Technical efficiency of hybrid maize growers: A stochastic frontier model approach

This study investigated the effect of credit constraints and credit unconstraints on the technical efficiency of hybrid maize growers in the Khyber Pakhtunkhwa Province(KPK) of Pakistan. The primary data were collected by a direct elicitation method from 510 maize growers of KPK Province. Stochastic frontier model techniques were used for technical efficiency analyses. The results revealed that the mean technical efficiency difference between the two groups was 10.2%. The results of technical inefficiency effect modeling demonstrated that education of the household head, family size, number of married family members, off-farm income, farming experience, tractor drill, water irrigation through a lined course, certified seed, extension services, household saving variables, and a credit size variable had positive effects on technical efficiency for both credit constrained farmers(CCFs) and credit unconstrained farmers(UCCFs). In addition, age of household head and fragmented land values had negative effects on technical efficiency for both groups. However, the interest rate had positive and negative impacts on the technical efficiency of CCFs and UCCFs, respectively. Our results have significant implications for policies related to land use, interest rate, and banking sector expansion in the rural areas of Pakistan.

Effects of long-chain fatty acid supplementation on the growth performance of grower and finisher pigs: a meta-analysis

Background: Supplementation of feed with long-chain fatty acids(LCFAs) during the grower and finisher phases has long been discussed as a growth promotion strategy in pigs, but its effects are inconsistent. The purpose of our study was to comprehensively evaluate its effects on the growth performance based on the average daily gain(ADG), average daily feed intake(ADFI) and gain: feed(G:F) ratio and to unveil the roles of the basal diet, LCFA concentration and LCFA saturation.Results: We searched the Pub Med and Web of Science databases(articles published from Jan 1 st, 2000, to Sep 30 th,2018;restricted to English) and compared LCFA-supplemented diets with control diets. We retrieved 2346 studies, 18 of which(1314 pigs, 26 records) were eligible for our analysis. We used a random-effects model to calculate the weighted mean differences(WMDs) and 95% confidence intervals(CIs). LCFA supplementation in the grower-finisher phase improved the ADG(WMD = 41.74 g/d, 95% CI: 8.81 to 74.66, P = 0.013) and G:F ratio(WMD = 0.019, 95% CI: 0.006 to 0.032, P = 0.003). For supplementation solely in the finisher phase, we found a similar performance in the ADG(WMD = 39.93 g/d, 95% CI: 26.48 to 53.38, P < 0.001) and G:F ratio(WMD = 0.019, 95% CI: 0.006 to 0.032, P < 0.001) but a reduction in the ADFI(WMD =-83.863 g/d, 95% CI:-156.157 to-11.569, P = 0.023). Specifically, approximately 5%LCFA supplementation in the finisher phase had significant effects on the ADG(WMD = 51.385 g/d, 95% CI: 35.816 to66.954, P < 0.001), ADFI(WMD =-102.869 g/d, 95% CI:-189.236 to-16.502, P = 0.02) and G:F ratio(WMD = 0.028, 95%CI: 0.018 to 0.039, P < 0.001), whereas a concentration of approximately 1% exhibited no effects.Conclusions: Overall, regardless of the basal diet and saturation, LCFA supplementation greatly improves the growth performance of grower and finisher pigs, primarily by increasing the energy density.

Rice Growers' Behavior of Productive Capital Input and the Influencing Factors——A Case Study of the Jiamusi Area in Heilongjiang Province

This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 2009 in Huanan County and Huachuan County,Jiamusi City,Heilongjiang Province.I use Logit model to carry out econometric test of factors influencing the possibility of fixed productive investment.The test results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level,peasant households' expectation of the minimum purchase price of rice,have significant effect on whether to conduct fixed productive investment,whether there are disasters has no significant effect on the scale of peasant households' productive investment.Then I use Tobit model to carry out econometric test of factors influencing the scale of productive capital input.The results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level and family housing value,peasant households' expectation of the minimum purchase price of rice,whether there are disasters,have significant effect on the scale of peasant households' productive investment.On the basis of model test results,in order to promote the rice growers to increase fixed productive input and increase productive capital input,rational recommendations are put forward as follows:raising the minimum purchase price of rice,scaling up rice growing,making every effort to promote the educational level of rice growers,ensuring that the rice growers obtain productive capital input loans timely.

