Qinggen CHEN
Rice Science and Technology Information Center of China National Rice Research Institute,Hangzhou 310006,China
Rice,as one of the most important grain crops for survival of humanbeings,feedsmore than half of world’s population.Among rice,wheat,and maize harvested throughout the year,rice ranks second only to wheat in terms of area harvested.China is the second largest rice producer and the largest rice consumer in the world;China annually harvests 28.6 million to 30 million hm2rice,accounting for 20% of world rice planting area[2].China’s annual total yield of rice is about 200 million tons,accounting for more than 30% of world’s total rice yield and ranking first in the world.In 2014,rice planting area of the whole country was 30.309 2 million hm2,per unit area yield was 6 810 kg/hm2,and total yield reached 206.427 million tons.Both the per unit area yield and total yield created the all-time new and high(Cheng Shihua,Work Report of Chief Scientists of National Rice Industry System,2014).Increasing rice yield by every possible means is of great significance for solving China’s food securityand world’s social stability.
Rice is the most important grain crop in China,and more than 60% Chinese people take rice as staple food[3].Therefore,developing China’s rice production becomes an essential guarantee for solving China’s food security and grain ration demand[4].In rice production,the super rice developed in recent two decades plays a key and great role in ensuring China’s grain ration demand[5].
Development of super rice plays a great role in increase and safety of national food[3,5].Rapid increase of per unit area yield of super rice drives gradual increase of per unit area yield of rice;varieties of certified super rice are also increasing year by year,the extension area is increasing year by year,and the proportion of super rice area to total rice area is constantly increasing[6-7].At the same time of guaranteeing the yield of wheat and maize,how much grain yield does the development of super rice increase?How much grain does it save for cultivated area? How about the influence of super rice on increase of growers’economic income?What about the difference between southern and northern super rice production in cost and profit? On the basis of these problems,we made relevant survey,analysis,and study on northern Heilongjiang Province,southern Hunan Province,and eastern Zhejiang Province.
Super rice is the variety of rice with yield,quality,disease resistance,and anti-disaster significantly exceeding the existing rice varieties.In general,super rice refers to super high yield rice.The super rice plan,also called super high yield rice plan,was first put forward by Japan in 1980.In the following two decades,agricultural experts made effort to tackle this plan,but there was little progress;however,China’s super rice is outshining in the world[8-9].
The per unit area yield of China’s super rice in one hundred mu demonstration paddy field reached 10.5 t/hm2and 12 t/hm2of the goal of phase I and phase II respectively in the first decade of 21stcentury.In 2011,the super rice yield of one hundred mu demonstration paddy field reached 13.5 t/hm2of the goal of phase III.Later,in multipointandmulti-areademonstration paddy field,super rice yield reached the goal.In 2014,the super rice yield of a pilot paddy field reached 15.0 t/hm2of the goal of phase IV.At present,it is marching towards connecting multi-point of one hundred mu demonstration paddy field of the goal of phase IV.According to forecast of Yuan Longping,father of hybrid rice,super rice will reach the per unit area yield of 16.5 t/hm2in 2020.In 2014,the Ministry of Agriculture launched and implemented “Program of Increasing China’s Super Rice Yield to 1 000 kg/mu”.It planed to break the technology bottleneck of application of strong inter-subspecific heterosis in 5-8 years,and cultivate new super rice varieties with potential per unit area yield topping 15 000 kg/hm2.Yield target set forth in this plan is as follows:over 13.5 t/hm2for single harvest rice in upper reaches of Changjiang River and northeastern main rice production field and over 14.250 t/hm2for per unit area yield in high yield paddy field;over 13.5 t/hm2for single harvest rice in middle and lower reaches of Changjiang River and over 15.0 t/hm2for per unit area yield in high yield paddy field.
