THE EFFECTS OF SILVER-NITRATE, COLCHICINE, CUPRIC SULFATE AND GENOTYPE ON THE PRODUCTION OF EMBRYOIDS FROM ANTHERS OF TETRAPLOID WHEAT (TRITICUM-TURGIDUM)

Anther culture of four tetraploid wheat (Triticum turgidum) genotypes was studied using ten different culture medium treatments in a randomi zed block design with four replicates. Each replicate consisted of 2 p ots with 3 plants. Anther donor plants were grown in a greenhouse with a 16 h day/8 h night at 25 degrees C and 15 degrees C, respectively. The first treatment which was considered as the control, was potato 2 medium modified by adding 0.5 g l(-1) glutamine and solidified by gelr ite (4 g l(-1)). The nine test treatments differed from the control by addition of 3 different concentrations of silver nitrate (1, 2.5 and 5 mg l(-1)), colchicine (10, 100 and 200 mg l(-1)) or cupric sulfate ( 2, 5 and 10 mg l(-1)). The study of about 2000 anthers per genotype an d treatment showed that both genotype and treatment affected embryoid formation. The presence of cupric sulfate (10 mg l(-1)) and silver nit rate (2.5 and 5 mg l(-1)) usually increased the frequency of embryoid formation in 3 genotypes out of the 4 studied. On the contrary, colchi cine had a significant and negative effect on anther culture responses for three out of the four genotypes studied. Because of the large gen otype x medium interaction, it is very difficult to identify the best medium for embryo production by all genotypes studied.