Dietary substitution of soybean oil with coconut oil in the absence of dietary antibiotics supports growth performance and immune function in nursery and grower pigs

Background:We hypothesized that supplementation of nursery and grower pig diets with coconut oil in the absence of antibiotics would yield maintenance of glucose homeostasis,growth performance,and immune function similar to what is achieved with nursery and grower pig diets containing antibiotics.Pigs received the same base treatment diets from d24(weaning)to d71 of age and had blood and fecal samples collected on d24,d31,d45 and d71 for measurement of whole blood glucose,serum insulin,cortisol and cytokines,and fecal microbiome.Pigs had weekly weights and daily feed consumption measured throughout the study.Animals were euthanized at d71 and subcutaneous fat and ileal contents were collected for assessment for fatty acids and microbiome,respectively.Diet treatments consisted of 2%soybean oil plus antibiotics(ABX;n=22),2%soybean oil without antibiotics(NABX;n=22),and 2%coconut oil without antibiotics(COC;n=22).Statistical analysis examined the effect of diet within each timepoint using a repeated measures ANOVA.Results:Pigs fed COC diet had decreased serum insulin levels,maintained feed intake,feed conversion and weight gain,and,based on serum cytokines and fecal microbiome,were immunologically similar to ABX-fed pigs.However,NABX-fed pigs performed similarly to the ABX-fed pigs in all parameters except for serum cytokines.Additionally,there was no difference in the incidence of diarrhea between any of the diet treatments.Conclusions:This study demonstrates that dietary antibiotics are not necessary to maintain growth performance in nursery and grower pigs.However,dietary antibiotics appear to modulate circulating cytokine levels.Dietary coconut oil is neither harmful nor helpful to growth performance or immune function in nursery and grower pigs but does modulate serum insulin levels.Therefore,while coconut oil fed at 2%by weight is a suitable substitute for dietary antibiotics,this study suggests that no substitute for dietary antibiotics is needed at all.

Fruit Growers' Opinions About Bird Conservation in North Part of Tarim Basin

A total of 216 survey interviews were completed in the orchards of the Aksu Region and the outskirts of Korla City, in October, 2009. The questionnaire was structured around fruit growers＇ opinions about insect pest management, bird conservation and included brief profiles of the growers＇ social background. The results showed that pest management was a great concern to all types of orchard growers and more than half of them would like to attract more birds to their orchards. The age, income level, education level and the orchard type of the fruit growers had significant effects on their opinions about bird protection.

Major Grain Growers in Jiaojiang District,Taizhou City

Based on the survey data of major grain growers in Jiaojiang District,we make a thorough inquiry into the current situation and various problems concerning major grain growers in this district,explore the factors that affect major grain growers' operation behavior,and set forth corresponding countermeasures for solving these problems and promoting further development.

Study on the Production Benefit of Large-scale Tobacco Growers

The tobacco growers with the growing area of greater than or equal to 100 mu,have become an important subject of tobacco production in Weng'an County of Guizhou Province. Regulating and developing the production and business activities of large-scale tobacco growers, plays an important role in stabilizing tobacco production,reducing costs and increasing efficiency in Weng'an County. Through the field survey of large-scale growers' production activities,this article analyzes the input and output levels,and explores the key factors influencing benefit, in order to provide a basis for further regulating the tobacco growing practices and improving the flue-cured tobacco production benefit.

