Challenges to using neem (Azadirachta indica var. sianensis Valenton) in Thailand

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.     

Isolation and characterization of microsatellite markers in Indian neem (Azadirachta indica var. indica A. Juss) and cross-amplification in Thai neem (A. indica var. siamensis Valenton)

We developed eight polymorphic microsatellite loci in Indian neem (Azadirachta indica var. indica) and cross-amplified in closely related species Thai neem (A. indica var. siamensis). The number of alleles per locus in Indian neem and Thai neem ranged from 3 to 9 and 3 to 9, respectively. Average observed and expected heterozygosities in Indian neem and Thai neem were 0.63 and 0.70 and 0.61 and 0.65, respectively. Two loci exhibited significantly fewer heterozygotes than expected under Hardy–Weinberg equilibrium. These microsatellites may provide a useful tool for population genetics to establish conservation and management strategy.     

Field evaluation of the efficacy of neem oil (Azadirachta indica A. Juss) and Beauveria bassiana (Bals.) Vuill. in cotton production

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.     

Evaluation of neem, Azadirachta indica, with and without water management, for the control of culicine mosquito larvae in rice-fields

Applications of neem, Azadirachta indica (Meliaceae), to rice-fields were evaluated with the dual objective of controlling the culicine mosquito vectors of Japanese encephalitis virus (JEV) and enhancing the grain yield. Since crude neem products deteriorate under improper storage conditions, a laboratory bioassay was developed to screen neem cake powder against mosquito larvae, Culex quinquefasciatus. Only samples of neem giving over 90% bioassay mortality were used in field trials. When good quality neem cake powder was applied at the dose of 500 kg/ha, either alone or coated over urea, there was a striking reduction in the abundance of late instar culicine larvae and pupae. Only fourteen pupae were obtained over a period of 13 weeks in neem cake powder treated plots, and four in those treated with neem coated urea, compared with 101 in control plots. Both treatments were significantly less than the control, but on par with one another. In another field trial, neem cake coated urea was tested at 500 and 250 kg neem/ha in combination with water management practices. No reduction in efficacy was noted at the lower dose. Larval abundance in plots under water management alone did not differ significantly from the controls, but was significantly reduced when water management was combined with neem products. Two stable formulations, 'Neemrich-I' (lipid rich) and 'Neemrich-II' (azadirachtin rich), also gave good suppression of immature culicines. All the treatments with neem also gave higher grain yield than the control.(ABSTRACT TRUNCATED AT 250 WORDS)     

加强森林经营,实现森林保护与木材供应双赢

中国森林目前面临木材自给和生态安全的严重挑战.我国用1.2×108 hm2耕地养活了13亿人口,能否用2×108 hm2森林提供13亿人的用材,实现木材基本自给和森林保护的"双赢"?本文在分析我国林业的基本形势和实现木材自给必要性的基础上,从生产潜力和技术方面论证了实现木材自给和生态服务双赢的可能性.认为只要坚持以"森林经营"为核心,以培育稳定健康的森林生态系统为目标,以模拟森林的自然过程为手段重建森林生态系统,科学编制和执行森林经营规划,并加强林区基础建设和完善相应的林业政策,中国完全有可能实现生态保护与木材自给的"双赢".     

经济开发区生态规划与建设研究

生态规划和建设是协调经济发展和生态环境关系,创造和谐的人工化环境的调控对策。木文研究了沈阳开发区生态规划和建设的理论、方法,着重探讨了开发区经济、环境协调发展的途径:1)选择理想的协调发展优化方案,2)控制发展热电生产,发展集中供热和低能耗高技术产业,3)节约水资源,提高水循环利用率,4)在生态学原理指导下进行生态管理。     

Mycorrhizal inoculation in neem (Azadirachta indica) enhances azadirachtin content in seed kernels

In view of the high mycorrhizal dependency of neem trees (Azadirachta indica), an experiment was conducted to study if Arbuscular Mycorrhizal (AM) inoculation can enhance the azadirachtin content in seed kernels of trees grown in the field. Azadirachtin is an important active ingredient in neem seed kernels based on which a large biopesticide industry has emerged in India and few countries in Europe and the USA. Inoculation of neem seedlings in the nursery with Glomus fasciculatum and Glomus mosseae resulted in increased height, dry weight, root colonization and phosphorus (P) content. In a separate experiment, field-grown neem plants inoculated in the nursery and during transplantation with Glomus fasciculatum were evaluated after 5 years. No significant differences were found in the tree height, girth at breast height (GBH) and fruit yield but oil percentage, total triterpenoids and azadirachtin content in kernels increased significantly as a result of AM inoculation. A similar enhancement in azadirachtin was noted with P application. These results open up possibilities of producing quality neem seed with high bioactive ingredients through AM inoculation.     

