Location: Southern Insect Management ResearchTitle: Effect of potassium application rate on cotton growth and yield under irrigated and dryland conditions
|DENTON, SAVANA - Mississippi State University|
|DODDS, DARIN - Mississippi State University|
|KURTS, JASON - Mississippi State University|
|GORE, JEFF - Mississippi State University|
|RAPER, TYSON - Mississippi State University|
|COX, MICHAEL - Mississippi State University|
|DHILLON, JAGMAN - Mississippi State University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/19/2022
Publication Date: 1/25/2023
Citation: Denton, S., Dodds, D., Kurts, J., Gore, J., Raper, T., Cox, M., Dhillon, J. 2023. Effect of potassium application rate on cotton growth and yield under irrigated and dryland conditions. Agronomy Journal. 115 (1): 395-407. https://doi.org/10.1002/agj2.21245.
Interpretive Summary: Cotton grown on soils tested to contain adequate potassium (K) levels was investigated for K deficiency in a series of field experiments. Applications of K in preseason and during the season in irrigated and non-irrigated fields in two different soil types were compared against the controls. Data on lint yield and fiber quality, leaf K concentrations, and cotton growth and development parameters were collected. In Leeper silty clay loam (LSCL) soils lint yields increase was significant compared to Marietta fine sandy loam (MFSL) under rainfed and irrigated conditions. Leaf K concentrations at first bloom and 4 weeks after first bloom responded showed significant increase. This investigation showed that foliar K application alone are insufficient, and responses to granular K and irrigation were dependent on soil mapping units.
Technical Abstract: Potassium (K) deficiency in cotton (Gossypium hirsutum L.) grown on soils with adequate soil test K levels has become more prevalent. Field experiments were conducted with or without irrigation as the main plot and K fertilizer rates as subplot treatments. Granular K was applied preseason at rates of 0, 45, 90, 134, 179, and 224 kg K ha-1. Two in-season foliarKprogramsappliedatotalofeither2.8or 5.6kgKha-1wereincludedtocompareagainstthecheck.Experimentswereset upontwodistinctsoilmappingunits(SMUs)inStarkville,MS,includingaLeeper siltyclayloam(LSCL;fine,smectitic,nonacid,thermicVerticEpiaquepts)anda Mariettafinesandyloam(MFSL;fine-loamy,siliceous,active,thermicFluvaquenticEutrudepts).Responsevariablescollectedincludelintyieldandfiberquality,leaf Kconcentrations,andcottongrowthanddevelopmentparameters.Acrossallyears oftheexperiment,LSCLlintyieldsincreasedatarateof41and118kgha-1per 45kgKha-1underrainfedandirrigatedconditions,respectively.OntheMFSL, lintyieldincreasewasnotsignificantforeitherrainfedorirrigatedconditions.Leaf Kconcentrationsatfirstbloomand4weeksafterfirstbloomrespondedquadraticallytoKrate,withpeakleafKconcentrationsoccurringbetween134and179kgK ha-1.Differencesincottongrowthparameterswereobserved;however,differences werelikelyphysiologicallyinsignificant.Forallparameters,foliarKapplicationprogramsdidnotdifferfromtheuntreatedcheck.Thisinvestigationshowedthatfoliar Kapplicationaloneareinsufficient,andresponsestogranularKandirrigationwere dependentonSMUs.