Showing papers on "Azadirachta published in 1986"
188 citations
TL;DR: The neem tree (Azadirachta indica) contains promising pest-control substances found effective against many economically important pests, thereby offering potential for crop protection and off-farm income generation.
Abstract: 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.
86 citations
63 citations
TL;DR: Deacetylazadirachtinol was found to be as potent as azadirachin in the inhibition of insect ecdysis when fed in artificial diet to larvae of the tobacco budworm.
43 citations
TL;DR: Solvent-free extracts obtained from the leaves of Azadirachta indica and Pisum sativum were screened for antimalarial action using Plasmodium berghei in mice and found to have significant prophylactic activity.
38 citations
TL;DR: The aqueous leaf extract of Azadirachta indica substantially inhibited NADPH cytochrome C(P-450) reductase activity in rats with a significant increase in the microsomal protein.
36 citations
TL;DR: Two new bitter meliacins, nimocinolide (1) and isonimocINolide(2), have been isolated from the fresh leaves of Azadirachta indica(neem) as discussed by the authors, which acted as insect growth regulators against houseflies (Musca domestica) and mosquitoes (Aedes aegypti).
Abstract: Two new bitter meliacins, nimocinolide (1) and isonimocinolide (2), have been isolated from the fresh leaves of Azadirachta indica(neem). A new meliacin, nimocin (6) has further been isolated from its fresh fruits along with the known azadirone, gedunin, epoxyazadiradione, 7-deacetyl-7-benzoylazadiradione, azadiradione, 17-hydroxyazadiradione, and β-sitosterol. The structures of these tetranortriterpenoids were elucidated through chemical and spectral studies. Compounds (1) and (2) acted as insect growth regulators against houseflies (Musca domestica) and mosquitoes (Aedes aegypti).
32 citations
TL;DR: The structure of deacetylazadirachtinol (2) has been reassigned as 3-tigloylazadrachtol (3) on the basis of a detailed 1H and 13C n.m. spectroscopic analysis as mentioned in this paper.
Abstract: The structure of deacetylazadirachtinol (2) has been reassigned as 3-tigloylazadirachtol (3)(tigloyl = 2-methylcrotonoyl) on the basis of a detailed 1H and 13C n.m.r. spectroscopic analysis.
28 citations
TL;DR: In the range of 1–8 μg/g azadirachtin caused reduction in body weight which was, in general, dose dependent, and even the highest dose failed to induce absolute feeding inhibition.
Abstract: Azadirachtin, a compound from seed kernels of the neem tree, Azadirachta indica A. Juss was tested at 2 μg/g for its effect on development, food consumption and utilization and haemolymph constituents of final instar Schistocerca gregaria. The effective dose in causing 50% moult inhibition (ED50) was 1.66 μg/g. In the range of 1–8 μg/g azadirachtin caused reduction in body weight which was, in general, dose dependent. Even the highest dose failed to induce absolute feeding inhibition.
Some of the azadirachtin treated nymphs survived beyond 40 days without moult and those attempted to moult after the normal moulting period (16–18 days) generally died during ecdysis. It significantly reduced the rate of feeding, growth and utilization of food to body matter in both sexes. Its effect on females was more drastic as they showed negative growth rate revealing the catabolic state. Maximum changes in haemolymph protein and amino acid levels were observed particularly in females between 5th and 8th day after treatment.
Zusammenfassung
Veranderung der Entwicklung, Nahrungsausnutzung und Hamolymphe von Schistocerca gregaria Forsk. unter dem Einflus von Azadirachtin
Azadirachtin, eine Komponente der Samen des Neem-Baumes, Azadirachta indica A. Juss wurde in einer Dosis von 2 μg/g auf seine Wirkung auf die Entwicklung, Ernahrung und Hamolymphe der alten Larven von S. gregaria untersucht. Die wirksame Dosis zur Erzeugung von 50% Hautungsverhinderung (ED50) betrug 1,66 μg/g. Im Bereich zwischen 1 und 8 μg/g verursachte Azadirachtin eine Verringerung des Korpergewichtes, die im allgemeinen Dosis-abhangig war. Selbst die Hochstdosis verhinderte die Nahrungsaufnahme nicht ganz. Einige der mit Azadirachtin behandelten Nymphen lebten mehr als 40 Tage ohne sich zu hauten, und jene, die sich zu hauten versuchten, starben dabei im allgemeinen ab. Azadirachtin verringerte signifikant die Fras-und Wachstumsrate sowie die Ausnutzung der Nahrung bei beiden Geschlechtern. Seine Wirkung auf die Weibchen war deutlicher als auf die Mannchen. Die starksten Veranderungen im Gehalt von Hamolymphe-Eiweis und -Aminosauren wurde bei Weibchen zwischen dem 5. und 8. Tag nach Behandlung festgestellt.
