A grant of drought avoidance and efficient water use because of dwarfing genes utilization

Tall and dwarf isogenic lines of sorghum (Plainsman tall type and Plainsman short type), soybean (Hyuga and Hyuga dwarf line), and rice (Ginbozu and T angin) were grown by using 15 L containers to compare the relationships bet ween consumptive use (CU) and dry matter increase (DeltaW) and the yield be tween them. The linear relationships were found between CU and DeltaW. CU a t DeltaW = 0 was nearly equal to evaporation (E-s), except for two soybean strains. Transpiration efficiency (DeltaW/[CU-E-s]) did not differ signific antly between tall and dwarf isogenic lines. Hyuga consumed the largest amo unt of water because it had large DeltaW and low transpiration efficiency ( TE) and larger CU at DeltaW = 0. Two sorghum strains did not differ in CU f rom Ginbozu and Tangin because of their larger DeltaW, respectively, though they had the highest TE. Dwarf lines were always smaller in CU than tall l ines were in all the examined crops. Furthermore, they were inferior to tal l lines in the absolute yield, but they tended to be less in CU to achieve the same yield. These characteristics of dwarf lines will be useful in both viewpoints of the avoidance of drought injury and the efficient use of wat er.