Standardization of techniques for better rooting and growth of orthotropic shoots in black pepper (Piper nigrum L.)

Abstract

The present study on “Standardization of techniques for better rooting and growth of orthotropic shoots in black pepper (Piper nigrum L.)” was carried out at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during 2012- 2014. The objective of the study was to standardize techniques for profuse rooting and vigorous growth of orthotropic shoots of black pepper so as to produce quality planting material. The experiment was laid out in completely randomized design consisting of 10 treatments with 3 replications. All the treatments were tried using 2 node and 3 node semi hardwood cuttings of orthotropic shoots of black pepper. The treatments consisted of IBA (500 ppm and 1000 ppm), common sugar solution (1 per cent, 2 per cent and 3 per cent), AMF, Azospirillum 15 per cent and Psuedomonas 15 per cent. Solarized potting mixture enriched with Trichoderma was used for all the treatments including control and PGPR Mix -II was drenched uniformly in all treatments except absolute control. In the experiment with 2 node cuttings, T7 (Azospirillum 15 per cent) was found to be superior for most of the growth characters like minimum number of days for sprouting and number of days for 50 per cent sprouting . The same treatment recorded the highest value for height of sprouted cutting, length of leaf, breadth of leaf and leaf area. But the maximum values for number of leaves, petiole length, internodal length, root volume and number of roots was recorded in T2 (IBA 1000 ppm). In experiment with 3 node cuttings, T2 registered minimum number of days for sprouting, number of days for 50 per cent sprouting, highest values for height of sprouted cutting, number of leaves, petiole length, number of roots and root volume. The anatomical characters when studied, leaf cuticle thickness was highest in 2 node cuttings treated with T5 (common sugar solution 3 per cent) and in 3 node cuttings treated with T6 (AMF). The number of vascular bundles in leaf was found highest in T2 (IBA 1000 ppm) for both 2 node and 3 node cuttings. But the number of vascular bundles in root was highest in T1 (IBA 500 ppm), both in the case of 2 node and 3 node cuttings. For stomatal frequency, T7 showed maximum value in both the cases. The treatment T8 (Psuedomonas 15 per cent) recorded highest value for total dry matter production in both the experiments. The biological properties of potting mixture (after the experiment) showed that, AMF colonization and spore count was maximum in T6 for 2 node and 3 node cuttings .The observation on total actinomycetes load was highest in T7 in both the experiments. The treatment, T7 showed the highest percentage of success in the establishment of 2 node orthotropic cuttings which was on par with T1 and T2. With 3 node cuttings also T7 and T1 showed highest percentage success in the establishment of cuttings. From the results, it can be concluded that 2 or 3 node cuttings with Azospirillum 15 per cent or IBA 1000 ppm or IBA 500 ppm were found to be the best treatments for better rooting and growth of orthotropic shoots in black pepper (Piper nigrum L.) when planted in solarized potting mixture enriched with Trichoderma. However, 2 node cuttings are preferred because the availability of orthotropic shoots are scarce in black pepper.