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Since 1999, severe losses have been observed on seedlings of muskmelon (Cucumis melo) in four commercial fields in the Doddaballapura, Nanjangud, Malvalli and Arasikere regions of Karnataka, India. Losses occurred during the months of October and November. Disease symptoms included stem necrosis with an exudation of gummy material, angular water-soaked lesions on the leaves and rotten fruits. The presence of black pycnidia was observed on the stems, leaves and fruits. A fungus was isolated from diseased stems, leaves and seeds, by plating surface-sterilized plant tissues onto potato dextrose agar (PDA) medium. On PDA, the mycelium was olivaceous green and few pycnidia were observed. White aerial mycelium was also produced. Conidia were hyaline, cylindrical with rounded ends, mostly nonseptate, but a few single-septate, and 6 -11 × 3 -5 µm in size. Based on the symptoms and the morphological characteristics, the fungus was identified as Didymella bryoniae (Keinath et al., 1995). The pathogen causes gummy stem blight of cucurbits on species of Citrullus, Cucumis and Cucurbita (Keinath et al. 1995). To confirm pathogenicity of D. bryoniae, 30-day-old muskmelon plants were wounded using a syringe needle and inoculated at the collar region with a suspension of 12 × 10 5 conidia mL −1 in sterile distilled water. The plants were covered with plastic bags for 2 days and kept at 23°C and 90% relative humidity, with a 12 h photoperiod. Plants were assessed 7 days after infection. Inoculated plants produced typical symptoms on stems, leaves and fruits.The fungus was consistently re-isolated from infected plant parts. In contrast, the control plants did not show symptoms.The seedborne nature of D. bryoniae was evaluated by plating different components of the seed, such as the seed coat, cotyledons and embryo, using the Standard Blotter method (ISTA, 1999) and PDA. Results clearly indicated that all parts of the seed were infected with the D. bryoniae. Subsequently, infected seeds were sown in the field and 41% incidence of disease was recorded. Didymella bryoniae was re-isolated from the harvested seeds. Although the disease was previously noticed on fruits of Citrullus vulgaris var. fistulosus and on leaves of Sechium edule and Praecitrullus fistulosus in India (Sohi & Om-Prakash, 1972), this is the first confirmed report of the pathogen on C. melo in this country. The disease incidence has increased from 13% in 1999 to 21% in 2003. Consequently, disease monitoring and management measures need to be taken.

Cyprinid herpesvirus 2 (CyHV-2) is the etiological agent of herpesviral hematopoietic necrosis disease (HVHND), which causes severe mortality in ornamental goldfish (Carassius auratus), crucian carp (Carassius auratus), and gibel/prussian carp (Carassius gibelio). Quick and hassle-free point-of-care detection of CyHV-2 is vital for the maintenance of ornamental fish health. In this manuscript, we describe the development of a rapid and sensitive RPA (recombinase polymerase amplification) assay, coupled with lateral flow dipsticks (LFD), that can achieve sensitive diagnosis of CyHV-2 in goldfish within 20 min at 36 °C with the satisfactory detection limit of 10 2 gene copies per reaction. This is the first report wherein major capsid protein (MCP) of CyHV-2 was targeted for RPA-LFD assay development. The assay did not show any cross-reactivity with other viral pathogens like cyprinid herpesvirus 3 (CyHV-3), spring viremia of carp virus (SVCV), infectious spleen and kidney necrosis virus (ISKNV), and viral nervous necrosis virus (VNNV). Furthermore, screening of CyHV-2 infection in CyHV-2-infected goldfish did not yield any false positive/negative results. In short, the RPA-LFD assay developed in this study presents a simple, rapid, and sensitive method for point-of-care diagnosis of CyHV-2, especially under resource-limited conditions.