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1.
The use of botanical insecticides based on the neem seed (Azadirachta indica var.siamensis Valeton) shows strong potential in the fight against important agricultural pests. Unfortunately, its use in rural Thailand is extremely limited. This study examines the efficacy of neem extracts processed under rural conditions; identifies factors that influence local farmers’ adoption of neem products; and proposes recommendations to promote the use of neem insecticides. The principal findings are: in field trials conducted under typical rural conditions, neem did not adequately control major pests of yard-long beans (Vigna sesquipedalis); and intensity of vegetable production, knowledge of neem insecticides and availability and accessibility of neem products strongly influence farmers’ adoption of neem products for pest control.  相似文献   

2.
The neem tree (Azadirachta indica) contains promising pest-control substances found effective against many economically important pests. These materials are easy to process by village-level industries and easy to use by limited-resource farmers, thereby offering potential for crop protection and off-farm income generation. The tree’s numerous pharmacological and other complementary uses make it doubly attractive for incorporation in large-scale rural development efforts.  相似文献   

3.
Philippine vegetable farmers commonly use synthetic insecticides to control insect pests on yardlong beans ( Vigna unguiculata ssp. sesquipedalis ). An important pest on yardlong beans is the cowpea aphid, Aphis craccivora Koch. Overuse of chemical insecticides and the adverse consequences for farmer health and for the environment have been reported. The natural enemies of A. craccivora , such as the coccinelidae beetle, Menochilus sexmaculatus (Fabr.), do not provide economic control on their own. In the present study the efficacy of the biological insecticide neem (both commercial and homemade) alone, and in combination with diatomaceous earth against A. craccivora was evaluated. The same insecticides were also examined to investigate their deleterious effect on M. sexmaculatus . The efficacies of different treatments with biological insecticides were compared with the use of the synthetic insecticide Hostathion (triazophos). Experiments were conducted under Philippine lowland conditions during the dry season when the occurrence of pest problems in yardlong beans is very great. Commercial neem, NeemAzal-T/S (Trifolio-M GmbH, Lahnau, Germany), significantly reduced the number of A. craccivora . NeemAzal-T/S and diatomaceous earth in combination produced the best control of A. craccivora and were less toxic to M. sexmaculatus than treatment with Hostathion (triazophos). Aqueous homemade neem solution did not control the A. craccivora populations.  相似文献   

4.
Yam is an important crop which serves as a source of income to small-holder farmers as well as a foreign exchange earner. Among the constraints faced by yam farmers are pests and diseases, especially deterioration caused by microbes during storage. Since over dependence on pesticides is being discouraged, neem seed and ginger extracts were evaluated as potential control agents against rot-causing fungi. The study was conducted in the Spanish laboratory, at the Faculty of Agriculture, University for Development Studies, Nyankpala Campus. Isolations were made from rotted yam tubers sampled from the Tamale Central market with potato dextrose agar (PDA) as the growth medium. Growth inhibition of the isolates was determined by growing pure cultures on PDA plates amended with 2?ml each of ethanol and aqueous extracts of neem seed and ginger as well as carbendazim. A pathogenicity test proved that Aspergillus flavus, A. niger, A. ochraceus and Penicillium digitatum isolated from the rotted tubers were responsible for the rot. A. niger had a significantly higher (p?<?0.05) occurrence (40%) than the others. Growth inhibitions by carbendazim and ethanol extracts of neem seed and ginger were comparable but significantly higher (p?<?0.05) than the aqueous extracts of neem seed and ginger as well as the control. However, the aqueous extracts of neem seed and ginger had a significantly higher (p?<?0.05) inhibition than the control. For instance, growth inhibition of A. niger by carbendazim, ethanol neem seed and ginger extracts were 70.5, 69.6 and 65.5%, respectively, while inhibition by aqueous neem seed and ginger extracts were 33.9 and 24.8%, respectively. Since aqueous extracts of neem seed and ginger significantly inhibited (p?<?0.05) growth of the rot-causing fungi, they can be used as surface protectants of stored tubers.  相似文献   

