Mapping of the quantitative trait locus (QTL) conferring partial resistance to rice leaf blast disease

Malaysian rice, Pongsu Seribu 2, has wide-spectrum resistance against blast disease. Chromosomal locations conferring quantitative resistance were detected by linkage mapping with SSRs and quantitative trait locus (QTL) analysis. For the mapping population, 188 F3 families were derived from a cross between the susceptible cultivar, Mahsuri, and a resistant variety, Pongsu Seribu 2. Partial resistance to leaf blast in the mapping population was assessed. A linkage map covering ten chromosomes and consisting of 63 SSR markers was constructed. 13 QTLs, including 6 putative and 7 putative QTLs, were detected on chromosomes 1, 2, 3, 5, 6, 10, 11 and 12. The resulting phenotypic variation due to a single QTL ranged from 2 to 13 %. These QTLs accounted for approx. 80 % of the total phenotypic variation within the F3 population. Therefore, partial resistance to blast in Pongsu Seribu 2 is due to combined effects of multiple loci with major and minor effects

The Effect of Gamma Radiation on Plant Morphological Characteristics of Zingiber officinale Roscoe

Induced mutation through gamma irradiation can cause changes in chromosome and genome which bring to successful variation in morphology of plant.  The study was carried out to investigate the effect of gamma radiation on mutation frequency and plant morphology of Zingiber officinale Roscoe. The ginger rhizomes of Bentong and Tanjung Sepat cultivars were treated with gamma rays at six different dosages (5, 7, 9, 11, 13 and 15 Gray). The gamma ray was emitted from the Caesium-137 source at the rate of 4.31 Gy per minute at Malaysian Nuclear Agency irradiator facility. Different mutation frequencies and wide of mutation spectrum were observed in all treatments.  The spectrums of mutant characters observed were stunted growth, plant stature, leaf deformation and chlorophyll mutation. The results show that mutation frequency in both varieties was higher at 5 and 7 Gy when compared to other doses. Therefore, the results proved that different doses of mutagen caused different effects on plant

Malaysia-Indonesia cross-border governance: is there a trade-off between security and economic development?

The National Security Council of Malaysia has declared the east coast of Sabah as the Eastern Sabah Security Zone (ESSZONE) to inhibit security threats and enhance security in the east coast of Sabah. This study employed an in-depth interview with the stakeholders involved in security governance and development in the study area. The selection of stakeholders was based on expert sampling. Secondary data relating to maritime economic activities were also used to reinforce the findings of the in-depth interview. The study areas were Tawau (Sabah) and Sebatik Island. Sebatik Island is divided into two regions; the northern region is owned by Malaysia and the south is owned by Indonesia. This paper examined the impact of ESSZONE’s security policy toward economic activities in Tawau and Sebatik Island. The security policy implemented by the Eastern Sabah Security Command (ESSCOM) in Sabah’s east coast has a negative impact on maritime economic activities in Tawau and Pulau Sebatik. Therefore, the government must re-evaluate the security measures in Tawau and Pulau Sebatik waters, and the curfew regulations in particular, because the security threat is lower and more manageable than in Sandakan, Tawau, Kunak, Lahad Datu, Semporna, and Kinabatangan, which form the hot spot area. Furthermore, the government should consider appropriate measures to balance the objectives of security and economic interests, depending on the level of security threat zones

Pengukuran ekonomi sempadan Malaysia - Thailand: Kajian kes Sg. Kolok - Rantau Panjang

Towns along the Malaysia-Thailand border has always been associated with backwardness and low-income regions.This is mainly because policy development in the border regions is based more on defence and security over economic considerations.Economic structures and cross-border trade town of Sg. Kolok and Rantau Panjang are examined with the objective to measure the cross-border economic activity and its impact on the local population, particularly in employment opportunities and poverty eradication.Both towns are a shopping haven among local and foreign tourists and have the potential to become leading cross-border tourism of Malaysia-Thailand border.The Eastern Corridor Economic Region development plan implemented by the Malaysian government and the Southern Border Provinces Special Zone by the Thailand government can sustain cross-border economic development in the future.Security assurance in Southern Thailand will intensify the economic activities in the town of Rantau Panjang and Sg. Kolok.This has spill over effect in the border area by creating economic opportunities,employment and income in both area

Isolated complete popliteus tendon rupture following a trivial occupational injury

Traumatic rupture of the popliteus tendon is a rare type of knee injury. Most reported cases had occurred in athletes or following high impact trauma. We report a case of a 23-year-old male with an isolated complete popliteus tendon rupture that was diagnosed arthroscopically. The patient worked as a general labourer in a sawmill. He fell at his workplace and presented with acute painful fixed flexion of the right knee. Initially he was suspected to have a meniscus tear. Diagnostic arthroscopy of the knee was carried out; and diagnosis of popliteal tendon rupture was established. The patient was subsequently managed conservatively by arthroscopic debridement. He was allowed to mobilize the knee as tolerated after the surgery. He was well with a full knee range of movement and was able to walk normally at six weeks after surgery. This article highlights the possibility of complete popliteus tendon rupture following a minor occupational injury in a previously normal knee

Cloning and analysis of QTL linked to blast disease resistance in Malaysian rice variety Pongsu seribu 2

