XVI International Botanical Congess

Glucosinolates (GSLs), N- and S-containing thiogluco-sides characteristic of the Capparales, hydrolyze to toxic products such as isothiocyanates and nitriles. I postulated that GSLs might be involved in the ability of selected cultivars of Sinapis alba L. to inhibit reproduction of the nematode Heterodera schachtii Schm. (HS). Upon hatching of cysts, HS juveniles enter and reproduce in roots of suitable hosts. In experiments with cultivars that allow or inhibit HS reproduction, I determined GSL composition of S. alba through develop- ment, examined the effect of nematode infestation, and manipulated environmental factors to alter root GSL composition. Quantitative composition differed among cultivars, but was not linked conclusively to inhibition of HS reproduction.