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1.
The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop season, we performed a probit model(plot-level analysis) to determine the probability of adopting new improved rice varieties(NIRVs) by smallholder farmers particularly from two main agro-ecological regions(hills and tropical plain terai regions) of Central Nepal. The results revealed that education, extension services and seed access play significant roles in adoption decisions.Additionally, farm and field characteristic variables such as farm size, endowment of favorable land type(e.g. lowlands), and animal power(e.g. oxen) are the key factors influencing the probability of adopting NIRVs. The results showed that technology specific variables(e.g. yield potential and acceptability) are significant for explaining adoption behavior, implying that it is important to take farmers' preferences to varietal characteristics into consideration in the design of a research and development program. Given the significant role played by extension and access related variables, increased emphasis on information dissemination, field demonstration, and farmers' participatory research and training programs to popularize new rice varieties and enhance their adoption rate are required. This also suggests that policy intervention should be made on improving the educational status of farming households, and developing programs on varietal package of rice seed which offer farmers a variety of choices among the appropriate pools of germplasm. Such programs ultimately help farmers develop more profit-oriented behavior which are necessary to enhance adoption rate, production and food security in the long run.  相似文献   

2.
水稻低碳生产研究进展   总被引:11,自引:0,他引:11  
 稻田是甲烷(methane,CH4)和氧化亚氮(nitrous oxide,N2O)的重要发生源。稻田中CH4和N2O的产生、消耗以及传输过程受稻田土壤类型、水分条件、肥料种类、施肥量及方法、耕作模式和制度、水稻品种等多种因素影响。CH4和N2O具有不同的排放特性,很多研究结果表明,水稻生长期间的中期排水烤田、后期干湿交替能显著降低CH4排放量,但同时也可能促进N2O的排放,因此,如何同时减少CH4和N2O的排放量是实现稻田低碳生产的关键要素;另一方面,稻田土壤的碳固定也是使稻田系统从源转变成汇的关键技术。从水稻生产过程中CH4排放、N2O排放、稻田土壤有机碳动态、减排措施四个方面综述了近年来水稻低碳生产相关研究状况,重点总结了国内外有关影响稻田CH4和N2O排放的关键影响因素、增加稻田土壤有机质含量的主要措施以及各种减排措施的全球增温潜势评价研究,并对水稻低碳生产研究作了展望。  相似文献   

3.
Factors affecting the adoption of double cropping were explored in rice farms of Fouman County of Guilan Province in northern Iran using artificial neural networks (ANNs), linear discriminant analysis (LDA), and logistic regression (LGR). Eleven factors (age, education, occupation, family size, type of farm ownership, distance to the agricultural service center, attending agricultural extension courses, use of financial resources and bank loans, number of domestic animals, area under cultivation, and social participation) were examined. An additional objective was to compare the ability of the three models in predicting the adoption of double cropping. ANNs showed an overall predictive power of 89.8%. LDA showed an overall predictive power of 83.2%, with seven of the eleven independent variables being effective on the adoption of double cropping. LGR indicated an overall predictive power of 87.6%, with eight of the eleven independent variables being effective on the adoption of double-rice cropping. ANNs showed higher power than LGR and LDA in predicting the adoption of double cropping. Based on all three methods used for analysis, the most important independent variables were social participation and area under cultivation (positive factors) as well as distance to the agricultural service center and family members (negative factors). Establishment of cooperatives or other kinds of farmers’ associations to foster social participation could motivate adoption of double cropping, particularly among small-scale farmers. To increase agricultural services, more local centers should be created in rural areas. The government should promote double cropping through effective incentives and technology transfer to small-scale farmers.  相似文献   

4.
5.
Unbalanced and excessive use of N-fertilizers causes environmental pollution, lodging of plants and increased pest pressure, in addition to increased cost to farmers from excessively applied fertilizers and pesticides. N application at the right time and in right amount is critical for healthy plant and environment. Rice leaf color intensity is directly related to leaf chlorophyll content and leaf nitrogen status. The concept for the use of leaf color as an indicator to apply N in rice was crystallized during 1990s. The International Rice Research Institute and the Philippine Rice Research Institute developed a leaf color chart (LCC) that helps guide farmers for real-time nitrogen management in rice farming. The technology is inexpensive, and easily affordable by most resource poor rice farmers. In 2003 we initiated a farmer-participatory research to validate real-time N management in rice by the use of LCC in West Bengal state of India. After 3 years of validation research, a survey was conducted to assess the adoption and impact of LCC. The survey was conducted in both intervention and adjacent control villages and data were collected from 20% farm households selected randomly. In this paper, we report findings of the study on the determinants of adoption of LCC, and its effect on fertilizer and pesticides use.  相似文献   

