Effects of auxins and thiamine on the efficacy of techniques of clonal propagation in Jatropha curcas L.

Effect of auxins (IAA, IBA, NAA) and vitamin-B1 (thiamine) on rooting response of branch cuttings and air-layers of Jatropha curcas in relation to spring and monsoon seasons was investigated. Spring season was found best for clonal multiplication of genetically superior material in jatropha. Cuttings treated with 600 and 800 mg L−1 thiamine showed 100% sprouting in both seasons. The average sprout growth was also found maximum in thiamine treated cuttings. Auxins enhanced rooting of cuttings in spring season but showed very poor response or even failed to root during monsoon. Among different growth regulators; thiamine triggered highest rooting during monsoon and was comparable during spring season. Average percent rooting was also recorded maximum in air-layers treated with thiamine (75, 150, 300, 600 mg L−1) in comparison to auxins in both the seasons. However, number of roots per layer increased with increasing concentration of NAA and IBA in spring but decreased in monsoon season. Cleft grafting was found more promising in terms of success in rainy season however; the growth of the grafted plants was quite slow as compared to spring season. This technique can be practically applied on commercial scale in the areas where Jatropha gossypifolia grows as weed.