Effect Of The Alternating Magnetic Field On Physiology And Biochemical Characteristics In Cucumis Melo L.cv Hetao

Cucumis melo L. cv Hetao is one of the most significant economic crops withhigh nutritional value in Inner Mongolia Hetao Area, which has won popularity inside andoutside the area. However, as a typical climacteric fruit, it is easy to deteriorate and decayafter harvest, thus limits its large-scale production. The current preservation technology ofCucumis melo L. cv Hetao has a certain defect and this problem has aroused wide concern.Alternating magnetic field is very common in daily life, but rarely used inpreservation technology. Magnetic field treatment is an attractive technology for easy-operate, non-toxic, low-pollution and non-chemical residues, therefore, it has broadapplication prospects.Phospholipase D (PLD) is a key enzyme in the process of phospholipid hydrolysis inplant cell membrane, which plays an important role in the structure and function of cellmembrane, but also in cellular signal transduction. In recent years, the adverse-resistantcharacteristics of PLD has become the research hotspot.In this study, the intensity and time of alternating magnetic field treatment of Cucumismelo L. cv Hetao were regarded as the index. The physiological and biochemical indicatorswere determined so as to obtain the optimal condition. At the same time, quantitative PCRwas used to measure the change of PLD expression. The main results were as follows:(1) Firstly, different intensity of the alternating magnetic field was used to thetreatment of Cucumis melo L. cv Hetao. Compared with untreated samples, the alternatingmagnetic field with intensity of180V resulted in reduced respiration rates and delayeddecomposition, slowed the flow of titratable acid, while improving the frimness andsoluble solids content. It could be found that the magnetic field with strength of180V wasthe best for maintaining good quality of Cucumis melo L. cv Hetao.(2) Secondly, different time of the alternating magnetic field was used to the treatmentof Cucumis melo L. cv Hetao. Compared with untreated samples, the alternating magnetic field with treating for15min resulted in reduced respiration rates, lower electrolyteleakage, delayed softening and decomposition, slowed the flow of titratable acid, andreduced flows of soluble solids. The results showed that the magnetic field with treatingfor15min was the best for maintaining good quality of Cucumis melo L. cv Hetao.(3) Thirdly, the quantitative PCR technique was used to detect the change ofexpression of PLD gene in Cucumis melo L. cv Hetao, which was treated by the differenttime of the alternating magnetic field. The results showed that when the treating time was15min, the expression of PLD gene was the lowest. Under this condition, the Cucumismelo L. cv Hetao could maitain a good quality.To sum up, application of the alternating magnetic field prior to storage, especiallywhen the treating intensity of180V, treating time for15min, showed beneficial effects onreducing negative responses and delaying ripening in Cucumis melo L. cv Hetao.