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1.
M. Akhlasur Rahman Isaac Kofi Bimpong J. B. Bizimana Evangeline D. Pascual Marydee Arceta B. P. Mallikarjuna Swamy Faty Diaw M. Sazzadur Rahman R. K. Singh 《Rice》2017,10(1):47
Background
Salinity is one of the most severe and widespread abiotic stresses that affect rice production. The identification of major-effect quantitative trait loci (QTLs) for traits related to salinity tolerance and understanding of QTL × environment interactions (QEIs) can help in more precise and faster development of salinity-tolerant rice varieties through marker-assisted breeding. Recombinant inbred lines (RILs) derived from IR29/Hasawi (a novel source of salinity) were screened for salinity tolerance in the IRRI phytotron in the Philippines (E1) and in two other diverse environments in Senegal (E2) and Tanzania (E3). QTLs were mapped for traits related to salinity tolerance at the seedling stage.Results
The RILs were genotyped using 194 polymorphic SNPs (single nucleotide polymorphisms). After removing segregation distortion markers (SDM), a total of 145 and 135 SNPs were used to construct a genetic linkage map with a length of 1655 and 1662 cM, with an average marker density of 11.4 cM in E1 and 12.3 cM in E2 and E3, respectively. A total of 34 QTLs were identified on 10 chromosomes for five traits using ICIM-ADD and segregation distortion locus (SDL) mapping (IM-ADD) under salinity stress across environments. Eight major genomic regions on chromosome 1 between 170 and 175 cM (qSES1.3, qSES1.4, qSL1.2, qSL1.3, qRL1.1, qRL1.2, qFWsht1.2, qDWsht1.2), chromosome 4 at 32 cM (qSES4.1, qFWsht4.2, qDWsht4.2), chromosome 6 at 115 cM (qFWsht6.1, qDWsht6.1), chromosome 8 at 105 cM (qFWsht8.1, qDWsht8.1), and chromosome 12 at 78 cM (qFWsht12.1, qDWsht12.1) have co-localized QTLs for the multiple traits that might be governing seedling stage salinity tolerance through multiple traits in different phenotyping environments, thus suggesting these as hot spots for tolerance of salinity. Forty-nine and 30 significant pair-wise epistatic interactions were detected between QTL-linked and QTL-unlinked regions using single-environment and multi-environment analyses.Conclusions
The identification of genomic regions for salinity tolerance in the RILs showed that Hasawi possesses alleles that are novel for salinity tolerance. The common regions for the multiple QTLs across environments as co-localized regions on chromosomes 1, 4, 6, 8, and 12 could be due to linkage or pleiotropic effect, which might be helpful for multiple QTL introgression for marker-assisted breeding programs to improve the salinity tolerance of adaptive and popular but otherwise salinity-sensitive rice varieties.2.
S. A. Selim K. M. S. Aziz A. J. Sarker H. Rahman 《Veterinary research communications》1991,15(4):327-333
Faecal samples from 434 calves under 1 year of age (307 diarrhoeal and 127 normal) were collected from three dairy farms and one village in selected areas of Bangladesh. The samples were tested by an enzyme-linked immunosorbent assay (ELISA) to detect the presence of rotavirus antigen. Of 402 dairy calves tested, 28 (7.0%) were positive, of which 21 (7.2%) were from diarrhoeic calves and 7 (6.3%) from non-diarrhoeic calves. Rotavirus infection varied from farm to farm (2.7–9.2%) and there was no positive response from any of the 32 village calves. Rotavirus was most commonly found in calves of 1 week of age or less (up to 22.2% in one group) but was not found in any calves later than 6 months of age. More than 80% of rotavirus-positive samples from diarrhoeic calves exhibited a titre of 128 or more (geometric mean 345±4.5), whereas non-diarrhoeal calves had titres less than or equal to 128 (geometric mean=29±1.9), suggesting that rotavirus infection in calves in Bangladesh was mostly associated with diarrhoea. 相似文献
3.
Howard A. Clonts Curtis M. Jolly Syed Abdulkadir L. Alsagoff 《Journal of the World Aquaculture Society》1989,20(4):268-276
The merits of integrated aquaculture farming (IAF) as a strategy for bolstering income for the rural poor have been recognized, but the economic efficiency and sustainability are yet to be determined. The effects of one species on another and the economic benefits, net of government support, have not been critically evaluated. The concept of a foodniche for alternative species in an aquatic environment has not been properly tested in an economic setting. Thus, this report reflects the results of applying the technique of mixed integer linear programming to determine the optimum combination of species within the context of a foodniche. The objective also included maximizing revenues, with minimal external input requirements, for a representative small Malaysian wet-rice farm. It was found that the foodniche concept permitted flexibility in stocking rates, and that farmers could actually stock species at the exact rate that was optimal for profit, instead of standard fixed rates. Also, government subsidies for pond construction were essential for IAF success. The net revenues from IAF were low without interest-free loans for pond construction. 相似文献
4.
5.
银杏幼胚离体培养再生植株的研究 总被引:5,自引:0,他引:5
以佛手银杏幼胚为外植体, 研究了不同大小幼胚在不同培养条件下, 愈伤组织和胚状体的诱导发育情况。结果表明: 大于3 mm的幼胚, 在MK +NAA 1.0 mg·L - 1 +BA 1.0 mg·L - 1培养基上胚状体诱导率最高, 达到53.6% , 最多的一块愈伤组织形成多达38个胚状体。暗培养不利于胚状体的发生。在MK培养基上添加10%椰汁对胚状体的生长发育有很好的促进作用, 有34.5%生长成苗。 相似文献
6.
