Dr.P.N.Siva Prasad
@angrau.ac.in
Subject Matter Specialist Crop Production & Soil Science
Dr.K.L.Rao KVK, Garikapadu NTR district, A.P
EDUCATION
Doctor of Philosophy in Soil Science
RESEARCH, TEACHING, or OTHER INTERESTS
Agricultural and Biological Sciences, Agronomy and Crop Science, Soil Science
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
PN Siva Prasad and CT Subbarayappa
Bangladesh Journals Online (JOL)
Pot experiment was conducted at University of Agricultural Sciences, Bangalore, Karnataka, which received five treatments i.e., 0, 5, 10, 15, 20 kg ZnSO4/ha. Among all the treatments Recommended NPK + ZnSO4 @ 20 kg/ha recorded highest mean dry matter yields of tomato. The amount of zinc extracted by different extractants were in the following order as Mehlich-3 - Zn > 0.1 N HCl - Zn > AB-DTPA - Zn > 0.01 N EDTA - Zn > DTPA - Zn > 0.01 M EDTA + 1 N NH4OAc - Zn > 1 N NH4OAc (pH 4.6) - Zn > 1 N NH4OAc (pH 7) - Zn. Among the various extractants tried DTPA - Zn gave positive and higher significant correlation with Brays per cent Yield (r = 0.781). The next better extractants were Mehlich-3 (r = 0.726) and AB-DTPA (r = 0.576) which were also significantly positively correlated with Brays per cent yield. The critical limits of DTPA, Mehlich-3, AB-DTPA, tomato plant and tomato fruit by graphical method were 1.12, 2.15, 1.20, 34 and 58 mg/kg, respectively. Bangladesh J. Bot. 51(4): 655-662, 2022 (December)
Pothagani N. Siva Prasad, Chickadibburahalli Thimmappa Subbarayappa, Ayyappa Sathish, and Venkataramanappa Ramamurthy
Informa UK Limited
Abstract Critical limit (CL) determination of zinc (Zn) is much more important to assess the response of crop to its application in soils and for crops actual fertilizer requirement. This experiment was conducted at University of Agricultural Sciences, Bangalore in sandy clay loam texture soils. Based on the results of the pot culture experiment, the critical limits of DTPA, AB-DTPA, Mehlich-3, tomato plant and tomato fruit are 1.12, 1.20, 2.15, 34 and 58 mg kg−1, respectively. Tomato was highly responded to Zn application in soils below the critical limit whereas soils with Zn greater than 1.12 mg kg−1 did not respond much. For the confirmation of pot culture results, two field experiments were carried out during 2017–18 with different Zn treatments one in high and other in low zinc soils. The study concluded that for both low zinc and high zinc soils external application of zinc through Recommended dose of fertilizers (RDF) + ZnSO4 @ 30 kg ha−1 as soil application (SA) + foliar application (FA) @ 0.50% ZnSO4 and RDF + ZnSO4 @ 20 kg ha−1 as SA + FA @ 0.25% ZnSO4 significantly improved yield, nutrient concentration and uptake of nutrients, which helped in getting higher benefit cost (B:C) ratio of 4.74 and 4.96, respectively. This information is helpful in site-specific zinc nutrition in tomato and to enhance the productivity and profitability.