We measured allergen (Cry j 1) production, male flower weight, and male flower production (among young trees) in the five main Cryptomeria japonica cutting cultivars (Mio,Masuyama, Ryōwa, Kawadani, and Boka) in Toyama Prefecture in order to determine the cultivar most suitable for use in producing allergen extracts for C. japonica sublingual allergen immunotherapy. The results of the present study showed that Mio produced more pollen and Cry j 1, and its male flowers were larger than those of the other cultivars. Based on these results, Mio was determined to be the most suitable cultivar for use in producing allergen extracts. Furthermore, we used a paper bag-type vacuum cleaner to collect more pollen with greater ease, compared with the conventional method of branch-bagging.

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