Effect of magnetic field-free space on growth characteristics of alfalfa

Magnetic field-free space mutagenesis is a breeding method of analog space zero magnetic field on the ground. To study the effect of magnetic field-free space mutagenesis on growth characteristics of alfalfa, four alfalfa cultivars were used as experimental materials, the seed vigor was determined, and agronomic characters and physiological indexes of contemporary plants were studied after treatment by magnetic field-free space mutagenesis for 180 days. The results showed that the seed germination was obviously inhibited by magnetic field-free space mutagenesis treatment, while the influences on seedling length and root length varied among different varieties. What' s move, magnetic field-free space mutagenesis treatment showed different influences on the agronomical characteristics among these four varieties for Xunlu and Longmu 806, the plant height were inhibited, while for Zhaodong and Aohan alfalfa, the plant height were promoted. The branch number and biomass production of all alfalfa varieties were also promoted, but the stem-leaf ratio showed the downward trend, and there were no obvious effects on dry-fresh ratio. After treating with magnetic field-free space mutagenesis, the peroxidase (POD) activities of all alfalfa leaves were increased. The activity changes of superoxide dismutase (SOD) and hydrogen peroxidase (CAT) were different among different varieties. There was no obvious effect on concentration of malondialdehyde (MDA). That indicated the induced mutation was dependent on the varietyies. The magnetic field-free space mutagenesis treatment can improve agronomic traits of contemporary alfalfa, and provide technical reference for the good offspring mutant strain breeding. (authors)