ENHANCED GERMINATION RATES AND GROWTH OF DCPTA-TREATED GUAYULE SEED

A 26-mu-M DCPTA seed treatment for guayule (Parthenium argentatum Gray) was developed. We obtained a 23% increase in germination rate as measured by the coefficient of velocity (C.V.). Greenhouse seedlings grown from DCPTA-treated seeds exhibited a 22% increase in dry weight and a 95% increase in survival rate under water-limiting conditions. In field-grown guayule, multiple foliar applications of 8.2 mM DCPTA increased the total amount of rubber in roots as much as 58% without affecting the rubber content in the stems. Chemical name used: 2-Diethylaminoethyl-3,4-Dichlorophenylether (DCPTA).