Multiplier onion (Allium cepa L. var. Aggregatum Don.) is an important commercial vegetable crop grown in Ariyalur and Perambalur districts of Tamil Nadu. Inorganic fertilizer inputs are proven to be harmful in long-term impacts. Use of organic manures to meet the nutrient requirement of crop would be an inevitable practice in future as organic manures gradually improve the soil physical, chemical and biological properties along with conserving the moisture holding capacity of soil. Although organic fertilizers are lesser amount of nutrient than that of inorganic fertilizers, presence of growth promoting substances like enzymes and hormones make organic manure vital for improvement of soil fertility and productivity. Present study was carried out to evaluate the response of different organic source of nutrients to multiplier onion CO (On) 5 during 2017-18. The observations were recorded on five randomly selected plants and bulb yield on plot basis in each replication on growth, yield parameters and BCR. The experiment was laid out in a Factorial Randomized Block Design which included 15 treatments each of which was replicated thrice. Among the different levels of treatments, significant increase in yield parameters was found in treatment T₉, application of vermicompost 5 t ha^-1 along with bio fertilizer (Azospirillum, phosphobacteria, Potash mobilizing bacteria and Sulphur oxidizing bacteria each @ 2 kg ha^-1 + VAM @ 12 kg ha^-1) and spraying of bio stimulant seaweed extract (0.1%) gave the maximum Bulb weight/ clump (14.22 g), plant height (25.73cm), Number of leaves/plant (11.46 Nos.), equatorial diameter of the bulblet (1.80 cm), polar diameter of the bulblet (2.48cm), bulb yield (9.40 t ha^-1). The next best treatment was T₁₄ treatment application of vermicompost 5 t ha^-1 along with bio fertilizer (Azospirillum, phosphobacteria, Potash mobilizing bacteria and Sulphur oxidizing bacteria each @ 2 kg ha^-1 + VAM @ 12 kg ha^-1) and spraying of bio stimulant Panchagavya (3%). The results revealed that the overall performance of Treatment T₉ was superior to all the other Treatments and this organic cultivation package is recommended in Ariyalur district, Tamil Nadu.

Download this article as