Modern NHRDF onion storage structure under sub-tropical conditions

Abstract

In India onion is produced in three season’s kharif, late
kharif and rabi, in which rabi harvest have good keeping
quality and can be stored for longer period up to 5-6 months.
Over a period of storage, there is a gain of three to four
times profit in market due to non-availability of onion.
Hence, the storage of onion is very essential to maintain
regular supply to the consumer till November. Due to
improper storage, more losses arise in farmer’s storage
method due to higher sprouting, rotting and physiological
loss in weight, which leads to heavy stress on both demand
and supply resulting in a steep rise in the price. Scientifically
developed storage facilities will help in checking the supply
volatility and rise in onion prices. Under existing ambient
conditions, NHRDF has developed a ventilated conventional
onion storage structure providing proper aeration and
ventilation without any control on temperature and humidity.
This storage structure is popularized in major onion growing
states in India. Recently, the NHRDF has developed an
improved storage structure designed to maintain the
constant temperature and relative humidity throughout the
storage period. After six months of storage, highest quality
bulb recovery (21.40 ton), with lowest rotting (0.69%),
physiological loss of weight (13.83%) and total loss (14.52%)
were recorded in NHRDF improved onion storage structure.
Due to highest bulb recovery, highest net returns are
obtained. While in NHRDF conventional ventilated storage
structure, moderate quality bulb recovery (16.70 ton),
sprouting (2.50%), rotting (10.10%), physiological loss of
weight (20.80%) and total losses (33.40%) were recorded.
The lowest quality bulb recovery, highest sprouting, rotting,
physiological loss of weight and total loss were recorded in
farmer’s storage structure. Apart from these, NHRDF
improved onion storage structure has several advantagesover

cold storage structure, conventional ventilated storage
structure and farmer’s storage structure.