Abstract

Micro propagation is an efficient technique used for seed development of sugarcane. Protocol for the rapid propagation of Co 05011, a newly released variety, was optimized in the present study with a view to find out the best explanting season and source for obtaining optimum morphogenetic responses. Shoot tip explants were collected at monthly interval on 20th of each month from the field grown crops of sugarcane variety Co 05011 and inoculated on MS medium. The highest frequency of establishment (75%) of explants inoculated in the month of March was recorded followed by October, February, September, April and November as compared to those explanted in other months. Explants inoculated in the months of March to November required a minimum period of about 40 to 45 days for establishment of shoot cultures, whereas those inoculated in the months of December and January which required 60 to 70 days to complete the establishment. In an another set of experiment, shoot tip explants were collected from different sources e. g. spring planted, autumn planted and ratoon of spring planted crop. Results revealed that explants collected from spring planted crop gave the best responses regarding frequency of shoot initiation (85%), establishment of shoot cultures (65%), number of shoots/culture (24.3) and rooting responses (86.7%) followed by those collected from autumn planted crop and ratoon of spring planted crop. These results indicated a remarkable effect of season of explanting and source of explants on various in vitro morphogenetic responses. The aforesaid results suggested that the season of explanting and source of explant were important factors which should be taken into consideration during micropropagation of sugarcane varieties.