PRODUCTIVITY OF COCONUT BASED MULTI-TIER CROPPING SYSTEMS IN RELATION TO FERTILITY STATUS OF THE SOIL

Author : SMITHA THOMAS Title of the thesis : PRODUCTIVITY OF COCONUT BASED MULTI-TIER CROPPING SYSTEMS IN RELATION TO FERTILITY STATUS OF THE SOIL Submitted for the award of degree : Master of Science in Agriculture Faculty : Agriculture Discipline : Soil Science and Agriculture Chemistry Major advisor : Dr. N. RAMAVATHARAM University : ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY Year of submission : 2003 A survey was carried out in Trivandrum district of Kerala to study the yield and productivity of coconut based multi-tier cropping systems in relation to the fertility status of the soil and correlation coefficients worked out to find the relationship between soil and leaf nutrients and between leaf nutrients and yield. The study was carried out in the year 2003. The different cropping systems selected were coconut monocropping system, coconut-pepper-nutmeg-banana (C-P-N-B), coconut-pepper-nutmegcassava (C-P-N-C), coconut-pepper-cocoa-vegetable cowpea (C-P-C-V) and coconut-pepper-cocoa-ginger (C-P-C-G). Soils of the area selected for the study are red sandy clay loams, acidic and non-saline in nature with low to medium in organic carbon. The available nitrogen content was low, available phosphorous was medium, available potassium was low and Fe, Mn, Zu and Cu were above the critical limits. The study showed that as a result of multi-tier cropping systems, the available N, P, K and Ca content of soils increased, whereas Mg, S, Fe, Mn, Zn and Cu content decreased. The leaf nutrient concentration of all the nutrients studied in index leaf of coconut was more in multi-tier cropping systems, compared to coconut monocrop. Simple correlations worked out between soil and leaf nutrients showed significant positive relationship with respect to N, P, K and Ca. Consistent positive but not significant correlations were observed for P, K and Ca in pepper, for P, Ca, Mg, Fe and Mn in nutmeg and for N, K and Zn in cocoa. Significant positive correlations were observed for N, K, Ca in coconut leaf and yield, whereas a consistent positive correlation was observed for leaf P and yield. The average nut yield of coconut recorded in mono-cropped system was 69.5 nuts/palm/year, while it was 92.3 in C-P-N-B, 80.8 in C-P-N-C, 87.1 in C-P-C-V and 77.6 in C-P-C-G, which represents an increase of 32.8, 16.25, 25.3 and 11.65 per cent, respectively, over coconut mono-crop.