Response of growth, yield and quality of small onion (Allium cepa L. var. aggregatum don.) to Tamil Nadu Agricultural University-Water Soluble Fertilizers (TNAU-WSF)

Abstract

Enhancing the food production for the growing world population has needed application of highly sustainable and efficient inputs to produce more food per unit of land. Hence, Tamil Nadu Agricultural University (TNAU), Coimbatore, Tamil Nadu has produced Water soluble fertilizers (WSF) in its maiden attempt and it is necessary to optimize on different crops. Small onion is one of the most important vegetables in the Indian diet and it has high demand but low productivity. To enhance crop productivity and quality of small onions, the application of TNAU-WSF was taken up. A field experiment was laid out in a Randomized block design (RBD) incorporating 8 treatments comprising of application of RDF at100% NPK as TNAU WSF, soil test based application of 75%, 100%, 125% NPK ha-1 as TNAU-WSF with soil application of sulphur (S) and foliar spray of TNAU Liquid multi micronutrient (LMM) and without S and TNAU LMM and absolute control. Each treatment was replicated thrice with onion (CO 4). Soil test based application of 125% NPK ha-1 as TNAU-WSF with sulphur (S) and TNAU LMM recorded significantly higher in plant height (54.01 cm), the number of leaves per bulb (8.56), leaf greenness (67.5 SPAD), root length (5.42 cm), polar bulb diameter (4.38 cm), equatorial bulb diameter (2.72 cm) fresh bulb weight (74.21 g), bulb yield (1751 t ha-1) and quality attributes like total soluble solids (TSS) (14.78 °Brix), ascorbic acid content (15.34 mg 100 g-1), pyruvic acid content (2.27 µmol g-1). However, soil test based application of 100% NPK ha-1 as TNAU-WSF was found to be an ideal rate to attain the economic target yield of the onion crop.

Impact of TNAU-Water Soluble Fertilizers (TNAU-WSF) on Soil Nutrient Availability, Nutrient Content and Bulb Quality of Small Onion (Allium cepa var. aggregatum)

“…Sulphur availability at 60 and 90 DAS was recorded high with soil test based fertigation of TNAU-WSF at 75% (T 5 ), 100% (T 6 ), and 125% (T 7 ) NPK with sulphur and TNAU LMM (1%) than fertigation of TNAU-WSF at 75% (T 2 ), 100% (T 3 ), and 125% (T 4 ) NPK which recorded low S availability. Higher availability of S was due to additional sulphur application [23,24,25]. Micronutrient availability showed non-significant differences between means of treatments because of no external application of micronutrients to soil [26].…”