数字能力如何促进农户农田碳汇技术采纳?——基于山东省粮食种植户的微观证据

数字化是驱动农业高质量发展的强劲动能,研究数字能力对农户农田碳汇技术采纳的影响,有助于为农业生产实现“双碳”目标提供新思路。本文基于山东省408个粮食种植户的微观调研数据,从数字接入、数字使用和数字转化3个维度构建数字能力指数,利用Oprobit模型实证分析了数字能力对农户农田碳汇技术采纳的影响。本研究发现:1)数字能力提升有助于农户农田碳汇技术采纳,且分维度来看,数字使用能力的影响效应高于数字接入能力和数字转化能力,是促进农户实施农田碳汇技术的关键因素。2)提高农户数字能力可以通过增加土地流转和提高机械化生产水平促进农田碳汇技术采纳。3)数字技术推广强化了数字能力对农户农田碳汇技术采纳的影响,且正规推广的效力高于非正规推广。为此,未来应加强农户数字能力培训,并重视不同维度数字能力的作用差异,增强其与数字技术推广的互动功能,为我国农业绿色低碳转型奠定良好基础。

蔬菜种植户安全用药行为及影响因素研究——以山东省为例

选择中国蔬菜种植大省山东省为主要调研对象,在分析山东省蔬菜种植户安全用药行为的基础上,探究蔬菜种植户安全用药行为及影响因素,以期为引导蔬菜种植户安全用药的相关政策制定提供科学依据,进而提高山东省的蔬菜质量安全。运用二元Logistic回归模型以及ISM模型进行实证分析,实证结果显示:蔬菜种植户年龄、受教育程度、是否参加农民合作社、是否参加过蔬菜种植技术培训以及对农药政策的了解情况的显著度分别为0.008、0.001、0.071、0.075和0.075,回归系数分别为-0.866、0.917、0.696、0.793和0.863。说明蔬菜种植户的年龄对其安全用药行为存在显著负向影响,蔬菜种植户受教育程度、是否参加农民合作社、是否参加过蔬菜种植技术培训和对农药政策了解情况对其安全用药行为存在显著正向影响,且蔬菜种植户是否参加过蔬菜种植技术培训和对农药政策了解情况作为表层因素处于阶梯结构的第一层,蔬菜种植户是否参加农民合作社作为中层因素处于阶梯结构的第二层,蔬菜种植户的年龄和受教育程度作为深层因素处于阶梯结构的第三层。针对实证分析结果提出以下对策建议:提供安全用药技术指导;加大安全用药培训力度;提升意识与科学用药并重;施行绿色农药补贴政策;推动以农民合作社为主的蔬菜生产模式;构建农药检测监督机制。

具有改进的Leslie-Grower式的Holling-Tanner模型的稳定性分析

研究一个具有改进的Leslie-Grower式的Holling-Tanner模型.分析了该系统的平衡点性态,利用Dulac函数证明了系统在正平衡点外围不存在极限环,从而证明了正平衡点在第一象限内是全局渐近稳定的.

人际信任对农户水稻绿色种植技术采纳行为的影响——基于政策激励的中介效应

基于江汉平原372份微观调研数据,运用有序Probit回归模型,探究了人际信任对农户水稻绿色种植技术采纳行为的影响及作用机制,并分析了政策激励在其中的传递机制。结果表明:①情感信任和认知信任均对农户水稻绿色种植技术采纳行为具有显著的积极影响,并且情感信任比认知信任更具促进作用;②情感信任和认知信任之间不会产生交互作用;③政策激励在情感信任和认知信任对农户水稻绿色种植技术采纳行为的影响中均具有部分中介效应。因此,要促进农户水稻绿色种植技术采纳行为,不仅要提高农户的人际信任水平,还要加强相关政策激励的实施力度。

Growth performance of nursery and grower-finisher pigs fed diets supplemented with benzoic acid

Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initial body weight as the blocking factor. There were 3 treatments corresponding to 3 dietary levels of benzoic acid: 0, 0.3%, and 0.5%. In experiment 1, a total of 144 PIC L1050 barrows(initial body weight 7.1 ± 0.6 kg) were used with each treatment replicated 8 times. In experiment 2, a total of 288 PIC L1050 barrows(initial body weight 36.1 ± 3.6 kg) were used with each treatment replicated 16 times.There were 6 barrows in each replicate pen for both experiments. Experiments 1 and 2 lasted 28 and 70 days, respectively. In experiment 1, average daily gain(ADG) of all growth phases increased linearly(P < 0.05) with increasing supplementation of benzoic acid, which led to a linear improvement in average body weight on d 28(P < 0.05). There was also an improvement in feed conversion ratio(FCR) of d 0 to 14(linear effect: P < 0.05) and in average daily feed intake(ADFI) of d 14 to 28 and d 0 to 28(linear effect:P < 0.01). In experiment 2, ADG during d 0 to 35 and d 35 to 70 and average body weight on d 35 improved linearly(P < 0.05) with increasing supplementation of benzoic acid. Average daily gain of d 0 to70 and average body weight on d 70 increased significantly in a both linear and quadratic manner. There was a linear improvement in FCR in all growth phases(P < 0.05). In conclusion, the dietary inclusion of benzoic acid at the supplementation levels of 0.3% and 0.5% significantly improved the growth performance of nursery and grower-finisher pigs in the current study; the nursery pigs responded to the dietary supplementation of benzoic acid up to 0.5% linearly while the grower-finisher pigs achieved the optimal ADG at the calculated supplementation level of 0.36%.

政府培训、价值认知与种粮大户绿色技术采纳行为——基于家庭生命周期理论

运用435份种粮大户数据,在建立粮农绿色技术采纳综合评价体系的基础上,采用有序Logit模型分析政府培训和价值认知对粮农绿色技术采纳行为的影响,并关注价值认知的中介作用以及在不同家庭生命周期阶段粮农采纳绿色技术行为的差异。结果表明:政府培训总体上对粮农绿色技术采纳有显著正向影响;价值认知在其中起到了中介作用;在家庭生命周期各阶段中,处于稳定期的粮农有望成为绿色技术采纳的主力军。

土地确权能够优化农户农地质量保护行为吗?--基于苹果户正向行为和逆向行为的再检验

基于黄土高原苹果产区苹果户的调查数据,探析农地确权对农户农地质量保护中正向行为和逆向行为的影响。研究表明:农地确权有效促进了苹果户的正向行为投入,该促进作用主要体现于投资回报期限较长的正向行为,且主要通过安全效应实现;但农地确权并未促使农户减少逆向行为投入,反而对逆向行为农药投入产生正向影响。PSM模型、工具变量法和替代变量法检验结果依然支持该结论。进一步讨论还发现,农户损失厌恶、风险规避、路径依赖心理和有效替代行为缺乏是造成农地确权未对农户逆向行为形成负向激励的主要原因。需通过促进替代行为对逆向行为的有效替代和完善农业要素市场,强化农地确权对农地质量保护行为的优化作用。

土地经营规模对农户化肥投入的影响

基于土地经营规模对农户化肥投入影响的机理进行分析,结合贵州省赫章县古基镇海子村玉米种植户的调研数据,采用OLS计量方法探究土地经营规模对农户化肥投入的影响机理。结果表明:整体而言,土地经营规模对农户化肥投入具有显著的负向影响。具体来看,土地经营规模与农户化肥投入存在“U”型关系,即农户化肥投入水平随着土地经营规模扩大呈现出“先减后增”的变化趋势。其中,当土地经营规模为0.76 hm^(2)时,农户化肥投入量达到最低水平。此外,提高农户受教育程度、加入合作社、接受施肥相关技术培训以及降低土地细碎化程度和提高土壤质量等影响因素均有助于农户化肥的减量投入。据此,当地政府应当鼓励和引导农户适当扩大土地经营规模;充分发挥合作社作用,加强施肥相关技术培训;加大土地保护性投入力度,改善土壤质量,从而达到化肥减量投入的效果。