Neem (Azadirachta indica a. Juss) components: candidates for the control of Crinipellis perniciosa and Phytophthora ssp

Witches' broom and pod rot are the two most devastating diseases of cocoa in South America and Africa, respectively. Their control by means of phytosanitation and chemical fungicides is labor-intensive, costly and, in many cases, environmentally undesirable. Therefore efforts are made in order to identify alternative, environmentally safe and cost-efficient methods for the control of these pathogens. Promising candidates are components of the neem tree (Azadirachta indica), that have been used for centuries in Asia as insecticides, fungicides, anticonceptionals in popular medicine. Here we report about tests on the effect of various concentrations of extracts from neem leaves on growth of mycelia of Crinipellis and Phytophthora and on germination of spores of Crinipellis. We show a 35% growth reduction of mycelia of Phytophthora on neem leaf extract media, whereas growth of mycelia of Crinipellis was not affected, even at the highest concentration of neem leaf extracts used (35%). However, the most dramatic effect of neem leaf extracts is observed on Crinipellis spore germination, here the extracts (20-35%) reduced germination almost completely. Based on these results, we believe that the neem tree might be a source for the production, on small and medium scale, of an effective and cheap formulation for the control of Crinipellis and Phytophthora.     

Integrated approach for the management of Meloidogyne javanica on eggplant using oil cakes and biocontrol agents

Investigations were carried out to evaluate the efficacy of biocontrol agents (Paecilomyces lilacinus and Cladosporium oxysporum) and/or oil cakes of castor, linseed, groundnut, mahua and neem in the management of root knot nematode, Meloidogyne javanica infecting eggplant under glasshouse conditions. All the treatments effectively suppressed the nematode population and kept the infection at significantly low level. Individual treatment of P. lilacinus was more effective than C. oxysporum in controlling M. javanica, whereas among oil cakes individual treatment of neem was more effective in the management of M. javanica followed by linseed cake, castor cake, groundnut cake and mahua cake. However, the efficacy of biocontrol agents increased in the presence of oil cakes. The highest improvement in plant growth and best protection against M. javanica was obtained by the integration of P. lilacinus with groundnut cake followed by neem cake, linseed cake, castor cake and mahua cake. On the other hand the integration of C. oxysporum with neem cake followed by groundnut cake, linseed cake, castor cake and mahua cake gave the best results in managing M. javanica on eggplant.     

Development of combined use of neem (Azadirachta indica) and water management for the control of culicine mosquitoes in rice fields

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.     

An endophytic fungus from <Emphasis Type="Italic">Azadirachta indica</Emphasis> A. Juss. that produces azadirachtin

Azadirachtin A and its structural analogues are a well-known class of natural insecticides having antifeedant and insect growth-regulating properties. These compounds are exclusive to the neem tree, Azadirachta indica A. Juss, from where they are currently sourced. Here we report for the first time, the isolation and characterization of a novel endophytic fungus from A. indica, which produces azadirachtin A and B in rich mycological medium (Sabouraud dextrose broth), under shake-flask fermentation conditions. The fungus was identified as Eupenicillium parvum by ITS analysis (ITS1 and ITS2 regions and the intervening 5.8S rDNA region). Azadirachtin A and B were identified and quantified by LC-HRMS and LC-HRMS², and by comparison with the authentic reference standards. The biosynthesis of azadirachtin A and B by the cultured endophyte, which is also produced by the host neem plant, provides an exciting platform for further scientific exploration within both the ecological and biochemical contexts.     

Effects of neem seed derivatives on behavioral and physiological responses of the Cosmopolites sordidus (Coleoptera: Curculionidae)

Both in a choice and multi-choice laboratory tests, fewer adults of the banana root borer, Cosmopolites sordidus (Germar), settled under the corms of the susceptible banana "Nakyetengu" treated with 5% aqueous extract of neem seed powder or cake or 2.5 and 5% emulsified neem oil than on water-treated corms. Feeding damage by larvae on banana pseudostem discs treated with 5% extract of powdered neem seed, kernel, or cake, or 5% emulsified neem oil was significantly less than on untreated discs. The larvae took much longer to locate feeding sites, initiate feeding and bore into pseudostem discs treated with extract of powdered neem seed or kernel. Few larvae survived when confined for 14 d on neem-treated banana pseudostems; the survivors weighed two to four times less than the larvae developing on untreated pseudostems. Females deposited up to 75% fewer eggs on neem-treated corms. In addition, egg hatching was reduced on neem-treated corms. The higher the concentration of neem materials the more severe the effect.     

