Download Latest Complete Journal - JTAS Vol. 43 (2) May. 2020
Foreword by the Chief Executive Editor
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Abstract (Viewed: 20)The sago palm (Metroxylon sagu Rottb.) is one of the underdogs in the food crop planting industries for its potential which is extremely vast but the community appreciating it is scarce. Its capabilities to thrive well in undesirable environmental conditions, salt tolerance and high starch yield are one of the many advantages it possesses over other food crops like wheat, corn and rice. One important factor to look into for crop plantation is none other than its salt tolerance. The salt tolerance researches on this unique palm have commenced since 1977 and the pace of research was unbelievably slow in progression. Nevertheless, it was not until recently that this palm was being placed in the limelight once more. In this review, we are focusing on salt tolerance research and further detailed on the past, present and future of this research line. It is anticipated that consolidation of talents and resources can come in time and in tandem for the utilization of this cash palm to end world hunger.Food crop, food security, sago palm, salt tolerance, starch yield
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Abstract (Viewed: 6)An investigation was conducted to determine the antifungal potential of Andrographis paniculate, Backhousia citriodora, Clinacanthus nutans, Ficus deltoidei, Phaleria macrocarpa, and Piper betle against selected plant fungal pathogens. Dilutions of crude leaf extracts (5, 10, 15, and 20%) of these plants were screened in vitro against Ganoderma boninense, Fusarium oxysporum f. sp. cubense R4 (FocR4), and Rhizoctonia solani. The percentage inhibition of diameter growth (PIDG) of test pathogens was measured using poisoned agar method. Aqueous extract of A. paniculate was ineffective in inhibiting the mycelial growth of test pathogens at all test concentrations while that of B. citriodora markedly inhibited FocR4 growth at 15% (PIDG 70%) and 20% (PIDG 72.9%) concentrations. Methanol extract of C. nutans at 20% concentration significantly inhibited R. solani growth (PIDG 64.4%) meanwhile that of P. betle at 20% considerably inhibited the growth of FocR4 (PIDG 94%), G. boninense (PIDG 89.4%), and R. solani (PIDG 82.8%). Complete inhibition (PIDG 100%) of G. boninense and R. solani was obtained at 10% concentration of F. deltoidei and P. macrocarpa methanol extracts. Leaf extracts of five herbal plants have the potential to be used as bio-fungicides as a safe alternative to synthetic fungicides.Biopesticide, botanical extract, green technology, poisoned agar method
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Abstract (Viewed: 5)About two-thirds of crude oil is produced in countries with tropical and subtropical climates. Many sites in these regions have been threatened by oil spills that can adversely affect soil physical, chemical and biological properties. In some tropical countries, such as Mexico, Venezuela, India, and Nigeria, studies have been conducted to evaluate the effects of petroleum spills on soil fertility, often by monitoring pasture germination or contaminant toxicity. It has been observed that most common impacts to petroleum-contaminated soil occur by two mechanisms: a) by the formation of a thin layer of hydrocarbons on soil particles that results in a reduction in field capacity and causes soil water repellency; and b) by the formation of macro-aggregates (agglomeration) of fine soil particles into coarse particles, thus causing compaction and reduced porosity in the soil. In these studies, it appears that the type and quantity of soil clays influence how severe these impacts may be, being mitigated in the presence of higher contents of smectite clays and being more intense in soils with other fine materials (silts, kaolinite clays, Fe/Al oxides). However, these results have been observed as circumstantial evidence in natural soils. To better understand the relationship between petroleum hydrocarbons and soil clays, an artificial soil system is suggested in which the type and amount of soil clay can be controlled.Compaction, kaolinite, petroleum, smectite, tropics, toxicity, water-repellency
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Abstract (Viewed: 5)Cassava root is rich in energy but low in protein. New varieties developed exhibit better nutritional profile. An 8-week experiment was conducted to investigate the effect of dietary supplementation of 2 varieties of cassava root meal (CRM) with various additives on nutrient digestibility energy, metabolizable and carcass traits of broilers. Two hundred and forty unsexed day-old broilers were allotted to 8 dietary treatments in a 2 x 4 factorial arrangement of white (TME 419) and yellow (ITA/IBD/1368) CRM supplemented with no additive, amino acids (methionine and lysine), enzyme and amino acids + enzyme (A.A + Enz). The experiment lasted for the starter (0 - 4 weeks) and finisher (5-8weeks) phases. Variety effect showed higher (p<0.05) nutrient digestibilities in finisher broilers fed with white cassava than yellow. White cassava + amino acids showed higher EED and ASHD while yellow cassava with amino acids + enzyme yielded improved nutrient digestibilities. White cassava variety revealed higher (p<0.05) metabolizable energy values than yellow. Broilers fed white cassava + enzyme had the highest (p<0.05) metabolizable energy values. In conclusion, supplementing yellow CRM with A.A + Enz improved nutrient digestibility only at the starter phase. Supplementation of white cassava diet with enzyme and amino acid at the starter and finisher phases respectively, improved energy metabolizablility.Additives, broilers, carcass, cassava, energy metabolizablility, nutrient digestibility
