Establishment of efficient adventitious shoots induction system and ex vitro rooting in Vaccinium corymbosum (Ericaceae)

Abstract

<p align="left"><strong>Background</strong>: The extension of the blueberry industry in China is restricted by the low performance of proliferation coefficient, transplanting survival rate and the long cycle production.</p><p align="left"><strong>Hypothesis</strong>: We hypothesized the suitable medium with optimal concentration and type combination would improve the survival rate of <em>Vaccinium corymbosum.</em></p><p align="left"><strong>Species studied</strong>: <em>Vaccinium corymbosum</em> L. cultivar ‘O’Neal.</p><p align="left"><strong>Study site and years of study</strong>: Our study was conducted in Yunnan Breeding and Cultivation Research and Development Center of Endangered and Daodi Chinese medicinal materials, Yunnan University of Chinese Medicine since November 2015.</p><p align="left"><strong>Methods</strong>: Efficient protocol of plant regeneration about Southern highbush blueberry (cultivar ‘O’Neal) was established using annual shoots via single factor and orthogonal experiments.</p><p align="left"><strong>Results</strong>: Olive medium with 2.0 mg·L^-1 zeatin was found to be most suitable for initiation culture. The highest callus induction and bud formation rate were determined with 93.67 % and 95.57 %, respectively. Furthermore, as the germination of axillary buds, numerous shoots were formed with the proliferation coefficient (&gt; 60). Well-developed shoots were obtained using rejuvenation culture on half-strength Olive medium supplemented with combination of 2.0 mg·L^-1 indole-3-butyric acid, 1.0 mg·L^-1 naphthaleneacetic acid, 0.01 mg·L^-1 chlormequat chloride and 0.5 g·L^-1 activated charcoal. The rooting rate could reach to 100 % using 2 cm length of well-developed shoots transferred into the 5:1 sterilized peat:perlite, which was enhanced from 27.61 up to 95 % after transplanting to the field.</p><p align="left"><strong>Conclusions</strong>: An efficient system for plant regeneration from bud induction to transplanting to the field was established to maintain the characteristics of southern highbush blueberry varieties.</p>