6.
Controversy surrounds the promotion of conservation agriculture (CA) in smallholder farming systems in sub-Saharan Africa. The introduction of CA is a profound change in farm management. Benefits in reduced erosion and stabilized crop production may be obtained, but technical performance at field level is but one of the determinants of adoption. For various reasons, all of the CA principles are not always fully implemented by farmers and results not as favourable as expected. As with other approaches to increasing agricultural productivity, the production constraints, farmers’ objectives, and the expected benefits and costs of implementing CA are important aspects that influence adoption. At farm and village levels, trade-offs in the allocation of resources become important in determining how CA may fit into a given farming system. At a regional level, factors such as the market conditions, interactions among stakeholders and other institutional and political dimensions become important. At each level, opportunities or difficulties emerge that enhance or impede development, adaptation and adoption of CA. The ex-ante identification of situations for where CA (and which form of CA) is appropriate demands research from a multi-stakeholder, multi-level, and interdisciplinary perspective. Recommendations are made where research is required to address key knowledge gaps.  相似文献   

7.
ABSTRACT

Information on comprehensive evaluation of agricultural innovations is often limited. This study provides an overview of multidisciplinary evaluation of a lowland rice variety, WITA 9 (released in Côte d’Ivoire in 1998), with respect to its agronomic performance, grain quality, resistance to diseases, adoption by farmers, impact on productivity and farmers’ income, and marketability. WITA 9 had the highest paddy yield among the tested varieties including an international check (IR 64) and recently developed varieties adapted to this country. WITA 9 had a higher amylose content (26–28%) than others tested. This study confirmed its resistance to bacterial leaf blight, Rice yellow mottle virus (RYMV), and rice blast. A household survey showed that the adoption rate was 24%, its paddy yield advantage was 0.7 t ha–1, and its adoption increased farmer’s income by US$ 91 ha–1 per season. A market study showed that consumers’ willingness to pay was higher for WITA 9 than any other locally produced rice variety and comparable to imported rice in one of two markets. We conclude that WITA 9 is an ideal innovation for enhancing productivity and rice import substitution in Côte d’Ivoire. An effective seed delivery system and enhancing farmers’ and consumers’ awareness of this variety are vital for accelerating impact.  相似文献   

8.
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17.  相似文献   

9.
While research on biological control of crop pests is quite popular, it seldom targets motivations of farmers for adopting this practice. A survey of 283 rice farmers was conducted in Mazandaran province of northern Iran to study farmers' motivations for biological control adoption as an alternative control method of Asiatic rice borer [Chilo suppressalis (Walker)] and explain potential differences in motivations among different groups of farmers. Face to face interviews were used to address farmers' motivations based on a list of motivation statements found in previous studies and modified by extension officers and farmers who had adopted biological control in the study area. Factor analysis of a motivation list with 15 items revealed four main groups of factors explaining the adoption of biological control by rice farmers; these were ‘health maintenance’, ‘economic benefit’, ‘social acceptance’, and ‘environmental protection’. Men gave high scores to motivations related to ‘economic benefit’ and ‘social acceptance’, whereas women preferred mostly motivations related to ‘health maintenance’. Well-educated farmers (e.g., some college education) preferred motivations for ‘health maintenance’ more than farmers with lower education or no education at all. Participation in extension programs was associated with preference of non-economic motivations of biological control adoption, while membership in local associations (such as rural cooperatives or producers' groups) encouraged motivations related to ‘social acceptance’. Farmers who used family labor force in their fields or farmers who perceived pesticides as harmful substances showed strong motivations primarily for ‘health maintenance’ along with ‘environmental protection’. Small area of land under cultivation and low annual farm income were strongly linked with motivations for ‘economic benefit’. Besides economic motivations, policies for the promotion of biological control adoption should embrace a wide set of farmers' motivations when developing new and properly tailored extension programs.  相似文献   

10.
Yield decline is a major constraint in the adoption of monocropping of aerobic rice. The causes of the yield decline in the continuous aerobic rice system are still unknown. The objective of this study was to determine if nutrient application can mitigate the yield decline caused by continuous cropping of aerobic rice. Micro-plot experiment was conducted in 2005 dry season (DS) in a field where aerobic rice has been grown continuously for eight seasons from 2001 DS at the International Rice Research Institute (IRRI) farm. Pot experiments were done with the soil from the same field where the micro-plot experiment was conducted and aerobic rice has been grown continuously for 10 seasons. Apo, an upland rice variety, was grown under aerobic conditions with different nutrient inputs in field and pot experiments. The field micro-plot experiment showed that micronutrients had insignificant effect on plant growth under continuous aerobic rice cultivation but the combination of N, P, and K mitigated the yield decline of continuous aerobic rice. A series of pot experiments studying the individual effects of nutrients indicated that N application improved plant growth under continuous aerobic rice cropping, while P, K, and micronutrients had no effect. Increasing the rate of N application from 0.23 to 0.90 g per pot in the continuous aerobic rice soil increased the vegetative growth parameters, chlorophyll meter readings, and aboveground N uptake consistently. Our results suggested that N deficiency due to poor soil N availability or reduced plant N uptake might cause the yield decline of continuous cropping of aerobic rice.  相似文献   

