In Vitro Culture And Rapid Micro-propagation Of Kiwifruit (Actinidia Eriantha 'White' And Actinidia Chinensis 'Hongyang')

Kiwifruit is a new fruit with rich nourishment known as the "king of fruits". It is very popular owing to its special flavor and rich nourishment especially high content of Vitamin C. 'White' is a new and large-fruited kiwifruit cultivar which selected from the wild plants of Actinidia eriantha Benth by Institute of Horticulture, Zhejiang Academy of Agricultural Sciences, etc. Vitamin C content in its fruits of 568.9～1137.0 mg/100g·FW is higher than other kiwifruit species. It is sometimes referred to as the'banana kiwifruit' because the skin is very easy to peel. Actinidia chinensis'Hongyang' is one of the Chinese endemic wild kiwifruit resources-series of red meat kiwifruit (Actinidia chinensis var. rufopulpa).'White' and 'Hongyang' kiwifruit as valuable resources have vast market prospects and grate value of development and utilization.In this study, various explants from kiwifruit (Actinidia eriantha'White'and Actinidia chinensis'Hongyang') were used for in vitro regeneration. Established stable and efficient plant regeneration systems will help facilitate the application of genetic engineering methods to improve the commercial traits in A. eriantha and A. chinensis. The main results are summarized as follows:1. Established a stable and efficient rapid propagation system for A. eriantha 'White' by means of the field materials and in vitro cuttings tissue culture.1) To get regenerated buds from callus, the immature leaves was the optimum explant. To compare the re-differentiation of adventitious shoot regeneration from leaf, petiole, root segment and mesocarp callus, the regeneration rate of adventitious shoot from leaf callus was 85.33%, the second was 79.17% from petiole callus. However, it was 0 from root segment and mesocarp callus. Bud regeneration ratio was 100% from the bottom one third of the immature leaf by futher studied on the different leaf type and site, its length was less than 3 cm. 2) Take leaf and petiole as explants, the MS medium supplemented with 2.0 mg/L 6-BA and 0.1 mg/L NAA was the best one for leaf, with callus formation rate of 100% and bud regeneration rate of 85.33%, the number of shoots averaged 6.34 per explant. The optimum medium for petiole was MS containing with 2.0 mg/L ZT plus 0.1 mg/L NAA, callus formation rate was 100% and bud regeneration rate was 79.19%, the number of shoots averaged was 6.54 per explant.3) Direct induced axillary bud sprouting, the no-lignified branches was the optimum explant and the most fitting season to gather the stem was spring and summer. MS supplemented with 1.5 mg/L 6-BA and 0.1 mg/L NAA was more suit as axillary buds induced medium than the others. Rate of sprouting was 86.67%. The best medium for multiplication of the adventitious buds was 3.33 plantlets per explant in MS containing with 3.0 mg/L 6-BA plus 0.1 mg/L NAA.4) The best medium for in vitro rooting was 1/2 MS plus 0.6 mg/L IBA, the rooting rate was 96.67%, and 16.1 roots per plantlet. The results of used bryophytes wraped no-root plantlet caudex for ex vitro rooting was very good, ratio of rooting was 93.75%. The plantlets with roots were planted in the medium containing 1/3 perlite and 2/3 peat, the survival rate reached 92% after a month.2. Established a stable and efficient rapid propagation system from the female Actinidia chinensis 'Hongyang' immature leaves and stem segments with axillary buds in vitro cultured.1) Leaves were cultured for the initiating of callus, proliferation of adventitious buds. The results indicated that callus formation were easy and proliferation effciency was greatest when explants form leaves tissue were cultured on MS supplemented with 1.0 mg/L Zeatin and 0.1 mg/L NAA. The number of shoots averaged 5.2 per explant, representing an efficiency of 93.33%.2) Axillary buds were cultured for sprouting and multiplication.83.33% axillary buds sprouted buds on MS supplemented with 1.0 mg/L 6-BA plus 0.1 mg/L NAA; the best medium for the multiplication of the adventitious buds was 4.5 plantlets per explant in MS supplemented with 2.0 mg/L 6-BA plus 0.2 mg/L NAA and 0.1 mg/L GA acid.3) 1/2 MS with 0.7 mg/L IBA was good for rooting. The plantlets with roots were planted in the medium containing 1/3 perlite and 2/3 peat, the survival rate reached 90% after a month.