Impacts of transgenic Bt cotton and integrated pest management education on smallholder cotton farmers

Abstract

Comparative field research on transgenic Bt cotton and conventional cotton under different conditions (fields without pesticide inputs, fields managed by farmers with IPM education, fields managed by farmers lacking IPM education) were carried out in Hubei province of China in 2002. The amount of pesticide used on Bt cotton by non-IPM farmers was found to be around three times that used by IPM farmers. IPM farmers made significantly higher net profits from cultivating transgenic Bt cotton in comparison with non-IPM farmers. Other pest management practices had more significant influences on the population dynamics of predatory natural enemies and major insect pests than did the adoption of transgenic Bt cotton in the cotton ecosystem. Our study showed that IPM education, by increasing farmer capacity to critically evaluate inputs and their effects, monitor their fields and make informed decisions on pest management, enabled farmers to reduce pesticide use significantly, so resulting in improved production and profit margin. IPM farmer education thus, contributed to maximising the value of planting transgenic Bt cotton.     

环境规制约束下新疆棉农生产环境保护意愿与行为的影响因素研究

在农业面源污染较为突出的背景下,环境规制是否对新疆棉农的生产环境保护行为起到了规范作用?环境规制在治理农业面源污染中效果是否显著?这些问题成为全社会关注的问题.在对新疆重点植棉县的棉花种植户问卷调查的基础上,通过将环境规制分析归类为命令控制型、宣传教育型、经济激励型三种类型,运用SPSS17.0软件进行Probit双变...     

Smallholder cotton production in sub-Saharan Africa: An assessment of the way forward

Abstract

The benefits of growing organic cotton were advocated in a recent contribution to this Forum. While welcoming a debate on this subject, we advocate a closer look at the history of cotton in Africa, whereby for decades farmers did grow cotton without insecticides. We believe that while there may be a market for ‘organic’ cotton production, it would be a retrograde step to ignore the technological advances that enable much higher yields to be obtained economically. What is needed is improved training and extension services backed up by an on-going research programme for IPM/ICM utilising the most appropriate technologies. Continuing research is needed to integrate new technology of benefit to the small-scale farmer, whether aiming at organic production or higher yields by integrating rational use of biotechnology and pesticides.     

Farmer perceptions and pesticide use practices in vegetable production in Ghana

As an initial part of a programme aimed at promoting safe and sound agricultural practices in Ghana, a study was made of farmers' perceptions of pesticides for use and application in vegetable production, using a small survey of 137 farmers who applied pesticides. Field surveys, interviews, questionnaires and analytical games were used to obtain information on the type, scope and extent of use of pesticides, farmers' knowledge of pesticides, and their perceptions about the chemicals' potential for harm. Data from this sample of farmers were used to describe the status of use of pesticides in vegetable cultivation in Ghana. Using chi2 tests, associations between farmers' age and possible pesticide poisoning symptoms, their farm size and method of spraying pesticides, and their perception of pesticide hazard and its perceived effectiveness against pests were also examined. The survey showed that knapsack sprayers were the most widely used type of equipment for spraying pesticides. However, on large-scale vegetable farms of 6-10 acres, motorised sprayers were also used. Various inappropriate practices in the handling and use of pesticides caused possible poisoning symptoms among those farmers who generally did not wear protective clothing. Younger farmers (<45 years of age) were the most vulnerable group, probably because they did more spraying than older farmers (>45 years of age). Farmers did not necessarily associate hazardous pesticides with better pest control. The introduction of well-targeted training programmes for farmers on the need for and safe use of pesticides is advocated.     

粮食主产区农户耕地保护现状及认知水平分析——基于全国10个粮食主产区1198户农户的问卷调查

农户是耕地的直接使用者,农户的耕地利用行为在耕地保护中尤其耕地质量保护中扮演着重要的角色。鉴于当前针对农户耕地利用行为及耕地保护认知水平的研究尺度范围较小、难以代表全国大部分地区农户耕地保护的现状,文中基于全国10个粮食主产区1198份农户问卷调查,从大区域尺度上针对农户的耕地利用行为、利用效益及保护认知水平进行了调研分析。研究结果表明:1)研究区农户耕地利用现状不佳,耕地利用以短期效益为主,影响耕地质量的保护,农户的耕地保护认知水平总体较低;2)税费支农政策对大部分传统种植业农户家庭收入所起作用不明显,主要原因在于农业生产要素价格涨幅较大、农田基础设施不健全及户均耕地规模较小。最后针对上述问题,从加强农户耕地保护意识、改革农产品价格体系、建立农村社会保障体系、推进基本农田整治等方面提出相应的政策建议。     