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Abstract (Viewed: 3)This study assessed the fish community structures and influences of water quality on fish occurrences in Pahang and Tembeling rivers, Pahang. Fish samplings and water quality measurements were conducted in Kuala Mai, Pahang River and Ulu Tembeling, Tembeling River from 12 and eight different sampling points, from October 2007 to September 2008, and August 2006 to August 2007, respectively. The fish diversity, richness and evenness indices were determined, while the water quality parameters were compared for both rivers. Multivariate analyses were then used to explore the effects of water physicochemical parameters on the fish occurrences. A total of 2,391 individuals were collected from this study, comprising of 20 families and 65 species of fish. Using the gill nets, cast nets and fishing rods, a total of 55 fish species from 17 families were recorded in Kuala Mai, Pahang River, compared to 47 species from 15 families in Ulu Tembeling, Tembeling River. There were significant differences (p < 0.05) for fish diversity (H and 1-D), but not for fish evenness (e) and richness (D) between both rivers. The mean water temperature, ammonia nitrogen and total suspended solids were significantly different (p < 0.05) in both rivers. Apart from the influences of pH, alkalinity and phosphate in both rivers, the results showed that the temperature, dissolved oxygen and conductivity were the major influencers on the fish occurrences in Kuala Mai, Pahang River, while ammonia nitrogen and total suspended solids in Ulu Tembeling, Tembeling River. Fish conservation and stock management efforts are urgently needed due to the decreasing number of near-threatened, endangered and critically endangered fish species in both rivers.Community structure, fish ecology, Pahang River, physicochemical parameters, Tembeling River
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Abstract (Viewed: 5)Banana Musa acuminate cv. Berangan is an important fruit crop in Malaysia. The use of tissue culture techniques can increase the number of planting materials for mass production of banana. However, the main problem in banana tissue culture is somaclonal variation, which is caused by many factors, such as long-term subcultures, which can reduce the production value and quality. In this study, the experiment focused on somaclonal variation caused by long-term subculture that had caused changes in their morphology which could be differentiated by RAPD pattern of micropropagated Musa acuminate cv. Berangan plantlets from long-term subcultures (15th subculture). Banana plantlets established from micropropagated banana using MS supplemented with 5 mgL-1 of BAP was maintained until 15th subculture before being hardened and acclimatized in commercial soils. In this experiment, banana seedlings were categorized into four groups based on their heights at 5 - 10 cm, 11 - 15 cm, 16 - 20 cm and 21 - 25 cm. Results showed that the tallest seedlings (21 - 25 cm) produced 9.56 ± 1.01 number of leaves, 218.88 ± 40.89 cm leaf area and 5.32 ± 0.78 cm girth of pseudostem whereby the shortest group (5 - 10 cm) produced 5.67 ± 0.98 leaves, 18.95 ± 12.37 cm of leaf area, and 1.63 ± 0.54 cm girth of pseudostem. RAPD analysis carried out using two primers, OPH09 and OPA15 showed variation between the tallest seedlings and the shortest seedlings. This study concluded that long-term subculture of banana cv. Berangan produced variation in the seedlingś growth thus may affect the quality of planting materials produced.Banana, Berangan, micropropagated, plant height, RAP
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Abstract (Viewed: 4)Heat and high light intensity affected physiology and morphology of young Dipterocarpus alatus Roxb. leaf studied. D. alatus is a native forest tree and being extended to cultivation in the field as an economic crop. Nowadays, climate change due to increasing in temperature and light intensity can affect growth, morphological and photosynthetic traits in D. alatus. This research aimed to study the effects of high temperature and strong light intensity on physiology and morphology of the young D. alatus. The experiment was decided in CRD with 5 replications. The two-year-old D. alatus was treated with combination stress between temperature (at 35°C or 41°C) and light intensity (at 700 or 1800 µmol m-2s-1) for 7 days. Plant morphology, gas exchange, PSII efficiency and photosynthetic pigment contents were measured. Strong light intensity (1800 µmol m-2s-1) affected plant morphology by leaf burning and heat injury. However, high temperature (41°C) combined with strong irradiation enlarged leaf injury and also increased percentage of heat injury (3.01±0.81%; T41L1800) compared to control (0.07±0.00%; T35L700). In contrast, it reduced percentages of leaf angle (-8.77±2.82%) and leaf area (-1.04±0.38%). In addition, the combination stress influenced reduction of net photosynthetic rate and contents of Chl a+b and Chl a but unaffected Chl b and Car contents. Therefore, combined stress affected young D. alatus by damaging photosynthetic pigments such as Chl a and injured leaf tissue. This resulted in reduction in both of photosynthetic mechanism and D. alatus leaf growth. Thus, young D. alatus leaf (two-year-old) was susceptible to heat combined with excessive light.Climate change, Dipterocarpus species, gas exchange, photosynthetic pigment
