Terrestrial green algae diversity in oil palm plantation and secondary forest using 18S-rDNA PCR-DGGE approach

The demand for vegetables oils especially palm oil has increased drastically. However, rapid development in oil palm industry leads to many issues, especially regarding sustainable development of palm oil cultivation. Soil algae play an important role in the maintenance of soil fertility as well as recycling of soil organic matter. Their taxonomic knowledge in tropical soils is still scarce, especially in oil palm plantation. Hence, this study was performed to access the heterogeneity of soil algae community structure in response to oil palm plantation activities and compare with nearby secondary forest by using 18S-rDNA PCR-DGGE. Sampling was carried out in 3-years old oil palm plantation at Sungai Asap, Sarawak and nearby disturbed and undisturbed secondary forest. Significant differences in soil chemical properties and soil texture of oil palm plantation were evident: soil organic C, total N and CEC were significantly decreased. Oil palm plantation showed highest richness and diversity of the green algae, followed by disturbed secondary forest and undisturbed secondary forest. Three main clusters were obtained through UPGMA dendrogram generated with dice coefficient, one cluster from each sampling sites, except for some oil palm plantation sampling points were in the same clusteras with the disturbed secondary forest. Collectively, these results revealed that disturbance by both human or agricultural activity altered soil algae richness and diversity

Relationship between total carbon, total nitrogen and carbon to nitrogen ratio on growth, sporulation rate and δ-endotoxin synthesis of Bacillus thuringiensis.

The relationship between intracellular and extracellular total carbon, total nitrogen and carbon to nitrogen ratio on Bacillus thuringiensis MPK13 growth, sporulation rate and d-endotoxin synthesis were carried out in shake flask using different types of carbon (glucose, galactose, sucrose, lactose and maltose) and nitrogen (yeast extract) sources. The highest initial intracellular TC (5.15 g/L) and intracellular TN (1.45 g/L) were recorded in medium containing glucose. On the other hand, the highest initial extracellular TC (34.54 g/L) and TN (7.61 g/L) were recorded in medium containing maltose and lactose, respectively. At 48 h of cultivation, the highest final intracellular TC (11.96 g/L) and intracellular TN (3.26 g/L) were also recorded in medium containing glucose. The highest final extracellular TC (27.85 g/L) and TN (7.27 g/L) were recorded in medium containing galactose which showed the lowest growth and sporulation. The presence of d-endotoxin was only detected at 48 h of cultivation using medium containing glucose. The result indicated that high initial intracellular TC and TN values during the cultivation anticipated in high cell growth, sporulation and d-endotoxin production and may be used for indirect measurement of cultivation performance for B. thuringiensis

Changes in physicochemical and microbial community during co-composting of oil palm frond with palm oil mill effluent anaerobic sludge

The aims of this study were to investigate the physicochemical changes and microbial population during co-composting of 1 ton oil palm frond (OPF) with 1,000 L palm oil mill effluent (POME) anaerobic sludge. In the first 30 days of composting, the temperature of the composting piles was observed in the thermophilic phase, within a range of 50 - 56 °C. Meanwhile, the oxygen level, moisture content, and pH profiles of the compost were maintained at 2.0 to 12%, 60 to 70%, and 7.9 to 8.5, respectively, throughout the composting process. The total bacteria count was estimated to be about 55 x 1010 CFU/mL in the mesophilic phase, and then it increased up to 66 x 1010 CFU/mL in the thermophilic phase, and finally decreased to 9.0x1010 CFU/mL in the curing phase. The initial C/N ratio, 64, decreased to 18 after 60 days of composting process, indicating the maturity of compost product from OPF-POME anaerobic sludge. The diversity of the bacterial community was investigated using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. The results suggested that the co-composting process of OPF with POME anaerobic sludge was dominated by Pseudomonas sp

Persepsi pelajar berisiko terhadap iklim pembelajaran

Learning is a process which occurs in a social context. The streaming of students into academically weak classrooms creates a negative learning context or climate for teaching and learning. Therefore, the risk of failure increases among these students in their learning process. As such, it is important to understand the learning climate in these classrooms in order to overcome the problems of at-risk students. This paper attempts to highlight the findings of a study pertaining to perceptions of students toward their classroom learning climate, involving 1,689 form two students from 28 schools in Kuala Lumpur and Selangor. Data were gathered by utilizing the questionnaire and analyzed descriptively. The findings reveal that in general, students in the various streams perceive their classroom learning climate as moderate. However there is a significant difference in perceptions of students from the three streams studied, with regards to their teachers in terms of their treatment of students, their teaching approaches and their expectations of their students. High achievers have more positive perception towards their teachers, as compared to the low and extremely low achievers. Implications of the findings and some suggestions are also discussed

At-Risk Students' Response to Learning Mathematics and Science in a Second Language

The Malaysian government recently reverted to the English language as the medium of instruction in its education system for important content subjects such as Mathematics and the Sciences. This policy decision was made in the midst of widespread concern over the perceived falling standards of English language proficiency after the country had used Malay, the native language of the majority Malays, as the medium of instruction for almost two decades. This year marks the first year high school students will sit for the national standardized examinations in English. Dissenters to this policy shift in the language of instruction fear that many will suffer as a result of this change. In this study, the self reports of academically high and low performing students are compared in terms of their ability to perform language related tasks in Malay and the English language. Using the Chi-square statistic, the results of the yes-no responses given by the students indicate that while high performing students report no major difficulties in either language, responses from the low performing students indicate otherwise. Additionally open-ended responses to learning Science and Mathematics in a second language are also qualitatively analysed in order to obtain a more comprehensive view of the challenges these students may face. Several implications based on these results are also discussed

