Studies On Bio-effects And Genetic Transformation Of Muskmelon Induced By Low Energy Ar～Ions Implantation

In this paper, the biological effects of different doses Ar+ ion implantation on Cucumis melo L were studied in order to search the relationship between ion implantation and Cucumis melo L. Using the ion beam mediated transgenic method to transfer NP-1 gene into seeds of cantaloupe. Seeds of Jiashi cantaloupe and Huanghou cantaloupe were implanted by Ar⁺ ion beam, energy was 25keV, doses were 0, 2×10¹⁶ Ar⁺/cm²,4×10¹⁶ Ar⁺/cm²,5×10¹⁶ Ar+/cm²,6×10¹⁶ Ar⁺/cm²,7×10¹⁶ Ar⁺/cm². The results are as following: (1) After having observed the germination of seeds implanted by ion beams, the results showed that Ar+ implantation restrained the germination of cantaloupe seeds with the doses increasing. (2) Some physiological and biochemical indexes were analyzed, such as the activities of POD,CAT,SOD,ASP ,generating rate of O₂ and the content of H2O2,ASA,MDA, etc. the results indicated that ion implantation induced damnification, produced lots of free radical and lead to the activities of cell defense enzymes and no-enzymatic antioxidants increasing. The increasing activities of cell defense enzymes make the degree of membrane lipid peroxidation decrease. But with the doses increasing, the enzymatic and no-enzymatic protection mechanisms were destroyed and lead to the accumulation of MDA. (3) Analysed the peroxidase isozyme bands of the cantaloupes, we can see that Ar+ implantation caused the mutation of quantity and activity in peroxides isoenzyme. (4) Exogenous NP-1 gene was introduced into cantaloupe seeds by ion implantation. The results of molecular detection proved that exogenous gene had integrated into cantaloupe tissue culture. The experiments proved that Huanghou cantaloupe is more sensitive than Jiashi cantaloupe. So in future we should choose the best implantation parameters according to different cantaloupes in mutation breeding.