Morphology Characterization, Molecular Identification, and Pathogenicity of Fungal Pathogen Causing Kaffir Lime Leaf Blight in Northern Thailand

Abstract

Thailand is known to be the largest producer of kaffir lime leaf products in the global market. In 2021, leaf blight was found on kaffir lime plants (Citrus hystrix DC.) in Lamphun Province of northern Thailand. This disease has been associated with significant economic losses. However, there have been no prior reports of leaf blight on kaffir lime plants in Thailand or anywhere else in the world. In this study, causal fungi were isolated from lesions of kaffir lime plants and a total of three fungal isolates were obtained. All causal fungi were identified as Lasiodiplodia chinensis based on morphological characteristics and the phylogenetic analysis of combined sequences of the internal transcribed spacer (ITS) of ribosomal DNA, the translation elongation factor 1-alpha (tef-1), β-tubulin (tub), and RNA polymerase II subunit (rbp2) genes. Pathogenicity tests were conducted and the results revealed that all isolated fungi caused symptoms of leaf blight on inoculated leaves. This outcome was similar to symptoms that naturally occur and have been observed in the field. This is the first report on kaffir lime leaf blight caused by L. chinensis. Our study will provide information of high value for the development of effective strategies for the monitoring and prevention of this disease.

Internet of things system for lime planting in Maha Sarakham community

“…When the lime is one year old, the fertilizer with formula 15-15-15 about 300 grams should be applied to each tree, and for two years old lime, agriculturists should increase the amount of fertilizer by applying it two times a year, about 1 kg each time [20]. In this province, lime growers have always faced problems from the process of preparing the planting site and selecting lime varieties to lime diseases [26] such as canker causing root rot, fruit loss due to acidic soil and insufficient water, and too much productivity of lime in the season resulting in selling limes at a low price. Farmers must have a proper method to select suitable planting areas and soil analysis in the planting fields.…”

Molecular identification and phylogenetic analysis of Alternaria perpunctulata GVKNSV7 causing leaf spot disease on Alternanthera philoxeroides (Mart.) Griseb : A first report in India

“…Following the 7-15 days incubation interval, a meticulous examination of the Petri dishes ensued, focusing on any discernible growth of fungal colonies originating from the symptomatic leaf tissues (Gera et al, 2023 andSuwannarach et al, 2022). Colonies were subjected to scrutiny regarding aspects such as color, texture, and other morphological attributes.…”

Morphology, Molecular Identification, and Pathogenicity of Two Novel Fusarium Species Associated with Postharvest Fruit Rot of Cucurbits in Northern Thailand

“…Therefore, plantation areas dedicated to the cultivation of both watermelon and other melon plants have increased significantly. Conversely, the prevalence and severity of some fungal-based diseases have also increased when plants have been grown in sub-optimal locations [4,27,28]. In Thailand, the major areas for watermelon and melon cultivation are located in the northern region of the country, including Chiang Mai, Kamphaeng Phet, Phayao, Phichit, Phitsanulok, and Sukhothai Provinces.…”