Performance of liquid culture on in vitro mass multiplication of woolly aphid (Ceratovacuna anigera Zehntner) resistant sugarcane cultivar SNK-44.

Meristemculture culture on solid medium was the routine practice in micropropagation of most of the vegetatively propagated crops in vitro. Mass multiplication of sugarcane woolly aphid resistant cultivar SNK-44 with the help of meristem culture using liquid culture was the aim of present study. In the current experiment liquid medium was employed in all the stages of micropropagation in combination with different growth regulators for different stages. The meristem from 8 month old mother pant were inoculated on MS medium supplemented with 0.2 mg/l BAP + 0.1mg/l GA3 and 0.1mg/l NAA and 20 g/l sucrose for initiation. Shoots emerged from meristems were subcultured to multiplication medium consisting of MS + 0.2 mg/l BAP + 0.1mg/l NAA and 20 g/l sucrose. The culture bottles were kept with continuous shaking at five differ speeds viz., 25, 50, 75, 100 and 125 RPM on orbital shaker to determine the optimum speed for multiplication of large number of shoots in short period. The highest multiplication with an average of 6.45 seedlings per incoula on each cycle of multiplication was found at 100 RPM and lowest was at 25 RPM with 4.06 seedlings. The highest speed of 125 RPM did not increase the rate of multiplication rather it declined with an average of 4.83 seedlings per incoula per cycle. The meristems inoculated on static position responded poorly with an average of 2.29 seedlings per cycle of multiplication. The multiplied shoots were rooted in rooting medium (MS + 0.1 mg/l IBA and 20 g/l sucrose) and seedlings were hardened before discharge for field plantation. The rate of shoot multiplication was found increasing form 25 to 100 RPM but declined at 125 RPM revealing 100 RPM is the most suitable for large scale multiplication of sugarcane cultivars using liquid culture medium on orbital shaker. The cost of production for each seedling was also found less compared to gelled medium. The method was found most successful up to six to seven cycles. It is a novel way for popularizing the newly developed sugarcane cultivars in short time for larger areas.