PhD

The research project entitled “Investigations on agroforestry models suitable for Sothern high hills of Kerala” was carried out Adimali and Mankulam Panchayaths, Idukki district, Kerala during 2020-2022. The main objective of the study was to conduct on- farm trials of silvopastoral practices in the selected farmer field, to screen suitable bamboo species for the selected panchayath and to explore the soil fertility changes associated with these intercropping systems. In case of on- farm trials of silvopatoral practices the treatment consisted of four fodder tree species (Calliandra, Kadamba, Gliricidia and Mulberry) with plant density (45cm x 45 cm) and cutting frequency (12 weeks) in a randomized block design with five replications. In the second experiment ie. trial on screening of bamboo species, the treatment consisted of five promising bamboo species (Dendrocalamus asper, Dendrocalamus brandisii, Dendrocalamus strictus, Bambusa balcooa, and Dendrocalamus stocksii) with 5m x 5m spacing in a randomized block design.
The result revealed that Gliricidia, Calliandra, Mulberry and Kadamba produced comparable dry fodder yield under farmland. Annual dry forage yield was significantly higher in Calliandra with 7.71 Mg ha-1 yr-1. Significant variation was also noticed with regard to proximate composition. The leaf crude protein content in fodder biomass was significantly higher in cases of Gliricidia with 53.21 per cent. Comparing the fodder tree species Calliandra shows significantly lower crude fibre (19.90 per cent) than the other fodder trees. However, Mulberry had 147 higher ash (17.28 per cent) and P content (0.23 per cent) than other fodder trees.
Intercropping fodder trees (Gliricidia, Calliandra, Mulberry, Kadamba) under the farmland produced significant changes in some soil parameters after the initial year of establishment. In comparison to the open plot, soil properties particularly the soil organic carbon was improved.
Precisely, the fodder trees significantly influenced the total and seasonal forage yield and proximate composition. The annual fresh forage and dry forage yield was significantly higher in case of Calliandra with 29.14 and 7.71 Mg ha-1yr-1 respectively. Calliandra recorded significantly high biomass of 3.71 Mg ha-1 and 14.22 Mg ha-1 respectively in dry and wet seasons. However, Mulberry contains highest of potassium (2.70per cent), phosphorus (0.23per cent) and ash content (17.28per cent).
While screening the bamboo species planted at Mankulam, the initial growth performance was significantly higher in case of Dendrocalamus strictus (T3) with higher clump length (111.42 cm), number of nodes (8.47) and current year shoots (23.06) followed by Dendrocalamus brandisii with clump length of 96.75cm at one year of growth. Both these bamboo species are promising in this part of southern high hills of Idukki.