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Sustainability of the oil palm in Malaysia is threatened by Ganoderma species causing stem rot. There were many studies conducted to understand the etiology and epidemiology of the disease in West Malaysia, however none of them reported the situation in Sabah, one of the leading producers. Moreover, the mode of Ganoderma spread in oil palm is least understood. Thus, the aims for this study were to investigate the infection mode of Ganoderma species in oil palm based on the in-vitro cultural characteristics and somatic compatibility. A total of 21 Ganoderma basidiocarps were isolated from stem rot infected palms in an estate in Sandakan, Sabah. These samples were obtained (i) within infected palms; (ii) among infected neighbouring palms; and (iii) five clusters of infected palms. In-vitro morphology of the Ganoderma isolates was characterized based on 21 characteristics via a dendrogram. Somatic compatibility was accessed to investigate the genetic heterogenicity. There was a narrow variability (93 to 100%) in terms of the cultural characteristics, and the variations exhibited among the isolates regardless of their origin. The isolates may exhibit similar phenotype, but not necessarily have similar genotype, and vice versa. Based on the somatic compatibility test, it was found that all pairings showed incompatible reactions except in self-pairing and between isolates C5P3-1 and C5P3-2 which were isolated from the same infected palm (genetically identical). These findings indicated that infection of Ganoderma in a single palm and neighbouring palms generally were caused by multiple unidentical strains. This further concludes that spread of Ganoderma species in oil palm via rootto-root contact is uncommon. Thus, the basidiospores may play an important role in the disease epidemiology, and further research and management strategies of the disease should focus on this.

Satu kajian telah dijalankan untuk menyiasat kesan ketoksikan insektisid Bacillus thurigiensis subsp kurstaki (Bt kurstak1) antara Ladang Persendirian (Ladang 1) dan Ladang Syarikat Majulah Sdn Bhd (Ladang 2) yang terletak di Sg. Batang, Sandakan terhadap mortaliti larva kumbang badak ( Oryctes rhinoceros L.) perosak kelapa sawit. Kajian ini telah dijalankan di Makmal Entomologi Fakulti Pertanian Lestari, Universiti Malaysia Sabah, Kampus Sandakan yang terletak di Batu 10 Sungai Batang, Sandakan, Sabah selama 2 bulan (Ogas 2016 hingga Oktober 2016). Objektif kajian ini adalah untuk menentukan 'Lethal Dose (LDso atau LD90) mengikut masa dan pertambahan dos insektisid serta faktor kerintangan (FRso atau FR90) bagi mortaliti larva Oryctes rhinoceros terhadap insektisid Bt kurstaki. Sebanyak 4 rawatan (ng/g) telah digunakan termasuk dos kawalan (0 ng/g, 6.Sx105 ng/g, 13x105 ng/g, 26x105 ng/g). Setiap rawatan mempunyai 3 replikasi dan disusun menggunakan rekabentuk Completely randomized Design (CRD). Semua data dianalisis dengan menggunakan analisis PROBIT dengan perisian POLO PLUS. Bt kurstaki (mengikut dos kepekatan) disembur ke atas makanan larva kumbang badak dan kadar mortaliti larva kumbang badak telah direkod setiap 24 sehingga jam ke 96. Keputusan kajian mendapatl bahawa terdapat perbezaan bererti pada tahap ketoksikan insektisid Bt kurstaki terhadap mortaliti larva Oryctes rhinoceros di kedua-dua kawasan kajian. Hasil kajian menunjukkan bahawa kadar peratusan mortaliti probit selama 96 jam untuk Ladang 1 (93.33%) adalah lebih tinggi berbanding Ladang 2 (40%). Hipotesis 'parallelism' menunjukkan bahawa tidak terdapat perbezaan bererti bagi kesan relatif kimia pada bahan aktif Bt kurstaki di Ladang 1 (x2= 0.03, df= 3, p=0.999) dan Ladang 2 (x2= 0.13, df= 3, p= 0.988). Hipotesis 'equality' juga menunjukkan bahawa tidak terdapat perbezaan bererti bagi tindak balas populasi di Ladang 1 (x2= 1.63, df= 6, p=0.951) dan Ladang 2 (x2= 0.75, df= 6, p=0.993). Kedua-dua ujia