Tropentag, October 6 - 8, 2009 in Hamburg "Biophysical and Socio-economic Frame Conditions for the Sustainable Management of Natural Resources"

Effect of Ethrel Postharvest Applications on Ripening of ‘Tron' and ‘Hoi' Mangoes (Mangifera Indica L.)

¹University of Hohenheim, Department of Special Crops and Crop Physiology, Germany
²Hanoi University of Agriculture, Horticulture, Viet Nam
³Chiang Mai University, Department of Horticulture, Thailand

Abstract

Mango (Mangifera indica L.) is becoming an important fruit crop in the mountainous areas of Son La Province in northern Vietnam. The two main local varieties ‘Tron' and ‘Hoi' have great potential for commercial mango production, but their cultivation is restricted to the hillsides areas of Son La Province. Commercially harvested fruit is relatively soft and has a short shelf life. In contrast, green mangos are firm and withstand well transportation to remote markets but require long time to reach full ripeness. An effective technology for overcoming this production and marketing constraint and thus combining excellent transportability and uniform ripening of fruit could be the postharvest application of Ethrel.
Consequently the research objective was to investigate the effect of Ethrel applied as postharvest aqueous solution on various fruit ripening parameters of 'Tron' and ‘Hoi' mango. In 2008 fruit of five ‘Tron' and ‘Hoi' trees from each of five orchards, respectively, were collected at commercial harvest and 10 days prior. Fruits were trenched for 30 min in 0.4% and 0.8% Ethrel solution and water as control treatment, then dried at room temperature, kept in sealed plastic boxes and stored at 20°C and 12°C with a relative humidity of approximately 70%. At each removal date of 1, 3, 5, 7 and 9 days of storage time, fruit samples were kept over 24 h at 20°C before fruit quality assessment commenced. In general, fruit weight loss was significantly less at 12°C than at 20°C. In addition, fruit of both cultivars treated with 0.8% Ethrel and kept at 12°C had greater weight loss than other treatment fruit at the same room temperature. Flesh firmness of ‘Hoi' was maintained higher and longer compared to ‘Tron' but was more reduced at higher concentrations of Ethrel in both temperature regimes. total soluble solids concentration of ‘Hoi' was considerably increased with increasing Ethrel concentration within five days at 12°C and three days at 20°C. Moreover, skin and flesh hue angle of ‘Hoi' enhanced significantly at higher Ethrel concentration under both temperature regimes. The results showed that 0.8% Ethrel accelerated ripening of both cultivars.

Keywords: Fruit colour, fruit weight, total soluble solids concentration

Contact Address: Vu Thanh Hai, University of Hohenheim, Department of Special Crops and Crop Physiology, Emil-Wolff-Str 25, 70593 Stuttgart, Germany, e-mail: vuhaihauyahoo.com