Effect of moisture regimes and pesticides of different biodegradability on transformation
Dataȱ inȱ Tableȱ 6ȱ revealedȱ thatȱ bothȱ theȱ dosesȱ ofȱ Additionȱofȱpesticidesȱhasȱlittleȱeffectȱonȱhexosamineȱ
endosulfanȱhasȱnoȱdrasticȱeffectȱinȱaccumulationȱofȱ Nȱinȱsoilȱ(Figureȱ1ȱtoȱ4).ȱHowever,ȱpesticideȱtreatmentȱ
hexosamineȱNȱinȱsoilȱtreatedȱwithȱorȱwithoutȱinorganicȱ influencedȱ theȱ accumulationȱ ofȱ hydrolysableȱ NH 4 +
N.ȱ However,ȱ atȱ theȱ lowerȱ doseȱ ofȱ Chloropyriphosȱ andȱ aminoȱ acidȱ Nȱ inȱ soils.ȱ Additionȱ ofȱ pesticidesȱ
treated,ȱcomparativelyȱlowerȱamountȱofȱhexosamineȱ eitherȱendosulfanȱorȱchloropyriphosȱatȱlowerȱdose,ȱ
–ȱNȱwasȱrecordedȱatȱtheȱendȱofȱincubationȱperiodȱinȱ inȱ general,ȱ decreasedȱ theȱ hydrolysableȱ NH 4 + butȱ
theȱsoilsȱtreatedȱwithȱinorganicȱN.ȱTheȱdecreaseȱwasȱ onȱtheȱotherȱhand,ȱincreasedȱaminoȱacidȱNȱinȱsoil.ȱ
moreȱpronouncedȱinȱwaterloggedȱsituationȱthanȱtheȱ Therefore,ȱitȱisȱclearȱthatȱpesticidesȱhaveȱanȱimpactȱ
soilsȱmaintainedȱunderȱ60%ȱMHC.ȱSoilsȱtreatedȱwithȱ onȱmineralizationȱandȱimmobilizationȱofȱorganicȱandȱ
higherȱdoseȱofȱchloropyriphosȱshowedȱanȱincreasingȱ inorganicȱNȱinȱsoil.
trendȱofȱaccumulationȱofȱhexosamineȱ–ȱNȱthroughoutȱ
theȱ periodȱ ofȱ incubation.ȱ Theȱ recordedȱ higherȱ Conclusion
amountȱofȱhexosamineȱ–ȱNȱinȱuntreatedȱsoilsȱatȱtheȱ
Additionȱofȱpesticidesȱofȱdifferentȱbiodegradabilityȱ
endȱofȱincubationȱperiodȱisȱdueȱtoȱimmobilizationȱofȱ
hindersȱ theȱ ammonifyingȱ processȱ butȱ onȱ theȱ
inorganicȱformsȱofȱNȱinȱsoils.ȱThisȱtrendȱofȱresultsȱ
otherȱ hand,ȱ encouragesȱ nitrification.ȱ Higherȱ doseȱ
isȱobservedȱforȱtheȱsoilsȱmaintainedȱunderȱbothȱtheȱ
ofȱ endosulfanȱ favoursȱ nitrificationȱ evenȱ underȱ
moistureȱlevels.
waterloggedȱ situation.ȱ Additionȱ ofȱ Endosulfanȱ
Perusalȱ ofȱ theȱ resultsȱ inȱ Tableȱ 7ȱ revealedȱ thatȱ andȱChloropyriphosȱincreasedȱtheȱaccumulationȱofȱ
irrespectiveȱ ofȱ moistureȱ regimesȱ andȱ pesticidesȱ availableȱ Nȱ inȱ soilȱ particularlyȱ underȱ waterloggedȱ
addition,ȱ comparativelyȱ higherȱ amountȱ ofȱ aminoȱ situation.ȱ Differentȱ formsȱ ofȱ organicȱ Nȱ areȱ inter-
acid-NȱisȱaccumulatedȱinȱN-treatedȱoverȱtheȱuntreatedȱ convertibleȱwithinȱthemselves.