26 citations
TL;DR: Results indicate that both neem seed kernels and hot pepper fruit extracts have potentials in giving good protection of beans from insect pests; they are indigenous, safe and readily available to farmers in Tanzania.
Abstract: The effect of extracts from neem (Azadirachta indica A. Juss) seed kernels, neem leaves, tomato (Lycopersicon esculentum) leaves and hot pepper (Capsicum annuum) fruits on the incidence and damage of insect pests of common beans was investigated under field conditions. Aqueous extracts from neem seed kernels and hot pepper fruits caused general deterrent effects including antifeedant effect in foliar beetle Ootheca bennigseni, larvae of pod borers Maruca testulalis and Heliothis armigera and other important insect pests of beans. Plots treated with neem seed kernel and hot pepper fruit extracts were relatively less damaged and had a significant lower incidence of insect pests. Results indicate that both neem seed kernels and hot pepper fruit extracts have potentials in giving good protection of beans from insect pests; they are indigenous, safe and readily available to farmers in Tanzania.
Zusammenfassung
Zur Wirkung von Pflanzenextrakten auf schadliche Insekten an Bohnen
Es wurden unter Freilandbedingungen die Wirkungen von Extrakten aus Samen und Blattern des Neem-Baumes (Azadirachta indica A. Juss) und aus den Blattern der Tomate (Lycopersicon esculentum) sowie aus Fruchten der Paprika (Capsicum annuum) auf einige an Bohnen schadliche Insekten untersucht. Wasrige Extrakte von Neem-Samen und Paprikafruchten wirkten im allgemeinen abschreckend beim Blattkafer Ootheca bennigseni, bei Larven von Maruca testulalis und Heliothis armigera sowie bei anderen wichtigen Bohnenschadlingen. Versuchsflachen, die mit Neem- und Paprika-Extrakten behandelt waren, wurden relativ weniger geschadigt und von einer signifikant geringeren Zahl Insekten befallen. Die Ergebnisse zeigen, das sowohl Neem- als auch Paprika-Extrakte grundsatzlich imstande sind, Bohnen vor Schadinsekten zu schutzen. Sie sind fur die Farmer in Tansania verfugbar und ihre Handhabung ist sicher.
23 citations
TL;DR: Application of neem products like neem leaf and neem cake to wetland soil did not have any adverse effect on the population of heterotrophic microflora; nitrifying bacteria decreased significantly; it is suggested that neem Leaf could be used as an inhibitor of nitrification for enhancing nitrogen use efficiency of fertilizers where neam leaf is available in plentiful supply.
Abstract: Application of neem products like neem leaf and neem cake to wetland soil did not have any adverse effect on the population of heterotrophic microflora; nitrifying bacteria, on the other hand, decreased significantly due to addition of neem cake and fresh and dried neem leaf with urea. It is suggested that neem leaf could be used as an inhibitor of nitrification for enhancing nitrogen use efficiency of fertilizers where neem leaf is available in plentiful supply.
TL;DR: An Amino acid compositions are presented for the proteinaceous components of the gum exudates from Albizia glaberrima, A. sericocephala and A. anthelmintica, and the non-leguminous genera Aralia and Lannea have high proportions of hydroxyproline.
Journal Article•
TL;DR: Leaf spots though widespread did not cause much damage to seedlings, while the other diseases resulted in ca.
Abstract: Occurrence of four disease of foliage viz. two leaf spots, one leaf blight and a web blight caused by Colletotrichum capsici, Cercospora subsessilis, Sderotium rolfsii and Rhizoctonia solani respectively and one each of stem (stem rot by S. rolfsii) and root (wilt by Fusarium solani) are reported for the first time on seedlings of Azadirachta indica from Kerala, India. Leaf spots though widespread did not cause much damage to seedlings, while the other diseases resulted in ca. 20–30 percent mortality, thus affecting the stocking.
