Abstract
The author has made some experiments in which wheat varieties differing in cold resistance were compared in regard to the growth rates of the seedlings grown under different temperatures. The results of the experiments noted above are materially as follows: when frown in the green house or on the field during warmer seasons (autumn or spring), winter hardy varieties excel non-hardy ones in the growth rates or seedlings. On the contrary, when the plants are grown, in winter, either in the glass house (not heated) or on the field, the reverse is the case; namely the growth of winter hardy varieties goes more slowly than that of non-hardy ones. It may be questioned from the present study that the wellknown fact that, when grown in winter, winter hardy varieties are usually far richer in soluble sugars than non-hardy ones would be attributed to the fact that in the former the consumption of photosynthetic substances, say sugars, may be reduced on account of the slower growth at low temperature.
