Response of strawberry plants and fruits to gamma irradiation as a supplementary factor preceding tissue culturing of strawberry transplant [electronic resource].

Includes reference.

The transplant of strawberry (c.v. Rosa linda) were irradiated using 8 doses of gamma rays ranged from 50 to 500 Gray, to study the effect of a wide range of applied gamma irradiation. Then tissue culture technique was applied on irradiated and un-irradiated (control) strawberry transplant. Data revealed that the relatively low radiation doses i.e. 50, 75 and 100 Gray, increased all morphological and chemical characteristics of plantlets, plant and fruit of strawberry. Doses higher than 100 Gray, decreased them significantly and gradually by increasing radiation doses. Moreover, the relatively high doses i.e. over than 250 Gray, were lethal doses and did not permit any of the growth parameters. It is worthy to mention that the radiation dose of 50 Gray, was the optimum dose, since it has increased the survival percentage by 1.5% compared with control and resulted in the tallest plantlets in the three multiplication stages, and gave 25% increasing in the plant height. In addition, the highest number of leaves/plant, fruits/plant, the largest leaf area and crown diameter were also obtained by the same dose of 50 Gray. There were no significant differences in moisture content of leaves, stems and dry matter, whereas, the ash content showed significant increases under the influence of low radiation doses. Significant increasing in chlorophyll b and carotenes concomitant with decreasing in chlorophyll a was detected. Concerning strawberry fruits, the data showed increases in fruit size, fruit firmness, vitamin C, acidity, TSS and TSS/acidity. On the other hand, there were no significant changes in juice pH and dry matter content. For the fruit yield, the obtained data revealed 46% and 51.9% increasing in the early and total yield of strawberry fruit respectively under the influence of the low radiation dose of 50 Gray,. In addition, 56.4% increasing in the total fruit yield was obtained from the plants irradiated with 75 Gray, dose of radiation. Finally, from both economic and biological point of view it is quite clear that gamma irradiation with low and safely doses ranged from 50 up to 100 Gray, help the tissue culture technique applying to strawberry transplant successfully for producing good plantlets which led to good plants and finally resulting in high yield with high quality of strawberry fresh fruit, either for local consumption and/or for export. Key words: Strawberry plant- plantlets- gamma irradiation- tissue culture- morphological characteristics- exportable fruit yield.

Summary in Arabic.

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