Annals of Tropical Research 36[Supplement]:16-29(2014)© VSU, Leyte, Philippines

Correspondence : S.B. Lina Address: Department of Agronomy and Soil Science, Visayas State University, Visca, Baybay City, Leyte 6521-A Email: sblina510@yahoo.com

Growth Performance of Corn as Influenced by the Combined Application of Organic and Inorganic

Fertilizers in a Marginal Upland Soil

Suzette B. Lina, Deejay S. Maranguit, Victor B. Asio, Jessie R. Sabijon, Kier Lambert B. Demain and Ariel B. Bolledo

Department of Agronomy and Soil Science, Visayas State University, Visca, Baybay City, Leyte 6521-A

ABSTRACT

Developmentofanintegratednutrientmanagementstrategyisneededtoenhance soil quality and increase crop yields in the marginal uplands ofEasternVisayas.Duetoverypoorsoilcondition,afieldfertilizerexperimentusing the combined application of organic and inorganic fertilizers wasconducted in Inopacan, Leyte, to assess the growth performance of cornplants.Thesixtreatmentcombinationsusedinthisstudywerethefollowing:T (nofertilizeradded);T (Nationalrecommendationforcornat90-60-60kg1 2

-1 -1 -N,P O ,K Oha );T (chickendungat15tonsha );T (vermicastat15tonsha2 5 2 3 41 -1);T (1/2ofinorganic+chickendungat7.5tonsha )andT (1/2ofinorganic+5 6

-1vermicast at 7.5 tons ha ). Generally, application of organic fertilizersignificantlyincreasedsoilpH,organicmatterandtotalnitrogen.Inaddition,the treatments significantly increased, plant height, ear length, number ofgrainsperear,weightof1,000seeds,freshstoveryield,andgrainyieldofcornCorn plants in plots applied with fertilizer following T (National2

-1Recommendation for corn at 90-60-60 kg N,P O , K O ha ) and T (1/2 of2 5 2 5-1inorganic+chickendungat7.5tonsha )grewtalleranddevelopedlargerears

withmorekernelsperearandheavier1,000seedswhichresultedtohighergrainyield.However,usinginorganicfertilizeralonehadthesameeffectonearlength, number of kernels per ear of those corn plants applied withcombinationofeitherchickendungorvermicastandone-halfof inorganicfertilizers.Plants incontrolplotsandthoseamendedwithvermicastaloneshowedtheleastgrowthresponses.

Keywords:Marginaluplandsoil,degradedsoil,organicandinorganicfertilizer.

INTRODUCTION

SeveralproblemsareencounteredbythefarmersinmarginalareasofEasternVisayas.Theseproblemsincludeverylowcropproductivityduetolowinherentsoilfertility,lackofresources,inadequatesupplyofwater,lackofappropriate technologies, improperwaterandsoil conservationmanagement,highcostoffertilizer,andsoildegradation.Marginaluplandfarmersareconfrontedwithseveraldisadvantagesthatmaketheirlands“marginal”foragriculture.Toaddressthisissue,sustainablesoilnutrient-enhancingstrategiessuchastheintegratednutrientmanagement(INM)whichinvolvestheproperuseandmanagementofinorganicandorganicnutrientsourcesinproductionsystems(Janssen,1993)canbeapplied.

INMimpliesthemaintenanceoradjustmentofsoilfertilityandplantnutrient supply to an optimum level to sustain the desired cropproductivity and to minimize nutrient losses. It is achieved throughefficientmanagementofallnutrientsources.Nutrientsourcesforgrowingplantsincludesoilmineralsanddecomposingsoilorganicmatter,mineralandsyntheticfertilizers,animalmanuresandcomposts,by-productsandwastes,plantresiduesandbiologicalN-fixation(Singhetal.,2002).OneoftheprimaryobjectivesofINMistocreateandcombinebotholdandnewmethods of nutrient management into ecologically sound andeconomically viable farming systems that utilize available organic andinorganicsourcesofnutrientsinajudiciousandefficientway.