Compared with original rice varieties,super rice has higher yield and combines quality and resistance and is thus well received by farmers.In recent ten years,super-hybrid rice has been receiving close attention from scientific research,extension,and production departments in the whole country[9-10].From the perspective of research areas,it is forming the situation of dominance by three research institutions,namely,research of super hybrid indica rice and japonica rice by China National Rice Research Institute in the east,research of super japonica rice by Rice Research Institute of Shenyang Agricultural University in northeast,and research of super hybrid rice by Hunan Hybrid Rice Research Center in the central south[11].China National Rice Research Institute,as a national super rice extension expert organization,undertakes the responsibility of leading the extension of super conventional indica rice,twoline indica rice,three-line hybrid rice,and super japonica rice researched by provincial and city level academy of agriculturalsciences in the whole country.
From 2005 to 2015,118 new super rice varieties available for extension were certified by the Ministry of Agriculture.These varieties are mainly distributed in 16 main rice production provinces.Specifically,conventional japonica rice is distributed in Jiangsu,Heilongjiang,Liaoning,Jilin,Henan,and Yunnan;two-line hybrid indica rice is mainly distributed in Hunan,Hubei,Jiangsu,and Anhui;three-line hybrid rice and conventional indica rice are mainly distributed in upper,middle,and lower reaches of Changjiang River,and South China rice planting area;indica and japonica hybrid rice is distributed in Zhejiang Province;threeline japonica hybrid rice is mainly planted in medium and late-maturing rice areas of Liaoning Province to the south of Shenyang.
China’s super rice production can be divided into north and south blocks,while super rice breeding researches are mainly divided into southern super hybrid rice and northern conventional super rice.The southern super hybrid rice mainly produces long grained indica rice,suitable for planting in southern indica rice areas;the northern super rice produces oval grain rice,i.e.Northeast Rice,suitable for planting in northern rice areas and some suitable for planting in south and north connection rice areas.
The proportion ofsuperrice planting area to total rice planting area is increasing year by year.In 2007,super rice planting area accounted for 22% of total rice planting area in the whole country.The proportion reached 27%,29%,and 31% in 2012,2013,and 2014 respectively,showing an annual growth of 2%.In recent years,super rice extension area is rapidly increasing in northern area,and the growth rate of the per unit area yield is faster than southern area.
In 2010,the extension area of super rice reached 6.7 million hm2;in 2013,it reached 8.7 million hm2:1.333 3 million hm2in northeastern area,2.466 7 million hm2in middle reaches of Changjiang River,1.866 7 million hm2in lower reaches of Changjiang River,3 million hm2in southern and southwestern areas.Now,super rice is developing at an annual growth rate of 0.666 7 million hm2,and it is developing rapidly especially in Heilongjiang,Jiangxi,Hunan,and Guangxi.Over ten years,the total extension area of super rice reached 64 million hm2in the whole country,the annual extension area rose from 2.558 million hm2in 2005 to 9 million hm2in 2014,and the proportion to rice planting area increased from 8.7% to 31%.Since the research,production,and extension of super rice,China has realized increase of rice yield for 900 kg/hm2,increased the yield about 50 billion kg in total,and created economic income of 150 billion yuan[8].
In the whole country,we selected three provincesto survey:Hunan Province (a traditional large rice production province),Zhejiang Province(rice production area reducing rapidly buteconomically developed),and Heilongjiang Province (fastest growth and development of rice production area,including super rice).On the basis of survey on rice growers in Zhejiang and Hunan provinces in 2009,we entrusted local agricultural technicians of agricultural technical stations to carry out a survey on the same rice growers in 2015,and we made a field survey on rice growers in Heilongjiang Province.The survey involved 1615 households of 64 administrative villages in 24 towns of 24 counties(cities and districts)in these 3 provinces,including samples of 1015 households in 14 counties of Heilongjiang Province and 600 households in 10 counties and cities in Hunan and Zhejiang provinces.Through preliminary survey and analysis,valid samples were 1003 households in Heilongjiang Province,285 households in Hunan Province,and 280 households in Zhejiang Province,one large,medium,and small sized farm separately,3 rice processing enterprises,and 3 seed enterprises in Heilongjiang Province.
