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21.
Shaharudin Mohamad Azimi Zaki Noorhariza Mohd Saleh Mohd Nazre Mohd Noor Normah Midin Mohd Razik 《Genetic Resources and Crop Evolution》2022,69(7):2291-2299
Genetic Resources and Crop Evolution - Mangosteen (Garcinia mangostana var. mangostana) is an obligate apomictic species which does not require a fertilization process to produce seeds. The absence... 相似文献
22.
Mohamad Ali Fulazzaky Teng Wee Seong Mohd Idrus Mohd Masirin 《Water, air, and soil pollution》2010,205(1-4):63-77
Water quality degradation in the Selangor River will still be present in the years to come since pollutant loads from poultry farms, municipal wastewaters, and industrial wastewaters are not envisaged to be handled effectively. This will be facing the problems of water quality status to use for multiple purposes and to provide its aquatic environment continuously. The water quality evaluation system is used to assess the water quality condition in the river. This system distinguishes two categories of water condition i.e., the water quality index and water quality aptitude. The assessment of water quality for the Selangor River from nine stations along the main stream, which concludes that water has been highly polluted (index 5) immediately downstream of station 02 Selangor River before confluence with Kubu River due to high concentration of microorganisms and immediately downstream of station 06 Selangor River before confluence with Batang Kali River due to high concentrations of microorganisms and suspended particles, was verified. Mineral micropollutants were found to gradually pollute the stream water, ranging from the unpolluted water (index 1) in the upstream to the bad quality (index 4) in the downstream area. 相似文献
23.
Sayed K. Allameh Fatimah M. Yusoff Hassan M. Daud Einar Ringø Aini Ideris Che R. Saad 《Journal of the World Aquaculture Society》2013,44(6):835-844
This study sought to isolate and characterize lactic acid bacteria (LAB) from stomach of adult snakehead fish, Channa striatus, to be used as probiotics for freshwater fish. A total of 13 strains were isolated from the stomach of 10 fish, and 4 of these belonged to LAB. Strain LAB‐3 showing highest in vitro growth inhibition of Aeromonas hydrophila in a disk diffusion test was identified as Lactobacillus fermentum by conventional and molecular techniques and evaluated in vitro through various tests. The bacterium could grow at pH 3–8; but the optimum growth was observed at pH 6. Moreover, LAB‐3 grew at 0.15 and 0.3% bile salt concentrations, from 15 to 45 C, and at 4% NaCl. L. fermentum showed in vitro inhibitory activity against three fish pathogens, A. hydrophila, Pseudomonas aeruginosa, and Shewanella putrefaciens, tested by disk diffusion and well diffusion methods. Antibiotic sensitivity tests indicated that L. fermentum was resistant to streptomycin, gentamycin, and kanamycin, intermediate to tetracycline, but sensitive to chloramphenicol, amoxicillin, and ampicillin. Challenge test by using A. hydrophila showed that survival of snakehead was significantly (P < 0.05) improved when 2 × 106 LAB‐3/g was supplemented to the diet. Therefore, this study suggests that L. fermentum might be a promising probiotic in snakehead aquaculture . 相似文献
24.
Maryam Aflaki Jalali Hassan Bahrami Sirmandi Abdullah Hatamzadeh 《Journal of Crop Science and Biotechnology》2017,20(1):29-35
Low efficiency of somatic embryo maturation, germination, and conversion to plantlets is a major problem in many species including J. regia L. Germination efficiency of somatic embryos is very low in walnut. In this study, effects of two carbohydrate sources, sucrose and maltose (each at 3% and 6%), and two kinds of PEG (4000 and 6000) (each at four levels of 1.5%, 3%, 5% and 7.5%) on maturation and germination of walnut embryos were tested. The number of somatic embryos increased conspicuously on medium containing PEG. Furthermore, higher levels of PEG-4000 (7.5%) could remarkably enhance the morphogenesis of somatic embryos and the number of embryos produced. PEG-4000 stimulated somatic embryo maturation of walnut. This stimulatory effect was dependent on the carbohydrate source used. Sucrose in combination with PEG-4000 produced 50% of cotyledonary and normal somatic embryos. Different concentrations of PEG were effective on the number of embryos with a shoot meristem. PEG-4000 7.5% and sucrose 3.0% produced the highest rate (50.0%) of normal shooting embryos. However, PEG (4000, 6000) and maltose caused an unfavorable effect and increased the frequency of abnormal shaped somatic embryos. 相似文献
25.
