Effect of Cold Stratification on Seed Germination of Four Species of Amaranth

Germination responses of four species seed of Amaranth,Slender Amaranth,Emarginate Amaranth and Redroot Amaranth,Tumble Weed from Xuzhou were examined in 15℃,20℃,25℃,30℃,20℃/25℃respectively.The results showed that the preferential temperature of seed germination for Slender Amaranth and Tumble Weed was around 25℃,for Emarginate Amaranth and Redroot Amaranth were around 30℃;Alternating temperature had no significant effect on the seed germination of four species of Amaranth. Germination rate of Emarginate Amaranth was significantly increased under dark,but no significant changes on the other three species.After low-temperature storage for 4 years,the germination rate,germination energy and germination index of Slender Amaranth and Tumble Weed were reduced significantly,while those of Emarginate Amaranth and Redroot Amaranth were increased significantly.