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Perceptions of Rice Farmers towards Production Constraints: Case Study of Niger State of Nigeria and Hainan of China 被引量:1
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作者 Ahmed Abdul-Gafar Shiwei Xu Wen Yu 《Journal of Agricultural Chemistry and Environment》 2016年第1期20-30,共11页
Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges... Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges and at what magnitude and more importantly, what can be learn to improve the rice yield in Nigeria. Based on 2013/2014 survey, a total sample of 400 famers were randomly interviewed;164 from Niger State of Nigeria and 236 from Hainan province of China. The study collate the perception of farmers to rice production constraints categorized into biotic, abiotic and socioeconomics. Biplot analysis was employed to examine multivariate pattern of their perceptions towards production constraints. The multivariate technique simultaneously displaying different yield levels and factor constraints in data matrix providing the inter-unit distances, variance and correlations of variables. According to the study, Niger state farmers identified socioeconomic constraint as the major factors to production and attributed it to lack of or insufficient investment while the Hainan farmers majorly identified abiotic constraints. The study also indicated that great potential remain to further improve rice yield in both regions especially in Nigeria given the appropriate investment on essential inputs. This study is of great use to extension officers more so, given the investment in Africa, policy makers take advantage of the bilateral and multilateral relationship to invest ease transfer of agricultural information and technologies between or among partners. 展开更多
关键词 Rice Farmers Production constraints Biplot Analysis Niger State Hainan Province
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Prevalence of Rice Diseases in Ogor and Orum Sub-counties, Otuke District
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作者 Bosco Bua Thomas Awio 《Journal of Agricultural Science and Technology(A)》 2012年第6期840-844,共5页
Rice (Oryza sativa L.) is an important food staple in most of the tropical and sub tropical countries of the world. In Uganda, rice has grown to become an important food security crop and source of cash income for t... Rice (Oryza sativa L.) is an important food staple in most of the tropical and sub tropical countries of the world. In Uganda, rice has grown to become an important food security crop and source of cash income for the majority of the rural farming communities across the country. Despite its importance, rice production has consistently remained low averaging 1.5 t/ha under farm conditions. The low production of rice is attributed to a number of production constraints. Therefore the objective of the survey was to ascertain the major production constraints in rice growing in the two sub-counties of Orum and Ogor, Otuke district. A diagnostic survey using semi- structured questionnaires was conducted in the two sub counties between July and August 2010 to gather information on the major production constraints from key informants, opinion leaders, farmers, technical and political leaderships. The findings showed that diseases were the major constraints in rice production accounting to 27% compared to other constraints. The other constraints included insect pests (23%), weeds (21%), drought (20%) and low prices (9%). The major diseases encountered were rice blast (30%), brown spot (23%), rice yellow mottle virus (19%), sheath rot (15%) and grain rot (13%). Overall, diseases accounted for 79% of the yield reduction in rice. The implication of these findings therefore is that diseases and other constraints in rice production must be adequately identified for easy management to ensure sustainable rice production. More importantly, farmers should be sensitised on disease recognition, means of spread and control. 展开更多
关键词 DISEASES rice production constraints
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THE EQUATION OF MOTION FOR THE SYSTEM OF THE VARIABLE MASS IN THE NON-LINEAR NON-HOLONOMIC SPACE
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作者 邱荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第4期379-386,共8页
The dot product of bases vectors on the super-surface of constraints of the nonlinear non-holonomic space and Mesherskii equations may act as the equations of fundamental dynamics of mechanical system for the variable... The dot product of bases vectors on the super-surface of constraints of the nonlinear non-holonomic space and Mesherskii equations may act as the equations of fundamental dynamics of mechanical system for the variable mass.These are very simple and convenient for computation.From these known equations,the equations of Chaplygin,Nielson,Appell,Mac-Millan et al.are deriv d;it is unnecessary to introduce the definition if Appell-Chetaev or Niu Qinping for the virtual displacement.These are compatible with the D'Alembert-Lagrange's principle. 展开更多
关键词 the non-linear non-holonomic constraints the system of the variable mass dot product.bases vectors on supersurface of constraints Misherskii equation
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