Thermoperiodity and flower formation in some tomato varieties

Abstract

Twelve tomato varieties were exposed to night temperatures of 50—55° F and 65—70° F for two weeks just after cotyledon expansion beginning one week after the seed was sown. The responses of each variety were observed as regards the days to the first open flower, the number of leaves formed before the first inflorescence, and the number of flowers in the first and second inflorescence. A night temperature of 50—55° F increased the number of days to the first open flower, and decreased the number of leaves. The number of flowers in the first inflorescence was increased in all varieties except. J. Moran and Pearson by night temperatures of 50—55° F.