Studies on the Changes of Physiological Properties of Conservation of Eucalyptus Germplasm Encapsulatied in Alginate Beads at Room Temperature

Respiration,chlorophyll,soluble protein,activities of peroxiase(POD)and polyphenol oxidase(PPO)during the 9 months conservation of Eucalyptus microcuttings encapsulated in alginate beads were examined.The synthesis of chlorophyll and protein occurred in alginate beads of microcuttings of Eucalyptus during the earlier stage of conservation. The maximum chlorophyll and soluble protein were found in the second month or fourth month,respectively,then degraded. Respiration of microcuttings in alginate gel beads was inhibited and decreased with conservation time.The activity of PPO increased at first,then decreased in the end of conservation,but the activity of POD suddenly dropped in the beginning,then reduced slowly.When sucrose was added to the alginate gel, the change patterns of chlorophyll and soluble protein in the microcuttings were similar to that of sucrose free gel,but protein content increased and the POD activity showed a marked reduction with the increasing concentration of sucrose.The results indicated that low concentration of alginate(1.5%)and sucrose(0.5 %)were favored to the slow synthetic metabolism,which might be as the physiology base of storing microcuttings of Eucalyptus under “minimal growth” condition of tissue culture.