Isolation of Plant Hormone (Indole-3-Acetic Acid - IAA) Producing Rhizobacteria and Study on Their Effects on Maize Seedling

18 rhizobacteria were isolated from various rhizospheric soils in Mandalay region, Myanmar and some of their biochemical characteristics were studied. Among them, 4 isolates belonged to Bacillus spp. and another 5 strains were recognized as Serratia spp. All 18 isolates were screened for indole-3-acetic acid (IAA) production and quantitative determination of IAA was done for all strains by UV-Vis spectrophotometer with 2 days interval during 10 days incubation. All isolates had different optimum IAA production periods and strain R1 was the best IAA producer strain with 121.1 ppm. It was observed that Bacillus spp. produced IAA ranging from 53.1 ppm to 71.1 ppm optimally and Serratia spp. can be regarded as poor IAA producer strains. Among these 18 strains, four of the best IAA producers (R1, R3, R5, R8) were selected for further study on maize plant and their activities of nitrogen fixation were also detected by plate screening method. Seed germination rate was studied with eight types of treatment and the treatment systems with isolates cannot show distinct positive effect on seed germination rate. At 20th day after sowing, dry root weight and fresh root weight, root length, number of adventitious roots, dry shoot weight and fresh shoot weight and shoot height were measured. In pot trial experiment, treatment R1 significantly increased the fresh shoot weight, shoot height and dry shoot weight whereas treatment R3 significantly increased fresh root weight, root length, dry root weight and number of adventitious roots and all treatments with bacterial isolates showed plant growth promotion than the control systems

Development of Leucaena Mimosine-Degrading Bacteria in the Rumen of Sheep in Myanmar

Myanmar has an agricultural base, and about 70% of people reside in rural areas. They depend for survival on agriculture and small-scale crop production, with ruminant livestock consuming fibrous agricultural residues. For optimal ruminant production, concentrates are needed as supplements to these residues. As concentrates are expensive, researchers are testing alternative protein sources like legumes, including foliage from leguminous trees such as leucaena (Leucaena leucocephala). Leucaena is the most widely used leguminous tree as a ruminant feed because it is rich in protein (~ 22%) and contains easily digestible fibre (23% neutral detergent fibre, 16.6% acid detergent fibre; Ni Ni Maw 2004). Khin Htay Myint (2005) noted that 25% of leucaena in the ration tended to increase nitrogen retention without decreasing dry matter and organic matter digestibilities. However, leucaena leaves contain a toxic non-protein amino acid, called mimosine. Research workers have endeavoured to reduce mimosine toxicity in animals fed leucaena in Myanmar (Aung Aung 2007, Wink Phyo Thu 2010) and one avenue of research was the development of mimosine-degrading bacteria in the rumen of sheep fed leucaena. In this paper we describe an experiment tracing the development of mimosine-degrading bacteria in the rumen of sheep

Experimental modal analysis of vehicle exhaust system to determine hanger location using root mean square value

Vibration of exhaust system due to the engine operation and the condition of the road surface which is transferable to the body through the hanger affects the noise, vibration and harshness performance of the vehicle, and the life time of the hangers. In order to solve this problem of the automobile exhaust system, experimental modal analysis was carried out by utilizing a sample exhaust system of passenger car as a research object within the frequency of interest. LMS Test. Lab was used to perform modal analysis. This study estimated the dynamic characteristics of the exhaust system such as natural frequencies and mode shapes. Using frequency response function at every measuring point, root mean square value (RMS) of vibrating energy was calculated to select hanger location of exhaust system where the RMS value is comparatively small. Experimental modal analysis is an efficient tool to study and estimate the dynamic properties of the exhaust system, and calculating RMS value is also an easy method to find hanger location of the exhaust system utilizing frequency response function

Experimental verification of parameters in automobile crankshaft modelling for vibration analysis

In the interest of utilized more stable automobile components at high speed for reduction the vibration of mechanical system, dynamic characteristics analysis plays a vital role in complex mechanical parts. This paper introduces a clarified approach on statistical investigation and modal analysis methodology to study, predict and accurate crankshaft natural frequencies by using design of experiment (DOE). In this research, first, simulation had been done with MSC Nastran/ Patran to find out the natural frequencies in each mode shape of crankshaft as well as the verification with experiment was carried out. In order to less inaccuracy, numerous simplified crankshaft models were created by using these as input and DOE was established to acquire precise parameters of optimized crankshaft design as the second phase. This method can be further used for the optimizing the structural parameters and would provide some value basis to qualitative measure of parameters and determination of optimized structure. In Conclusion, modal verification accuracy between experimental and simulation has improved