Principle for sample selection:for Zhejiang and Hunan provinces,firstly selected 5 cities with rice production area ranking top five,then,selected five counties with rice production area ranking top five in the city,randomly selected a county,divided towns into 5 groups in the sequence of rice production area,randomly selected a town in each group,selected 5 administrative villages in this town in equidistantmanner,and selected 12 households in each administrative village in equidistant manner as surveyed households in this village,finally we obtained data of 300 households in each province.According to survey results,we collected 300 samples in Hunan Province,285 samples were valid,including 153 households of super rice growers and 132 households of conventional rice growers;we collected 300 samples in Zhejiang Province,280 samples were valid,including 182 households of super rice growers and 98 households of conventional rice growers.For Heilongjiang Province,we took survey data of 1 000 households in 14 villages of 14 counties(cities)in the National Rural Fixed Observation Point system,in addition to 15 households of specialized rice growers in 3 counties and cities,we surveyed 1015 households of rice growers.Through preliminary test,there were 1 003 households of valid samples,including 532 households of super rice growers and 471 households of conventional rice growers.In total,there were 876 households of super rice growers and 701 households of conventional rice growers in three provinces.
Oursurvey mainly contained name,age,educational level,family size,and labor engaged in farming of households,name of rice variety,rice planting area,major planting variety,number of production seasons,per mu yield,per mu output value,per mu production cost,farmland rent expenses,cultivation expenses,machinery expenses,animal power and labor expenses,seed costs,fertilizer expenses,pesticide expenses,mechanical and manual transplanting expenses,mechanical and manual harvesting expenses,production management expenses,rice sales expenses,per mu labor demand,local daily wage expenses,per capita net income of local farmers,fine seed subsidy income,sales subsidy,test and demonstration expenses,local technician guiding operation mode,soil condition factors,paddy field production environmental factors,local production climate,enthusiasm of planting rice,rice planting benefit,sale operation or not,and specialized cooperatives or not.
China’s rice determines China’s grain ration security[4].In 2014,China’s rice planting area was 30.309 2 million hm2,just 2 533.33 hm2lower than 2013;the per unit area yield was 6 810 kg/hm2,93.0 kg/hm2higher than 2013 and 33.0 kg/hm2higher than the highest yield year 2012;the total yield reached 206.427 million tons,increasing about 2.815 million tons,2.191 million tons more than the highest yield year 2012,showing the all-time new and high per unit area yield and total yield(Cheng Shihua,Work Report ofChief Scientists of National Rice Industry System,December 2014).Assuming 60% people consume rice,and per capita annual consumption of rice 252 kg,calculated at per capita annual rice demand of 275 kg,the grain ration self-sufficiency ratio reached 91.63%.
Table 1 Basic data of household survey
Comparison of production cost and income between southern and northern super riceWe compared production cost and income of super rice growers in northern Heilongjiang and southern Zhejiang.The typical super rice varieties were Longjing 31 and Yongyou 12,and their production cost and income were listed in Table 2.
According to yield of super rice produced by ordinary rice growers,super rice Longjing 31 was higher than Yongyou 12.Main differences were resulted from rice varieties,soil,and climate.Generally,average yield of northern super rice was 5% -10% higher than southern super rice.In our study,the difference of super rice yield was 5.5%.
As for the sales price,actual sales price of northern rice was lower than southern rice.This is mainly because few northern rice growers sell rice to state-owned grain depot.Due to much land but few people,grain merchants will buy rice from rice growers at minimum price,and transport and sell to state-owned grain depot.Some rice growers will fail to enjoy the state minimum grain purchase price policy and consequently obtain less income.In comparison,most southern rice growers sell rice directly to grain distribution station,and the grain distribution station supplies grain sales subsidies according to provisions of state grain purchasing subsidy funds.Such price difference directly affects economic income of rice growers.
