Effect of Potassium Levels on Processing Varieties of Potato (Solanum Tuberosum L.)

Abstract

Potato IS fou_rth Important food crop after rice, wheat and maize in India, with an area of 1.78 m ha, produ~t10n ~f31.1 m_tones and productivity of 17.6 t ha·•. The crop has witnessed 7.7~ 19.4 & 2.5 times mcrease m area, production and productivity, respectively, during the penod 1 ~49-50 to 2008-200~. Consequently, India has emerged as the third largest potato producer m the world after Chma and Russia. The state of Uttar Pradesh with 28. 1 % area, 33.4 % pr~duction and producti~ity of21.4 t ha-1 , occupy prominent position. Attributed to improper selection of genotypes and Imbalanced use of plant nutrients, India's productivity is much lower than the l'fetherlands (45.7t ha"\ Belgium (45.6t ha"\ and U.S. A. (45.2t ha-1). With increasing trends in demand for potato products (chips, French fries etc) and recurring gluts, processing has emerged a viable option to ensure remunerative prices to the farmers. The investigation was therefore, conducted on sandy loam soil, low in organic C and N, medium in available P and K with neutral pH at Meerut located in semi-arid sub-tropical region, during rabi 2010-11. Treatments comprising of three genotypes (K. Himsona, K. Frysona and K. Chipsona-3) and four potassium levels (0, 75, 150 and 225 kg K20 ha·•> were tested in R.B.D. with 03 replications. The crop enjoyed 0.94 mm of rains and temperature extremes of 3.0- 30.80C during the crop period (Nov. 07, 2010 to March 07, 2011). Results revealed that K. Chipsona-3 gave highest yield of process grade tubers (21.8 t ha-1 ) followed by K. Himsona (9.9 t ha-1 ) and K. Frysona (6.5 t ha-1 ) with respective contribution of73.2, 40.1 and 33.7% to total tuber yield and 86, 85& 83% of total dry matter in tubers. Superiority ofK. Chipsona-3 was attributed to better canopy development and high efficiency in intercepting PAR indicated by highest LAI (1.7), PARI (70.2%) and lowest PAR below canopy (196.8 J.1 mols m-2 S"1 ) and Tau value (0.29). Respective values were 1.4, 61.9%, 246.0 J.1 mols m·2 s-I and 0.38 forK. Himsona and 1.0, 320.9 J.1 mols m-2 s-1 , 52.3% and 0.47 forK. Frysona. Among, Dry matter, crude protein, glucose and fry color score, the differences were suignificant only in respect of dry matter being highest (19.2%) in K. chipsona -3. The crop removed nitrogen in largest amounts followed by potassium and phosphorus. K. Chipsona 3 removed highest amount of N & K while Kufri Frysona accumulated highest amount of P. K. Chipsona-3 fetched highest gross return ( Rs.1,79,57 ha"1 ) and Net return (Rs.98,472 ha"1 ) with benefit cost: ratio of 2.22 followed by K. Himsona (Rs. 1,48,654 ha"1 , 68,069 ha-1 and 1.84) and K. Frysona (Rs 1,35,482 ha-1 , 54,897 ha-1 and 1.68). Residual effect on soil fertility was non-significant. Crops fertilized with 150 and 225 kg K20 ha"1 remaining at par with that receiving 75 kg K20 ha"1 recorded significantly higher number and yield of process grade tubers than with no K. The contribution of process size tubers towards total tuber yield was 49.8, 50.8, 52.0&53.8% with 0, 75, 150 & and 225 kg K20 ha"1 , respectively. Potassium application had favorable effect on quality including chips acceptability. Soil organic carbon (0.41-0.43%), available N (195.3- 195.9 kg ha"1) and available P (20.1-21.1 kg ha"1 ) remained statistically unaffected. However, available K increased significantly from177.1 (no K) to 196.1 kg ha· with 225 kg K20 ha-1 Crop given 150 kg K20 ha"1 fetched Rs. 32,532, 18,274 and 2,883 ha-1 rupees more than those given 0, 75 and 225 kg K20 ha·t, respectively with highest benefit cost: ratio (2.07). The genotypes differed significantly in their growth, ~eld and_ quality, and potassium application also had a favorable effect on their performance, Irrespective of the genotypes. K. Chipsona-3 proved the best option in Western U.P. conditions followed by K. Frysona and K. lfunsona, p~11r!y under delayed sowing. There is a need to 11pply 150 kg ~0 ha·