Study On In Vitro Propagation Of Alocasia Cucullata And Its Microrhizome Induction

Alocasia cucullata is a kind of important indoor foliage plants, belongs to Araceae family. At present, there are few studies on Alocasia, relatively reports on Alocasia cucullata is even fewer. The liquid proliferation system, callus induction and regeneration conditions, microrhizome induction system in vitro and the best nutrient solution ex vitro of Alocasia cucullata was studied. The results as follows:1. Plantlets of Alocasia cucullata were used as material. An efficient system of poliferation was established through adding several kinds of plant growth regulators and other treatments. The results showed that low concentration of6-BA, especially MS containing1.0mg·L-1BA, had a better effect on poliferation, and NAA had no significant effect on plantlet poliferation; the optimal poliferation medium was MS+6-BA1.0mg·L-1+NAA0.5mg·L-1, liquid culture for2weeks in100ml receptacle volume, then transferring into solid culture for another2weeks; and with bigger plantlets, it had more lateral buds.The simple efficient method of production of plantlets is useful for large-scale multiplication of this important ornamental plant.2. Stems of Alocasia cucullata as material, cutting the surrouding buds. The effect of different concentrations ratio of cytokinin and auxin, basal medium, sucrose concentration and illumination condition on callus induction and plant regeneration of Alocasia cucullata were studyed. The result shows that the optimal poliferation medium was using1/2MS as basal medium, adding6-BA1.0mg·L-1and NAA0.5mg·L-1or KT0.5mg·L-1and2,4-D1.0mg·L-1, with15g·L-1sucrose, and dark culture for4weeks.3. Plantlets of Alocasia cucullata were cultured on the MS medium supplemented with different concentrations sucrose, SA and PP333. The results showed that sucrose supplies of60,90and120g·L-1hampered generation of leaves but induced formation of microrhizome. The survival ratio of plantlets grown with sucrose supply were100%, while those with no sucrose supply was only6.77%after30days ex vitro. Plantlets shows no difference supplemented with different concentrations of SA no matter in vitro or ex vitro growth period. The effect of PP333was like effect of sucrose, there was dormant structure when supplied with8.0mg·L-1PP333. Thus it was showed that60g·L-1sucrose supply was a better concentrations for both microrhizome induction and ex vitro growth of Alocasia cucullata plantlets. Microrhizome induction order of Alocasia cucullata:sucrose> PP333>SA.4. The effects of different nutrient solutions on growth of Alocasia cucullata micropropagation plants in greenhouse were investigated by analyzing growth parameters and physiological indexes. The results indicated that E nutrient solution (N:P:K=21:2:9) showed best on morphological and physiological indexes except chlorophyll content. The other four treatments showed no significant difference with each other. Contacted with tap water, Alocasia cucullata which spplyed with five nutrient solutions all showed better on growth. In conclusion, nutrient solution E was the best nutrient solution for Alocasia cucullata.