SOIL MICROFLORA AND BIOLOGICAL-ACTIVITIES IN THE RHIZOSPHERES AND ROOT REGIONS OF COCONUT-BASED MULTISTORIED CROPPING AND COCONUT MONOCROPPING SYSTEMS

Microflora, enzyme activities, microbial biomass, C and N mineralization in the rhizosphere and root region soils of coconut-based multistoreyed cropping (pepper, cacao and pineapple) and coconut monocropping systems were studied. The rhizospheres of the different crops had greater numbers of microflora than non-rhizosphere soils. There were fewer bacteria and fungi in the root region soils of coconut monocrop as compared to multistoreyed cropping system. The microflora, enzyme activities, C and N mineralization decreased with soil depth. Urease, dehydrogenase and phosphatase activities showed variable trends in the root regions and rhizospheres of the different crops. The microbial biomass in the root region soil was highest in the coconut and cacao of the multistoreyed cropping system. The organic C, total N, P and K were higher in the root region soils of multistoreyed cropping system than in the coconut monocropping system.