Balamurugan Vinayagamurthy Alamuri Anusha Bharathkumar K. Patil Sharanagouda Siddanagouda Govindaraj Gurrappa Naidu Nagalingam Mohandoss Krishnamoorthy Paramanandham Rahman Habibur Shome Bibek Ranjan 《Tropical animal health and production》2018,50(5):1131-1138
Tropical Animal Health and Production - In this study, the seroprevalence and distribution of Leptospira in dairy cattle in endemic states of India were investigated in association with... 相似文献
7.
T. A. A. Nasrin M. A. Rahman M. A. Hossain M. N. Islam M. S. Arfin 《The Journal of Horticultural Science and Biotechnology》2017,92(6):598-605
Strawberries (Fragaria × ananassa Duch.) were coated either with chitosan (1, 1.5, and 2% solution, w/v) or aloe vera (AV) gel and the coatings were air dried. Coated strawberries were put in a polypropylene box and stored in refrigerator (6 ± 1°C and 50 ± 5% relative humidity. The success of coating in retaining the postharvest quality of the strawberries was evaluated by determining respiration rate, firmness, weight loss, external colour change, ascorbic acid content, total soluble solids, acidity, pH, microbial decay and sensory quality. The incidence of microbial rot started on day-6 in uncoated and 1% chitosan coated strawberries. Strawberries coated with 1.5 and 2% chitosan were affected by microbial decay on day-9 of storage. On the other hand, rot incidence was initiated in AV gel coated strawberries on day-15 of storage. Aloe vera gel or chitosan coating reduced respiration rate, weight loss, and microbial decay and preserved firmness, ascorbic acid content, and other quality parameters, thus delaying ripening and the progress of fruit decay due to senescence or microbial attack. Furthermore, AV gel delayed the changes in external colour and retained all other postharvest quality of strawberries compared to chitosan coated or uncoated ones throughout the storage. 相似文献
8.
Yadav Sudhir Mondal Manoranjan K. Shew Aaron Jagadish S. V. Krishna Khan Zahirul Haque Sutradhar Asish Bhandari Humnath Humphreys Elizabeth Bhattacharya Jayanta Parvin Rokhsana Rahman Mahabubur Chandna Parvesh 《Paddy and Water Environment》2020,18(2):331-343
Paddy and Water Environment - Most of the lands of the southern coastal zone of Bangladesh are protected from tidal flooding and storm surges by embankments constructed during the 1960s and 1970s,... 相似文献
9.
Yoo-Jin Park Ki-Jin Kwon Won-Hee Song Won-Ki Pang Do-Yeal Ryu Md Saidur Rahman Myung-Geol Pang 《Reproduction in domestic animals》2021,56(2):333-341
In this study, we tried to optimize the porcine semen extender conditions to maximize the differences between live X chromosome-bearing (X) spermatozoa and to Y chromosome-bearing (Y) spermatozoa without a decline in the fertility rate at different pH conditions during storage. We observed the viability of X and Y boar spermatozoa in acidic (pH 6.2), original (pH 7.2), and alkaline condition (pH 8.2) for 5 days to investigate the effect of storage conditions on the X to Y spermatozoa ratio. The functional parameters of spermatozoa were also examined to evaluate sperm quality. Sperm motility was preserved at pH 7.2 and pH 6.2 for 3 days, while sperm motility at pH 8.2 decreased significantly after 2 days. Non-capacitated spermatozoa increased while capacitated spermatozoa decreased during storage. Sperm viability decreased significantly duration-dependent under all pH conditions, but there was no significant difference during storage at pH 6.2 and 7.2. The X: Y ratio of live spermatozoa in acidic condition was maximized (1.2:1) without affecting the sperm function and fertility-related protein expression after 2 days compared to original conditions. Moreover, insemination of sows using acidic extender increased the number of female pups on days 1 and 2 of preservation. These results indicate that the production of female offspring may increase when acidic BTS is used for 2 days without affecting the success rate of AI. Above all, this method is simple and economical compared to other methods. 相似文献
10.
Mohammad Mijanur Rahman Khairiyah Mat Genki Ishigaki Ryo Akashi 《Animal Science Journal》2021,92(1):e13594
Year by year, huge quantities of by-products are generated during the manufacturing process of soybean-based products. Okara is one of the by-products, and it is an insoluble portion of the soybean. It consists of high moisture (8.4–22.9%); on dry matter basis, it contains high metabolizable energy (9.0–14.2 MJ/kg) and other components that include crude protein (20.9–39.1%), crude fiber (12.2–61.3%), crude fat (4.9–21.5%), and ash (3.4–5.3%). Fermentation of okara improves its nutritional quality and reduces its anti-nutrient contents. Due to animals' palatability, okara can be used to replace the soybean meal/concentrate feed partially or completely in ruminant's diet and partially in nonruminant's diet. Okara feeding does not depress the intake, digestibility, growth, milk production, blood metabolic profiles, and meat quality of animals. However, this by-product decays quickly due to its high moisture content, and its heavy weight and sticky nature make it difficult to process and expensive to dry using conventional methods. This paper thoroughly summarizes the utilization of okara as animal feed in the cause of developing a general guideline with favorable levels of inclusion in the diets of animals for its exploitation and valorization. This review will encourage further research to develop eco-friendly and value added feed for animals. 相似文献