如何辅导农民做农业科学试验研究

在解决棉花害虫防治的问题中,以山东棉区棉花去早蕾研究为例,阐述了农民田间学校的辅导员辅导农民做农业科学试验研究的方法和步骤,探讨了农技推广人员如何转变观念、简化方法,与农民一起学、做科学试验研究,这对我国农业技术推广方法的创新具有重要意义.     

Mapping potential exposure to drift of plant protection products*

A proposal for a practical, site‐specific approach for farmers has been developed to fulfil the drift restrictions and directions imposed on a registered plant protection product. The approach is based on exposure potential maps, primarily taking account of regional and local application conditions that reduce non‐target exposure. Firstly, the maps are focused on the spray drift exposure pathway. Using geographically referenced data, we have developed four exposure indicators that allow classification of potential non‐target exposure on the basis of local application conditions. This enables us to manage product application restrictions on a field‐to‐field basis by means of the exposure class to which each field is assigned. This easy‐to‐understand information can be distributed as paper maps or as digital maps to the farmer. The farmer himself no longer needs to assess whether local conditions reduce non‐target exposure. All calculations are carried out using very detailed topographic data which suit scales from 1:10 000 to 1:25 000. Processing and analysis of the GeoData is realized through GIS technology.     

Farmers’ attitudes towards pesticide labels: implications for personal and environmental safety

The label of pesticide containers is a major source of information for the use of pesticides, but research on whether farmers use this information is scarce. A survey of small-scale cotton farmers was conducted in the area of Punjab, Pakistan, to study attitudes related with the use of pesticide labels. The majority of the farmers (97%) stated that they were using pesticide products purchased in their original containers and accompanied by written information for use. However, 73% of the farmers reported that they usually do not read this information. Elderly, less educated, and experienced farmers in chemical pest control, but without previous training, were found to be less likely to read the labels. A large part of the farmers (34%) stated that they primarily rely on information of pesticide retailers for pesticide use, while nearly four out of ten said they usually rely on other sources of information or their own experience with pesticides. A sizeable proportion of the farmers (9%) mentioned that there is no need to receive information on such issues. Effective pesticide risk communication conveyed through label information is important so that potential risks from pesticide handling may be mitigated at the point of use.     

Insects and Mites

Abstract

Insecticide spraying trials conducted over a period of four years, 1970 to 1974, have shown that u.l.v. spraying using various formulations is as effective as conventional low volume sprays in increasing the yield of cowpea. More than ten-fold increase in yield may be obtained from a crop protected from insect damage by insecticide applications. In northern Nigeria where water is not often readily available the choice open to the farmer is to use u.l.v. spraying or not to spray at all.     

The influence of climatic factors on metoxuron activity on Bromus sterilis L.

Metoxuron was more active when Bromus sterilis L. (sterile brome) plants were kept under cool (10/6°C day/night) compared with warm (26/16°C) temperatures after spraying. The effect of warmer temperatures required exposure for more than 3 days. Metoxuron activity was unaflected by a cold exposure (0/-2°C or 4/2°C) for a 24-h period shortly before or after spraying. Greater damage occurred when plants were kept in high relative humidity (r.h.) (95/98% r.h. day/nighl) after spraying than at 75/86% r.h. or at 50/75% r.h. Increasing soil moisture from 11.5 to 21.5 g water 100 g^?1 dry soil also resulted in increased metoxuron activity. Metoxuron was less active under severe shading. There was little evidence in these studies that metoxuron activity resulted from foliar uptake. Results are discussed with reference to field reports of metloxuron use against B. sterilis. L.     

