Oak mushroom is one of the most important non-timber forest products at the forest sector in Korea. In recent years, the Korean farmers have suffered from the import increase of saw bed medium from Chinese and the price decrease of the oak mushroom. In order to overcome this phase, it is important to develop good varieties that can compete with Chinese varieties. National Institute of Forest Science is studying to develop excellent varieties through the Golded Seed Project. We report some of the results as part of that. The strains of oak mushroom were made through mono-mono cross method using domestic distribution varieties. Sawdust cultivation was carried out on 100 - day cultivation and 3 - stage mushroom yield using 2 kg hexahedron culture medium. Of these, 60 strains were used for sawdust cultivation, and 3431 strain (23%) was selected when the yield was 20% or more of the weight of the medium. Four strains (3396, 3414, 3419, 3430) were selected when the mushroom yield was 15% to 20% of the weight of the medium. 3404 strain with excellent mushroom shape was selected, though the yield was low (10%). Generally, mushroom yield was the highest in the first stage, and the number of mushrooms in the second stage was decreased rapidly. Also, 10 strains did not produce mushroom in this study. The 3431 strain occurred mushroom production with 87% yields in the first stage and did not occur in the third stage. The 3404 strain with excellent mushroom shape occurred in primary and tertiary. The average weight of mushrooms was 13 g and 54g, respectively. The strains (3431, 3404) will be used for the selection of varieties through cultivation test in the future.

Lentinula edodes is a very important edible mushroom and is widely cultivated in Asian countries using a large number of varieties. National Institute of Forest Science (NIFoS) conducts Golden Seed Project to develop new shiitake varieties and we examined cultural characteristics of seven candidate strains compared to three existing cultivars. As a result, optimal growth temperature and mycelial growth on potato dextrose agar (PDA) for seven days at the optimal temperature were 27°C, 55 mm in Sanbaekhyang, 27°C, 50 mm in Sanjo701ho, and 25°C, 49 mm in Sanjo707ho, respectively. Five of the candidate strains except NIFoS 3309 and 3310 showed the highest growth at 25°C. Mycelial growth of NIFoS 2889 and 2905 showed the fastest (60 mm) and the slowest (32 mm), respectively. Six strains showed bulging on surface of media in sawdust bag cultivation for 30 days. In particular, the cultiver, Sanjo701ho had heavy bulging. Four strains (NIFoS 624, 971, 3310, and 3363) did not show bulging and NIFoS 971 grew slower than the others. Keywords : Browning, Characteristics, Lentinula edodes, Mycelial growth, Tunicate

Sawdust bag cultivation was performed to understand the effect of different sawdust substrate (Quercus mongolica, Q. acutissima, Q. serrata, Q. aliena, and Q. variabilis) on the eight variety of shiitake (Poongnyunko, SANJO 701, Mori 436ho, Sanlim 10ho, Chilha 6ho, Yoogiro, Baekwhahyang, Charmaram). After inoculation, sawdust substrate block (2 kg) was cultivated at 22°C for 120 days. During the production period, the temperature was adjusted to 18°C and the relative humidity at 90%. The yield was calculated based on the fruit bodies from the first, second and third flush. As results, Poongnyunko yielded 455 g on the substrate, Q. serrata, 378 g on Q. aliena, and 333 g on Q. variabilis. Chilha 6ho yielded 304 g on Q. mongolica and Charmaram yielded 245 g on Q. acutissima. The average weight of mushrooms from Charmaram was 40-45 g on all five substrates and Q. variabilis was the best among them. In terms of phenotypic characteristics, Chilha 6ho was generally better than the others. Charmaram, Poongnyunko, Sanlim 10ho also had good characteristics. Mori 436ho, Yoogiro, Baekwhahyang developed for log cultivation showed lower yield compared to the varieties for sawdust bag cultivation. Keywords : Lentinula edodes (Shiitake), Querqus spp., Saw-dust bag culture, Yield