The Integrated Effect of the Nematode-Bacteria Complex and Neem Plant Extracts Against Plutella Xylostella (L.) Larvae (Lepidoptera: Yponomeutidae) on Chinese Cabbage

The compatibility of the nematode-bacteria complex of Steinernema carpocapsae, Steinernema abbasi, and Heterorhabditis bacteriophora with neem plant extracts (seeds and leaves) to control diamondback moth, Plutella xylostella (L.) on Chinese cabbage plants was investigated under laboratory conditions. The initial treatment of Chinese plant leaves with neem plant extracts resulted in more susceptibility of P. xylostella to neem seeds extract than neem leaves extract. The combination studies resulted in a higher synergistic effect of nematode-bacteria complex of H. bacteriophora, S. abbasi and S. carpocapsae with neem seeds extract compared with that of S. abbasi with neem leaves extract. In contrast, the combination of nematode-bacteria complex of S. carpocapsae and H. bacteriophora with neem leaves extract gave an antagonistic effect. On the other hand, the time-mortality response was more reduced with neem seeds extract than with neem leaves extract, besides it was a concentration dependant factor. We conclude from these investigations that the combination of entomopathogenic nematodes with neem plant extracts could be of success in controlling P. xylostella on Chinese cabbage plants in the field.     

Neem components as potential agents for cancer prevention and treatment

Azadirachta indica, also known as neem, is commonly found in many semi-tropical and tropical countries including India, Pakistan, and Bangladesh. The components extracted from neem plant have been used in traditional medicine for the cure of multiple diseases including cancer for centuries. The extracts of seeds, leaves, flowers, and fruits of neem have consistently shown chemopreventive and antitumor effects in different types of cancer. Azadirachtin and nimbolide are among the few bioactive components in neem that have been studied extensively, but research on a great number of additional bioactive components is warranted. The key anticancer effects of neem components on malignant cells include inhibition of cell proliferation, induction of cell death, suppression of cancer angiogenesis, restoration of cellular reduction/oxidation (redox) balance, and enhancement of the host immune responses against tumor cells. While the underlying mechanisms of these effects are mostly unclear, the suppression of NF-κB signaling pathway is, at least partially, involved in the anticancer functions of neem components. Importantly, the anti-proliferative and apoptosis-inducing effects of neem components are tumor selective as the effects on normal cells are significantly weaker. In addition, neem extracts sensitize cancer cells to immunotherapy and radiotherapy, and enhance the efficacy of certain cancer chemotherapeutic agents. This review summarizes the current updates on the anticancer effects of neem components and their possible impact on managing cancer incidence and treatment.     

Importance of soil-water relations in assessing the endpoint of bioremediated soils

This study was conducted during 1992–1994 under semi-arid conditions in Burkina Faso. Our aim was to assess the influence of different mulch materials on soil variables affecting crop growth; i.e. water content, nutrient contents and temperature. The grain yield of Sorghum bicolor was used as a bioindicator, i.e. as an integrated measure of mulch effects.Six treatments were tested, two of which were leaf mulches of special interest for agroforestry. The treatments were chosen to represent mulch materials differing in nutrient content and decomposability (assumed to influence the duration of the impact on soil water content and temperature). The treatments were as follows: (1) control (no addition), (2) Azadirachta indica (neem) leaves, (3) neem leaves + aerobic compost of sorghum straw, (4) aerobic compost, (5) Acacia holocericea (acacia) phyllodes, and (6) wild grass. The mulching rate was 5 t dry matter ha^-1, and base mineral fertilizers were applied to all plots.It was shown that the neem leaves, neem leaves + compost, wild grass and acacia phyllodes treatments all significantly influenced the soil by conserving water and reducing temperatures compared with the control or the treatment with compost alone. Plots treated with either neem leaves, neem leaves + compost or compost alone gave higher yields than the three other treatments, generally poorer in nutrients, between which there was little difference. Neem leaves gave the numerically highest response: 1.54 × control, corresponding to a grain yield increase of 554 kg dry mass ha^-1 yr^-1 when averaged over the three years of study.Thus, yields did not always increase in spite of increased soil moisture and decreased soil temperatures. It was concluded that nutrients were more limiting than water or high soil temperatures under the conditions studied. The highest yields were achieved with a mulch that combines high nutrient delivery with water conservation and temperature reduction, namely mulch from neem leaves.     

