Abstract: | Seed of the Swedish lucerne variety U 0615 harvested in a seed field in Israel for four consecutive seasons was tested in field trials in Sweden. Differences in seed yield between plants were demonstrated in Israel — less winter-dormant plants gave more than four times as much seed as winter-dormant plants. On the average Israel-grown seed yielded less in the first cut than Swedish-grown seed, which indicates a decrease in winter-hardiness. The yield was especially reduced in 1962 when winter damage was severe. It is pointed out that varieties may react differently when seed is produced outside the area of adaptation. In a variety with a high degree of heterogeneity, e.g. U 0615, the mode of increase and the stage to be multiplied at southern latitudes should be tested carefully before it is undertaken commercially.Swedish Seed Association, Uppsala 1, Sweden.The Hebrew University, Faculty of Agriculture, Rehovot, Israel. |