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1.
Samit Kumar Nandi Biswanath Kundu Samir Kumar Ghosh Dipak Kumar De Debabrata Basu 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(2):183-191
The present study was undertaken to evaluate porous hydroxyapatite (HAp), the powder of which was prepared by a novel aqueous solution combustion technique, as a bone substitute in healing bone defects in vivo, as assessed by radiologic and histopathologic methods, oxytetracycline labeling, and angiogenic features in Bengal goat. Bone defects were created in the diaphysis of the radius and either not filled (group I) or filled with a HAp strut (group II). The radiologic study in group II showed the presence of unabsorbed implants which acted as a scaffold for new bone growth across the defect, and the quality of healing of the bone defect was almost indistinguishable from the control group, in which the defect was more or less similar, although the newly formed bony tissue was more organized when HAp was used. Histologic methods showed complete normal ossification with development of Haversian canals and well-defined osteoblasts at the periphery in group II, whereas the control group had moderate fibro-collagenization and an adequate amount of marrow material, fat cells, and blood vessels. An oxytetracycline labeling study showed moderate activity of new bone formation with crossing-over of new bone trabeculae along with the presence of resorption cavities in group II, whereas in the control group, the process of new bone formation was active from both ends and the defect site appeared as a homogenous non-fluoroscent area. Angiograms of the animals in the control group showed uniform angiogenesis in the defect site with establishment of trans-transplant angiogenesis, whereas in group II there was complete trans-transplant shunting of blood vessel communication. Porous HAp ceramic prepared by an aqueous combustion technique promoted bone formation over the defect, confirming their biologic osteoconductive property. 相似文献
2.
Vanessa Prigge Raman Babu Biswanath Das M. Hernández Rodriguez Gary N. Atlin Albrecht E. Melchinger 《Euphytica》2012,185(3):453-463
Single crosses (SC) of elite inbreds and open-pollinated populations (OP) are suitable source germplasm for doubled haploid
(DH) line development in hybrid maize breeding, given that they combine a high population mean ([`(x)] \overline{x} ) for testcross performance with adequate response to selection (
\Updelta G \Updelta G ). This is the first study reporting testcross grain yield (TCGY) and dry matter content (TCDMC) evaluations of 131 DH lines
developed from ten tropical source germplasm comprising five OP (OP1–OP5) and five SC (SC1–SC5). Gene diversity (d) and the average number of alleles (a
r
) per locus was estimated for DH lines based on 24 simple sequence repeat markers. Analysis across three environments revealed
no significant differences between [`(x)] \overline{x} of OP- and SC-derived DH lines for TCGY and TCDMC. Significant genetic variance for both traits was only detected among OP-derived
DH lines which may be explained by a larger number of segregating quantitative trait loci (QTL) as suggested by higher d and a
r
values than in SC-derived DH lines. The usefulness criterion (
U = [`(x)] + \Updelta G U = \overline{x} + \Updelta G ) was higher for OP-derived DH lines for TCDMC, but higher for SC-derived DH lines for TCGY. DH lines from OP1, OP2, and OP3
showed high TCGY, suggesting that they may be useful in tropical hybrid breeding. We conclude that tropical OP represent a
valuable source of untapped genetic variation that can efficiently be exploited with DH technology for hybrid maize breeding. 相似文献
3.
Aida Z. Kebede George Mahuku Juan Burgueño Felix San Vicente Jill E. Cairns Biswanath Das Dan Makumbi Cosmos Magorokosho Vanessa S. Windhausen Albrecht E. Melchinger Gary N. Atlin 《Plant Breeding》2013,132(3):299-304
The exchange of elite breeding materials across regions is an important way in which multinational maize breeding programmes access new genetic variation, improve efficiency and reduce costs. Our objectives were to examine whether CIMMYT's breeding programmes for tropical and subtropical environments in Mexico and Eastern and Southern Africa (ESA) can effectively share materials. Sets of selected and unselected lines were evaluated for per se and testcross performance in multiple environments in Mexico and ESA for grain yield, days to anthesis and plant height. Genotypic correlations between performance in Mexico and ESA as testcross and line per se were high (≥ 0.72) for all experiments, and indirect selection efficiency ranged from 67 to over 100% for all traits. Lines selected in ESA or Latin America performed equally well in each region, indicating selection was for broad rather than regional adaptation. Thus, breeding programmes of CIMMYT in both Mexico and ESA can benefit tremendously by exchanging breeding materials and test results, and elite selections from each region should be fast‐tracked for evaluation in the other. 相似文献
4.
