Integrated Management of Nitrogen and Sulfur Sources in Combination with Amino acids Amelioration for Onion Plants Production under Alluvial Soil Condition

Abstract

Two field experiments were carried out as split-split plot design at Experimental Farm of Tag El-Ezz, Agricultural Research Station (30 o 59 \ N latitude, 31 o 58 \ E longitude´), Dakahlia Governorate, Egypt, during winter seasons of 2018-19 and 2019-20 to study the integration managements of N and S fertilizers as three nitrogen sources in main plots as (urea(Ur), ammonium nitrate(AN) and ammonium sulfate(AS)), two elemental sulfur(ES) treatments (without and with sulfur as a soil application) in sub plots as well as in addition to three amino acids(AA) treatments (control, L-methionine and L-cysteine) as foliar application in the sub-sub plots on growth, yield and its components of onion plants (Allium cepa L.) cv.Giza Red(GR) were studied. Available elements N,P,K and S in the experimental soil were determined before cultivation and after harvesting. The obtained results could be summarized as follow: AN fertilizer give the highest effective vegetative growth values, quality parameters, yield and its components compared to other nitrogen sources. Soil application of ES has a significant effect on all studied parameters, while L-methionine is more effective than L-cysteine. Interaction of AN and foliar application of methionine in integration with ES application achieve the highest values of vegetative growth criteria, quality parameters, yield and its components of the onion plants. Highest residual NPK concentration in the soil were recorded with the interaction of AS and without ES and AA application, while the highest values of residual S are obtained by the interaction of AS and methionine foliar application in presence of ES application.