Biological Properties of Soil and Number of Coliform Bacteria in Water from Fruit Orchards of Pongrad area, Phlabphla subdistrict, Muang district, Chanthaburi province

Abstract

Microbiological properties are indicators for soil fertility and biological water quality. This research aimed to study the biological properties of orchard soil and analyse for coliform bacteria in agricultural water. Ten soil and water samples were collected from Pongrad area, Phlabphla subdistrict, Muang district, Chanthaburi province by two times of samplings, in September 2014 (after harvesting) and in December 2014 (in flowering). Soil samples were taken from the bush at a depth of 15 cm and was investigated for soil physico-chemical and microbiological properties. In September and December sampling, the results showed that pH, moisture and temperature of  soil samples ranged from 4.04 to 6.99, 4.04 to 6.66, 17.94 ± 0.36 to 33.98 ± 0.57%, 11.76 ± 0.29 to 24.50 ± 0.75%, 25 to 28 °C and 26 to 29 °C, respectively. Catalase activity of soil microorganisms in September and December sampling were ranged from 1.14 ± 0.04 to 1.84 ± 0.12, 1.10 ± 0.03 to 1.60 ± 0.07 ml O₂ g^-1 dry soil, basal soil respiration were ranged from 0.03 to 0.81 and 0.03 to 0.38 µg CO₂ g^-1 dry soil. The coliform numbers in agricultural water in September and December sampling were ranged from 11000 to 28000 and 7400 to 21000 MPN/100 ml for total coliform, 3600 to 9200 and 3000 to 7300 MPN/100 ml for fecal coliform. This study revealed that the physical and biological soils properties from the GAP-certified orchard and the conventional orchard were not significantly different (P = 0.05). Probably due to the collected sites had low degree of variability in soil type or land use pattern.