Effect of Chemically Treated Wood Coal on the Physiochemical Properties of Tomato (Riogrande)

Abstract

In a pot experiment, wood coal was applied to tomato plants of Rio Grande cultivar in the form of 32 different treatments, which were made by treating the same number of powdered wood coal portions (250g each ) with one liter each of 32 different acid base solutions i.e. 4% HCl, 4% H2SO4, 15% HNO3, 5% NaOH, 5% KOH abbreviated as 'C', 'F','N', 'S', 'P' and their combinations CF, CN, CS, CP, FN, FS, FP, NS, NP, SP, CFN, CFS, CFP, FNS, FNP, FSP, CNS, CNP, CSP, FSP, NSP, CFNS, CFNP, CFSP, CNSP, FNSP, CFNSP in one ratio one respectively. Quality of the treated wood coal and its role as fertilizer was studied in term of physicochemical parameters of pots soil and tomato plants in comparison to controls i.e. NPK, humic acid, F.Y.M, wood coal and untreated soil. pH and EC of the treated wood coal showed significant difference (P<0.05) with ranges of 1.48 to 11.9 and 3.45 to 28.4µs/dl respectively, where most of pH values were in acidic region, except S, P, CS, FP, SP, CSP and FSP treatments while EC was highest in acidic or acid containing treatments. Soil parameters showed significant variation (P<0.05) where the least EC 96.60 µS/dl was found in untreated soil while highest 190.10 µS/dl in NSP treated soil. Acidity of soil ranged from 0.97x10-2g/100mL in S to 1.41x10-2g/100mL in FP treated soils. The highest value 6.58x10-3% of inorganic nitrogen was observed in CFNSP treated soil. An increase in soil pH from 7.85 to 8.61 was observed after treatments where treatment wise comparison showed a range from 8.10 to 8.32 in CFP and CNS respectively. The effect of treatments on soil minerals in mg/kg indicated greatest variation in Fe from 2.759 to 5.358, Mn from 0.324 to 0.73, Na from 3.9 to 11.9 and K from 8.60 to 15.30 while other minerals like Cu, Zn, P, Pb and Ni showed moderate variability. Higher trend of soil minerals were found in sulfuric or nitric acids containing treatments. Data of tomato plants physical parameters, taken in intervals each of 15 days, varied significantly (P<0.05) where higher values of plant height 51.53cm was found in CN, leaf area 26.77 cm2 in FSP, No. of leaves plant-113.13 in CFN, No. of leaflets plant-1 53.93 in NP and No. of flower plant-1week-1 13.80 in SP treated plants with lower values of these parameters 25.20 cm, 15.94cm2, 8.07, 33.87 and 1.42 in untreated soil respectively, while No. of branches 4.56 of CNP were higher than humic acid 1.56 and No. of fruits plant-1week-1 4.75 of FNS than 1.00 of CSP. Proximate composition of plant parts taken in percent showed the higher values of moisture 96.28, crude protein 1.30 and NFE 88.36 in roots, ash 4.75 and crude fiber 7.32 in stem and crude fat 2.64 in young leaves. Percent proximate composition of treated plants varied from 0.5 to 3, where maximum values of moisture 95.67, ash 4.03, crude fat 2.05, crude protein 1.21, crude fiber 6.05 and NFE 87.94 were detected in C, CFP CNS, CNSP, CFNP and FN treated plants respectively. Except Na and K with highest values of 16.10 and 37.63, other minerals of plant parts, like Fe, Zn, Mn, P etc., varied from 0.01 to 3.00mgKg-1 where most of them were higher in roots and leaves of tomato. Treatment variation of these mineral were also significant at P=0.05 where highest values of Fe was found in CNSP, Zn, Cu and in C, Mn in FNSP, Na and P in NSP, K in N and Ni was highest in FSP treated plants. Most of the fruits proximate parameters except moisture 94.82% and NFE 96.88% ranged from 0.02 to 3% with higher values in KOH containing treatments. The lowest values of these minerals were present in untreated soils. Among the mineral content of fruits Fe content of FNSP, Zn of CFSP, Cu and Na of CFNS, Mn and P of CS, Pb of CNP, Ni of SP were highest compared to other treatments. Highest values of Carbon 84.16% and lycophene 4.50mgKg-1 were found in CFP and FSP treatments, while chlorophyll was high at day 45of transplantation and in CFNSP treated plant. From the results it was conjectured that treated wood coal may be developed as fertilizer for tomato and other crops where further research particularly under field condition are needed.