Influence of base mulch substrate on growth attributes of vanilla (Vanilla planifolia)

Vanilla (Vanilla planifolia) popularly referred as princess of spices belongs to the family Orchidaceae. Vanilla is a rich source of flavor as natural vanillin is the most preferred flavoring component among the global confectionaries industry and widely used as a flavoring agent in cakes, sweets, chocolates, ice creams, beverages and condiments as well as in the cosmetics and perfumery industries. Information on plant base or rhizosphere management through base mulching and type of mulch substrate is lacking currently. Hence an observational study was taken up at Indian Cardamom Research Institute, Regional Research Station, Spices Board, Sakleshpur during 2017-2020. Two to three node cuttings of Vanilla plants were planted using glyricidia as standard tree in June, 2018. Experiment consisting 5 treatments with four replications was laid out in Randomized Block Design. Higher length of vines was observed in the treatments where plants base was mulched with charcoal during both the observation schedules (509.6 & 624.3 cm). Increased vine length and number of leaves per vine has positive influence for leaf area. Hence treatments receiving plant base mulch with Charcoal (640.22 & 802.12 cm²) tree log chips (5285.36 & 724.36 cm²) and coconut husk (608.16 & 612.14 cm²) recorded significantly higher leaf area as compared to vanilla plants without base mulching. Among the treatments plant base mulching with charcoal, tree log chips and coconut husk recorded significantly longer internodal length. Supplementing various organic substrates as mulch material like charcoal, coconut husk and tree log chips ensures to facilitate better drainage, aeration and perfect encourage for the root mass of vanilla plant. Vanilla being a sciophytic epiphyte needs favourable rhizosphere especially during monsoon period. Rhizosphere modification influences on per cent disease incidence also. Relatively lowest incidence of block rot disease and stem rot disease was observed in treatment receiving charcoal as vanilla plant base mulch. Hence, it can be concluded from the results of the current study that, appropriate modification in the rhizosphere for vanilla crop using locally available slow degrading organic substrates like charcoal, coconut husk and tree log chips supports growth of vanilla vine and also minimizes incidence of important disease also.