5.
Laboratory bioassays were conducted to evaluate neem oil and neem extract for the management of key honey bee (Apis mellifera L.) pests. Neem pesticides inhibited the growth of Paenibacillus larvae (Ash, Priest & Collins) in vitro but had no effect on the growth of Ascophaera apis (Olive & Spiltoir). Azadirachtin-rich extract (neem-aza) was 10 times more potent than crude neem oil (neem oil) against P. larvae suggesting that azadirachtin is a main antibiotic component in neem. Neem-aza, however, was ineffective at controlling the honey bee mite parasites Varroa jacobsoni (Ouduemans) and Acarapis woodi (Rennie). Honey bees also were deterred from feeding on sucrose syrup containing > 0.01 mg/ml of neem-aza. However, neem oil applied topically to infested bees in the laboratory proved highly effective against both mite species. Approximately 50-90% V. jacobsoni mortality was observed 48 h after treatment with associated bee mortality lower than 10%. Although topically applied neem oil did not result in direct A. woodi mortality, it offered significant protection of bees from infestation by A. woodi. Other vegetable and petroleum-based oils also offered selective control of honey bee mites, suggesting neem oil has both a physical and a toxicological mode of action. Although oils are not as selective as the V. jacobsoni acaricide tau-fluvalinate, they nonetheless hold promise for the simultaneous management of several honey bee pests.  相似文献   

6.
植物保护剂防治害虫效果的评价方法   总被引:76,自引:20,他引:76  
在以作用因子组建的生命表和干扰作用控制指数(IIPC)的基础上建立植物保护剂的研究方法和综合评价指标,以表示驱避成虫选择寄主,干扰成虫的产卵行为,对卵孵化的影响,以及干扰幼虫的行为,包括逃避、拒食、幼虫特别是初孵幼虫中毒死亡的作用.采用所建立的研究方法和评价指标的试验结果表明,菜田附近大多数非寄主植物的乙醇抽提物(干重1g·100ml-1)如大叶桉(Eucalytusrubusta)、蟛蜞菊(Wedeliachinensis)等对保护十字花科蔬菜免受小菜蛾为害起着明显的作用.印楝油对小菜蛾幼虫的防治效果相当显著.机油乳剂(CALTEX产品)对桔全爪螨具有明显的控制效果  相似文献   

7.
Chilli pepper is an important vegetable in the diet of Ghanaians but there are some constraints militating against increased production notable among which is nematode infestation. A study was therefore carried out at the plant house of the Faculty of Agriculture, University for Development Studies, Nyankpala to investigate the efficacy of neem products against root-knot nematode of chilli pepper (Capsicum annum L.). The treatments which included 20 g neem leaf powder, 20 g neem cake, 20 g neem seed powder and control were arranged in a completely randomised design with four replications. Neem products significantly reduced (p < 0.05) nematode population, with 20 g of neem leaf powder recording the highest reduction. Similarly, plants treated with neem leaf powder produced a significantly lower (p < 0.05) number of root galls compared to the other treatments. Neem leaf powder could be used as a nematicide for nematodes control as a replacement for synthetic nematicides.  相似文献   

8.
在以作用因子组建的生命表和干扰作用控制指数(IIPC)的基础上建立植物保护剂的研究方法和综合评价指标,以表示驱避成虫选择寄主,干扰成虫的产卵行为,对卵孵化的影响,以及干扰幼虫的行为,包括逃避、拒食、幼虫特别是初孵幼虫中毒死亡的作用.采用所建立的研究方法和评价指标的试验结果表明,菜田附近大多数非寄主植物的乙醇抽提物(干重1g·100ml-1)如大叶桉(Eucalytus rubusta)、蟛蜞菊(Wedelia chinensis)等对保护十字花科蔬菜免受小菜蛾为害起着明显的作用.印楝油对小菜蛾幼虫的防治效果相当显著.机油乳剂(CAL TEX产品)对桔全爪螨具有明显的控制效果.  相似文献   

9.

Fusarium wilt and root-knot are important diseases of tomato. The use of chemical is becoming less appealing because of the health implications. Also, the chemicals required are often not within the reach of farmers in most of the developing part of the world. This research is aimed at finding an alternative mode of control. Tomato variety Roma VF inoculated with Meloidogyne and Fusarium were treated with 2 g/kg soil neem seed powder in the screenhouse and 2 Mg ha ? 1 in the field. An untreated and Furadan treated plot in the field served as control. Neem seed powder significantly reduced the disease severity of Fusarium and root-knot in both screenhouse and field. Results suggest the possible use of neem seed powder for control of the root-knot nematodes - Fusarium wilt disease complex.  相似文献   

10.
Neem oil (Azadirachta indica A. Juss) alone and combined with the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (isolate Bb11) was applied to control cotton pests. The efficacy of these treatments was compared with that of synthetic insecticides applied either in a calendar‐based application or in the ‘Lutte Etagée Ciblée’ (LEC) strategy, consisting of using first calendar‐based (half‐dose) applications followed by threshold‐based treatments. The experiment was carried out in collaborative research with farmers in three cotton agro‐ecological zones differing in rainfall, pest prevalence, and farming practices. The neem oil and neem oil‐Bb11 treatments required 2 to 6 applications, while conventional and LEC received 6 to 8 applications. The percentage of damaged reproductive organs in plots treated with neem oil and neem oil plus Bb11 was higher than that recorded under the conventional and LEC strategy, with exception of the zone with the highest rainfall; this resulted in yields being 25% and 39% lower, respectively. Yields in the biopesticide plots were 26–42% higher and in the conventional and LEC plots 44–59% higher than those in the control plots that received only water. Overall, the LEC regime scored best, both in yield and profitability. The incidence of natural enemies was highest in the control and in the plots treated with biopesticides. Although the use of entomopathogen Bb11 and neem oil avoids many problems associated with the application of synthetic insecticides, their efficacy needs to be enhanced by improved formulation or by combining them with other pesticides.  相似文献   

