Transcriptome Analysis of an Anthracnose-Resistant Tea Plant Cultivar Reveals Genes Associated with Resistance to Colletotrichum camelliae

Abstract

Tea plant breeding is a topic of great economic importance. However, disease remains a major cause of yield and quality losses. In this study, an anthracnose-resistant cultivar, ZC108, was developed. An infection assay revealed different responses to Colletotrichum sp. infection between ZC108 and its parent cultivar LJ43. ZC108 had greater resistance than LJ43 to Colletotrichum camelliae. Additionally, ZC108 exhibited earlier sprouting in the spring, as well as different leaf shape and plant architecture. Microarray data revealed that the genes that are differentially expressed between LJ43 and ZC108 mapped to secondary metabolism-related pathways, including phenylpropanoid biosynthesis, phenylalanine metabolism, and flavonoid biosynthesis pathways. In addition, genes involved in plant hormone biosynthesis and signaling as well as plant-pathogen interaction pathways were also changed. Quantitative real-time PCR was used to examine the expression of 27 selected genes in infected and uninfected tea plant leaves. Genes encoding a MADS-box transcription factor, NBS-LRR disease-resistance protein, and phenylpropanoid metabolism pathway components (CAD, CCR, POD, beta-glucosidase, ALDH and PAL) were among those differentially expressed in ZC108.

Development of a DNA-based real-time PCR assay for the quantification of Colletotrichum camelliae growth in tea (Camellia sinensis)

“…As shown in Fig. 2b, lesions developed on leaves inoculated with CCA spores and their diameters were large at 4 DPI, while the un-inoculated control leaves did not show any lesion development, confirming that LJ43 was susceptible to C. camelliae CCA, as previously reported [10]. The same results were observed by analysing the pathogen growth with qRT-PCR ( Fig.…”

“…The tea cultivar Longjing 43 (LJ43) was observed to be susceptible to C. camelliae in the tea garden ( Fig. 2a) [10]. In this study, C. camelliae CCA growth was first quantified on the tea cultivar LJ43.…”

“…Colletotrichum camelliae and C. fructicola were the species most often isolated and were proposed as dominant pathogens of tea [20][21][22][23]. Colletotrichum camelliae damages tea leaves and causes several tea diseases known as tea leaf blight, tea brown blight, or tea anthracnose [10,[21][22][23][24]. The fungus C. fructicola is both a pathogen and an endophyte of several plant species, while C. camelliae was only isolated as a pathogen of Ca.…”

“…Two tea plant cultivars, LJ43 and Zhongcha 108 (ZC108), were used. Previous research reported that ZC108 was resistant to C. camelliae [10]. In this study, leaves of both LJ43 and ZC108 were droplet-inoculated with the C. camelliae isolate CCA.…”

“…Tea is a perennial, evergreen woody plant, and some plants have lived for more than a thousand years. During its long life, tea faces many biotic and abiotic stresses, including pathogens, insects, low and high temperatures, and heavy metals [4][5][6][7][8][9][10][11][12]. Therefore, tea can be used as a perennial, medicinal species to characterize how defence responses are activated or suppressed.…”