Blast, caused by Magnoporthe oryzae, is considered to be a global rice disease around the world including Malaysia. Limited information is available on the identification of quantitative trait loci (QTL) and linked markers associated with blast resistance within local rice varieties e.g. Pongsu Seribu 2. Partial resistance against blast disease is widely observed in this variety with mapping of QTLs linked to resistance genes. However, knowledge about the blast resistance genes on chromosome 3 is very limited and no specific blast resistance gene have been identified on chromosome 3 in rice genome of Pongsu Seribu 2. In order to find the similarity of sequence, QTL qRBr-3.1 located on chromosome 3 in Pongsu Seribu 2 was cloned and compared with identified blast resistant genes from other varieties. Sequence analysis of cloned fragment revealed a tandem of (CA)23 repeats. The similarity of sequence was searched in Basic Local Alignment Search Tool (BLAST), which expressed similarity with different clones of rice located on chromosome 3. The cloned QTL fragment also expressed the similarity of 46% with Pi-b, 52% with Pi-kh, 23% with Pi-9 and 38% with Pi-zt, blast resistance genes located at different chromosomes in rice. The QTL fragment produced none of distribution of leucine rich repeats (LRRs) and nucleotide binding site (NBS-LRR). However, the domain contains maximum distribution of leucine amino acid which is responsible for the pathogen recognition in host-plant interaction and play important role in resistance mechanism against diseases. This result concluded that Pongsu Seribu 2 has homology to other resistant genes which are allelic to Pi-b, Pi9, Pi-zt and Pi-kh at different chromosomes

Morphological traits alteration of mutant common turf grass (Cynodon dactylon) induced by gamma ray irradiation

The experiment was conducted to study Cynodon dactylon morphological improvement and breeding by induced mutation using gamma ray irradiation at Universiti Putra Malaysia (UPM) and Malaysian Institute of Nuclear Technology Research (MINT) center. C. dactylon is a widely used turf in Malaysia especially for golf course and football field. However, its coarse leaf texture and long internodes are undesirable for good quality golf field. In this purpose mutagenesis by gamma ray irradiation was employed using 0, 20, 40, 60, 80, 100, 120 and 140 Gy to treat 30 single node stolons per treatment. Dosages of 90 Gy were determined as LD50 for the radio sensitivity test. Survival rate of C. dactylon stolon was greatly reduced when irradiated with higher dosages. This experiment was repeated using LD50 on 1500 single node stolons. Twenty two (22) morphological mutants were identified and evaluated. Most mutants were semi-dwarf type with reduced internode length and leaf blade length. The altered morphological traits were stable after third cutting back (M1V3) shown by their morphological performance. Mutation breeding is effective in improving C. dactylon when easily recognized cultivars are needed

The effect of tualang honey in chronic exposure of high cholesterol diet in animal model

Introduction: Hyperlipidaemia accompanies chronic renal disease either as a consequence of the renal dysfunction or as part of generalized metabolic derangements. The aim of this study was to determine the effects of tualang honey (TH) on the kidneys of animal model with chronic exposure to high cholesterol diet. Materials and method: Twenty Sprague-Dawley rats were divided into two groups, the high cholesterol diet (12% CD (n= 16) and standard diet (SD) (n=4) and were fed for 12 weeks. After 12 weeks, the rats in the 12% CD group were subsequently divided into four groups. The first group was continued with only 12% CD while the other 3 groups in addition to the 12% CD, they were given TH treatment at different concentrations (1.2, 2.4 and 3.0 g/kg/day) for 4 weeks. Biochemical analysis of lipid profile and renal function were performed at the end of the experiment. The animals were sacrificed and the kidneys were harvested for histological examination. Results: In the 12 weeks HCD group, the serum cholesterol, LDL-c and creatinine levels were significantly higher) compared to that of the SD group. All groups with the tualang honey treatment had significant reduction in the LDL-c, triglyceride and creatinine levels. Histological examination of the kidney tissues of the HCD and HCD+TH groups at 16 weeks revealed segmental mesangial proliferation of some glomeruli with focal mesangial matrix expansion. No areas of periglomerular and peritubular fibrosis were observed. Conclusion: Tualang honey supplementation of animal model with chronic exposure to high cholesterol diet improved the renal function hence suggesting the its renoprotective effect. However, there were no changes seen in the histology of the kidneys . Additionally, tualang honey showed improvement in the LDL-c and triglyceride levels indicating its lipid lowering activities

Genetic dissection of rice blast resistance by QTL mapping approach using an F3 population

Rice blast is one of the major fungal diseases that badly reduce rice production in Asia including Malaysia. There is not much information on identification of QTLs as well as linked markers and their association with blast resistance within local rice cultivars. In order to understanding of the genetic control of blast in the F3 families from indica rice cross Pongsu seribu2/Mahsuri, an analysis of quantitative trait loci against one of the highly virulent Malaysian rice blast isolate Magnaporthe oryzae, P5.0 was carried out. Result indicated that partial resistance to this pathotype observed in the present study was controlled by multiple loci or different QTLs. In QTL analysis in F3 progeny fifteen QTLs on chromosomes 1, 2, 3, 5, 6, 11 and 12 for resistance to blast nursery tests was identified. Three of detected QTLs (qRBr-6.1, qRBr-11.4, and qRBr-12.1) had significant threshold (LOD >3) and approved by both IM and CIM methods. Twelve suggestive QTLs, qRBr-1.2, qRBr-2.1, qRBr-4.1, qRBr-5.1, qRBr-6.2, qRBr-6.3, qRBr-8.1, qRBr-10.1, qRBr-10.2, qRBr-11.1, qRBr-11.2 and qRBr-11.3) with Logarithmic of Odds (LOD) <3.0 or LRS <15) were distributed on chromosomes 1, 2, 4, 5, 6, 8, 10, and 11. Most of the QTLs detected using single isolate had the resistant alleles from Pongsu seribu 2 which involved in the resistance in the greenhouse. We found that QTLs detected for deferent traits for the using isolate were frequently located in similar genomic regions. Inheritance study showed among F3 lines resistance segregated in the expected ratio of 15: 1 for resistant to susceptible. The average score for blast resistance measured in the green house was 3.15, 1.98 and 29.95 % for three traits, BLD, BLT and % DLA, respectively