TL;DR: A new triterpenoid named nimbocinone, has been isolated from fresh, undried winter leaves of Azadirachta indica along with two sterols identified as sitosterol and stiginasterol, which is the first 26-hydroxytriterpenoid isolated from any part of the neem tree.
TL;DR: In this paper, the effects of volatile fractions (VF) of hydrodistillates of two medicinal plants, namely neem and blue-gum, on germination of sclerotia of Macrophomina phaseolina were more pronounced than non-volatile fractions (NVF).
Abstract: Deleterious effects of volatile fractions (VF) of hydrodistillates of two medicinal plants, namely neem ( Azadirachta indica ) and blue-gum ( Eucalyptus globulus ) on germination of sclerotia of Macrophomina phaseolina were more pronounced than non-volatile fractions (NVF). A notable decrease in sclerotial germination due to VF and NVF of neem oil and neem oil-cake extract was observed after 24 h incubation. Extracts of both the plants showed fungicidal effect against the pathogen, whereas neem leaf distillate had no such effect.
TL;DR: In this paper, a limonoid, nim bocinol, has been isolated from the fresh, undried, ripe fruits of Azadirachta indica (neem) along with known comonents, azadirone, epoxyazadiradione, azadiadione and cholesterol.
Abstract: Abstract A new limonoid, nim bocinol, has been isolated from the fresh, undried, ripe fruits of Azadirachta indica (neem ) along with known com ponents, azadirone, epoxyazadiradione, azadiradione, gedunin, 17-hydroxyazadiradione and cholesterol. It is the first report of the isolation of cholesterol from any part of the neem tree.
TL;DR: In this article, two new ring -C seco, bitter tetranortriterpenoid γ-hydroxybutenolides have been isolated from the fresh, green twigs of Azadirachta indica (neem) and their structures elucidated through chemical and spectral studies.
15 Dec 1986
TL;DR: The effect of leaf extracts on hatching, galling and life-cycle development in vitro of juveniles of Meloidogyne javanica (Treub.) Chitw is reported.
Abstract: Inhibition of Meloidogyne incognita juvenile hatch is reported to be caused by root-exudates of Euphorbia hirta (Yadav, 1970), Azadirachta indica (Alam e/ al., 1975) and aqueous leaf, stem and root extracts of Tagetes minuta (Toida, 1972). In a preliminary test, leaf extracts of 30 plant species were studied for their nematicidal effect on M. javanica juveniles (Nandal and Bhatti, 1983). Four weeds [Calotropis procera (Ait.) R. Br., Datura stramonium L., Ricinus communis L. and Xanthium strumarium L.] were found to be nematicidally effective and studied further. This paper reports the effect of leaf extracts on hatching, galling and life-cycle development in vitro of juveniles of Meloidogyne javanica (Treub.) Chitw,
TL;DR: A field experiment conducted at the Tamil Nadu Agricultural University, Coimbatore, India, during kharif and rabi seasons in 1984-85 with a short duration (105 days) rice cv. IR 50 showed that application of fresh neem leaf at 5 t/ha or dry NEEM leaf 1.25 t/h with urea resulted in higher N recovery per cent and N response ratio and gave increased grain yield compared to the yield obtained due to the application of urea alone as discussed by the authors.
Abstract: The farmers of tropical Asia are applying neem leaves to rice fields as green manure traditionally. Neem cake blending of urea is recommended for inhibition of nitrification and increasing nitrogen use efficiency. Field experiment conducted at the Tamil Nadu Agricultural University, Coimbatore, India, during kharif and rabi seasons in 1984–85 with a short duration (105 days) rice cv. IR 50 showed that application of fresh neem leaf at 5 t/ha or dry neem leaf 1.25 t/ha with urea resulted in higher N recovery per cent and N response ratio and gave increased grain yield compared to the yield obtained due to the application of urea alone. Besides increasing the grain yield, neem leaf application could save about 50 per cent N application and give greater net returns to the farmer.
01 Jun 1986
Journal Article•
Journal Article•
TL;DR: The structure of deacetylazadirachtinol (2) has been reassigned as 3-tigloylazadrachtol (3) on the basis of a detailed 1H and 13C n.m. spectroscopic analysis.
Abstract: The structure of deacetylazadirachtinol (2) has been reassigned as 3-tigloylazadirachtol (3)(tigloyl = 2-methylcrotonoyl) on the basis of a detailed 1H and 13C n.m.r. spectroscopic analysis.