In the graduation thesis we studied whether cucumbers with a smooth shell are of better quality and have less seeds and thiner skin, which contain more vitamin E or tocopherol, than a classic cucumber with a warty shell. We designed and carried out 2 experiments: cultivation of cucumbers in the summer and early autumn period. We studied also whether the content of pigments and tocopherol in the cucumber shell varies depending on the cultivation period. We cultivated two varieties of salad cucumbers with the classical, warty shell 'Lanoverde' and 'Jazzer', and two varieties with a smooth shell 'Saladin' and 'Sakura'. We planted them in 4 repetitions, and in each repetition 4 treatments (4 varieties) were randomly arranged. The seedlings for the summer growing period were raised in April and transplanted on the 16th of May in a greenhouse. Technologically mature fruits were harvested, counted and weighed, at each harvest date. On the randomly selected fruit from each repetition, fruit mass, lenght and width, flesh thickness and length, flesh hardness, color of the shell, dry matter content and total soluble sugars in the fruit were measured. Fruit and peel were frozen for later measurements of carotenoids and tocopherol. Transplants for the autumn growing period was planted on the same bed, without preliminary preparation and the same crop measurements were carried out. The autumn harvest was completed in November. The largest total yield (from summer and autumn growing period) was measured with the 'Sakura' variety (119 t/ha). During the summer period cucumbers reached 60-101 t/ha, while the autumn yield was much lower (from 9 to 21 t/ha). The most carotenoids and tocopherols are found in the shell. Tocopherol α is most presented in the fruit flesh and ranged from 18.6 to 28.3 μg/100 g FW and from 292.3 to 417.4 μg/100 g FW in the fruit shell. During the summer period, tocopherol α in fruits was by 71 % lower in flesh and by 63 % lower in shell than during the autumn period.
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