Abstract:
An experiment was conducted at the laboratories of the Plant Physiology section of the
Horticulture Research Centre (HRC) and Post Harvest Laboratories under the Bangladesh
Agricultural Research Institute (BARI), Joydebpur, Gazipur, during the period from
January to March 2005 to study the effects of different stages of maturity and different
concentration of ethrel treatments on changes in ripening and quality of tomato fruits
during the postharvest storage. Fruits of three maturity stages viz. mature green, breaker
and half-ripe were treated under three ethrel concentrations viz. control, 500 ppm ethrel
and 1000 ppm ethrel.
Different maturity stages, ethrel treatments and their combinations showed the highly
significant variation on ripening and quality of tomato. The half ripe tomato treated with
1000 ppm ethrel gave quick colour development (3.00 days) and the highest vitamin-C
(12.46 mg/lOOg tomato pulp), titrable acidity (0.456%) reducing sugar (4.50%), non
reducing sugar (I.70%), total sugar (5.07%) and TSS (5.50%) at final day of observation
and the mature green tomato treated with 1000 ppm ethrel showed maximum days of
shelf life (37.00 days) and showed the highest pH (4.71) at the 500 ppm ethrel treatment.
On the other hand, the mature green tomato under control treatment showed the highest
weight loss (14.92%) at the final day of observation. The mature green tomato under
control conditions showed the delay colour development or ripening (15.00 days) and the
lowest vitamin-C (3.68 mg/lOOg tomato pulp), reducing sugar (3.85%) and TSS (4.49%)
at the final day of observation. Half ripe tomato treated with 1000 ppm ethrel showed the
lowest weight loss (14.00%), pH (4.26) and non-reducing sugar at the final day
observation and green mature tomato treated with 500 ppm ethrel showed the lowest
titrable acidity (0.443%) and total sugar (4.73%) and half ripe tomato with control
treatment showed the lowest shelf life (20.00 days).
From the investigation, it may be concluded that for early ripening half-ripe tomato
treated with 1000 ppm ethrel is the best and to extend the shelf life, mature green tomato
treated with 1000 ppm ethrel is the best. On the other hand, weight loss and other physio
chemical characteristics were found to be the highest when half-ripe tomatos were treated
with 1000 ppm ethrel.