Methods of evaluating seed quality of some Atriplex species.

摘要

Atriplex is an important shrub of the world's desert regions and provides high quality forage for wild and domestic animals. A high level of dormancy, which may result in inaccurate assessment of seed viability, characterizes Atriplex species. The objective of this study was to determine the accuracy of tetrazolium tests (TZ) for estimating seed viability of shadscale (Atriplex confertifolia (Torr. & Frem.)), Gardner saltbush (Atriplex gardneri (mog.) D. Dietr), fourwing saltbush (Atriplex canescens (Pursh) Nutt.), Mediterranean saltbush (Atriplex halimus L.) and to develop germination procedures for these species.;Seeds of each species were imbibed in water for 24 hours, then cut longitudinally to expose the embryo, and placed in 0.1% TZ solution for 3, 5, 7, 10 and 24 hours. Seven to ten hours was sufficient time for seed staining. The effects of washing and prechilling treatments on TZ staining processes were also evaluated. Unlike shadscale, Mediterranean saltbush and Gardner saltbush showed significant differences on the normal staining percentage with the prechilling treatment. Washing was the most effective treatment for promoting staining of fourwing saltbush.;Scarification, washing, prechilling, and a combination of treatments were evaluated for overcoming seed dormancy and promoting seed germination of shadscale and Gardner saltbush. These treatments consisted of four minutes of seed scarification at 32 RPM in a hand operated Forsberg scarifier, exposing seeds to running tap water (21;Optimum temperature for germination was determined by using germination temperatures of 10, 15, 20, 5-15, 15-25, and 20-30