With regard to production cost and output,the total production cost and expenses for super rice are basically equal in northern and southern areas,but the per unit net output and net profit of southern area is higher than northern area.Specifically,net output value and net profit of southern rice growers is higher than northern area (6 000 yuan/hm2),and higher than the national average value(3 000 yuan/hm2),and the profit rate of cost of southern area is 30% higher than northern area and 15% higher than the national average level.
Comparison of internal factor cost difference between southern and northern super rice productionThrough the survey of rice planting in Zhejiang and Heilongjiang,we found that the total production input cost is basically equal,but the internal factors of production input are slightly different.The production input is as listed in Table 3.
Table 3 indicated that there is significant difference in internal structure between southern and northern rice growers.The difference is not significant in per unit rice production cost,while the difference in internal structure of cost is significant.For both northern and southern rice production,the basic per unit production cost is about 21 000 yuan/hm2,the northern area is slightly higher than the southern area.However,there is significant difference in cost structure,mainly manifested in seed,fertilizer,pesticide,and irrigation expenses.
There is significant difference in super hybrid japonica seed expenses between southern and northern areas.In northern area,most rice growers plant conventional rice,they can keep rice seed by themselves or buy rice seeds from seed companies(at price of 2.5 yuan/kg).For either manner,the seed cost will not exceed 375 yuan/hm2.In comparison,rice growers in southern area basically plant hybrid rice,they have to buy seed from seed companies.Seed price is constantly rising in seed companies,especially the super hybrid rice seed,the price has risen to 80 yuan/kg in some areas.
The fertilizer and pesticide cost of southern rice growers is higher than northern rice growers.Due to difference of climate and soil conditions,fertilizer and pesticide use in northern area is lower than southern area.The cost of these two items in northern area is lower than southern area for 1 770 yuan/hm2.
Rice growers in northern area have to pay higher irrigation expenses.Irrigation expense is an essential production cost for rice growers in northern area.Due to shortage of water resource,northern rice growers have to pay 1 275-1 350 yuan irrigation expenses for one hectare paddy field every crop season,accounting for 6.8% of production cost,while southern rice growers only pay 150 yuan for one hectare paddy field,accounting for 0.8% of production cost,so the difference is significant.
Land rent in northern area is higher than southern area.Due to influence of state subsidies for rice crop and northern rice is very popular with southern people,northern rice growers become highly enthusiastic to plant rice.As a result,land rent in northern area is increasing year by year.In 2014,land rent of northern rice growers exceeded southern rice growers for near 1 200 yuan/hm2.
Table 2 Product cost and profit of typical super rice varieties in southern and northern areas
The difference of operating methods leads to slight difference in costs of every process.In transplanting process,southern rice growers mainly adopt direct seedling,while northern rice growers mainly adopt auxiliary measures such as mechanical transplanting,manual carrying of seedlings,and seedling protection;production scale of southern rice growers is smaller than northern rice growers and the operating process of southern rice growers is basically semi-mechanical,while production scale of northern rice growers is large and wide,northern rice growers basically adopt mechanical operation for the whole process,and the cost is slightly different in production links,as listed in Table 3.
The profit of super rice and conventional rice in production,processing,and sales is listed in Table 4.
Comparison of profit in production,processing and salesFrom Table 4,we can see that the profit in production of 100 kg rice is lower than profit of processing and sales of 100 kg rice.Basically,rice growers’profit of producing 100 kg rice is only a half of that of processing 100 kg rice,and 2/3 of sales of 100 kg rice.The profit of super rice in production,processing,and sales is higher than that of conventional rice.In production link,the profit of super rice is 48.26% higher than conventional rice;in processing link,it is 45.36% higher;and in sales link,it is 21.62% higher.
