Earticle

Lecanicillium fungicola is the causative agent of dry bubble disease in commercially cultivated mushrooms, primarily affecting Agaricus bisporus, Agaricus bitorquis, and Pleurotus ostreatus. The symptomatology ranges from minor necrotic lesions on the pileus to severe structural deformities, such as stipe blow-out or the formation of undifferentiated tissue masses known as dry bubbles. Regarding its economic impact, this pathogen is highly devastating, resulting in estimated annual losses of 2-4% of total revenue for the mushroom industry. Disease management necessitates rigorous hygiene protocols and the strategic application of fungicides. However, chemical control remains challenging due to the fungicide sensitivity of the host mushrooms.

The new brown cultivar, Agaricus bisporus ’Okhyang’, was developed by the Chungcheongnam-do Agricultural Research and Extension Services with the goal of generating a cultivar suited to the domestic cultivation environment and superior to previously developed cultivars. The ‘Okhyang’ cultivar was selected through basidiospore crossbreeding between ‘CM021735’ and ‘CM021812’, exhibiting faster mycelial growth (58 mm) and darker cap color than the reference cultivar ‘Dahyang’ (53 mm) after 15 days at 25 oC. Furthermore, the cultivar may have an advantage in distribution owing to its more uniform cap shape and firmer fruiting body. Individual fruiting body weight and yield were 41.8 g and 11.2 kg/m2, respectively, which were approximately 9.8% higher than those of ‘Dahyang’. Therefore, ‘Okhyang’ cultivar can potentially increase income for button mushroom farmers and enhance consumer preference.

This study assessed the safety of commercially available Cordyceps militaris in Korea by analyzing seven heavy metals, 321 pesticide residues, and three radionuclides in ten domestic and imported samples. Cadmium was not detected in any sample, and all other heavy metals were detected at trace levels within safe limits. Two pesticide residues, metalaxyl and carbendazim, were detected in one sample imported from China, both below the MRLs established for other mushroom species in Korea. Radioactivity was not detected in any sample, although concentrations in samples from China tended to be higher than those in domestic samples. Overall, all contaminants were within safe limits; however, given the absence of Cordyceps militarisspecific regulatory standards in Korea, the establishment of crop-specific MRLs and systematic safety management throughout the cultivation-to-distribution chain are warranted.

A new high-temperature Oak mushroom (Lentinula edodes) variety, ‘Heunghwa 2ho’, adaptable to climate change, was developed for bed-log cultivation. Plant variety protection was applied for in 2022, and the variety is currently distributed to farms through non-exclusive licensing. The optimum mycelial growth temperature was 25oC, and the growth rate of 16.2±0.2 mm/7days was superior to that of the control cultivar. Fruiting body formation occurred at 18~28.1oC. The pileus was flat and thinner (9.6±2.9 mm) than that of the control cultivar. Fruiting occurred in spring, late summer, and autumn in concentrated or scattered patterns, with a dry weight of 22.5 kg/m3. Three years fresh yield reached 100 kg/m3, exceeding the yield criterion for economic viability in high-temperature varieties, and the second-year production rate of 80.9% further demonstrated its commercial potential.