Standardisation of nursery management practices in pachotti (Symplocos cochinchinensis (Lour.) S. Moore)

Abstract

The study entitled “Standardisation of nursery management practices in pachotti (Symplocos cochinchinennsis (Lour.) S. Moore)” was carried out in the Department of Plantation Crops and spices, College of Agriculture, Vellayani durng 2017-18. The objective of the study was to evaluate the propagation efficiency of different propagules viz., seeds, stem cuttings and root cuttings and to standardise the potting media for the nursery plants of pachotti. The propagules viz., seeds, stem cuttings and root cuttings for the study were sourced form Jawaharlal Nehru tropical Botanical Gardens and Research Institute, Palode, Thiruvananthapuram and from Wayanad district. The seeds were subjected to in vivo and in vitro germination studies. In in vivo study, among the pretreatments tried, viz., physical treatments, chemical priming and bio priming, only physical treatment of scarification (with sand paper) responded with a very low germination of 2 per cent. The germination commenced after two months of the treatment. Other in vivo pretreatments as well as in vitro treatments did not give any germination. In vegetative propagation, stem cuttings were exposed dto hormone/chemicals (auxins, phloroglucinol and salicylic acid (SA) pretreatments for two hours before planting. When pretreated with SA @ 10 and 20 mg L -1, at three months after planting, the hardwood cuttings responded with 30 pere cent survival, whith a shoot length of 2.99 mcm and 3.62cm, respectively. The semihardwood cuttings pretreated with SA@ 20 mg L-1 responded with 23.33 per cent survival with a higher shoot length of 3.72 cm. Both the hardwood and semi hardwood cuttings pretreated with SA 20 mgL-1 had on par values with respect to shoot length. Root cuttings were pretreated with different concentrations of various types of auxins. Root cuttings pretreated with IAA @ 250 mg L -1, after three months of planting responded with 33.33 per cent survival with a shoot length of 5.73 cm. Though root cuttings had slightly higher survival percent and shoot length, hardwood cuttings were selected for the valuation of potting media due to better availability and ease in procurement. The three month old hardwood cuttings pretreated with SA @ mgL-1 were then transplanted to ten different potting media comprising of two basal media viz., soil:coipith compost :cowdung (1:1:1) (B1) and soil : soirpith compost : vermicompost (1:1:1) (B2), and each in combination with biofertilisers @ 5g plant -1 viz., PGPR (Plant Growth Promotng Rhizobacteria) Mix I, Azospirillum, PSB (Phosphorus Solubilising Bacteria ) and AMF (Arbuscular Mycorrhizal Fungi). At fourth month after transplanting, B2 in combination with biofertilisers were found to be significantly superior to B2, B1 and B1 in combination with biofertilisers with respect to morphological parameters. B2 +PGPR Mix I recorded highest shoot length (11.50 cm) and number of leaves (10.50) which was on par with B2+Azospirillum, B2+PSB and B2+AMF; the highest number of branches (1.92) was observed in B2+ Azospiriillum which was on par with the treatments , B2+ PGPR Mix I, B2+PSB and B2+AMF. The fresh and dry weight of shoots were the highest (21.35 g and 4.78 g respectively) in B2 +PGPR Mix I which was on par with B2+ AMF. B2+ AMF recorded highest values (4.77 cm, 0.30 mm, 3.28 g and 0.0092 g, respectively) with respect to root growth parameters viz., root length, root girth , fresh and dry weight of roots. The physiological parameters, leaf area index (1.36) and leaf area duration (34.63 days) were the highest in B2+ PGPR Mix I which was on par with B2 in combination with other biofertilisers. The phytochemical analysis indicated that carbohydrate content (80.9 mg g-1) of plant tissue was the highest in B2+PGPR Mix 1, which was on par with B2+PSB, B2+Azospirrillum and B2+AMF. Chlorophyll content was found to the highest (1.20 mg g-1) in B2+ Azospirillum which was on par with B2+PGPR Mix I. The same treatment recorded the highest soluble protein content (20.31mg g-1) and it was on par with B2 in combination other biofertilisers. The nutrient analysis of plant tissue showed that nitrogen (2.22 percent ) and potassium (2.15 per cent ) content was significantly higher in B2+ Azospirillum. B2+PSB Recorded higher phosphorus content (0.26 per cent) among the treatments. The study indicated that nursery plants in the potting media B2 in combination with biofertilizers gave better performance with respect to morphological parmeters, physiological parameters, phytochemicals and plant nutrients. Among the various potting media tried, B2+AMF recorded significantly higher plant growth potential (0.522) followed by B2 + PGPR Mix I (0.428). In the study, hardwood cuttings were identified as the preferred planting material for the nursery establishment of pachotti. The cuttings could be treated with salicylic acid @ 20 mg L-1 for initial establishment of nursery plants. The preferred potting media for transplanting the established cuttings for raising the nursery plants of pachotti is Soil : Coirpith compost : Vermicompost (1:1:1) +AMF (5g/plant).