提高种粮积极性:中国粮食生产支持政策的完善与转型

创新和完善粮食生产支持政策、保护和提高种粮积极性,是中国粮食安全之路行稳致远的重要保障。因粮食生产支持政策承载了“确保口粮绝对安全”重任和多元目标,以及部分政策的实施机制和环境发生重大变化,引发了粮食市场扭曲严重、经济社会代价高昂、实际种粮者受益减少、粮食产业链供应链受困、合规性挑战和贸易争端等问题。据此,要坚持目标导向和问题导向,将粮食生产支持政策体系重心转到支持粮食综合生产能力建设、种粮者利益保障、主产区粮食产业集群和粮食产业经济发展上去。同时,应积极探索“政策保本兜底稳预期、市场提质优价促增收、科技节本增效提效率”的种粮者利益保障机制,让政府和市场协同发力共保种粮者基本利益。这种政策的创新完善和转型升级,既能夯实粮食产能基础,也能让实际种粮者和主产区抓粮者受益,同时可提升中国粮食生产支持政策的系统性、精准性、合规性和实效性。

信息获取能力会影响果农的销售渠道选择吗?

进入数字经济时代后,信息逐步成为影响农户行为决策的关键因素。本研究基于行为转变理论和计划行为理论,利用来自中国黄土高原优势产区1074户微观数据,通过运用Ordered Probit模型,实证检验信息获取能力对果农销售渠道选择的影响,并进一步运用条件混合过程估计法(CMP方法)对模型进行了内生性检验。研究结果表明:(1)当前,传统销售渠道的中间商(果贩)仍然是果农销售农产品的主要方式;(2)信息获取能力对果农销售渠道的选择有显著正向影响,即信息工具使用水平对果农进入市场壁垒更高的销售渠道具有促进作用;(3)信息获取能力正向显著影响新、中生代苹果户群体对销售渠道的选择。因此,政府应在完善农村信息基础设施和信息服务体系的同时,优化升级农产品流通体系,重点对新生代农户开展信息技术培训,提升其信息获取能力。

农业社会化服务能否促进小麦种植户绿色生产转型?——基于河南、山东、山西的农户调查证据

农户绿色生产转型能在一定程度保障农产品质量安全、缓解农业环境压力,明确农业社会化服务对农户绿色生产转型影响程度有重要意义。该研究基于河南、山东、山西1018份农户调研数据,在运用有限混合模型测算农户绿色生产转型度的基础上,采用倾向得分匹配法(PSM模型)构建反事实假设,估计农业社会化服务对农户绿色生产转型度的平均处理效应及其异质性。研究结果表明:①小麦种植户生产方式可依据相关指标划分为传统生产方式与绿色生产方式两类,进行绿色生产的小麦种植户占比20.33%,其化肥减施量为363.35 kg/hm^(2),农药投入费用降低418.73元/hm^(2)。②施肥服务与植保服务对小麦种植户绿色生产转型具有显著促进作用,其平均处理效应分别为0.109和0.152。相较于施肥服务,植保服务对小麦种植户绿色生产转型促进作用更强,农户购买施肥、植保服务后,相应每公顷化学投入品成本分别降低204.06元和284.56元。③农业社会化服务对农户绿色生产转型的影响具有显著异质性,参加过农技培训的农户与兼业农户购买农业社会化服务的绿色生产转型效应更为显著。为此,应大力培育农业社会化服务市场、加强对不同环节农业社会化服务的扶持、引导不同禀赋的农户合理购买农业社会化服务,有针对性地促进农户绿色生产转型。

价值认知、制度环境对种粮大户质量安全控制行为的影响及其代际差异

基于粮食主产区湖南、山东两省436份种粮大户调查数据,运用二分类Logit模型实证分析价值认知、制度环境对种粮大户质量安全控制行为的影响及代际差异,并检验制度环境在价值认知影响种粮大户行为中的调节效应。结果表明:价值认知对种粮大户质量安全控制行为有正向作用,其中社会价值认知对中生代种粮大户的影响更为显著,生态价值认知对新生代种粮大户的影响更为显著;引导制度、激励制度对种粮大户质量安全控制行为具有正向作用,其中引导制度对新生代和中生代种粮大户的影响更为显著,而约束制度对老一代种粮大户质量安全控制行为有显著的抑制作用;制度环境是种粮大户价值认知与质量安全控制行为之间的重要调节变量,约束制度和激励制度在价值认知对老一代种粮大户质量安全控制行为的影响中有负向调节效应。