11.
Ethnoecological knowledge may be understood as spontaneous knowledge, culturally referenced of any society's members, learned and transmitted through social interactions and that are targeted at resolution of daily routine situations. The traditional knowledge in small scale economy societies as well as the non-academic knowledge in urban-industrial societies might be included in this concept. An ethnoecological approach study was performed here on people living at the communities of Alvinho, Almeida, Chã do Marinho, Floriano, and Chã de Oiti, all located in the municipality of Lagoa Seca, Paraíba state, Northeast Brazil. The general objective pursued here was to study the knowledge that peasant farmers have on management of plant species utilized for pest control. For this, the methodological instruments employed here to investigate the ethnoecological knowledge were: direct observation, structured and semi-structured interviews, and tours conducted by local peasant farmers. We analyzed the data obtained under an emic/etic view and also by comparing the local knowledge with those obtained from the literature. The results showed that people in those communities utilize management alternatives for controlling pests, which are mainly: (i) fallowing; (ii) crop rotation; (iii) destruction of crop remains and fruits attacked by pests; (iv) alternations of crops with repellent plants; and/or (v) mixed cropping; (vi) insect's larvae covered with soil; (vii) crops irrigated abundantly; and (viii) soil preparation. The recovery and comprehension we get about this knowledge as well as the farmers' savoir faire, are extremely important to the revival of ancient agricultural practices, which have been forgotten due to advances in modern agriculture. The data obtained here showed that a huge body of knowledge the farmers have on many forms or strategies of management are generally compatible with scientific knowledge.  相似文献   

12.
Plant extracts from the neem tree can be applied as a bioinsecticidal compound in ‘attract-and-kill’ co-formulations to control soil-dwelling insect pests. Since insects are attracted to the bioinsecticide, the attract-and-kill approach benefits from a reduced dose of insecticide needed. Here, we demonstrate that a powdery neem seed kernel extract in combination with corn starch significantly enhances the drying survival of co-encapsulated CO2-releasing Saccharomyces cerevisiae. Additionally, an increased content of the neem extract was shown to slow down the relative release of azadirachtin A. Both findings are of high relevance for the development of formulations in the field of biological pest control.  相似文献   

13.
Being the ultimate beneficiary of ecosystem services provided by on-farm agricultural biodiversity, the participation of farmers in its sustainable utilization and conservation is crucial. How much aware they are with the significance and conservation of agricultural biodiversity in order to improve their crop yield remains unclear, especially from the developing courtiers. Pollination is one of such ecosystem services, enormously contributed by the wild bees. In the present study, we have investigated the knowledge of farmers about bees and pollination in general in three districts i.e. Multan, Bahawalpur and Khanewal of southern Punjab, Pakistan. Some 300 farmers (100 cucurbit growers in each district using convenient sampling method) were interviewed using a semi-structured questionnaire. Respondents were first presented with a box of insect specimens and then were asked to identify bees among those. Those who identified correctly were asked to state about their nesting sites. Only 11% of the respondents could correctly identify the bees and half of them could report something about nesting sites. A majority (63%) of the farmers was unable to tell fertilization requirements in cucurbits, 59% could not distinguish female flower from the male flower and 64% could not state any benefit of bees. However, upon briefing about the significance of bee pollinators, 58% of the farmers showed eagerness to conserve bees at their farms. Keeping in view the inadequacies of farmers' knowledge about wild bees and pollination in general, the present study also gives some policy recommendations.  相似文献   

14.
The effect of an integrated pest management (IPM) package, host plantresistance, Chrysoperla carnea predation and neem oil wereevaluated against the spider mite Tetranychus ludeni oneggplant(Solanum melongena L.) fields in 1996 and 1997, byestimating the mite population density and yield levels. Compared with the IPMpackage (Panruti local, C. carnea plus neem oil), thestandard (susceptible) eggplant variety (MDU1) grown by farmers andtreated with an acaricide (dicofol) had significantly higher mite densities.Thepredator C. carnea was recorded in significantly lowernumbers in plots with the standard variety compared to a resistant variety(panruti local) with the full IPM package. Eggplant yield level and crop valuewere highest in the IPM-treated plots followed by Panruti local plusC. carnea. The standard variety treated with an acaricidehad the lowest yield and value. These results indicated the usefulness of hostplant resistance complemented by biorational control agents, such asC. carnea and neem oil, that these are suitable componentsin an IPM programme for managing the spider mite in endemic areas.  相似文献   

