Mankar, Dr. A. N.JAMKAR, NARENNDRA SURESHRAO.2018-10-132018-10-132018-09-19JAMKAR, NARENNDRA SURESHRAO. (2018). Effect of spacing and fertilizer levels on onion production under drip fertigation. Department of Irrigation and Drainage Engineering, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. M. Tech. 2018. Print. xiv, 106p. (Unpublished).http://krishikosh.egranth.ac.in/handle/1/5810081043Crop geometry or spacing between plants, determines the plant density and is generally dependent upon the expected growth of a particular crop plant variety in a given agro-climatic region. Higher plant population can be achieved by reducing the distance between two rows or between two plants within the row. Besides crop geometry, the balanced fertilization is another important factor. Drip irrigation along with fertigation reduces the wastage of water and chemical fertilizers and subsequently optimizes the water and nutrient use by making them available at the point of their use and as per crop demand, which finally increase water and nutrient use efficiency.Drip irrigation along with fertigation reduces the wastage of water and chemical fertilizers and subsequently optimizes the water and nutrient use by making them available at the point of their use and as per crop demand, which finally increase water and nutrient use efficiency. This modern agro-technique provides an excellent opportunity to maximize yield and minimize environmental pollution such as leaching of nutrients and chemicals by increasing fertilizer use efficiency, minimizing fertilizer application and increasing return on the fertilizer invested. The field experiment to study the “Effect of spacing and fertilizer levels on onion production under drip fertigation” was conducted at Chilli and Vegetable Research Unit, CRS, Dr. PDKV, Akola, during Rabi season of 2017-18, which comes under Western Vidarbha Region of Maharashtra. The experiment, comprising of 9 treatment combinations replicated three times, laid out in factorial randomize block design with three spacing 10 x 7.5 cm, 10 x 10 cm, and 10 x 12.5 cm and three fertilizer levels (80%, 100% and 120% recommended dose of NPK). Plant spacing 10 x 12.5 cm was superior over different spacing in relation to growth attributes viz. number of leaves per plant, neck thickness, and average weight of bulb, polar and equatorial diameter of bulb. However, plant height, bulb yield per hectare and marketable yield was maximum under 10 x 7.5 cm spacing due to more number of plants accommodated per unit area but it was statistically at par with other spacing. Minimum rotten bulb was found with 10 x 10 cm spacing. 120% recommended dose of fertilizer significantly improved the growth (plant height, number of leaves per plant, average weight of bulb, polar and equatorial diameter of bulb). Whereas, 120% RDF revealed maximum marketable yield and minimum neck thickness which showed good quality parameter. Yield attributes i.e. bulb yield per hectare was maximum with 120% RDF which was statistically at par with other two fertilizer levels. Spacing and fertilizer levels showed significant effect on yield parameter (bulb yield per hectare and marketable yield) and their interaction was non-significant. The maximum bulb yield and marketable yield (q/ha) was recorded with F3S1 (120% RDF with 10 x 7.5 cm spacing) which was statistically at par with other treatment combination, except F2S1 (100% RDF with 10 x 7.5 cm spacing). Combine effect of two factors did not show any remarkable influence on growth parameter (plant height, no. of leaves and neck thickness), yield attribute (average weight of bulb, polar and equatorial diameter) and quality parameter (rotten bulb and TSS). The maximum net return with higher B:C ratio (2.74) was obtained in treatment combination F3S1 (10 x 7.5 cm spacing with 120% RDF). Because of maximizing the yield with closer spacing, application of maximum dose of fertilizer and considering the B:C ratio, the treatment combination F3S1 was best and can be recommended for maximum onion production in Western Vidarbha region.enAgricultural Engineering, Equipment, Irrigation Equipment, Fertilizer Equipment, Crops, Vegetable Crops, Allium cepa, Onions, Plant Production, Farming System, Irrigated Farming, Crop geometry, Fertilizer levels, Onion, Drip fertigation, B:C Ratio, Spacing, Agricultural Economics, Benefit-Cost Ratio, Statistical Methods, Experimental Design, Data Analysis,Thesis