Effect of various shapes of seed and initial germination percent on vigor and its relationship with seedling field emergence of hybrid maize (Zea mays L.,) single cross 704

In order to study on effect of hybrid maize single cross 704 having different primary germination percent various seed shapes on vigor and seedling field emergence, research was conducted at Seed and Plant Certification and Registration Institute (SPCRI) seed analysis laboratory and research field at Karaj in 2012. In laboratory, flat, medium and round having primary germination 88, 90, and 92 percent seeds vigor assessed by five vigor tests including radical emergence, electrical conductivity, cold, brick grit (Hiltner) and accelerated aging tests and germination percent after 66 and 144 h. in radicle emergence rate test, electrical conductivity and final germination and normal seedlings percent, seedling length and dry weight, seedling vigor length and weight Indices determined. In field seedling emergence percent and rate and cumulative rate and seedling length and weight vigor indices measured.  The results showed flat seed with 92 percent primary seed germination in comparison with other studied seed shapes and primary seed germination percent, had higher related to seed germination ability and vigor indices. In spite of which primary seed germination percent and various seed shapes effect on related to seedling field emergence indices was not significant, for the reason significant correlation of radical emergence percent after 144 h. in radicle emergence rate test and seedling field emergence percent and cumulative emergence rate, radicle emergence rate test could be effectively used for field seedling emergence and establishment.