15.
16.
We describe the results of a survey of farmers’ perceptions of and satisfaction with the performance of watershed development activities on socioeconomic, agriculture and livestock, and environmental attributes. We administered a questionnaire to 120 farmers randomly interviewed in the Morni Hill area of the Siwalik Himalayas in India. Our results show that the farmers have considerable knowledge about the implementation of watershed development activities and their impact on the economy, agriculture and the environment. Our respondents generally agreed or strongly agreed with most investigated parameters, with a few exceptions such as employment opportunities in the dairying sector, rise in panchayat funds, milk production, fuel wood availability, grazing lands and use of mechanical inputs in agriculture. Water availability has resulted in a positive change in the cropping pattern, which has shifted to more remunerative crops, such as paddy, pulses, vegetables and high yielding wheat. Approximately 45 % of respondents were highly satisfied with the results of the watershed development activities. The overall level of satisfaction pertaining to different socioeconomic, agriculture and livestock, and environmental parameters was approximately 56 %, which reveals that respondents are well aware of the impacts of the watershed development activities. Therefore, we suggest that farmers’ perceptions could usefully be incorporated into decision-making processes for targeting land and water management interventions.  相似文献   

17.
Cereals are staple food for many countries and are grown on millions of hectares of land, but much of the harvest is wasted due to losses by pests. To minimize these losses, many pesticides are used which are damaging to the environment and human health. There are debates to get rid of these chemicals but they are still in use at large scale. An alternative control strategy for insect pests in storage houses is the use of botanicals. In this study, four plant essential oils, two plant extracts, two herbicides, and two insecticides were used against Tribolium confusum and the comparison of toxicity was made by calculating LC50 and LT50 values. LC50 values were higher for abamectin (2.09–10.23 mg/L) and cypermethrin (3.41–11.78 mg/L) insecticides followed by neem essential oil (7.39–19.24 mg/L) and citrus extract (10.14–24.50 mg/L). However, LC50 values were maximum in case of jaman plant extract (22.38–176.42 mg/L) followed by two herbicides, Logran (19.66–39.72 mg/L) and Topik (29.09–47.67 mg/L) However, LC50 values were higher for topic herbicide (24.098 ppm) and jaman essential oil (16.383 ppm) after four days of treatment. Abamectin and cypermethrin insecticides, neem essential oil and citrus plant extract also killed adults of T. confusum quicker as compared other essential oils, extracts and herbicides. Results revealed that botanical formulations being environmentally safe could be used instead of highly hazardous pesticides for stored products’ pests. This study also elaborates the non-host toxicity of herbicides commonly applied in our agroecosystem.  相似文献   

18.
Abstract. Crude neem products have earlier shown considerable promise for control of culicine mosquito vectors in rice fields as a by-product of their agricultural use as fertilizers, but suffer from disadvantages of bulkiness and lack of stability in storage. Relatively stable lipid-rich fractions of neem were shown to be as effective as good-quality crude neem products in control of breeding of culicine vectors of Japanese encephalitis, and also produced a slight but significant reduction in populations of anopheline pupae. Neem-based formulations coated over urea significantly increased grain yield, but used alone did not, whereas combining the use of neem-coated urea and water management by intermittent irrigation had a greater effect on grain yield than that of water management alone. The neem fractions were relatively cost-effective, and the combined water management and neem-coated urea strategy is acceptable to farmers, who are already aware of the benefits of the use of neem-coated urea, and of water management. This technology therefore has considerable promise as an environmentally benign method of rice-field mosquito control that could be sustainably implemented by farmers.  相似文献   

19.
There are fewer than 162 ha of commercial Chinese chestnut orchards in the United States, with approximately half of these in the Southeast. Large numbers of Chinese chestnut seedlings are planted annually in the United States for home and game food production; however, knowledge about chestnut propagation, fertilization, pests, harvest, storage and marketing is not adequate. There is little commercial marketing of U.S.-grown Chinese chestnuts through roadside markets and local farmers’ markets as the supply is low and unpredictable. However, we yearly import 4.5 mill kg of European chestnuts to satisfy the U.S. market. Successful chestnut orchards will require vegetatively propagated selections, intensive management, mechanical harvesting, and control of insect and disease pests.  相似文献   

20.
In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug.  相似文献   

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