11.
We evaluated the factors influencing the adoption of rice-fish farming in the Tavalesh region near the Caspian Sea in northern Iran.We conducted a survey with open-ended questions.Data were collected from 184 respondents(61 adopters and 123 non-adopters) randomly sampled from selected villages and analyzed using logistic regression and multi-response analysis.Family size,number of contacts with an extension agent,participation in extension-education activities,membership in social institutions and the presence of farm workers were the most important socio-economic factors for the adoption of rice-fish farming system.In addition,economic problems were the most common issue reported by adopters.Other issues such as lack of access to appropriate fish food,losses of fish,lack of access to high quality fish fingerlings and dehydration and poor water quality were also important to a number of farmers.  相似文献   

12.
崔福海 《北方水稻》2004,(Z1):85-86
分析了农场水稻生产经营的现状,指出了农场发展水稻产业化的资源、管理、政策优势,根据实际情况,具体实施科技种田,引进优良品种,改善生态环境,扩大名牌效应等环节,实现监狱农场水稻的产业化经营。  相似文献   

13.
Laser land leveling has been increasingly adopted in the irrigated rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system in the state of Haryana (India), located in the north-western Indo-Gangetic Plains. Still, many farmers have applied it to only a fraction of their land. In this study, we used data collected from 621 farm households in Haryana and applied a double-hurdle model for assessing the factors that determine the adoption and intensity of laser-leveling technology. The results show that large land holders are more likely to laser level their farm land; however, we found a negative association between land holdings and the proportion of laser-leveled land. Information about technology through farmer-to-farmer communication and through private traders, participation in agricultural training and membership in local agricultural institutions increased both the likelihood and the intensity of adoption. Our findings call for a closer collaboration among the various stakeholders, specifically to promote farmer-to-farmer communication through increased participation in local institutions and increase the rate of adoption of laser leveling technology.  相似文献   

14.
赵黎明 《北方水稻》2009,39(6):63-69
随着我国科技力量的飞速发展,科学家们在激素受体基因分离鉴定、激素控制株型以及激素间的相互作用等方面取得了突破性进展,其中生长素(IAA)在协调体内外调节机制中起着不可或缺的作用;细胞分裂素(CTK)可以通过对细胞分裂与分化的调节而参与对水稻生长发育的调控;赤霉素作为植物生长的必需激素之一,调控植物生长发育的各个方面,如:种子萌发,下胚轴的伸长,叶片的生长和水稻开花时间等;脱落酸(ABA)同样也是一种重要的植物激素,受到生物胁迫和非生物胁迫的调控,在水稻对胁迫耐受性和抗性中发挥着重要作用;乙烯(ETH)则是一种多功能的植物激素,它在水稻生长发育和应对生物及非生物胁迫过程中起着重要作用。本文着重阐述了近几年植物激素在生理学研究方面的研究进展,提出了我国在植物激素研究领域的未来发展方向与趋势,同时也展望了植物激素研究对水稻重要农业性状改良的意义。  相似文献   

15.
Eight-element contents of 653 unpolished rice samples harvested from Xingping experiment farm, Yunnan Province under thc same ecological conditions were analyzed by ICP-AES method. The mineral elements content were closely related to low diversity, high-yielding, and multi-resistance breeding; The K, Mg, Ca and Mn content in high-yielding and resistant varieties were high, and other nutrients such as P, Fe, Zn and Cu were low, which was connected with the heredity and physiological mechanism of mineral nutrients. There is zonal distribution of mineral elements content from Yunnan rice, especially for P, Fe, Zn and Cu co-related with the diversity center, paddy versus upland, glutinous and non-glutinous, glumc-hair versus nuda, rice color, rice flavor, soft rice versus non-soft rice, but it did not find any association with indica-japonica types. The results supported the ecological variety group view of 5-grade taxonomic system “species-subspecies-ccological groups-ecological variety groups - varietal types“ .  相似文献   