Table 5 Spatial yield development and potential of super rice in China
Table 6 Comparison between super rice and conventional rice in the number of people they feed in the context of rice yield in 2014
Table 7 Development potential and growth contribution of super rice planting area at different stages
Rice price is a major factor determining profit of production,processing,and circulation and salesIn production link,average price of super rice is 3.21 yuan/kg,which is higher than average price of conventional rice for 16% ;in processing link,the profit of processing 100 kg super rice is higher than conventional rice for 26.68%,and super rice price is higher than conventional rice price for 28.57% ;in sales link,because the price of fine packaging rice is much higher than bagged rice,the profit of super rice is higher than conventional rice for 40% -50% on average.
Rice quality and taste are major factors influencing profit in circulation linkIn production link,rice price is a decisive factor of rice growers’profit;in processing link,the decisive factors of profit include shape of rice grain and early rice or late rice;in sales link,profit mainly comes from rice quality and taste.
Table 5 listed average national rice yield,super rice yield of 100 mu demonstration paddy field,gap of actual super rice yield,and spatial development potential of super rice over the past 10 years.
Area and yield potentialWith increase of super rice planting area and per unit area yield,the gap between average national rice yield and the yield of 100 mu super rice demonstration paddy field will be widened gradually.In 2013,the average national rice yield was only 50% of the yield of 100 mu super rice demonstration paddy field;in planting area,the super rice will exceed 12.5 million hm2in 2020,accounting for 43% of total rice planting area in China.According to increasing trend and rate of super rice planting area,the annual increase of super rice planting area will be 0.5333 million to 0.666 7 million hm2.Calculated at the value of per unit area yield of super rice higher than average national per unit area yield,the increase of super rice planting area will increase the rice yield more than 11 million tons by 2020.
Gap between the yield of super rice growers and the yield of 100 mu demonstration paddy fieldThere is still a big gap between the yield of super rice growers and the yield of 100 mu demonstration paddy field.The gap is about 25% -31%.
Gap between average national rice yield and the yield of 100 mu demonstration paddy fieldThere is a big gap between average national per unit area yield and the yield of 100 mu demonstration paddy field.The yield over the years indicated that the yield of 100 mu demonstration paddy field is one time higher than the current average national rice yield.By 2020,the average national rice yield will be 43% of the yield of 100 mu demonstration paddy field.When the average national rice yield reaches 60% of the yield of 100 mu demonstration paddy field,China’s total rice yield will exceed 230 million tons,to which expansion of super rice planting area and increase of per unit area yield contribute a lot.
Through comparison between current average national rice yield and actual super rice yield of rice growers,planting superrice forone more hectare can satisfy grain ration demand for 8.44 more people.However,if planting conventional rice in this one hectare land,the rice yield will reduce about grain ration of 3.52 people.In the situation of current rice yield of rice growers(2014),we made the comparison between super rice and conventional rice in the number of people they feed(shown in Table 6).
On the basis of per unit area yield of rice growers we surveyed,super rice can increase grain yield,save farmland,and feed more people for China.At different stages,the values are different,and predicted values are listed in Table 7.
In future 5-10 years,when the percentage of super rice area reaches 35%,45%,and 50% of total rice area,if the yield of other crops keeps unchanged,super rice can produce more grain about 4.958 million tons,13.723 million tons,and 18.506 5 million tons respectively,save farmland about 0.786 6 million hm2,2.078 7 million hm2,and 2.846 7 million hm2respectively,and separately feed people for 1.8 million,55 million,and 72.4 million more.For increase of 1% of percentage of super rice area to total rice area,it can at least produce one more million tons of rice,save farmland about 133 300 hm2,and feed 3.2 million to 3.5 million people more.
In sum,super rice is a powerful guarantee for stable growth of China’s grain yield,constantly increasing grain ration demand,and food security under the condition of constantly shrinking farmland.
