Effect of Organic Sources of Nutrients on Growth and Yield of Turmeric ( Curcuma longa L.)

A field experiment was conducted at Agricultural

Turmeric (Curcuma longa L.) is a perennial rhizomatous herb and regarded as an important spice of Asian cuisine. Turmeric demands more mineral nutrients and it generally responds to increased soil fertility and quantity of fertilizers applied (organic and inorganic) (Selvarajan and Chezhiyan, 2001). The recent energy crisis and the hike in the prices of the inorganic fertilizers necessitate the integrated use of organic source of nutrients with fertilizers. Wellgro organic manure is a unique form, a blend of neem and non-timber forest produce, free from harmful chemicals and a rich source of nutrients. This organic based farm input addresses soil fertility and crop nutrition in line with the concept of integrated nutrient management. With these ideas, this experiment was carried out to find out the effect of organic sources of nutrients on growth parameters, yield attributes and rhizome yield of turmeric.

Materials and methods
A field experiment was conducted during June 2010 -March 2011 at Agricultural Research Station, Bhavanisagar, Tamil Nadu. The soil of the experimental field was red sandy loam in texture having slightly acidic pH (6.27) with medium soluble salts (0.75 dSm -1 ), medium in organic carbon content (0.5 per cent), low in available N (205 kg ha -1 ), medium in available P(15.7 kg ha -1 ) and high in available K (376 kg ha -1 ). Recommended dose of N, P and K was applied at 150 kg, 60 kg and 100 kg ha -1 . The entire phosphorus was applied as basal and N, K and wellgro formulations were applied in six equal splits at 0, 30, 60, 90, 120 and 150 DAP. Planting was done with a spacing of 45 x 15 cm. Farm yard manure was applied at 12.5 t/ha for treatment T14 (100 % RDF + FYM) and T15 (75 % RDF + FYM). Quantity of wellgro formulations required for experiment was worked out and given in Table 1. Nutrient content of wellgro products and farm yard manure were furnished in Table 2.

Results and Discussion
The growth characters of turmeric viz., days for rhizome sprouting, leaf area index, and dry matter production were significantly influenced by application of wellgro organic manures. Application of 100 % RDF along with 40 % wellgro soil recorded significantly lesser number of days for rhizome sprouting. Application of 100 % RDF + 40 % wellgro soil registered significantly higher LAI at 180 DAP and found on par with 75% RDF + 40 % wellgro pellets. Application of recommended dose of fertilizers along with 40 % wellgro soil recorded higher dry matter accumulation at 180 DAP. This was due to higher underground rhizome mass. The higher uptake of nutrients could have led to maximum dry matter accumulation. The results of the present *Corresponding author email: shanthi_agri@yahoo.co.in investigation is in conformity with findings of Sadanandan and Hamza (1998) in ginger. Yield attributes viz., girth (cm), weight (g) and fresh weight (g) of rhizome were positively 321 influenced by the application of wellgro formulations ( Table 3). Application of 100 % RDF + 40 % wellgro soil recorded wider and heavier mother and primary rhizome at harvest stage. Increase in girth and weight of rhizome was due to slow release of nutrients from wellgro soil resulting in greater uptake of nutrients. This is in concurrence with earlier findings of Rana and Rattan (1994). More fresh weight of rhizome was registered with application of 100 % RDF + 40 % wellgro soil.
Application of 100 % RDF along with 40 % wellgro soil recorded higher rhizome yield (26076 kg ha -1 ). Lower yield was recorded with 100 % RDF application. Increase in rhizome yield was 51.1 % over 100 % RDF. The supremacy of wellgro soil was due to greater movement and availability of phosphorus and micronutrients to plants. This could have favoured the increase in yield of rhizomes. The results of the present study is in corroboration with Thanuja (2002) in black pepper.

Conclusion
The results of the present study indicated that application of 100 % RDF along with 40 % wellgro soil (organic manure from ITC, Guntur)higher growth and yield attributes and a rhizome yield of turmeric. Cost of wellgro soil, pellets and grains -Rs. 6 / kg