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Abstract (Viewed: 6)Mitragyna speciose Korth., also known as ketum or kratom, is a tropical plant native to Southeast Asia. Mitragynine is its major active alkaloid. It is traditionally used as treatment for various conditions, including fever. The crude extract of M. speciosa leaves has been proven to have anti-inflammatory and analgesic properties. In general, M. speciosa induces a dose-dependent effect, inducing a stimulant effect at low dose and an opioid-like effect at a high dose. This study was conducted to determine the antipyretic effect of mitragynine and methanolic extract of M. speciosa (MSM) using mice as an in vivo pyretic model. Eighty mice were divided into 8 groups: 6 treatment groups (mitragynine: 5, 10, and 20 mg/kg; MSM: 50, 100, and 200 mg/kg) and 2 control groups (20% Tween 80 in 0.9% NaCl; ketoprofen 1 mg/kg). Eighteen hours after induction of pyrexia by inoculation of yeast, rectal temperature was measured every half an hour for 5 hours. Compared to the negative control group, all groups treated with either mitragynine or MSM had significant reduction of rectal temperature at different points of time. The positive control group treated with ketoprofen had significant (P < 0.001) reduction of pyrexia from 0.5 to 5.0 hours after dosing. At 200 mg/kg, MSM has led to the opioid-like effect of hypothermia, possibly due to its synergistic effect with other compounds such as 7-hydroxymitragynine or mitragynine pseudoindoxyl. This article discusses concerns pertaining to toxicity of mitragynine and MSM, and possible involvement of cyclooxygenase and microsomal prostaglandin E2 synthase pathways. In conclusion, mitragynine and MSM possess dose-dependent antipyretic properties in mice.Mitragyna speciose, mitragynine, mice, pyrexia
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Abstract (Viewed: 15)The milky stork is an endangered waterbird species that is currently being re-introduced in the Kuala Gula Bird Sanctuary, Perak, Malaysia. However, little information is available on the re-introduced populatiońs adaptation and activity especially of that related to foraging. To fill this gap, a new group of re-introduced population released between 2013 and 2014 was followed and studied. During the early release period (January — February 2013), the population incorporated the natural sites (intertidal areas, mudflats, and riverbeds) and also the shrimp farms almost equally as their foraging sites (~50% each). Later (March — May 2013), a shift from the natural foraging sites to the shrimp farms could be observed with increasing visits made to the latter area. However, the storks incorporated the natural sites again between June and August 2013 most notably during their breeding activity. Nonetheless, there was a significant reliance on the newly built shrimp farms (monthly mean visits =17.6 ± 1.26, p = 0.001) and a high percentage of shrimp consumption (30 - 48%) compared to other prey was recorded in the subsequent period (September - June 2014). Furthermore, the principal component analysis (PCA) indicates that the foraging activity of the waterbirds was more likely tied to the area or size of the foraging sites which were heavily influenced by the anthropogenic activity in Kuala Gula. In addition, there is a concern over the prolonged utilization of the shrimp farms and their resource as the milky storks could be exposed to several hazardous pollutants in the long run.Ecology, endangered species, foraging activity, Kuala Gula Bird Sanctuary, milky stork, principal component analysis
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Abstract (Viewed: 8)This paper reports the identification of Streptococcus iniae from a large collection of isolates previously identified as Streptococcus sp., Lactococcus lactis subsp. lactis or Leuconostoc sp. A total of 204 bacterial isolates recovered either from the brain, eye, or kidney of red tilapias in previous disease outbreaks and disease monitoring in Malaysia from 2006 to 2008 were used. PCR identification revealed that 34 (16.7%) of the isolates were confirmed as S. iniae. Our records showed that S. iniae-infected fish exhibited lethargy, exophthalmia, and erratic swimming patterns. Pathological lesions including generalised congestion of the internal organs, splenic infarction with soft and oedematous brain. Histopathological examination revealed multifocal encephalitis as one of the major findings. However, 44% and 26.5% of the tilapias from which S. iniae was isolated did not manifest any clinical sign and pathological lesion, respectively. This study revealed that S. iniae was responsible for streptococcosis in cultured red tilapia in Malaysia since 2006.Oreochromis sp., red tilapia, streptococcosis, Streptococcus iniae