Micropropagation of Colocasia esculenta (cv. Bolosso I)

Abstract

Taro (Colocasia esculenta (L.) is a perennial, aquatic and semi aquatic species, member of the family Araceae grown for its edible tuberous root. The application of conventional propagation techniques for Taro could not produce the high demand and quality planting materials due to its low productive capacity and diseases transmission. Therefore, this study was carried out to developed micropropagation protocol for Bolosso I typed cultivar of Taro using corm and sprout tip explants. MS media supplemented with different types and concentrations of plant regulators (BAP, kinetin, IAA, NAA and IBA) were used for initiation, shoot multiplication and root induction. A highly significant difference (P<0.0001) was observed between explant sources and among growth regulators for initiation, multiplication and root induction. Two percent NaOCl exposures for 15 and 20 minutes were found to be optimum for sterilization of sprout tip (83.33±0.85) and corm (66.63±0.51%) explants. Highest culture initiation was obtained on MS medium supplemented with 8 mg/l BAP (81.33±0.59), (76.67±0.48%) for corm and sprout explants, respectively. Maximum number of shoots (8.53±0.07/corm) and (5.8±0.39/sprout explant) was obtained on MS+8 mg/l BAP and 3mg/l IAA. The highest mean root number (6.9±0.09) and root length (11.25±0.5cm) per plantlet were recorded from MS media supplemented with 0.5mg/l IAA and 1.5mg/l IAA, respectively. Eighty percent survival efficiency was observed on the soil mix ratio of 1:2:2 (red: sand: coffee husk, respectively). This developed propagation protocol can be used to produce quality and true-to-type Taro planting material for large scale commercial production under natural condition.