Five different material wheat(synthesis hexaploid,rare species,farmyard variety,recommended variety,drought-resistant variety) were researched in this article,and the main element analyses of draught tolerance exponential of drought-resistance physiological index of different wheat(the maximum water content 20% in the soil) when severe drought were made.It showed that different drought-resistant indexes were differ-ent in effect to different wheat varieties.The index of synthesis hexaploid wheat was proline...