RESPONSE OF SOIL NUTRIENT STATUS ON LEAF NUTRIENT CONTENT AND FRUIT YIELD OF 'KINNOW' MANDARIN UNDER DRIP IRRIGATION SYSTEM

The present study entitled “Response of soil nutrient status on leaf nutrient content and fruit yield of ‘Kinnow’” was conducted at different locations of seven ‘Kinnow’ orchards at SriGanganagar district of Rajasthan state of India under drip irrigation system at the orchards of private fruit growers during 2005-06. The study included analysis of soil profile with respect to physical and chemical characteristics, determination of important essential plant nutrients, and analysis of ‘Kinnow’ fruits at fruiting time. The soil pH and calcium carbonate content were found high whereas, organic carbon, available nitrogen, available iron, available zinc were found low. The available phosphorus, available potassium, available copper and available manganese found low to medium. Analysis of leaf samples showed that phosphorus, potassium, calcium, iron, magnesium, copper was found to be sufficient in majority of samples whereas nitrogen, zinc and manganese content were found low. The content of nitrogen, phosphorus, potassium, calcium and magnesium in leaves ranged from 2.25 to 2.59%, 0.13 to 0.34%, 0.31 to 0.54%, 1.35 to 1.94% and 0.25 to 0.36%, respectively whereas iron, zinc, copper and manganese lied between 17.30 to 23.60 ppm, 22.92 to 38.65 ppm, 2.80 to 4.50 ppm and 29.77 to 39.40, respectively.
The correlation between leaf nitrogen, phosphorus, potassium, iron, zinc and copper were positive and significantly correlated with available nitrogen, available phosphorus, available potassium, available iron, available zinc and available copper contents of soils. The average fruit weight, T.S.S., acidity, ascorbic acid, juice content and fruit yield varied between 108.96 to 151.39 g, 10.40 to 11.60 °B, 0.98 to 1.02%, 32.93 to 36.02 mg/100 g pulp, 51.80 to 55.70 ml and 47.53 to 71.33 kg tree^-1, respectively. The fruit weight and fruit yield were significantly and positively correlated with nitrogen, phosphorus, potassium, iron, zinc and copper contents of leaf.