Enhanced resistance to blister blight in transgenic tea (Camellia sinensis [L.] O. Kuntze) by overexpression of class I chitinase gene from potato (Solanum tuberosum)

Abstract

Tea is the second most consumed beverage in the world. A crop loss of up to 43 % has been reported due to blister blight disease of tea caused by a fungus, Exobasidium vexans. Thus, it directly affects the tea industry qualitatively and quantitatively. Solanum tuberosum class I chitinase gene (AF153195) is a plant pathogenesis-related gene. It was introduced into tea genome via Agrobacterium-mediated transformation with hygromycin phosphotransferase (hpt) gene conferring hygromycin resistance as plant selectable marker. A total of 41 hygromycin resistant plantlets were obtained, and PCR analysis established 12 plantlets confirming about the stable integration of transgene in the plant genome. Real-time PCR detected transgene expression in four transgenic plantlets (T28, C57, C9, and T31). Resistance to biotrophic fungal pathogen, E. vexans, was tested by detached leaf infection assay of greenhouse acclimated plantlets. An inhibitory activity against the fungal pathogen was evident from the detached leaves from the transformants compared with the control. Fungal lesion formed on control plantlet whereas the transgenic plantlets showed resistance to inoculated fungal pathogen by the formation of hypersensitivity reaction area. This result suggests that constitutive expression of the potato class I chitinase gene can be exploited to improve resistance to fungal pathogen, E. vexans, in economical perennial plantation crop like tea.

Improved antifungal activity of barley derived chitinase I gene that overexpress a 32 kDa recombinant chitinase in Escherichia coli host

“…31 The chitinase I gene is evolutionarily conserved and is present in both monocot and dicot plants such as cocoa, 32 potato 33 and rice. 34 The chitinase I gene also has a chitin binding domain, which is absent in class II chitinase and hence make it superior in antifungal potential.…”

Simultaneous induction of jasmonic acid and disease-responsive genes signifies tolerance of American elm to Dutch elm disease

“…4 ). Most of these genes have shown antifungal activity in vitro and enhanced resistance to pathogenic fungi when constitutively overexpressed in planta 35 36 37 38 39 40 41 42 . The induction of most of these genes at 96 hpi in the tolerant genotype, along with their demonstrated antifungal activity is in agreement with the SEM observations, where no hyphal growth was detected in ‘Valley Forge’ along the experimental period.…”

Chitinases—Potential Candidates for Enhanced Plant Resistance towards Fungal Pathogens

“…Nowadays, chitinase genes have been cloned and expressed into various plant species, resulting in improved disease resistance in the developed transgenic plants [74,75]. A class I chitinase gene (AF153195) from potato was introduced into the tea genome and its overexpression resulted in an enhanced resistance against blister blight disease [76]. Zarinpanjeh et al [77] reported improved resistance against Sclerotinia stem rot in Brassica napus by the co-expression of defensin and the chimeric chitinase gene.…”