高粗料日粮中添加脂肪对奶年血液代谢产物瘤胃发酵和干物质消化率影响的研究 总被引:2,自引:0,他引:2
对50头泌乳中期的奶牛进行为期6周的饲养试验,研究高粗料高脂肪日粮对奶牛血液代谢产物、瘤胃发酵和干物质消化率的影响。试验设有10个重复,每个重复5头奶牛,每头奶牛给定一种日粮。试验用日粮为:对照日粮(日粮1)和试验日粮(高粗料75%高脂肪7.5%,日粮2;高粗料,中等水平脂肪5.0%,日粮3;中等水平粗料65%,高水平脂肪,日粮4;中等水平粗料和脂肪,日粮5;或者对照日粮中含有50%粗料和2.0%脂肪)。这些日粮含氮量相同(CP17.7%)。粗饲料由20苜蓿干草、40%苜蓿半干青贮和40%青贮玉米组成。所用脂肪由80%瘤胃 保护脂肪和20%黄色油脂组成。试验结果表明:试验组和对照组的血糖浓度差异不显著;试验组的血浆非酯化脂肪酸(NEFA)高于对照组。而奶牛采食日粮的粗饲料和脂肪水平不同,其NEFA差异不显著;对照组、试验组与粗饲料和脂肪水平不同的日粮的瘤胃PH、瘤胃VFA浓度和干物质消化率差异不显著。 相似文献
26.
Kridli RT Momany Shaker M Abdullah AY Muwalla MM 《Tropical animal health and production》2007,39(3):229-235
This study was conducted to evaluate the sexual performance of 10-month-old, ram lambs of different breed groups. Eight ram
lambs each of Awassi (A), F1 Charollais × Awassi (CA) and F1 Romanov × Awassi (RA) breed types were subjected to sexual performance tests by being individually exposed to two oestrous
Awassi ewe lambs for four 20-min periods. Bouts of leg kicking and anogenital sniffing were similar among breed groups. Mounting
frequency was greater (p < 0.05) in RA than in A and CA ram lambs. Tail-raising was greater (p < 0.05) and mating rate tended to be greater (p < 0.10) in A than in RA and CA ram lambs. The number of mounts per tail-raising (efficiency) was influenced by breed group
and test day (p < 0.05). Awassi ram lambs maintained the best efficiency throughout the experiment. Efficiency in RA and CA ram lambs improved
with each test day. Results of the present study indicate that RA ram lambs have greater mounting frequency than A and CA,
while Awassi are more capable of mating with fat-tailed females than the CA and RA ram lambs. 相似文献
27.
Triploid and Hexaploid Regenerants from Hexaploid Timothy (Phleum pratense L.) via Anther Culture 总被引:3,自引:0,他引:3
Pollen embryos were obtained from eight genotypes and viable green plants were regenerated from four genotypes in an anther-culture experiment with 165 genotypes of Phleum pratense L. Formation of proembryos inside the cultured anthers during the first 10—12 days was significantly influenced by genotypes and by the type of nutrient media. Primary embryos developed into multiple secondary embryos before regeneration of plants. Among a total of 62 plants regenerated, only 13 were albinos. Of the green regenerants, 11 were triploid while 35 were hexaploid when DNA-content was measured by flow cytometry. Eight plants with a triploid DNA-content did possess the triploid chromosome number of 21. Triploid and hexaploid regenerants from two different parents showed simplified isozyme (GPI and PGD) banding patterns relative to that of their parents. 相似文献
28.
L. Krishnamurthy Rachid Serraj C. Tom Hash Abdullah J. Dakheel Belum V. S. Reddy 《Euphytica》2007,156(1-2):15-24
Genetic improvement of salt tolerance is of high importance due to the extent and the constant increase in salt affected areas.
Sorghum [Sorghum bicolor (L.) Moench] has been considered relatively more salt tolerant than maize and has the potential as a grain and fodder crop
for salt affected areas. One hundred sorghum genotypes were screened for salinity tolerance in pots containing Alfisol and
initially irrigated with a 250-mM NaCl solution in a randomized block design with three replications. Subsequently 46 selected
genotypes were assessed in a second trial to confirm their responses to salinity. Substantial variation in shoot biomass ratio
was identified among the genotypes. The performance of genotypes was consistent across experiments. Seven salinity tolerant
and ten salinity sensitive genotypes are reported. Relative shoot lengths of seedlings were genetically correlated to the
shoot biomass ratios at all stages of sampling though the relationships were not close enough to use the trait as a selection
criterion. In general, the whole-plant tolerance to salinity resulted in reduced shoot Na+ concentration. The K+/Na+ and Ca2+/Na+ ratios were also positively related to tolerance but with a lesser r
2. Therefore, it is concluded that genotypic diversity exists for salt tolerance biomass production and that Na+ exclusion from the shoot may be a major mechanism involved in that tolerance. 相似文献
29.
30.
Abdelwahab SI Hassan LE Sirat HM Yagi SM Koko WS Mohan S Taha MM Ahmad S Chuen CS Narrima P Rais MM Hadi AH 《Fitoterapia》2011,82(8):1190-1197
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS. 相似文献