Alterations in RAPD profiles of proliferating shootlets of sugarcane in response to thidiazuron

Abstract

207-210Proliferating shootlets of sugarcane varieties CoH 92 and Co 7717, raised from apical meristems, were cultured in vitro for 24 d in MS medium with different concentration of TDZ. DNA from leaves of these shootlets was extracted and amplified using 10 random decamer primers. A total of 50 RAPD products in var. CoH 92 and 43 in var. Co 7717 were formed. TDZ caused considerable differences in amplification products of both varieties. Several RAPD products, which were absent in control plantlets, amplified in TDZ treatments, such as 950 bp (CoH 92 and Co 7717) against primer 5´-AATCGGGCTG-3´ (10A04); 1200 bp (Co 7717) against primer 5´-AGCCAGCGAA-3´ (50A16); 1150 and 1000 bp (CoH 92 and Co 7717) and 900 bp (Co 7717) against primer 5´-CTGCTGGGAC-3´ (80B10); 950 bp (CoH-92) and 500 bp (Co 7717) against primer 5´-GTAGACCCGT-3´ (90B11); and 500 bp (CoH 92) against primer 5´-CCGCATCTAC-3´ (100C04). On the other hand, certain RAPD products, such as 220 bp (CoH 92) against primer 5´-TCGGCGATAG-3´ (40A10); 950 bp (Co 7717) against primer 50A16; 550, 360 and 320 bp (CoH 92) against primer 5´-GGACTGGAGT-3´ (60B04); and 1050 bp (CoH 92) against primer 80B10, amplified in the control plantlets disappeared due to TDZ treatments. Such altered RAPD profile in response to TDZ is an entirely new and hitherto unsuspected observation, which suggests a possible genetic change or perhaps to a synthesis of protein or non-protein regulators that affect the process of DNA synthesis/amplification