Microbial inoculants enhance the rooting and establishment of stem cuttings of cvs. Ruby and Mrudula of pomegranate (Punica granatum L.) for propagation

Abstract

The influence of different microbial inoculants and their combination for inducing rooting in hardwood cuttings of pomegranate cv. Ruby and Mrudula in greenhouse and open condition was studied. Shoot and root parameter such as days taken for first sprouting, length of sprouts, plant height number and length of roots, dry weight of shoot and root, percentage of rooting were analysed. Among various microbial cultures used Trichoderma + Azotobacter each at 2.5 ml/kg of potting mixture resulted in maximum number of branches, diameter of shoot and plant height, followed by IBA 2000 ppm + Azotobacter at 5 ml / kg of potting mixture and IBA 2000 ppm + Trichodermaat 5 ml / kg of potting mixture. Maximum number of sprouts per cutting recorded at weekly interval and length of shoot recorded on 30th day after planting till 90th day after planting were observed in cv. Ruby, when treated with microbial inoculants vi iz., Azotobacter + Trichoderma each at 2.5 ml /kg of potting mixture. High number of adventitious roots, secondary roots, length of longest adventitious root, length of longest secondary root and establishment after transplanting were also in cv. Ruby compared to cv. Mrudula. Cuttings under high cost greenhouse performed better with respect to both vegetative parameters and root parameters than those kept in open condition. The interaction effect of varieties, microbial inoculants and growing condition also influence various shoot and root parameters of hardwood cuttings. The combination of IBA @ 2000 ppm +Azotobacterat 5 ml /kg of potting mixture performed better in greenhouse condition. Therefore, it is advisable to use microbial consortia in place of IBA, since it is cheaper and provides other benefits apart from producing quality, planting material which will be cost effective. Further, treating the cutting with IBA @ 2000 ppm + Trichoderma@ 5 ml/ kg of potting mixture (T6) under greenhouse gave better results while under open condition the treatment with Azotobacter + Trichoderma each @ 2.5 ml/kg of potting mixture (T4) was economically feasible for propagation of pomegranate.