Improvement of regeneration from cotyledon of cucumber plant under the conditions of gene transfer with Agrobacterium tumefaciens

Improving regeneration and inoculation with Agrobacterium is one of the important goals of transgenic cucumber (Cucumis sativus) and for this purpose, the simultaneous effects of cold pretreatment, different concentrations of amino acid arginine and the size of the explants on regeneration in the conditions of inoculation with Agrobacterium were evaluated. According to the results, the interaction effect of cold pretreatment and arginine and the simple effect of arginine for the number of days to explant regeneration with complete cotyledons were significant with a confidence level of five percent, and divided explants did not regenerate. Using a concentration of 1000 mg/liter of arginine decreased the days to generation by 12.63%, but the concentration of 500 mg/liter of arginine increased the days to generation (by 17.92%). The lowest number of days until regeneration was observed in cotyledons treated with 1000 mg/L arginine in conditions without cold pretreatment (with 16.17 days) and the highest in the treatment of 500 mg arginine in conditions of cold pretreatment (25.33 days). For the characteristic of shoot growth rate, only the simple effect of arginine was significant at the level of one percent, the result of analysis of variance showed the interaction effect of cold stress and amino acid to be significant at the level of five percent. It can be said that the use of arginine at the rate of 1000 mg/liter in the medium of cucumber regeneration or cold pretreatment can help both regeneration and shoot growth.