Seeing the forest for its multiple ecosystem services: Indicators for cultural services in heterogeneous forests

The ecosystem service (ES) framework is gaining traction in ecosystem management as a means to recognize the multiple benefits that ecosystems provide. In forested ecosystems, many structural attributes (trees, understory plants and woody debris) create heterogeneous ecosystems that provide numerous ecosystem services, including many that are culturally important. However, application of the ES framework to forest management is challenged by difficulties measuring and comparing multiple ES across diverse and heterogeneous forest conditions. Indicators can help bring the ES approach to forest management by providing a means for accurate ES inventory and mapping. We measured 10 forest ES in contrasting forest types to investigate the effects of past forest harvesting in coastal temperate rainforest of Vancouver Island, BC, Canada. Our objectives were to build a systematic set of ES indicators for coastal temperate forests based on forest structural features, including trees, coarse woody debris, and understory plants. To achieve this, we 1) analyzed field data to compare the effects of forest age (old-growth vs. second-growth) and ecological site conditions (riparian vs. upland forest) on the bundle of ES provided by different forest types; and 2) worked with a local indigenous wood carver to identify attributes of cedar trees (Thuja plicata) essential for traditional uses, including canoe carving. Forest age and forest type had significant and major effects on bundles of ES. Old-growth forests provided three times higher carbon storage, nine times higher wood volume, and eighteen times higher canopy habitat services than recovering forests. Within old-growth forests, the proportion of trees suitable for traditional indigenous wood carving was significantly higher in riparian stands. Yet of 456 trees measured, only 17 were cedar with potential traditional uses. Of those, trees for canoe carving were the least frequent (n = 3), which we identified as large (>110 cm DBH) trees of exceptional quality. In general, old-growth riparian forests were a hotspot of ES, providing for example nearly three times as much carbon storage as old-growth forests on upland sites and 12 times the amount of carbon storage as found in second-growth forests on upland sites. These results indicate that typical inventories of forest ES, which usually generalize across heterogeneity, may oversimplify dramatic variations in ES bundles in forested landscapes. Our novel set of stand-level ES indicators can improve the accuracy of ES assessments, incorporate important cultural ES, and help address the role of landscape heterogeneity in influencing ES.     

Toward Estimating Displaced Primary Production from Recycling: A Case Study of U.S. Aluminum

Recycling materials from end‐of‐life products has the potential to create environmental benefit by displacing more harmful primary material production. However, displacement is governed by market forces and is not guaranteed; if full displacement does not occur, the environmental benefits of recycling are reduced or eliminated. Therefore, quantifying the true “displacement rate” caused by recycling is essential to accurately assess environmental benefits and make optimal environmental management decisions. Our 2016 article proposed a market‐based methodology to estimate actual displacement rates following an increase in recycling or reuse. The current article demonstrates the operation, utility, and challenges of that methodology in the context of the U.S. aluminum industry. Sensitivity analyses reveal that displacement estimates are sensitive to uncertainty in price elasticities. Results suggest that 100% displacement is unlikely immediately following a sustained supply‐driven increase in aluminum recycling and even less likely in the long term. However, zero and even negative displacement are possible. A variant of the model revealed that demand‐driven increases in recycling are less likely than supply‐driven changes to result in full displacement. However, model limitations exist and challenges arose in the estimation process, the effects of which are discussed. We suggest implications for environmental assessment, present lessons learned from applying the estimation methodology, and highlight the need for further research in the market dynamics of recycling.     

Comparative laboratory toxicity of neem pesticides to honey bees (Hymenoptera: Apidae), their mite parasites Varroa jacobsoni (Acari: Varroidae) and Acarapis woodi (Acari: Tarsonemidae), and brood pathogens Paenibacillus larvae and Ascophaera apis

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.     

Evaluation of neem (Azadirachta indica L.) products for the control of root-knot nematode of chilli pepper (Capsicum annum L.)

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.     

Variations in fatty acid composition of neem seeds collected from the Rajasthan state of India

Neem (Azadirachta indica) is a multipurpose tree native to the Indian subcontinent and South-East Asian countries. Products derived from neem have been used for centuries, particularly in India, for medicinal and pest-management purposes. Azadirachtin and neem oil are the two major commercially important products derived from the tree. The oil contains palmitic, stearic, oleic and linoleic acids in good proportion. Although there is growing demand for quality planting material for plantation of neem, efforts are lacking for the selection of neem trees based on their biochemical composition. In the present study, 60 Neem seed samples were collected from different provinances of the Rajasthan state in India. These samples were analysed by GLC to study the variability of fatty acid composition. Significant variability in individual fatty acids was observed. The palmitic acid ranged from 16 to 34%, stearic acid from 6 to 24%, oleic acid from 25 to 58% and linoleic acid from 6 to 17%. This variability can be exploited for selection of trees and for studying the genetic variability in neem. These selections can also be utilized for genetic improvement of the tree.