Upland areas are planted to different agricultural crops such ascassava,sweetpotato,corn,banana,coconut,uplandrice,andothercrops.Inmarginaluplands,cornissecondtoriceasthemostimportantcropwithone-thirdofFilipinofarmers,or1.8million,dependingoncornastheirmajorsourceoflivelihood.Outofthe1.6millionhectaresplantedtocorninthePhilippines,75%areinmarginaluplands.LargequantitiesofcornareconsumedinNorthandEasternLuzon,CentralandEasternVisayas,andNorthernandWesternMindanao.Cornisastaplefoodinperiodsofriceshortage,especiallyforpeoplelivinginmarginalareasandabout15%oftheFilipinoslivinginruralareasofthePhilippines.Thegritsobtainedaftermillingthegrainsareboiledasasubstituteforrice.Ofallthecerealgrains,cornishighlyvaluedduetoitsmultifarioususes,asidefromhavinghigheramountofvitamins,proteins,andcarbohydrates(PCARR,1996).

Total land area planted to cornwas highest in 1990 at 3.8millionhectares,butdeclinedat1.9%peryearfrom1985to2001(GonzalesandLapiña, 2003). The continued increase in human population

17Growth performance of corn in a highly degraded soil

ledtothedecreaseinprimeagricultural landareasforcorncultivationwhich resulted in the decline in crop production and thus corn-supplyshortage.With this problem, the primary goal of the government is toimprovesoilquality forbettercropproduction.Fertilizerapplication isconsidered the most common and conventional farm practice inaugmentingandovercomingthelimitationofinfertilesoiltosupplytheadequate nutrients for better growth and higher yields of the crops(Zamora,2007).

Fertilizersareeitherofinorganicororganicform.Theuseofinorganicfertilizersisthemostpopularandconvenientwaytoimprovesoilfertility.Inorganicfertilizersareusedinmodernagriculturetocorrectknownplantnutrientdeficiencies,providehigh levelsofnutritionand improvecropquality. However, inorganic fertilizers are generally expensive andunaffordableformanyofthefarmers(Bumb,1994;Gerneretal.,1995).Consequently, thereisaseriousnegativebalanceinnutrientbudgetsofsoils in the country posing a major constraint to sustainable soilmanagement for increasingcropgrowthandyield. Ironically, there isalargeamountoforganicwastethatcanbeturnedintofertilizersforcropproductionatlowcost.Ayineh(2011)reportedtheimportanceofusingorganic wastes that are cheap, readily available, and environmentallyfriendly. Chicken manure and vermicast are among the major organicfertilizersworthyassourceofnutrientseitheraloneor incombinationwith inorganic fertilizer. Many studies have also demonstrated thatapplicationofmanureproducescropyieldsequivalentorsuperiortothoseobtainedusingchemicalfertilizers(XieandMacKenzie,1986;Motavallietal., 1989).Leonard (1986)quoted1.1%N,1.1%P O and0.5K O for2 5 2

poultrymanureat70%moisturecontent.Moreover,vermicastisrichinmineral nutrients, vitamins, plant growth hormones, proteins andenzymes,andistherefore,consideredasaverygoodorganicfertilizerandsoil conditioner (Prabha et al., 2005). Early studies showed thatvermicompost application resulted in improved crop growth andincreasednitrogen(N)andphosphorus(P)leadingtoincreaseinyieldofcrops (Arancon et al., 2004). Other experiments demonstrated that

-1additionof5,10,and15tha vermicompostinsoilhadsignificantpositiveeffectonuptakeofelementnutrientssuchasP,K,FeandZn(Azarmietal.,2008).Azizetal.,(2010)suggestedthatintegrateduseoforganicmanurewith chemical fertilizers would be a better and practical approach tosustain soil fertility and productivity. Moreover, emerging evidenceindicates that integrated soil fertility management involving judicious

18Lina et al.

use of combinations of organic and inorganic resources is a feasibleapproachtoovercomesoilfertilityconstraints(Abedietal.,2010). Severalstudieshadbeencarriedoutonthecombinedeffectsoforganicand inorganic fertilizers on the growth and yield of maize (Mbah andOnweremadu,2009).However,inLeyteisland,onlyfewuplandfarmersare using the INM approach and there is also limited published dataavailable because the efficacy of soil amendments are said to be sitespecific.

WithagrantfromtheCommissiononHigherEducation–PhilippineHigherEducationResearchNetwork(CHED–PHERNET),aprojectonSoiland Environmental Quality Enhancement in Marginal Uplands(SEQUEMU) has been implemented to focus on the development of anintegrated nutrientmanagement strategy to enhance soil quality andincrease crop yields in the marginal uplands of Eastern Visayas. Thiscomponentstudywasconductedtoassessthegrowthperformanceofcorngrown in amarginal soil as influenced by the combined application oforganicand inorganic fertilizerand toevaluate theeffectsof combinedapplicationoforganiconsomesoilchemicalproperties.

