Effect of planting density and nutrients on bulb development and flowering in seed propagated onion (Allium cepa L.var. aggregatum Don.) type Gnanamedu local

Abstract

An experiment was conducted at Horticultural College & Research Institute to find out the response of aggregatum onion to different spacing and levels of organic, inorganic and biofertilizers in respect of bulb diameter, bulb length, shape index and flowering. The experiment was laid out in split plot design with 30 treatments replicated thrice. Three spacing viz., S, 45x5, S, 45x10, and S, 45x15 cm formed the main plot treatments. The subplot treatments consist of 10 combinations involving three levels of N (20, 40 and 60 kg ha), three levels of P (20, 40 and 60 kg ha') and constant level of K (30 kg ha) along with FYM 25 tha, Azospirillum at 2 kg ha' and phosphobacterium at 2 kg ha'. An organics alone and absolute control without nutrients were also adopted. The increase in length of bulb and shape index were higher at closest spacing of 45x5 cm, while the widest spacing of 45x15 cm registered the greater bulb diameter. Manurial treatments had significant influence on the bulb characters, which showed an increasing trend with increasing level of nutrients. Spacing and nutrients had no influence on the days taken for flower initiation, days to 50 per cent flowering and days for maturity. Interaction effect revealed that application of 60:60:30 kg NPK ha, FYM. at 25 t ha, Azospirillum at 2 kg ha and phosphobacterium 2 kg hat along with closest spacing of 45x5 cm recorded the higher bulb length (5.70 cm) and shape index (1.09 %).

DOI

https://doi.org/10.29321/MAJ.10.A00349

Pages

382 - 385

Creative Commons

Copyright

© The Author(s), 2025. Published by Madras Agricultural Students' Union in Madras Agricultural Journal (MAJ). This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited by the user.

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