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Jojoba [Simmondsia chinensis (Link) C.K. Schneid.] is a new oil (wax) seed crop for arid and semiarid environments where salinity is frequently a major problem. The objectives of this work were to study the effects of salinity on germination and mobilization of reserves in jojoba seed. Salt concentrations (NaCl:CaCl2 1:1, w/w) having electrical conductivities (EC) of 0, 5, 10, and 15 dS/m significantly reduced germination, fresh weight of seedlings, and the amount of lipid used in ‘Vista’ jojoba. Germination was reduced from 82.6% in nonsaline conditions to 42.6%, fresh weight was reduced from 314 to 98 mg, and the amount of lipid used was reduced from 136 to 83 mg in strong (EC = 15.0 dS/m) saline treatments. Higher levels of salinity also resulted in accumulation of total soluble sugars, delayed initiation of germination and lipid breakdown, and decreased C38 and C40 esters with an increase in C42. These data suggest jojoba is not salt‐tolerant during germination.

Guayule (Parthenium argentatum Gray), a xerophytic shrub native to northeastern Mexico and southern Texas, is receiving renewed attention as a potential source of natural rubber in the semiarid regions of the world. A major problem in propagating guayule is seed dormancy. The objectives of this investigation were to evaluate and modify old seed treatment methods and to develop an improved standard procedure for quick and complete germination of guayule seeds to enhance breeding and improvement of the crop. The optimum concentration of sodium hypochlorite (NaOCl) needed for breaking seed dormancy was higher for younger than older seeds. Seeds should be washed and soaked in distilled water for 8 hours followed by a 2‐hour treatment with a solution of equal parts of gibberellic acid (200 ppm) and NaOCl (1.0% for fresh seeds, and 0.25% for 1‐year‐old seeds). With this procedure freshly harvested seeds germinated 100% under light and over 70% in complete darkness. Emergence of seedlings from soil depended primarily upon seed size. Large guayule seeds emerged better at all depths to 18 mm after standard treatment than did medium or small seeds.

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