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Gene escape and fruit quality characteristics of transgenic melons (Cucumis melo L. var inodorus cv. 'Kirkagac 637') resistant to zucchini yellow mosaic virus (ZYMV) and control plants were investigated under screenhouse conditions. No significant differences were observed between transgenic and transgenic × control genotypes, with regard to rind thickness, fruit cavity length, fruit cavity width, total soluble solids, pistil scar diameter, and peduncle length. Fruit characters, including fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter were significantly different. These results indicate that transgenic × control genotypes had higher values than transgenic (T4 and T20) genotypes, regarding fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter. Significant differences were not observed between transgenic (T4 and T20), control, and transgenic × control genotypes in terms of L-ascorbic acid, malic acid, citric acid, sucrose, glucose, or fructose, but differences were observed for fruit total acidity. Esters, lactones, and alcohols were aroma components, but none differed significantly between the transgenic and control genotypes. The results show that there was 100% gene escape in the control plants within 10 m of the transgenic plants, while there was 70% gene escape in plants 12.5, 15, and 17.5 m from the transgenic plants under screenhouse conditions.

In vitro morphogenesis of Cucumis melo var. flexuosus (L.) Naudin was studied by direct organogenesis. Induction of adventitious buds was obtained from distal and proximal parts of the cotyledon incubated on Murashige and Skoog (1962) medium containing different concentrations of 6-benzyladenine (BA) (0.0, 0.5, 1.0, and 2.0 mg L-1) and indole-3-acetic acid (IAA) (0.0, 0.1, and 0.5 mg L-1). The best organogenesis was obtained from the proximal part of the cotyledon on medium containing 0.5 mg L-1 BA and 0.5 mg L-1 IAA (88%). This concentration was used for histological analysis. Less regeneration was obtained on media containing 1.0 mg L-1 BA (75%) or 1.0 mg L-1 BA and 0.1 mg L-1 IAA (60%). Plant recovery was much greater from proximal rather than distal explants. A callus formed on almost every explant on media supplemented with BA. Histological analyses showed that the formation of early shoot apical meristems was observed in 14-day-old tissues and meristematic structures were seen in 17-day-old tissues. The first shoot was formed after 21 days. By this time, the surface was covered with leaf primordia and leaves, mostly without accompanying buds.

Axi 1 is the only characterized auxin independent gene in tobacco plants. In this study, the effect of axi 1 gene on cortical cell division during different stages of nitrogen fixation and on the role of polar auxin transport were investigated. Root and nodule samples were taken from pea seedlings 24 hours, 48 hours, 6 days and 10 days after inoculation with R. leguminosarum PRE strain. Using in situ hybridisation, the location of the axi 1 gene expression in root and nodule tissues was identified. The results showed that in root tissues inoculated with Rhizobia, the axi 1 gene is expressed on the phloem tissue of the vascular bundle. In the 10-day-old nodule tissues, the gene expression was found in the phloem tissue, around the nodule bundle and nodule meristematic region. The results obtained indicate that also Axi 1 gene plays a role in nitrogen fixation and auxine transport.