Cold-water resistance of the remarkable rice varieties and lines in the Tohoku-Region. : (1) On the relation between cold-water resistance and morphological characters in rice plant.

[摘要] 1. The author inspected the cold water resistance of the remarkable rice varieties and lines in the Tohoku-district by flowing cold water irrigation in their principal growth period. 2. Varietal dfferences in the injury caused by the cold water cultivation in paddy field are very obvious. 3. Sterility percentages are fit to indicate the cold water resistability, as Dr. Y. KONDO insisted in his report. From result of my study, it appears that: (1) The cold water resistabilities of glutinous varieties are obviously higher than the non-glutinous ones. (2) Varieties, awned or carrying pigment with their cod, respectively are generally more resistant in comparison with reverse characteristic ones. (3) Moreover, the result indicates that high resistant varieties are more recognized in heavy-ear possessing and early maturing ones than much-sprouting and late maturing ones. 4. But I revealed that it was not difficult to rear cold water high resistant varieties which were non-glutinous, awnless and non-pigment in their cods by means of hybridization.

[学科分类] 农业科学（综合）