Investigation of mirror-like surface finish in optical glass (BK7) lapping

Surface quality of optical glass is crucial for application in high precision products. This paper aim to investigate the surface roughness improvement and the limit surface roughness of the BK7 optical glass for mirror-like surface finish. Due to the brittleness of workpiece, lapping pressure need to be controlled diligently to prevent crack and brittle fracture from occurring. At first, the new lapping tool is installed on the collect chuck of the CNC milling machine and lapping is performed by the table movement in X and Y direction by NC control. Then, suitable lapping parameters are carefully selected for ductile mode machining in mirror-like finishing process. According to results, the mirror-like surface is achievd with proposed lapping method especially in low lapping pressure of 25MPa

Evaluation of Tropical Herbaceous Legumes for Drought Resistance in Myanmar

Animal nutrition systems in the tropical and subtropical countries utilize a wide range of feedstuffs, mainly the crops and agricultural by-products, grasses, legumes, trees and shrubs. During the dry season, the crude protein concentration in the native grasses can drop below 3% crude protein (Atta-Krah and Reynolds, 1989). Fodder tree is not sufficient and is of low quality in Myanmar (Myo and Aye, 2007). Shrubs represent an enormous potential source of protein for ruminants in the tropics (Devendra, 1992). Browses are rich in nitrogen and minerals which are low in other conventional feeds of tropical regions. Herbaceous legume species play an important role in feeding ruminants worldwide. Herbaceous forage legume have been identified as potential protein supplements for ruminants since they contain high crude protein, minerals and vitamins needed for the growth of ruminal microbes (Norton and Poppi,1995). Herbaceous legumes can be grown as a relay within cereal crops or as a rotation with cereals. Herbaceous legumes can access ‎atmospheric ‎N‎ (‘fixation’)‎ through‎ bacterial‎ activity‎ in‎ root ‎nodules.‎ The‎ ‘fixed’ ‎N‎ becomes‎ available ‎to‎ the‎ legume and subsequent cereal crops. Herbaceous legumes are best planted from seed (Nulik et al., 2013). The aim of using herbaceous legumes in cropping systems is to increase animal productivity, particularly live weight gain in animals being prepared for market. Herbaceous legumes may be fed directly to animals as fresh material in the late wet and early dry seasons, with browse or tree legumes retained for later dry season feeding, or stored as hay and fed in the late dry or early wet seasons when the availability and quality of local feed is lower (Nulik et al., 2013). Legume based pastures give high individual animal performance for growth, fattening, reproduction and wool growth. Cattle live weight gain has been related positively to the proportion of legume in the sward (Mureithi et al., 1995). As pastures become mature, they are characterized by high content of fibre with a higher grade of lignifications and low protein content (Enoh et al., 2005). In Myanmar there is only 0.35% cultivated pasture area to that of cultivated acreages. The improvement and development of pasture is a necessity for Myanmar (Myo and Aye, 2007). For that reason it is needed to evaluate the yield herbaceous legumes for the potential use for ruminants in Myanmar

Selection of Suitable Varieties of Grasses for Myanmar

The basal feed resources for ruminants available in most developing countries in the tropics are crop residues, pasture from infertile land, for example communal land, or agro-industrial by-products. These are low in protein and of low digestibility. A major problem facing livestock producers in tropical areas is proper nutrition for their animals during the dry season when pastures, cereal residues and maize stover are limiting in nutritional quality. The researchers in Myanmar have tried to improve the nutritive value of fibrous agricultural residues. Aung Aung et al. (2006) supplemented the sesame and chickpea husk to bulls fed on urea-treated rice straw. One way of improving the utilisation of such crop residues is by proper supplementation with leguminous forages (Poppi and McLennan 1995). In most regions of Myanmar, the green forage is available during the rainfall and become shortage during dry season. Therefore, feedstuff for ruminant animals mainly has to depend upon the availability of agricultural by-products. Almost more than half of the livestock population of Myanmar is inhabited in dry zone and thus, to overcome the scarcity of the feedstuff during summer, the irrigation system was introduced in these areas for the development of agriculture. A simple and effective way to increase livestock production is to grow improved pastures. Throughout Myanmar, extensive areas of idle land could grow excellent pasture. At present, most of the “pastures” consist of low rank, poor quality grasses and a limited range of edible shrubs. During prolonged dry periods, grazing animals subsist on dry mature roughage of poor quality (Myo Kywe and Tin Mg Aye, 2007). Grass species, which can rapidly grow after the rain also having drought tolerance, would be very useful in the production system. There is still little information on the use of forage in Myanmar. It is needed to select the grass species which have drought resistance in Myanmar and thus this experiment was conducted to evaluate a range of introduced tropical grasses in the central dry zone of Myanmar

Comparisons on the nutritive values of local and introduced forages and feed mixture for ruminant feed in central dry zone of Myanmar

