Characteristics and effectiveness of glasshouse miniature seed orchards in Cryptomeria japonica D. Don

Abstract

We produced seeds of Cryptomeria japonica trees in a glasshouse miniature seed orchard to prevent pollen contamination. In the glasshouse, male flowers shed pollen from February 4 to March 27, 2002, whereas female flowers were open from February 5 to March 22, 2002. Outdoors, pollen of Cryptomeria japonica was dispersed from February 21 to April 6, 2002. Flowering in the glasshouse was approximately three weeks earlier/Peak flowering of male flowers was from February 17 to March 13 and that of female flowers was from February 15 to March 3, 2002 in the glasshouse. The peaks of flowering of male flowers and female flowers overlapped. The germination frequency of seeds produced in the glasshouse was almost the same as that of seeds produced in outdoor seed orchards. We conclude that a glasshouse miniature seed orchard is effective in preventing pollen contamination.