Grain is always first priority of China’s social stability and people’s happiness.Government and state also always take solving grain issue as their political mission.Current situation of much population but little land makes it more urgent for China to produce more grain in limited farmland.For this,Chinese government launched research of super rice breeding 20 years ago and this research has made special contribution to increase of China’s grain yield and development of grain ration demand.With near 20 years of development,super rice has successively made record in researches and per unit area yield in small area,and constantly breaks the record of per unit area yield and this impetus is not abating.In current situation,super rice research develops rapidly,but government promotion and expansion of technical personnel develop slowly and need acceleration.How to realize the percentage of super rice area to 50% -60% in next 5 to 10 years?It is difficult to realize this goal merely relying on demonstration and extension of researchers in time,effort,and fund.More important,it is required to drive the two wheels,i.e.“government promotion” and “technical extension”,to realize uniform advance of three wheels (expert research,government promotion,and technical extension),so as to change the current situation of few administrative leaders talking about super rice and few farmers knowing the low proportion of super rice area.
In recent years,China’s per unit area yield of rice is increasing year by year,but due to shrinkage of rice planting area,total rice yield is dropping.Although super rice expert research and farmer’s production are advancing,the enthusiasm of experts is obviously higher than that of farmers.Reasons for this are as follows:comparative benefit of planting rice is slightly low;there is special program and levels of financial support for research of super rice,while in production and technical extension,there is still no special plan;except various agricultural subsidies,there is no special plan related to extension of super rice for counties(cities)and farmers of super rice production.In this situation,China should set up financial extension and subsidy plan for major super rice production provinces,counties,and rice growers,extension units,and relevant organizations,and encourage technicalextension personneland farmers to produce and plant super rice,to increase the percentage of super rice in rice production.Besides,it is recommended to increase amount of subsidies for super rice research,production,and technical extension.
In the past 20 years,both central government and provincial level government have provided sufficient research funds for researches of super high yield rice varieties.This makes China’s super rice research level rank first in the world and the achievement is outstanding.Currently,at the same time of strengthening super rice research,it is recommended to increase fund input in extension of super rice.Super rice extension expert organizations and all levels of agricultural extension departments should take this responsibility,change the mode of research experts making patrol demonstration and extension personally,and help them focus on super rice research with more time and efforts.Besides,extension should be implemented under the guidance of extension experts,to fully bring into play enthusiasm of all levels of agricultural extension departments and implement guidance of experts in suitable time.At present,there is no special fund input in super rice extension in some main grain production provinces,cities,and counties.The extension fund merely comes from rice demonstration and extension fund of agricultural department and research and demonstration fund of research institutions.Such fund is extremely insufficient for provinces with tens of millions of mu super rice production and fails to realize all-round extension and development of super rice.Therefore,competent authorities should implement the annual arrangement and input of super rice extension fund according to“one yuan for one mu”amount of financial budget.
Rice production isinseparable from essential conditions such as land,sunshine,and water.Apart from fine seed,high yield of super rice is also closely connected with high quality soil condition,excellent irrigation facilities,and favorable climate.Climate is changeable and is independent of man’s will,but soil conditions and irrigation facilities can be improved artificially.China has made huge amount of input in farmland water conservancy irrigation facilities for a long time and it contributes a lot to increase of China’s grain yield.Nevertheless,due to large area of farmland,China should continue to increase input in farmland water conservancy infrastructure,especially in main super rice production areas,increase fund input in water and soil improvement,land consolidation,irrigation and drainage projects,and field road and bridge construction projects,to ensure full play of potential of super rice.
At the same time of creating hardware conditions for super rice production,it is recommended to attach great importance to software service of superrice,namely,strengthening training and service of farmers in super rice planting.Super rice planting needs high skills and technologies.Super rice research of China has ranked first in the world,but the operation is still not reaching corresponding level.At present,there is still a big gap of existing rural labor quality with high requirement of super rice planting.It is difficult for farmers to grasp key technologies of super rice planting.For this,government functional departments should enhance training of farmers in super rice planting under the plan and policy of state “Sunshine Training”.Agricultural technological service personnel should closely communicate with rural areas and actively help farmers to grasp super rice planting technologies and services.
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Agricultural Science & Technology2015年11期