防治棉铃虫的药剂田间筛选试验研究初报

１９９１年通过对１５种农药、４３个处理防治棉铃虫第二代自然发生群体的田间药效试验表明：在当代始落卵孵化初期１次施药，效果较好的有爱力螨克和抑太保；卡死克和硫丹用较大剂量也有较好的效果；而Ｂｔ可湿性粉剂单独使用效果较差；在低龄幼虫期施药，以拉维因和多虫清的效果最好，其次为万灵，均能达到减虫、保蕾目的；马氰菊酯较低稀倍数下防治效果亦较明显；而好年冬和多来宝减虫效果较低，蕾铃受害较重；氰戊菊酯或敌杀死与     

转耐盐碱基因棉花生长发育及其对生物多样性的影响

为明确新型转基因棉花的生长发育、产量性状、生理生化指标及其对棉田生物多样性的影响,于2014—2015年对新型转耐盐碱基因棉花(13018)在施药和不施药条件下与其亲本对照中9807的生长发育及棉田生物多样性进行了系统调查和分析。结果表明,在棉花生长的关键时期苗期、蕾期和花铃期,无论施药与否,转耐盐碱基因棉花与亲本对照棉花间的单株叶面积、叶片干重、株高、主茎叶片数、主要生理生化物质含量均无显著差异,2种棉田中节肢动物个体总数、群落多样性指数、均匀性指数、优势集中性也均无显著差异。与亲本对照相比,在施药和不施药条件下,转耐盐碱基因棉花的单株大铃数在2014年分别增加了4.47%和12.65%,在2015年分别显著增加了59.51%和81.94%,表明转耐盐碱基因棉花较非转基因亲本棉花有较高的产量潜力。由此可见,新型转耐盐碱基因棉花在生长发育方面没有竞争优势,对棉田生物多样性无明显影响,产量构成性状在部分时期增强,具有较好的发展潜力。     

南疆棉花施氮量及氮素平衡分析

2002~2003年对塔里木盆地南缘的策勒县和北缘的尉犁县农户的棉田施氮现状进行了实地调查。结果表明:区内农户间施氮量差异较大,平均施氮总量达426~430 kg/hm2,过量施氮很普遍,分别有39.5%(策勒)和72.8%(尉犁)的农户过量施氮,施氮量与产量已经不相关,增加施氮已经不能增产,生产中应该遏止施氮量增加趋势,适当减少高施氮量。另外,还有6.2%~7.9%的棉田施氮量不足,这部分农户应该提高施氮量;策勒县偏重追施氮肥,单次追肥施氮量偏大,基追比为1∶5.12。尉犁县偏重基施氮肥,平均化肥基施量达171~273 kg/hm2,基追比为1∶0.48~1∶0.78,应通过减少基肥施氮量和单次追氮量,实现少量多次的氮肥施用策略,提高氮的利用效率;养分平衡计算结果表明,氮素盈余量达到87~248 kg/hm2;策勒和尉犁两个县总体上0~90 cm土壤N残留不高,只有10%~32%的棉田超过100 kg/hm2。     

Weed infestation is affected by chickpea farmer demographics and agronomic practices

To investigate the effects of agronomic practices and farmer demographics on levels of weed infestation in chickpea fields, a survey was conducted during 2015 in Sanjabi district, Kermanshah, Iran. Two sets of data were collected: (a) weed sampling from the selected chickpea fields, and (b) questionnaire recording of farmer demographics and agronomic management. The farmers were asked about their residence status (resident or migrant), occupation (farming only, farming plus a second job), experience and education levels, as well as seedbed preparation, sowing date and method, source of seed supply, crop cultivar, sowing seed rate, weed control operation and crop rotation history. The results showed that weed species composition was similar across the studied fields. The use of a row crop planter, a sowing rate of 45 kg ha^‐1, and weed control resulted in 30.2, 23.03 and 34.2% reductions in weed infestation compared with hand sowing, a sowing rate of 30 kg ha^‐1 and lack of weed control, respectively. Weed density decreased with increasing farmer experience and decreased by 33.0% and 23.5% in chickpea fields of resident farmers and owners whose sole occupation was agriculture. We found that 89.5% of the most experienced farmers adopted weed control operations and most resident landowners (77.4%) opted for crop planter (77.4%) and weed control (90.3%) compared to migrant farmers (50 and 68.5%, respectively). More landowners who were exclusively farmers performed weed control (90.6%) than owners who had a second job (67.9%).     

