In Vitro Methods to Propagate Tea (Camellia sinensis)Accessions

摘要

Tea [Camellia sinensis (L.) O. Kuntze] is a globally recognized beverage crop. It is being tested as an alternative for citrus in Florida, as the species can grow well in sandy, acid soils. Propagation of tea using stem cuttings is time-consuming witha low success rate, and does not exclude pathogens, so we aimed to develop in vitro methods to propagate tea. Shoot cuttings from five accessions, namely 'China Tea', 'Big Leaf, 'Assamica', 'Mississippi Small Leaf, and 'Georgia', were obtained from greenhouse-grown plants. They were surface-sterilized using sequential washes with 20% commercial bleach, 0.1% copper sulfate solution, 70% ethyl alcohol, and sterile water. The explants were then cultured in Murashige and Skoog agar medium supplemented withdifferent concentrations of rooting hormone IB A and incubated under fluorescent light (16 h light period). Most of the cultures had fungal growth, and fungi with characteristics typical of Phomopsis, Phyllosticta, Colletotrichum and Cladosporium were identified by culturing and microscopy. Few axenic cultures of 'Assamica', 'China Tea' and 'Georgia' were successfully obtained. These shoot cultures will be used for additional micropropagation and for crop-pathogen interaction studies in the future. Asan alternative to tissue culture, a hydroponic method with hydrogen peroxide was tested with limited success.