systemȱparticularlyȱatȱtheȱlaterȱstageȱofȱinvestigation.ȱ
Again,ȱirrespectiveȱofȱN-fertilization,ȱatȱhigherȱdoseȱ
References
ofȱpesticides,ȱaȱfavourableȱenvironmentȱwasȱcreatedȱ PrabhuȱAMȱandȱRautȱSVȱ2011.ȱIsolationȱandȱCharacterizationȱ
toȱregisterȱaȱcomparativelyȱhigherȱamountȱofȱaminoȱ
ofȱ Pesticideȱ Resistantȱ Strainsȱ ofȱ Azotobacterȱ spp.,ȱ
Azospirullumȱ spp.,ȱ Rhizobiumȱ spp.ȱ andȱ Phosphateȱ
acid-Nȱ inȱ waterloggedȱ overȱ theȱ soilȱ maintainedȱ atȱ
Solubilizingȱ Microorganismsȱ andȱ theirȱ Applicationȱ asȱ
60%ȱofȱtheȱMHC.ȱSimilarȱfindingsȱwereȱalsoȱreportedȱ
Biofertilizers.ȱ Trends in Biosciece 4 (2):ȱ194-197.
earlierȱbyȱMukhopadhyayȱ et al. (1985).ȱTheȱincreaseȱ
Aulakhȱ MS,ȱ Kheraȱ TS,ȱ Doranȱ JW,ȱ Bronsonȱ KFȱ (2001b)ȱ
inȱ aminoȱ acid-Nȱ withȱ concomitantȱ decreaseȱ inȱ
Denitrification,ȱN 2 OȱandȱCO 2 ȱfluxesȱinȱrice-wheatȱcroppingȱ
hydrolysableȱ organicȱ NH 4 + -Nȱ underȱ waterloggedȱ
systemȱasȱaffectedȱbyȱcropȱresidues,ȱfertilizerȱNȱandȱlegumeȱ
situationȱ leadsȱ toȱ concludeȱ thatȱ differentȱ fractionsȱ
greenȱmanure.ȱ Biology and Fertility of Soils 34 :ȱ375-389.
ofȱorganicȱNȱareȱinter-convertibleȱwithinȱthemselvesȱ Aulakhȱ MS,ȱ Kheraȱ TS,ȱ Doranȱ JW,ȱ Bronsonȱ KFȱ (2001a)ȱ
Managingȱ cropȱ residueȱ withȱ greenȱ manure,ȱ ureaȱ andȱ
dependingȱ uponȱ theȱ microenvironmentȱ ofȱ theȱ
tillageȱinȱaȱrice-wheatȱrotation.ȱ Journal of Soil Science Society
rhizosphereȱsoil (Sahaȱ1999).
of America 65 :ȱ820-827.
Toȱgetȱaȱclearȱpictureȱofȱtheȱeffectȱofȱpesticidesȱonȱ Aulakhȱ MS,ȱ Kheraȱ TS,ȱ Doranȱ JW,ȱ Singhȱ K,ȱ Singhȱ Bȱ 2000.ȱ
changesȱinȱdifferentȱformsȱofȱNȱinȱsoilȱmaintainedȱ
Yieldsȱ andȱ nitrogenȱ dynamicsȱ inȱ aȱ rice-wheatȱ systemȱ
usingȱgreenȱmanureȱandȱinorganicȱfertilizer.ȱ Journal of Soil
underȱtwoȱdifferentȱmoistureȱregimesȱinȱpresenceȱandȱ
Science Society of America 64 :ȱ1867-1876.
absenceȱofȱaddedȱinorganicȱN,ȱtheȱmeanȱvalueȱofȱtheȱ
BalangerȱG,ȱWinchȱJE,ȱTownshandȱJLȱ1985.ȱCarbofuranȱeffectsȱ
dataȱatȱdifferentȱstagesȱareȱgraphicallyȱpresentedȱinȱ
onȱestablishmentȱofȱlegumesȱinȱrelationȱtoȱplantȱgrowth,ȱ
Figureȱ1ȱtoȱ4.ȱIrrespectiveȱofȱpesticidalȱtreatments,ȱinȱ
nitrogenȱfixationȱandȱsoilȱnematodes.ȱ Canadian Journal of
general,ȱhighȱamountȱofȱavailableȱNȱisȱaccumulatedȱinȱ
Plant Science 65 :ȱ423-433.
waterloggedȱthanȱtheȱsoilȱmaintainedȱatȱ60%ȱofȱNHCȱ BradyȱNC,ȱWeilȱRRȱ2007.ȱNitrogenȱandȱSulphur.ȱIn:ȱNatureȱ
(Figureȱ1ȱandȱ2).ȱNȱadditionȱleadsȱtoȱaccumulationȱofȱ
andȱ Propertiesȱ ofȱ Soils.ȱ 13thȱ Edition.ȱ Prenticeȱ Hallȱ
PublisherȱCompany,ȱUSA.
higherȱamountȱofȱavailableȱNȱinȱsoilȱ(Figureȱ3ȱandȱ4).ȱ
377