion of irrigated areas exists particularly in the inland valleys of the humid forest zone. Current production is characterized by large variability in productivity, management practices and production constraints. Quantifying the variability in rice yield and identifying the determining factors are prerequisites to the development of site-specific recommendations and to improved targeting of technologies. Diagnostic on-farm trials were conducted on 64 irrigated lowland fields in the humid forest zone of southern Côte d'Ivoire, in 1995–1996. This was a part of the regional gradient study of irrigated systems from the desert margin to the humid forest zone. Cropping calendars, field operations and input use were monitored. Weed biomass, rice N uptake, and grain yield were determined in farmers' fields as well as in super-imposed, researcher-managed subplots (clean weeding, no N control, and mineral fertilizer N application). Rice yield potential was simulated by using the Oryza-S crop growth model. Yield losses were attributed to management factors based on performance of rice in researcher-managed subplots (management-related yield gap) and by multiple regression with management options. Grain yields varied between 0.2 and 7.3 Mg ha⁻¹ with mean yields of 3.2 in partially and 4.2 Mg ha⁻¹ in fully irrigated systems, 44% and 57% of the potential yield of 7.3 Mg ha⁻¹, respectively. Age of seedlings at transplanting, timeliness of operations and application of P fertilizer were correlated to yield and explained 60% of the observed variability. Grain yield was correlated with N uptake (r² = 0.93^***) but not with N application rate. Split application of mineral fertilizer N was associated with a 0.48 Mg ha⁻¹ yield increase (p = 0.002), regardless of the quantity applied. Additional weeding increased yield only in systems with imperfect irrigation. Weed biomass was reduced with improved water control and it increased with age of seedlings at transplanting, and was higher in direct-seeded than in transplanted rice. Echinochloa spp. were the most common weeds in fully irrigated systems and Panicum laxum was more common in the imperfectly irrigated fields. While improved water management was associated with substantial rice yield increases (1.16 Mg ha⁻¹), the timeliness of transplanting, weeding and N fertilization appears to be the key to increased rice yields in the forest zone of West Africa.     

Influence of crop establishment methods on yield,economics and water productivity of rice cultivars under upland and lowland production ecologies of Eastern Indo-Gangetic Plains

A field study on assessment of crop establishment methods on yield, economics and water productivity of rice cultivars under upland and lowland production ecologies was conducted during wet seasons (June–November) of 2012 and 2013 in Eastern Indo-Gangetic Plains of India. The experiment was laid-out in a split-plot design (SPD) and replicated four times. The main-plot treatments included three crop establishment methods, viz. dry direct-seeded rice (DSR), system of rice intensification (SRI) and puddled transplanted rice (PTR). In sub-plots, five rice cultivars of different groups like aromatic (Improved Pusa Basmati 1 and Pusa Sugandh 5), inbreds (PNR 381 and Pusa 834) and hybrid (Arize 6444) were taken for their evaluations. These two sets of treatments were laid-out simultaneously in two production ecologies, upland and lowland during both years. In general, lowland ecology was found favourable for rice growth and yield and resulted in 13.2% higher grain yield as compared to upland ecology. Rice grown with SRI method produced 19.4 and 7.0% higher grain yield in 2012 and 20.6 and 7.1% higher in 2013, over DSR and PTR. However, PTR yielded 13.1 and 14.5% higher grain over DSR during 2012 and 2013, respectively. On an average, Arize 6444 produced 26.4, 26.9, 28.9 and 54.7% higher grain yield as compared to PS 5, P 834, PNR 381 and IPB1, respectively. Further, the interaction of production ecologies × crop establishment methods revealed that, in upland ecology, SRI recorded significantly higher grain yield as compared to PTR and DSR, but in lowland, grain yield resulting from SRI was similar to the yield obtained with PTR and significantly higher than DSR. The latter two methods (PTR and DSR) yielded alike in lowland ecology in both study years. The production ecologies × crop establishment methods × cultivars interaction on grain yield showed that the growing of Arize 6444 cultivar using SRI method in upland ecology resulted in the higher grain yield (8.87 t/ha). But the cost of production was also highest in SRI followed by PTR and DSR across production ecologies and cultivars. Cultivation of hybrid (Arize 6444) involved higher cost of production than all other cultivars. Irrespective of crop establishment methods and cultivars, gross returns, net returns and B:C ratio were significantly higher in lowland compared to upland ecology. Owing to higher grain yield, SRI method fetched significantly higher gross returns and net returns over PTR and DSR. Average increase in net return with Arize 6444 was 68.8, 41.0, 37.7 and 33.1% over IPB 1, PNR 381, P 834 and PS 5, respectively. There was a saving of 30.7% water in SRI and 19.9% in DSR over PTR under upland ecology. Similarly in lowland ecology, water saving of 30.2% was observed in SRI and 21.2% in DSR over PTR. Due to higher yield and saving on water, SRI returned significantly higher total water productivity (TWP) (5.9 kg/ha-mm) as compared to DSR (3.5 kg/ha-mm) and PTR (3.6 kg/ha-mm) under upland ecology. In lowland ecology, also SRI (6.2 kg/ha-mm) resulted in higher TWP as compared to other two methods. However, DSR gave significantly higher TWP as compared to PTR. Among cultivars, hybrid Arize 6444 recorded the highest TWP in both upland and lowland production ecologies across crop establishment methods. Hence, growing of hybrid Arize 6444 with SRI method can enhance rice productivity and water-use efficiency in lowland and upland production ecologies of Eastern Indo-Gangetic Plains and in other similar regions.     

The Future of Cereal Yields and Prices: Implications for Research and Policy

SUMMARY

Crop yields experienced significant increases in much of the world over the last 30 years, in large part due to investment in agricultural research, irrigation, and rural infrastructure. However, recent declines in yield growth are major causes of concern for future food security. Especially in Asia and sub-Saharan Africa the future prospects for food production are problematic. Both regions must meet strong growth in food demand–driven mainly by income growth in Asia and by population growth in sub-Saharan Africa. The production challenges in the two regions are fundamentally different: much of Asia is facing post-Green Revolution challenges of how to sustain crop yield growth following widespread adoption of modern varieties while dealing with environmental degradation in some high intensity crop production systems. Sub-Saharan Africa has yet to experience a Green Revolution, and must boost crop yield growth in the face of less favorable agroclimatic environments than in Green Revolution breadbaskets of Asia. In this paper, we review the past and possible future developments in yield growth in Asia and sub-Saharan Africa, the possible causes of the current yield growth problems and the management challenges both regions face to overcome them.     

Simulation model of rainfed rice production on sloping land in northeast Thailand

In northeast Thailand, the rapid expansion of rainfed paddy fields has decreased the stability of rice production. This paper describes a model that computes rice production on the basis of the hydrologic conditions of rainfed paddy fields on hill slopes. The model well expressed the hydrologic processes, rice yield, and production at the study site. We simulated rice production as uphill paddy plots are abandoned, increasing catchment area, under various rainfall conditions. The simulation showed that rice yield and stability increase as uphill plots are abandoned, although the total rice production decreases. Thus, the effect of catchment size on rice production in each plot was quantified. The model proved to be useful for analyzing rainfed rice production under various land and water conditions.