No abstract

Key words: ge netic vari abil ity, lignothioglycolic acid, pro tein-free lignin, soy bean cultivars Ab stractMe chan i cal dam age is one of the causes of great loss in the qual ity of soy bean seeds dur ing har vest and pro cess ing. Consid er able in ter est ex ists in the lignin since its de po si tion in the seed coat tis sue pro vides me chan i cal re sis tance and pro tects the cell against mi cro or gan isms. In ad di tion, peroxidases might be in volved in the ox i da tion of cinnamyl al co hols prior to their poly mer iza tion dur ing lignin for ma tion. Thus, the aim of the pres ent work was to an a lyze the lignin con tents and peroxidases ac tiv i ties of six Bra zil ian soy bean cultivars (Savana, Paranagoiana, FT-10, Santa Rosa, Doko and Paraná) and their re la tion ships with the me chan i cal dam age. Re sults showed that the lignin con tent and peroxidase ac tiv ity in the seed coat sig nif i cantly dif fered among the soy bean cultivars. Cultivars Doko and Paraná had the high est con tents of lignin and peroxidases ac tiv i ties while the other cultivars had low est lignin con tents and en zyme ac tiv i ties. Lignin con tent and peroxidase ac tiv ity may be rea son able in di ca tors of re sis tance to me chan i cal dam age in soy bean seeds.