In vitro propagation of Diyarbakir watermelons and comparison of direct-seeded and transplanted watermelon

Abstract

A rapid protocol using shoot tip explants for micropropagation of Diyarbakir watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] types Surme, Beyazkis and Karakis was achieved. Shoot tips from 5-day-old in vitro germinated seedlings were cultured on shoot regeneration medium for 3 weeks. The effects of the different concentrations of benzyl adenine (BA) and carbohydrate types on shoot proliferation were examined. The results confirmed that a range of 0.5-1.0 mg/L of BA was almost equally effective in promoting the shoot length of cultures in the 3 genotypes. Sucrose, in the presence of BA, was superior to other carbohydrates for the 3 genotypes studied in terms of the number of proliferated shoots and the average shoot length obtained. The highest percentage of rooting was achieved when medium supplemented with 1.0 mg/L of indole-3-butyric acid (IBA) was used for the 3 genotypes. The highest frequency of acclimatized plantlets for the 3 genotypes was 85%, 85%, and 90%, respectively, in sterile compost, when the shoots of Beyazkis, Karakis, and Surme were rooted in the IBA-supplemented rooting treatments. The Surme genotype produced a significantly higher yield and mean fruit weight than the Beyazkis and Karakis genotypes in both direct-seeded and transplanted watermelons. The main soluble sugar of the experimental types was separated, identified, and quantified using high performance liquid chromatography (H PLC). Fructose was found to be the most abundant sugar and was highly detected in Beyazkis for the seeded watermelon and in Karakis for the transplanted watermelon. This demonstrates that in vitro propagation can be used to produce high quality diploid Diyarbakir watermelon for use in breeding lines.