MATERIALS AND METHOD

SiteSelection,DescriptionandLandPreparation

Selectionofthestudysitewasbasedonthecharacteristicsofmarginaluplandssuchashilly,acidic,pronetodrought,lowsoilfertilitylevelanddominatedbygrasslandvegetativecover.ThestudywasconductedinSitioBatuan,Brgy.Linao,Inopacan,Leytewhichisabout4kmeastofInopacantownwithanelevationof250masl.Thetotalareausedforthisstudywas

2620m with a clay loam soil type having low soil pH (5.0), moderateamount of soil organic matter (2.79%), and low total N (0.164%).Immediatelyaftersiteselection,theareawasplowedandharrowedtwiceatweeklyinterval.Immediatelyafterlastharrowing,furrowsweremadeatadistanceof75cmapartimmediatelyafterthelastharrowing.

ExperimentalDesignandLay-out

Thetreatmentsusedinthestudyweredesignatedasfollows:T =No1

fertilizeradded;T =NationalRecommendationrate(90–60–60N,P O ,2 2 5-1 -1 -1

K OKgha );T =ChickenDung(15tha );T =Vermicast(15tha );T =½2 3 4 5

19Growth performance of corn in a highly degraded soil

Fig.1.Photoshowstheexperimentareaafterfarmingoperation.

-1 -1RR+½ChickenDung(7.5tha );T =½RR+½Vermicast(7.5tha ).The6

experimentalareawas laid -out in randomizedcompleteblockdesign(RCBD)withsixtreatmentsandreplicatedthreetimes.Eachreplication

2wasdividedintosixplotseachplotmeasured5mx4.25m(22.25m )withsevenrows.Bothreplicationandtreatmentplotswereseparatedby1m alleyways, tofacilitatefarmoperationsandmanagementaswellasdatagathering.

FertilizerApplication,PlantingandCareManagement

Application of fertilizer was done after land preparation. Organicfertilizers(chickendungandvermicast)and inorganic fertilizers(urea,solophos, andmuriate of potash)were used as soil amendments. Theamountsoforganicfertilizerswereadjustedonair-dryweightbasis.Bothorganicandinorganicfertilizerswereappliedinfurrowsperplot. Basedonthedesignatedtreatment,cornseeds(IPBVar.6)weresowninfurrowsatadistanceof75cmbetweenrowsand50cmbetweenhillsat2to3seeds/hill.Thesameproceduresweredoneinthesecondcropping.Cornplants were thinned to 2 plants per hill one week after sowing whilereplantingofmissinghillswasdoneoneweekafterseedlingemergenceto

20Lina et al.

meet the desired plant population. Weeds were controlled by handweeding.Hilling-upwas alsodonemanually in each treatmentplot forbetterstabilityandanchorageofplants. Insectpestsanddiseaseswerecontrolled andmonitored by the PestManagement Staff of the projectusingvisualobservationmethod,sweepnet,pantrap,malaisetrapandlaboratoryanalysis.

HarvestingandDataGathering

Gatheringofdataon theagronomiccharacteristicsof theplantwasdonethroughoutthevegetativeandreproductivestageofthecornplantsduringwetanddryseasons.Theagronomiccharacteristicsandyieldandyieldcomponentsgatheredincludedthenumberofdaysfromsowingto

-1tasseling,silkingandmaturity;plantheight(cm),freshstoveryield(tha ),-1

ear length(cm);weightof1000seeds(g)andgrainyield(tha ).Whenabout90%ofthecornplantshadreachedmaturityas indicatedbythechangeincolorofthehusksandleavesfromgreentobrown,harvestinganddata gatheringof the yield andyield componentsweredone.Onlyplants in the five inner rows in each treatment plot were harvestedexcluding theborderrowsandoneendhill ineachrow.Theharvestedsampleearsweredehusked,shelled,andthegrainsweresundriedbeforeweighing.Sun-dryingofgrainswasdonefortwotothreedaystoattainthedesiredmoisturecontentofapproximately14%.Rightafterharvest,cornstoverswerecut intosmallpiecesand incorporated into thesoil in theexperimentalarea.

StatisticalAnalysis

ThedataobtainedweresubjectedtoanalysisofvarianceusingSirichaiStatisticsVersion6.00.Leastsignificantdifference(LSD)valueat5%levelofsignificancewasusedforcomparisonoftreatmentmeansbyDuncan'sMultipleRangeTest.