This study aimed to compare nutritive values of local (Sorghum) and introduced (Mombasa) forages and their feed mixtures for ruminant feed in central dry zone of Myanmar. Sorghum based feed mixtures (FeedMix-1, 2 and 3) were the commonly used feed mixtures for cattle in dry zone of Myanmar and other feed mixtures (FeedMix-4, 5 and 6) were based on Mombasa. The lower CP and higher fibre contents (P<0.05) were observed in sorghum and its feed mixtures. The highest gas volumes (P<0.05) were observed in the FeedMix-4 and 6, and then the lowest gas volume (P<0.05) was observed in FeedMix-3. The gas production from quickly soluble fraction (a) of sorghum was significantly higher (P<0.05) than that of Mombasa, inversely the gas production from insoluble fraction (b) of sorghum was significantly lower (P<0.05) than that of Mombasa. Moreover, potential gas production (a+b), ME, OMD and SCFA of sorghum were also significantly lower (P<0.05) than those of Mombasa. The value of “a” was lowest (P<0.05) in FeedMix-1, whereas the highest value was found in FeedMix-6. The lowest values (P<0.05) of “b”, “a+b”, ME, OMD and SCFA were observed in FeedMix-3 and the highest values (P<0.05) of those parameters were found in FeedMix-4. Thus, the higher nutritive values observed in the introduced forage, Mombasa and its feed mixtures were indicating that Mombasa should be used instead of sorghum for the feed of cattle in dry zone of Myanmar.&nbsp

Evaluation on dry forage yields and nutritional characteristics of introduced herbaceous legumes in Myanmar

The study was carried out to evaluate the forage yields, nutritive values and in vitro fermentation parameters of herbaceous legumes. Five varieties of introduced herbaceous legumes; Stylosanthes guianensis cv. Ubon stylo, Macrotyloma axillare cv. Archer, Centrosema brasilianum cv. Ooloo, Stylosanthes guianensis cv. Stylo 184 and Macroptilum bracteatum cv. Cadarga were evaluated at the research farm, University of Veterinary Science, Yezin, Myanmar. No fertilizer and no irrigation were applied for cultivation to test drought resistance. Dry forage yield, nutritive values and gas production at four harvesting times were measured with 4×5 factorial arrangement (5 legumes and 4 harvesting time) in randomized complete block design. There was no interaction between legumes and harvesting time on forage yield, nutritive values and fermentation parameters but they were affected by the main effects of legume types and harvesting time. Among the legume forages, the highest dry forage yields were found in Ooloo, Ubon stylo, and Stylo 184, and followed by the DM yield of Archer and Cadarga. The DM yield of the second harvest was significantly higher (p<0.05) than those of the first, third and fourth harvest which were not significantly different from each other. As a chemical composition, the DM content of Archer was lower (p<0.05) than those of other varieties. Among the legumes forages, the lower CP content was found in Cadarga. The higher NDF was observed in Ooloo. Ooloo, Ubon stylo and Cadarga showed higher ADF in comparison with the other two varieties. Among the harvesting time, the lowest DM content was found at the first harvest. The highest CP content was found at third harvest. The NDF content was not significantly different. The lowest ADF content was found in fourth harvest. According to the dry forage yield, Ubon stylo and Ooloo had the highest dry forage yield and in term of nutritive values, Stylo 184 and Archer had higher nutritive values. As the main effect of forages, Stylo 184 and Archer had higher gas production in comparison with the other varieties. As the main effect of harvesting time, the fourth harvest had the highest gas production in comparison with other harvesting time. It could be better for cultivation by application of fertilizer and irrigation to get more forage yield and quality. &nbsp

Bioactive compounds screening, antimicrobial activities of leave extract from two palatable plants: Piper betle and Murraya koenigii (Curry leaves)

Introduction: Piper betle Linn is one of the most commonly used compounding plants for ethno-medical purposes, with its extract generally used in modern products to enrich their functional efficacy. The extraction methods always lead to differences in the antimicrobial efficacy of methanol extracts of bioactive compounds. Purpose: The study was conducted to screen for bioactive compounds and determine their antimicrobial efficacy in a methanol extract of Piper betle and Murraya koenigi leaves from five different regions. Methodology: The phytochemical screening done according to the procedure that is implied in from Patil, et.al, with minor modifications by the researchers of the current study. Antimicrobial activity was determined; efficacy was measured by disc diffusion analysis. Results: Phytochemical screening revealed the presence of saponin, tannin, terpenoids, alkaloids and flavonoids in the extracts. The methanolic extract of betel leaves from all the selected regions except from Bau exhibited antimicrobial activities. Among them, extract from Kuching and Simunjan have no effect on E. coli. The methanolic extract of curry leaves from Kuching, Balai ringai and Bau have antimicrobial activities against Staph aureus and those from Balai ringai is also active against E.coli. Conclusion: Although there were previous reports of phytochemical screening and antimicrobial activities from the extract of these plants, there were still lack of research conducted on the specimens especially from our local community (Sarawak). The outcome of this study will help us to identify the bioactive compounds of the local samples and give us some pictures of their activities on how to ensure these plants can be brought forward based on the origin of the sample. KEYWORDS: Bioactive Compounds Screening, Antimicrobial Activities of Leave Extract, Palatable Plants, Piper betle and Murraya koenigii