Vegetative propagation in jamun (Syzygium cumini (L.) Skeels)

Abstract

Jamun (Syzygium cumini (L.) Skeels) is a popular, but underutilised indigenous fruit crop in India with high nutritive value. It can be multiplied through both seed and vegetative propagation methods. Due to the long juvenile period, huge size of the tree and short shelf life of fruits, jamun is not preferred for commercial cultivation in Kerala. As jamun fruits are highly nutritious and possess good medicinal properties, there is an urgent need to commercialise this crop in Kerala. To achieve this goal, availability of true to type, early bearing and dwarf statured clones of superior jamun types should be assured in sufficient quantity and this can be achieved only through vegetative propagation methods. Under this context, the present study entitled “Vegetative propagation in jamun (Syzygium cumini (L.) Skeels)” was carried out in the Department of Fruit Science, College of Agriculture, Vellanikkara during the year 2021-2022 with the objective of standardizing an effective vegetative method of propagation in this fruit crop. The research programme consisted of four experiments. The first experiment was on propagation by hardwood cuttings which was laid out in CRD with two factors and was done during June (2022). The first factor was growth stimulants with six treatments viz., T1 (AMF), T2 (IBA), T3 (Pseudomonas fluorescens), T4 (Aloe vera gel), T5 (Cow dung slurry) and T6 (Tender coconut water). The second factor was growing condition with two treatments, T1 (Mist chamber) and T2 (Shade house). All these treatments were replicated thrice with twenty plants in each replication. The cuttings kept under mist chamber started sprouting earlier (8.49 days) than those cuttings kept under shade house (11.09 days). Though sprouting was observed, after one month the plants started to dry up and failed to develop roots and did not survive under both growing conditions. The second experiment, propagation by air layering was done during November (2021) and was laid out in CRD with five treatments replicated thrice with twenty plants per replication. Treatments were T1 (Coir pith compost), T2 (Vermicompost), T3 (Sphagnum moss), T4 (Saw dust), and T5 (FYM). Minimum number of days for the emergence of roots (55 days) in air layers was recorded in T2 (Vermicompost) and longest root was observed in T1 (Coir pith compost). Though the air layers produced using sphagnum moss (T3) and coir pith compost (T1) survived during the experiment period, the survival percentage (6.67% and 5.00% respectively) was very low and were found to be on par with each other. Air layers produced using vermicompost, saw dust and FYM as the media rooted but failed to survive till the end of the experiment. The third experiment (propagation using budding) was also laid out in CRD with six treatments replicated thrice with twenty plants in each replication and it was carried out during the month of June (2022). The budding methods tried were T1 (T budding), T2 (Patch budding), T3 (Forkert budding), T4 (Flute budding), T5 (Ring budding) and T6 (Yemma budding). These budding methods failed to sprout except patch budded plants which took 102.78 days for initial sprouting and about 10.00 per cent of patch budded plants were found to survive 190 days after budding. The fourth experiment, propagation using grafting, was also laid out in CRD with eight treatments replicated thrice with twenty plants in each replication and it was also done during June (2022). The methods of grafting tried were T1 (Epicotyl grafting), T2 (Softwood grafting), T3 (Whip grafting), T4 (Whip and tongue grafting), T5 (Veneer grafting) and T6 (Approach grafting), T7 (Wedge grafting on one year old rootstock) and T8 (Wedge grafting on three year old rootstock). Results from the present study showed that hardwood cuttings, air layering and budding methods were not suitable for commercial propagation of jamun plants under the climatic conditions prevailing in Thrissur. Among the grafting methods, wedge grafting done on three year old rootstock showed better growth performance with respect to production of maximum number of leaves and shoots and also longest shoot (17.73, 3.55 and 16.40 cm respectively). With regard to survival rate, wedge grafting performed on one year old rootstock of jamun was found to be the best (53.33% survival) among the different methods of grafting carried out during the period under study.