16.
In recent years, the Israeli wheat industry has suffered from quality problems that can endanger the possibility of using the wheat to produce bread. The aim of this study is to understand how climatic and management factors, such as N fertilization, emergence date and wheat cultivar, affect the Gluten Index (GI) - a main wheat quality parameter in the Israeli commercial market. The study was undertaken at individual producer fields across southern Israel on three different scales: regional, farm, and the field. Overall, 1800 samples of 15 genotypes were collected, over three consecutive seasons, 2006-2008, from commercial fields throughout the area, from experiments conducted in the fields of the Gilat Research Center, and in the fields of Kibbutz Sa’ad. Climatic variables were mapped exclusively and on the basis of maximum temperature and rainfall data, and were collected in the course of the entire season and during certain periods. Relationships between climatic variables and GI were determined by multivariate regression analyses. On regional scale, the ability of explaining the differences was low, while on the farm and field scale, variation explanation was generally higher. The factors that were found to be most influential on wheat quality in southern Israel are: (1) type of variety; (2) negative influence of cumulative temperature stress; (3) negative influence of excess water; and (4) negative influence of excess nitrogen fertilization. It was found that the genotype is the most important factor influencing GI, but environmental and crop management factors also have a strong effect on the frequency and severity of GI depreciation. The probability of GI reduction increases in “too good” (excess fertilization, redundant irrigation) and in “too bad” conditions (water and temperature stress). Hence, when farmers make decisions regarding sowing, applying nitrogen and/or supplemental irrigation, they must also consider quality parameters, such as GI and not only yield quantity.  相似文献   

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18.
本文从影响蕉农技术采用行为因素分析入手,通过对广东香蕉主产区164户种植业农户的实地调查,运用Logistic模型探讨农户对新品种技术、灌溉技术、施肥技术、花果管理技术、病虫害防治技术和果园农机技术需求意愿及其影响因素。结果表明,不同家庭特征和技术诱导情况的蕉农表现出不同的需求行为,各解释变量对农户整体技术需求有影响,但对农户采用不同属性技术的影响各不相同。  相似文献   

19.
云南稻核心种质矿质元素含量及其变种类型   总被引:29,自引:2,他引:29  
用等离子体原子发射光谱法测定了在云南省新平县同时繁殖的653份云南稻种核心种质糙米中的P、K、Ca、Mg、Fe、Zn、Cu和Mn共8种矿质元素的含量,比较了云南稻种核心种质8种矿质元素含量与变种分类性状间的差异。结果表明高产多抗育种、多样性降低与矿质元素含量的变化密切相关;高产和多抗水稻品种的K、Ca、Mg、Mn含量明显增加,P、Fe、Zn、Cu含量则明显降低,这与水稻矿质营养的遗传和生理机制密切相关。云南稻种核心矿质元素含量存在地带性分布, P、Fe、Zn、Cu含量高低可能与多样性中心有一定联系。核心种质矿质元素高低及其多样性与籼粳关系不大,但在水陆、粘糯、光壳与否、米色、米味、软米与否之间差异明显。这些结果间接支持了“亚洲栽培稻种—籼粳亚种—生态群—生态变种群—品种类型”五级分类系统的生态变种群。  相似文献   

20.
Increasing water productivity for paddy irrigation in China   总被引:4,自引:0,他引:4  
This paper introduces the research on practices to increase water productivity for paddy irrigation in China and summarizes the experience on implementation of the alternate wetting and drying (AWD) irrigation technique. The widespread adoption of the AWD practice on 40% of the rice growing area provides an opportunity for China to produce more food in the water-surplus south where it is wet and the traditional based paddy field agriculture is dominant. Physical and institutional measures leading to increasing water and land productivity in rice-based systems are discussed. Research studies show that AWD practice does not reduce rice yield, but does increase the productivity of water. Water use and thus water charges can be reduced. However, experience shows that demonstrations and training are needed to encourage farmer adoption. Furthermore, there are a range of complementary policies and practices, such as volumetric pricing or farm pond development, which provide incentives for adoption of AWD. Finally, there remain many scientific issues to be addressed. Application of the AWD technique in some regions is still very difficult because of both bio-physical and socio-economic problems. In conclusion, the widespread adoption of AWD is only a first step in the continuing effort to find practices that will increase water productivity for paddy irrigation in China.Dr. Yuanhua Li was a Professor and Dean in Wuhan University of Hydraulic and Electric Engineering from 1996 to 2000. After that, he has been a Professor and Deputy Director General of the National Centre for Irrigation and Drainage Development, Ministry of Water Resources, China. He has been doing research on irrigation principally for paddy since 1982.Dr. Randolph Barker is an agricultural economist and Professor Emeritus Cornell University. From 1966 to 1978 he served as head of the Economics Department, International Rice Research Institute, Los Banos, Philippines and from 1995 to 2004 was principal researcher, International Water Management Institute, Colombo, Sri Lanka.  相似文献   

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