Total dry matter (TDM) and nutrient accumulation, nutrient partitioning, and cumulative growing degree days at the time of maximum nutrient accumulation for two‐row spring barley (Hordeum vulgare L.) are not well quantified under high‐yielding irrigated conditions common in the semi‐arid western United States. Thus, five cultivars of barley were grown under irrigated conditions on a loam soil in the 2015 and 2016 growth seasons to determine these factors. Total nutrient accumulation was greatest at either the soft dough or maturity stage where specific nutrients were greater at one stage as compared to the other. Mean N accumulation was greatest at the soft dough stage (256 kg ha?1) where the regression model accounted for 80% of the variation in the data. Additionally, spike N increased from 91 to 105 kg ha?1 from soft dough to maturity. Specific nutrients (e.g., K) had significantly greater plant (i.e., culms plus leaves) accumulation between soft dough and maturity, 253 and 172 kg ha?1, respectively, where the spike at the same growth stages had an accumulation of 37 and 42 kg ha?1, respectively. In contrast, other nutrients (e.g., P) were remobilized to the spike as noted by the increase from 14 kg ha?1 at soft dough to 26 kg ha?1 at maturity. In addition to nutrient partitioning, linear regressions resulted in well‐correlated models between TDM and total nutrient accumulation (R2 = 0.35–0.88) for measured nutrients. Results from the current study provide critical data on nutrient accumulation as well as regression models for two‐row barley under high‐yielding conditions. This information can be used to improve harvest decisions as well as more accurately predict nutrient cycling in barley cropping systems. 相似文献
5.
Combining ability and testcross performance of drought‐tolerant maize inbred lines under stress and non‐stress environments in Kenya 
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下载免费PDF全文 Berhanu T. Ertiro Yoseph Beyene Biswanath Das Stephen Mugo Michael Olsen Sylvester Oikeh Collins Juma Maryke Labuschagne Boddupalli M. Prasanna 《Plant Breeding》2017,136(2):197-205
Drought and poor soil fertility are among the major abiotic stresses affecting maize productivity in sub‐Saharan Africa. Maize breeding efforts at the International Maize and Wheat Improvement Center (CIMMYT) have focused on incorporating drought stress tolerance and nitrogen‐use efficiency (NUE) into tropical maize germplasm. The objectives of this study were to estimate the general combining ability (GCA) and specific combining ability (SCA) of selected maize inbred lines under drought stress (DS), low‐nitrogen (LN) and optimum moisture and nitrogen (optimum) conditions, and to assess the yield potential and stability of experimental hybrids under these management conditions. Forty‐nine experimental three‐way cross hybrids, generated from a 7 × 7 line by tester crosses, and six commercial checks were evaluated across 11 optimum, DS and LN sites in Kenya in 2014 using an alpha lattice design with two replicates per entry at each site. DS reduced both grain yield (GY) and plant height (PH), while anthesis–silking interval (ASI) increased under both DS and LN. Hybrids ‘L4/T2’ and ‘L4/T1’ were found to be superior and stable, while inbreds ‘L4’ and ‘L6’ were good combiners for GY and other secondary traits across sites. Additive variance played a greater role for most traits under the three management conditions, suggesting that further progress in the improvement of these traits should be possible. GY under optimum conditions was positively correlated with GY under both DS and LN conditions, but GY under DS and LN was not correlated. Our results suggest the feasibility for simultaneous improvement in grain yield performance of genotypes under optimum, DS and LN conditions. 相似文献
6.
