MONITORING THE OUTPUT OF A HYBRID LARCH SEED ORCHARD USING ISOZYME MARKERS

A method was developed for estimating the frequency of hybrids in the seed crop of a multiclonal hybrid larch seed orchard using isozyme gen etic markers. The technique was used to monitor the output of a commer cial hybrid larch seed orchard. Among the seeds collected from Europea n larch clones, some 65 per cent were hybrid, compared with 19 per cen t from Japanese larch clones. Unequal reproductive effort and differen ces in flowering time between the two parental species may account for the results. Possible application of these techniques for the certifi cation of seed and planting stock are discussed.