Tomato varieties were evaluated during winter-spring growing season at experimental station of the Uzbek Research Institute of Vegetable, Melon Crops and Potato (UzRIVMCP). Six hybrids and one conventional cultivar were tested in Korean double-layered, single-span plastic greenhouses. These greenhouses were built under Uzbek-Korean collaborative research project. Variety trials were carried out to evaluate and select most suitable tomato varieties for growing in specific microclimate conditions which are created in double layered plastic greenhouses. Tomato hybrids F1 Beton and F1 Chelbas had significantly higher total and marketable yields compared to standard variety, and these varieties will be recommended for The State Variety Testing for further evaluations.

This experiment was carried out to determine the effect of different spectrum conversion greenhouse films (red, blue, red+blue) to changing microclimate and subsequent effect on growth and quality of lettuce (Lactuca sativa L.), tomato (Solanum lycopersicum L.), and melon (Cucumis melo L.) Transmission of PAR (photosynthetic active radiation, 400-700 nm) under red, blue, and blue+red (BR) films was higher by 7.2, 7.6, and 5.8%, respectively, as compared with control greenhouse film. Light transmission in the 300-1100 nm wave band was 91.6% and 91.3% under red and blue films, respectively, compared to 86.4% under control film. Mean daytime temperature in greenhouse was slightly higher in red and blue film and mean night time temperature was higher in BR film. There were no significant differences in relative humidity among the films. Number of leaves and plant fresh weight of lettuce were higher under BR film. Total number of marketable tomato fruits was greater under blue and BR film and fruit weight was heavier under red and blue film compared to control film. Under BR and red film melon fruit weight was increased by 140 g and 80 g respectively, as compared to control film. Sugar content in melon and tomato fruits was not affected by covering films.