RESULTSANDDISCUSSION

GeneralObservation

Oneweekaftersowingtheseeds,theemergenceofcornseedlingswereobservedtobeuniforminalltreatments.Differencesinplantgrowthwere

21Growth performance of corn in a highly degraded soil

very observable one month later (Fig. 2). Plants in control plots (nofertilizeradded)wereobservedtohaveaveryinferiorgrowthcomparedtothose applied with inorganic and organic fertilizers. Generally, plantsappliedwithcombinedinorganicandorganicfertilizershadbettergrowthperformancethanthosenotappliedwithfertilizer(control)andthosewithorganic fertilizer alone. Application of organic fertilizer either appliedaloneor incombinationwith inorganic fertilizersignificantly increasedsoilpH,organicmatterandtotalnitrogen(N).

control 90-60-90kgNPK-1Chickendungalone-15Tha

-1Vermialone-15Tha Chickendung+1/2RR Vermi+1/2RR

22Lina et al.

Fig.2b.Standofcornplantsbeforeharvest.

Fig.2a.Standofcornplantsonemonthafterplanting.Notethegrowthofthecontrolplantsinthemiddle of the field and those applied with organic and inorganic fertilizers in theforeground.

AgronomicCharacteristics

Monthlyplantheight of cornunderdifferent organic and inorganicfertilizertreatmentssignificantlydiffered(Fig3).Results indicatedthatbothorganicand inorganic fertilizersaffectedplantheight significantlyfromtheearlyvegetativestageup tomaturity.Applicationof inorganic

-1fertilizerat90-60-60kgN,P O ,K Oha (T )significantlyincreasedplant2 5 2 2

height.Ontheotherhand,combinedapplicationoforganicandinorganicfertilizersusingeitherchickendungorvermicastpromotedbetterplantgrowthcomparedtothecontrolplots.Thenumberofdaysfromsowingtotaselling, silking, and maturity were also significantly affected by theapplicationoforganicandinorganicfertilizers(T ,T ,T andT )compared2 3 4 5

to the controlplots (T ) as shown inTable1. Cornplants appliedwith1

organicfertilizer,eithersinglyorincombination,ofeitherchickendungorvermicastand½oftheinorganicfertilizer,producedtasselandsilkandmatured earlier comparable to those applied with inorganic fertilizeralone.

Yieldandyieldcomponents

Theproductivityofmaizelargelydependsonitsnutrientrequirementandmanagementparticularlythatofnitrogen,phosphorus,andpotassium(Arunkumar, 2007). Table 2 shows the effect of organic and inorganicfertilizerapplicationonthenumberofkernels,weightof1000seedsand

Fig. 3. Monthly plant height (cm) of corn as influenced by application of organic and inorganic fertilizers, alone and in combination in a marginal upland soil.

23Growth performance of corn in a highly degraded soil

Treatments Number of days from sowing to

Taselling Silking Maturity

T1 – Control (without application) 54.33a 63.67a 100.00a

T2 – (90-60-60 N, P2O5, K2O kg ha-1) 46.67c 55.67c 95.00c

T3 – Chicken Dung at (15 t ha-1) 47.00c 56.67bc 96.33bc

T4 – Vermicast at (15 t ha-1) 49.33b 58.33b 99.33a

T5 – ½ RR + Chicken dung at (7.5 t ha-1) 46.00c 55.33c 95.33c

T6 – ½ RR + Vermicast at (7.5 t ha-1) 47.33bc 57.00bc 98.00ab

CV (%) 2.40 1.66 1.24

Table1.Agronomic characteristics of corn as influencedby applicationof organic andinorganicfertilizers

ear length. Fertilizer application significantly affected the number ofkernels, weight of 1000 seeds, and ear length. Plants applied with

-1inorganicfertilizer(T )andinorganicfertilizer+chickendungat7.5tha 2

(T )producedthelongestearlength(13cm)andmorenumberofkernels5

(236.43)whileplantswhichdidnot receive fertilizer (T )exhibited the1

shortesearlength,andtheleastnumberofkernels(37.33).Theweightof1000seedswasalsosignificantlyhigherwiththeapplicationofinorganic

-1fertilizer+vermicastat7.5 tha (T ). Itproduced thehighestvalueof6

238.67gbutthiswasnotsignificantlydifferentfromthoseinT ,T ,T and2 3 4

T .Plantsinthecontrolplotsshowedthelowestvalueof91.67g.Onthe5

otherhand,freshstoveryieldofcornwassignificantlyimprovedwiththeapplicationoforganicandinorganicfertilizers(Fig.4).Resultsimpliesthatapplicationof inorganic fertilizeraloneor incombinationwithorganicfertilizercouldproduceahigherstoveryieldofcorn.

