تاثیر گاز دی اکسیدکربن روی سفیدبالک گلخانه (Hem., Aleyrodidae)Trialeurodes vaporariorum Westwood و خصوصیات کیفی میوه توت فرنگی

One of the most important greenhouse pests is Trialeurodes vaporariorum (Westwood) that can cause significant damage to greenhouse crops. In order to control this pest, various pesticides are used. In addition to their dangers to consumers, these pesticides may also have an adverse effect on fruit quality. Carbon dioxide is a substance derived from nature and its use does not have an adverse effect on the environment. The use of carbon dioxide is effective in the management of some pests; especially stored-grains pests.A study was conducted in greenhouse conditions in order to investigate the effect of carbon dioxide in the control of T. vaporariorum and its effect on the quality and chemical characteristics of strawberry fruit. The effect of carbon dioxide on the mortality rate of adult Trialeurodes Vaporariorum (Westwood) in 5 commercial strawberry cultivars (Kurdestan, Hummi Gento, Queen Eliza, Camarosa and Selva) was examined in different concentrations (200,400,600,800,1000 and 1200 parts per million (ppm)) in two time periods of 24 and 48 hours in 10 replications, and each replicate was tested 20 adult insects (one or two days old). An isolated room having a size of 36 square meters was used for the tests. Carbon dioxide was supplied from a 20 liter capsule equipped with a manometer. The effect of carbon dioxide on the quality and chemical properties of strawberry fruit was also studied. In order to evaluate the quality properties of strawberry fruit before and after the treatments, 20 evaluators (10 males and 10 females) were used in a taste test based on the standards of National Standards Organization. The results showed that T. vaporariorum losses started 24 hours after the treatment in the concentration of 600 ppm and increased with increasing carbon dioxide concentration. The losses started 48 hours after the treatment in the concentration of 400 ppm and increased with increasing concentration. T. vaporariorum losses did not show a significant difference in the studied cultivars. After 24 hours, the levels of LC50 of carbon dioxide of the T. vaporariorum fed with Kurdestan, Queen Eliza, Camarosa, Selva, and Hummi cultivars were 742.37, 733.74, 729.79, 732.23, 741.24 ppm, respectively, and after 48 hours, they were 632.87, 630.56, 640.28, 643.61 and 638.28 ppm, respectively. No significant effect was observed in evaluating the quality characteristics (aroma, color, sweetness, sourness, hardness, crispness and general acceptance) of strawberry fruit in different concentrations of carbon dioxide within 24 and 48 hours after the treatments. The results of chemical studies revealed that by increasing the amount of carbon dioxide, significant differences were observed in the amount of moisture, ascorbic acid, anthocyanin, dry matter percentage, ash, reducing sugar and potassium of different strawberry cultivars.