Bunch moth, Tirathaba rufivena (lepidoptera: pyralidae) infestation census from oil palm plantation on peat soil in Sarawak

Tirathaba rufivena is the major pest in oil palm plantation planted in peat soil in Sarawak. High infestation was reported in Miri, Mukah and Sibu. Censuses on the infestation of T. rufivena were conducted at three different locations, i.e. in Miri (young palm), Mukah (mature palm) and Sibu (ablation samples). Samples for census were taken from infested bunches, female and male inflorescences. The census was done by chopping the bunches and the female inflorescences while for the male inflorescences, the bottom of spikelets were cut to determine the number of live larvae and pupae. The census reveiled that in Sibu, a high infestation of T. rufivena was found on male inflorescences compared to bunches of female inflorescences. The mean number of live larvae found in male inflorescences for the first and second day of census recorded 35.3 ± 15.7 and 14.0 ± 7.3, respectively. The highest number of live larvae recorded from male inflorescences was 207 and 65, respectively. Meanwhile, the mean number of live larvae from infested bunches and female inflorescences on the first day were 9.9 ± 3.5 and 19.4 ± 4.4, respectively. On the second day of census, the mean number of live larvae recorded on bunches and female inflorescences were 4.8 ± 1.5 and 12.7 ± 2.8, respectively. Census on infested area in Miri from three different stages of female inflorescence and bunches recorded 8.0 ± 1.9 and 4.8 ± 0.6 highest number of live larvae. Post anthesis female inflorescences recorded the highest mean number of live larvae compared to pre anthesis and anthesising female inflorescences. Population study at Mukah on highly infested area recorded 60 live larvae from young bunches and 50 live larvae from matured female inflorescences. Based on the samples, bunch moth larvae or pupae were absent in 10% of infested female inflorescences and 11.7% of infested bunches (males and females inflorescences)

Composition of soil fungi in oil palm plantation, Sungai Asap, Sarawak.

Oil palm industry in MAlaysia is expanding rapidly due to high demand from cooking oil and biofuel markets worldwide. The oil palm plantation activities may lead to biodiversity loss to certain extent. A study was carried out to compare the composition of soil fungi in oil palm plantation and the adjacent secondary forest in Sungai Asap, Sarawak using denaturing gradient gel electrophoresis (DGGE). Amplification of fungal 185 rDNA was achieved with universal primers. A total of 122.77 and 95 fungi were recorded from two forest soils and a plantation soil. Sequence analysis and cluster analysis pf prominent DGGE bands showed that the fungal community in plantation was different from those in the forests. Two main ohyla were observed namely Ascomycota and Basidiomycota. Forest soils consist of 67.9% and 53% of Basidiomycota whereas 30.3% and 47% were Ascomycota. In contrast, 12.8% Basidiomycota and 87.2%. Ascomycota were found in plantation soil. From the resresentative bands, sequences showed 1 fungus were common between two forest sites, 5 funsi species were common between secondary forest and plantation soil yet no common species were found among the three study sites. Some groups of the soil fungi could be potentially used as indicator to access soil quality at oil plam plantation

Molecular diversity of soil ciliates in Borneo tropical secondary forests

Ciliates are unicellular eukaryotes and play important roles in soil processes. Their significant contributions in soil cause the growing interest in studying soil ciliates for monitoring biodiversity and soil quality. However, knowledge of their regional and global diversity is insufficient due to the limits of the conventional methods. Thus, the objective of this study was to investigate the diversity of soil ciliates in Borneo (Bintulu, Sarawak) using semi-nested polymerase chain reaction reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Soil samples were collected in two tropical secondary forests from December 2010 to June 2011. Primer sets EukA/CilDGGE-r and CilF- GC/CilDGGE-r were used in semi-nested PCR to amplify soil ciliate 18S rDNA. DGGE profiles revealed a total of 83 predominant bands which were then excised and sequenced. Majority (99%) of these bands matched ciliate 18S rDNA in the GenBank with the similarity of 91% and above. Phylogenetic analysis showed that these sequences belonged to 34 species which affiliated to 6 classes, 13 orders, 17 families and 19 genera. The forest soils were dominated by Litostomatea, Colpodea, Spirotrichea and Oligohymenophorea, followed by two rare groups which were the Armophorea and Heterotrichea. Statistical analyses revealed that the diversity and community structure of soil ciliates were different among the sampling sites and across time. The semi-nested PCR-DGGE approach in this study has served as a fast and useful method in studying soil ciliates. New combinations of primer sets presented herein contributed to the choices of 18S rDNA specific primers for PCR-DGGE analysis of soil ciliates. Our findings revealed an insight into the diversity of soil ciliates in Borneo tropical secondary forests

Persepsi pelajar berisiko terhadap iklim pembelajaran

Learning is a process which occurs in a social context. The streaming of students into academically weak classrooms creates a negative learning context or climate for teaching and learning. Therefore, the risk of failure increases among these students in their learning process. As such, it is important to understand the learning climate in these classrooms in order to overcome the problems of at-risk students. This paper attempts to highlight the findings of a study pertaining to perceptions of students toward their classroom learning climate, involving 1,689 form two students from 28 schools in Kuala Lumpur and Selangor. Data were gathered by utilizing the questionnaire and analyzed descriptively. The findings reveal that in general, students in the various streams perceive their classroom learning climate as moderate. However there is a significant difference in perceptions of students from the three streams studied, with regards to their teachers in terms of their treatment of students, their teaching approaches and their expectations of their students. High achievers have more positive perception towards their teachers, as compared to the low and extremely low achievers. Implications of the findings and some suggestions are also discussed