不同生育期转基因抗草甘膦抗虫棉花对草甘膦的耐受性

为明确转基因抗草甘膦抗虫棉田草甘膦的使用适期,于棉花子叶期、3~4片真叶期和花铃期喷施不同浓度的草甘膦,比较药害发生情况、棉花产量和纤维品质。棉花子叶期、3~4片真叶期和花铃期喷施1 640~9 840 g/hm²(有效成分,下同)草甘膦后,施药初期棉花均表现出一定的药害症状,药后4~8 d药害株率和药害指数达最大值,药后12 d药害症状逐渐减轻或消失。棉花子叶期和3~4片真叶期喷施草甘膦,对棉花产量无显著影响,但棉花花铃期喷施2 460~9 840 g/hm²草甘膦后,棉花产量显著降低,降幅达35.0%~63.3%。3个时期喷施草甘膦均不影响棉花的纤维品质。研究表明,转基因抗草甘膦抗虫棉田草甘膦的使用适期为棉花苗期。     

Chemical,Physical and Cultural Control of <Emphasis Type="Italic">Prostephanus truncatus</Emphasis>

Since its introduction into Africa 25 years ago, approaches to the management of the larger grain borer at farm level have gone through many changes. This article reviews the literature on chemical and non-chemical protection of maize and cassava after harvest from the perspective of the small-scale farmer during this period. The influence of traditional store design on Prostephanus truncatus and the history of changes in the use of post-harvest chemicals are described. Synthetic and non-synthetic chemicals, host plant resistance, store design, fumigation, plant products, inert dusts and thermal disinfestation all have a role to play. Attention is also given to the ways in which farmers in sub-Saharan Africa coped with the introduction of and damage caused by Prostephanus truncatus. Given the expense, poor distribution and health concerns of the use of synthetic chemicals, emphasis should be placed on the integration of low cost and low impact methods that could provide adequate control of this important post-harvest pest.     

IPM in developing countries: the danger of an ideal

This paper examines the evolution of integrated pest management (IPM) into the dominant paradigm in crop protection. The driving forces behind the development and adoption of IPM are explored and the conditions under which successful IPM has been practised are outlined. Repeated calls for the adoption of IPM in international agricultural research, extension and resource-poor farming are questioned in respect of claims made by IPM proponents. When examined, it becomes apparent that IPM per se is not a panacea for solving the problems faced by resource-poor farmers. Further investigation into the social, political, economic and ecological parameters associated with the development and implementation of IPM shows that is can work under certain conditions. However, the situation of most resource-poor farmers does not match the necessary criteria for the implemetation of IPM programmes. Viewed thus, it could be argued that IPM is more a vehicle for the continued transfer of technologies developed in response to the pressures exerted by argibusiness rather than a truly farmer first approach to solving the contraints facing the lives of resource-poor farmers in developing countries     

基于PRA的新疆三工河流域农户土地利用差异研究

采用参与式调查方法(PRA),对新疆三工河流域农户进行实地调查,研究三工河流域农户土地利用现状,对比分析不同条件下农户土地利用差异的形成原因。结果表明:1)低收入农户种植多样性相对较小,中等收入和高收入农户种植多样性较大。非农收入比例越小的农户多选择多元化种植,比例越大越趋向于单一化种植。2)地块规模越大越趋向于单一化种植,地块规模越小越趋向于多元化种植。土地综合质量较差时,农户多选择种植抗旱抗碱的作物;土地综合质量较好时,农户多选择高附加值的经济作物。3)土地体制不同,导致农户土地经营自主权和选择作物种类不同。4)由于种植习惯、土质以及水资源的差别,上中下游种植作物不尽相同,亩均耗水费也有差异。最后讨论了非农收入比例出现理论值之外值的情况以及兵地不同体制对农户土地利用差异的影响,以期更进一步了解三工河流域的农户土地利用差异及其产生原因。     

我国施药机械与施药技术现状及对策

我国农作物病虫草鼠每年需要化学防治面积达3亿公顷次以上,使用农药100万吨(制剂)左右,喷洒这些农药最主要和最基本手段还是靠施药机械,而目前广大农民广泛使用的主要是中小型施药机械,质量普遍不高,施药技术也比较落后,农药浪费和污染严重。本文系统地介绍了目前施药机械与施药技术的现状与问题,并从实际出发,提出了新农村需要新的喷雾器这一命题,同时提出了推进施药机械与施药技术工作的对策与建议。