Effect of pre and post-harvest treatment with plant extracts and calcium chloride on storage ability of tomato Lycopersicon esculentum Mill. fruits grown in plastic greenhouse

摘要

The experiment was conducted in one of the greenhouses of the Agricultural Research Station, College of Agriculture, University of Basrah, Karmat Ali site during the growing season of 2015- 2016 in order to improve the storage behavior of tomato fruits hybrid Wegdan. The seedlings were planted in the plastic house on 20/10/2015 and all the processes using in the production of this crop were conducted. Water extract of licorice (Glycyrrhiza glabra L.) at three concentrations (zero, 2, 4 g L-1 ) was prepared and the plants were sprayed in the early morning three times starting from 5/11/2015 with a time interval of two weeks from the date of planting for the first spray and the operation returned after 10 days. Fruits were harvested at mature green stage in the early morning and brought to the laboratory of storage technology, then cleaned and soaked in water extract of garlic with concentration of 4%, calcium chloride solution with concentration of 4% in addition to control treatment (distilled water only) for a period of 10 minutes and left to dry at room temperature. A portion of harvested fruits that was sprayed with the water extract of G. glabra at the concentrations of (zero, 2, 4 g L-1 ) were left without soaking. All the fruits were packed in perforated polyethylene bags (16 hole with a diameter of 5 mm per bag and weighed 2 kg per bag). Then the samples were stored at the temperature of 13掳C for four weeks. Results indicated that the decay percentage, the percentage of weight loss and the percentage of total soluble solids increased while the amount of vitamin C decreased with an increment of storage periods. The lowest percentages of the decay and weight loss and the highest percentage of total soluble solids were in fruits treated with G. glabra extract as compared with untreated fruits. Fruits treated with garlic extract recorded the lowest percentage of decay and lowest percentage weight loss, while fruits soaked in 4% calcium chloride solution gave the highest percentage of total soluble solids. The interaction among spray treatments with G. glabra extract, post-harvest soaked treatments with garlic extract and calcium chloride and the storage period was significant. Fruits sprayed with 4 g L-1 G. glabra extract, soaked in 4% garlic extract, were undamaged up to the end of the third week of storage