Impact of azadirachtin, an insecticidal allelochemical from neem on soil microflora, enzyme and respiratory activities

The effect of 10% azadirachtin granules (alcoholic extract of neem seed kernel mixed with China clay) was studied on the population of bacteria, actinomycetes, fungi, Azotobacter and nitrifying bacteria; soil dehydrogenase, phosphatase and respiratory activities on 0, 15th, 30th, 60th and 90th days...

Full description

Saved in:
Bibliographic Details
Published in:Bioresource technology 2007-11, Vol.98 (16), p.3154-3158
Main Authors: Gopal, Murali, Gupta, Alka, Arunachalam, V., Magu, S.P.
Format: Article
Language:English
Subjects:
allelochemicals
Azadirachta - chemistry
Azadirachta indica
Azadirachtin
Azotobacter
Bacteria - drug effects
Bacteria - enzymology
Bacterial Proteins - metabolism
Biological and medical sciences
Enzymes
Fundamental and applied biological sciences. Psychology
Fungal Proteins - metabolism
Fungi - drug effects
Fungi - enzymology
Insecticides - pharmacology
Limonins - pharmacology
Microflora
Neem
Oxidoreductases - metabolism
Phosphoric Monoester Hydrolases - metabolism
Soil
Soil Microbiology
soil microorganisms
Soil Pollutants - pharmacology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The effect of 10% azadirachtin granules (alcoholic extract of neem seed kernel mixed with China clay) was studied on the population of bacteria, actinomycetes, fungi, Azotobacter and nitrifying bacteria; soil dehydrogenase, phosphatase and respiratory activities on 0, 15th, 30th, 60th and 90th days after application in sandy loam soil collected from the fields. It was observed that baring the Azotobacter sp., azadirachtin at all the doses exerted a suppressive effect on the rest of the microbial communities and enzyme activities in the initial 15 day period. The population of bacteria, actinomycetes besides phosphatase and respiratory activities recovered after 60th day and subsequently increased significantly. The fungi and nitrifiers were most sensitive groups as their numbers were reduced significantly throughout the studies. The two times and five times recommended dose of azadirachtin had very high biocidal effects on the soil microorganisms and its activities. However, analysis of the data by the Shannon Weaver index showed that azadirachtin reduces both the form and functional microbial diversity at all doses.
ISSN:0960-8524
1873-2976
DOI:10.1016/j.biortech.2006.10.010