Standardization of grafting technique in Kusum [Schleichera oleosa (Lour.) Oken

Abstract

The species, Schleichera oleosa (Kusum), holds an important place in the livelihood of tribal farmers in eastern region of India. It is getting popular due to its ethnobotanical values and its potential use as host plant for lac production. Its natural population and genetic variability is declining at faster rate due to deforestation and human interventions. Mass production of Kusum seedlings is a major challenge and moreover, auto-generation of heterozygous nature in plants calls for long term experiments for its genetic improvement which require huge monetary investments. Moreover, the factors like low quality and quantity planting materials and the problem of restricted growth in plants raised from seeds hinder the interest of the farmers. Hence, clonal propagation through grafting could be an option. The scientific knowledge on application and standardization of various approaches like girdling of scionstick branches, age of mother plant, rootstocks, etc. of Kusum are extremely limited. Keeping these in view, an experiment was conducted during 2018–2021 to standardize grafting technique in Kusum. The result revealed that grafting methods affected the graft’s success significantly. Cleft grafting was found to be the most successful (72.38% graft) than veneer grafting (64.46%). Moreover, the scions collected from tree aged <15 years showed maximum success in grafting (upto 86.23%). This study revealed the importance of girdling of scionstick branches, girdling age (3 months), girdling-ring thickness (6–8 mm), and selection of two years old rootstock to maximize graft success upto 86.25% in Kusum. Furthermore, season also play an important role in successful grafting. The period from April to June was the best time for grafting with 73.31% success.