Screening Camelia sinensis Germplasm Against Grey Leaf Blight of Tea

Abstract

Grey blight is a foliar disease of tea plants (Camellia sinensis) caused by Pestalotiopsis. The grey blight pathogen was isolated from infected leaves of tea plants in the National Tea and High Value Crop Research Institute (NTHRI), Shinkiari, Khyber Pakhtunkhwa, Pakistan. Eight different varieties, Indonesian, Roupi, Jue King, P-5, P-3, Qi man, Chuy and P-1, were investigated for yield loss and resistance against the grey blight disease. All varieties displayed considerably different levels of resistance to Pestalotiopsis (p<0.05). The most resistant variety was Indonesian, which showed the lowest number of lesions (1.5 leaf -1 ) and the smallest lesion diameter (3.0 cm), whereas the most susceptible variety was P-1 which showed the highest number of lesions (3.83 leaf -1 ) and the largest lesion diameter (15.0 cm).The grey leaf blight pathogen significantly affected biomass and dry matter of the tested varieties. Compared to non-inoculated control, inoculation with Pestalotiopsis reduced the number of leaves by 40% (p<0.05), fresh leaf weight by 31% (p<0.05) and dry leaf weight by 59% (p<0.05). Whereas, the Indonesian variety was the least affected showing only 11% (p<0.05), 19% (p<0.05), and 28% (p<0.05) reduction in number of leaves, fresh weight and dry weight, respectively, over control. These results showed that Pestalotiopsis significantly reduced tea yield and that this disease can be managed by growing resistant varieties.

Automated Detection of Selected Tea Leaf Diseases by Digital Image Processing Using Convolutional Neural Network (CNN): Bangladesh Perspective

“…Afterward, those samples were observed in laboratory by microbial culture media and microscopic analysis to compare causal pathogen to further ensure speci city of the predictions. For the rst sample, it was found that the leaf had been infected by Pestalotiopsis theae showing grey blight symptoms which is concordant with previous ndings [34]. Then the picture of the leaf was taken and checked by this proposed CNN model and the results of the model and laboratory test are similar.…”

In vitro Antagonism of Trichoderma Isolates and Efficacy of Chemical Fungicides against Mycelial Growth of Pestalotiopsis theae

“…On the other hand, experiment conducted by Kishor et al (2016) reported Trichoderma isolates' performance on effectively controlling this pathogen and concluded that integrated approach in pathogen management would be more fruitful if compatibility of BCA with fungicides were looked into. For long-term and environmentally friendly management of this disease, finding and deploying resistant varieties, specifically for organic tea production, is highly desirable (Akbar et al, 2017). Growers may be able to minimize infection by avoiding physical plant damage and by growing plants to avoid stress.…”

Chemical Composition of a Supercritical Fluid (Sfe-CO2) Extract from Baeckea frutescens L. Leaves and Its Bioactivity Against Two Pathogenic Fungi Isolated from the Tea Plant (Camellia sinensis (L.) O. Kuntze)

“…Pseudopestalotiopsis camelliae-sinensis was shown to cause grey blight disease on tea plants in China [ 13 ]. Some research has showed that planting disease-resistant varieties of C. sinensis has a certain effect on controlling the tea plant disease infected by Pestalotiopsis species [ 14 ]. In addition, the Colletotrichum species is also a common group of plant pathogens that are responsible for anthracnose diseases [ 15 , 16 ].…”