Figure 5, shows the grain yield of corn as affected by fertilizerapplication.Theresultsindicatethatthegrainyieldofcornperhectarewas significantly affected by the application of organic and inorganicfertilizers. It was clearly observed that application of fertilizer, eitherinorganicororganicresultedtobetteryield.T hadthehighestgrainyield2

-1 -1(0.43tha )followedbyT (0.41tha ).T obtainedthelowestgrainyield5 1

-1(0.07tha ).However,allthesevaluesweresignificantlylowerthanthe

-1Nationalaveragecornyieldof3.5tonsha .

24Lina et al.

Means not sharing letter in common differ significantly at 0.05% probability level by Duncan's Multiple Range Test.

Treatments Ear Length (cm) No.of Kernels

per ear Weight of 1000 seeds

Stover Yield (tons ha-1)

Grain yield (tons ha-1)

T1 – Control (without application) 5.61c 41.20cd 91.67bc 0.72d 0.07b

T2 – (90-60-60 N, P2O5, K2O kg ha-1) 13.03a 236.43a 235.00a 6.86a 0.43a

T3 – Chicken Dung (15 t ha-1) 7.86bc 73.27c 220.33a 3.10c 0.36a

T4 – Vermicast (15 t ha-1) 5.75c 37.33cd 136.67ab 1.61cd 0.14b

T5 – ½ RR + Chicken dung (7.5 t ha-1) 11.48a 216.20a 226.00a 5.41b 0.41a

T6 – ½ RR + Vermicast (7.5 t ha-1) 9.24b 126.50b 238.67a 3.58bc 0.34a

CV (%) 11.67 16.29 23.51 28.39 25.51

Table 2.Yield and yield components of corn as influenced by the application of organic and inorganic fertilizers in a marginal upland soil.

Means not sharing letter in common differ significantly at 0.05% probability level by Duncan's Multiple Range Test.No significant difference 0.07 b and 0.14 b, 0.43a, 0.36a and 0.41a, 0.34a no significant difference.

25

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-1Figure 4. Fresh stover yield (t ha ) of corn as influenced by application of organic and inorganic fertilizers in a marginal upland soil

-1Figure5.Grainyield(tha )ofcornatharvestasinfluencedbyapplicationoforganicandinorganicfertilizersinamarginaluplandsoil

26Linaetal.

Thefindingsof thepresentstudyagreewiththatofMakindeetal.,(2001a)whoreportedthatthesoleapplicationofinorganicfertilizerormixture of organic and inorganic fertilizer significantly increased cornyieldinmarginalareas.Inasimilarstudy,Zhaoetal.(2009)foundthatapplication of farmyard manure combined with chemical fertilizermanagementresulted tohigher increase inmaizeyieldcomparedwiththoseunderunfertilizedtreatment.Kimetoetal.(2004)alsofoundthatacombinationofbothorganicandinorganicnutrientsourcesgavehighermaizeyieldthanorganicfertilizeralone.

CONCLUSION

Results of the study revealed that application of organic fertilizersignificantlyincreasedsoilpH,organicmatter,andtotalnitrogen.Amongtheagronomicparametersgathered,plantheight,earlength,numberofgrainsperear,weightof1,000seeds,freshstoveryield,andgrainyieldofcorngrownindegradedsoilweresignificantlyincreasedbytheapplicationoforganicandinorganicfertilizers.Moreover,cornplantsinplotsappliedwithfertilizerfollowingT (NationalRecommendationforcornat90-60-2

-160kgN,P O ,K Oha )grewtalleranddevelopedlargerearswithmore2 5 2

kernelsperearandheavier1,000seedswhichresulted inhighergrainyield.However,usinginorganicfertilizeralonehadthesameeffectonearlength and number of kernels per ear of corn plants applied withcombinationofeitherchickendungorvermicastandone-halfofinorganicfertilizers.Ontheotherhand,plantsincontrolplotsandthoseamendedwithvermicastaloneshowedtheleastgrowthresponses.

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29Growth performance of corn in a highly degraded soil