Wong , Wan Chew (2008) Spatial and temporal epidemiology of basal stem rot in oil palm (Elaeis guineensis) in Tawau Region, Sabah. Masters thesis, Universiti Malaysia Sabah.
Intense oil palm monoculture has resulted pathogenic diseases, pests and physiological disorders, especially basal stem rot. The BSR disease was believed caused by Ganoderma boninense (fungal pathogen). The actual mechanisms of infection was ambiguous, even though controls and treatments of BSR disease only aimed to prolonging productivity life of oil palm. The objectives of present study were to determine the relationship between the incidences of external visible disease symptoms (recorded by visual census) and subclinical symptoms (detected by GSM test) with soil properties. The study site located in Tawau region, state of Sabah. It was situated in a flat landscape with three different of soil type namely Inanam series, lumisir and Paliu with 9x9x9 m in planting density. Sampling design was divided into four main parts included mapping disease incidence, visual census assessment on oil palms, Ganoderma infection detection employed with Ganoderma selective medium technique (GSM), and soil sampling. In this present study, GSM test has been demonstrated that 8.5 % of total palms were infected, however they still appeared healthy. In addition, semi-variogram analysis revealed infected palms had a short distance of spatial dependency to their surrounding palms (1 to 2 palms) and small-scale spread of an agent might be occurred. The possible agents might be air-borne spores through human, insect and animals or spread via root-to-root contact. At topsoil layer, subclinical symptoms were positive correlated with soil pH, coarse sand and fine sand whereas negative correlated with organic C, clay, slit, AI, available P, total P, total N, Ca, Mg, K and CEC.
|Item Type:||Thesis (Masters)|
|Uncontrolled Keywords:||oil palm, basal stem rot, soil, spatial, Ganoderma boninense|
|Subjects:||T Technology > TD Environmental technology. Sanitary engineering|
|Divisions:||SCHOOL > School of Science and Technology|
|Deposited By:||IR Admin|
|Deposited On:||23 Jun 2014 13:28|
|Last Modified:||23 Jun 2014 13:28|
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