Ranjan A Sahoo B Singh VK Srivastava S Singh SP Pattanaik AK 《Tropical animal health and production》2012,44(7):1615-1621
The study investigated the effect of dietary supplementation of bypass fat on productive performance and blood biochemical profile of lactating Murrah buffaloes (Bubalus bubalis). Fifteen multiparous buffaloes (2-4 lactation) of early to mid lactation were divided in three homogenous groups T(1) (control), T(2), and T(3) of five each. The animals in T(1) were fed with a basal diet consisting of a concentrate mixture, green sorghum, and wheat straw as per requirements, while the animals in group T(2) and T(3) were fed with same ration supplemented with 0.7 % (100?g/day) and 1.4 % (200?g/day) bypass fat (on dry matter intake (DMI) basis), respectively. The feed intake, milk yield, and milk composition were not influenced by supplemental bypass fat. However, fat-corrected milk (6.5 %) yield was higher (P?相似文献
7.
Information on the effects of phosphorus (P) and sulfur (S) applications on crop response and soil-P status of two-row malt barley (Hordeum vulgare L.) under high-input conditions are limited in alkaline soils despite widespread fertilizer-P and -S use. A field study was conducted during the 2015 and 2016 growing seasons where the barley cultivars (ABI-Voyager and Moravian 69) were grown at five rates of P (0, 37, 73, 110, and 147?kg P ha?1) and three rates of S (0, 112, 224?kg S ha?1). ABI-Voyager had significantly greater biological yield (17,023?kg ha?1) and grain yield (7433?kg ha?1) but a lower (44%) harvest index (HI) than Moravian 69 (15,037?kg ha?1, 7168?kg ha?1 and 49%, respectively). Grain yield increased with rate of P-application until 37?kg P ha?1 where the maximum calculated yield was obtained at 98?kg P ha?1 by a quadratic model. Sulfur application had no significant effect on any of the measured crop or soil parameters. Olsen P increased linearly with greater fertilizer-P applications, indicating grain-P removal was not sufficient to reduce or retain STP concentrations at initial levels when P was applied. Crop-P uptake and soil-P response to fertilizer P applications are important, as remaining soil P is available for subsequent crop usage and may have potential negative environmental impacts. Thus, cultivar selection and appropriate fertilizer-P and S management will ensure optimal agronomic and economic returns while minimizing potentially negative environmental impacts for two-row malt barley produced in the western United States. 相似文献
8.
Raghavendra V. Kulkarni Vaibhav V. Baraskar C. Mallikarjun Setty Biswanath Sa 《Fibers and Polymers》2011,12(3):352-358
Interpenetrating polymer network (IPN) matrices of sodium alginate and carrageenan were prepared for controlled release application.
The propranolol-resin complex (resinate) loaded matrices were prepared by wet granulation/covalent crosslinking method and
subsequently compressed into tablets. The SEM, DSC and XRD studies confirmed the amorphous nature of drug in the IPN matrix
and FTIR confirmed the IPN formation and stability of drug within IPN matrix. The pure drug propranolol HCl showed rapid and
complete dissolution within 60 min, while drug release from resinate was extended for 2.5 h and that from IPN tablets was
still slower and drug release prolonged over 18 h. The crosslinking time of granules affected the release of drug from IPN
matrix. 相似文献
9.
Biswanath Dari Debjani Sihi Santanu Kumar Bal Sanju Kunwar 《Paddy and Water Environment》2017,15(2):395-401
Rice (Oryza sativa L.) is the most important staple food crop in the southern region of Asia, and Indian subcontinent being one of the major producers. Production of conventional transplanted rice requires a large amount of irrigation water, labor, and energy. The scarcity of irrigation water has encouraged farmers to adopt an alternative rice production system, i.e. the direct-seeded rice (DSR), which is proposed to be farmers’ friendly with a potential to save water. Our study reports the performance of DSR with respect to yield and water expense efficiency based on different irrigation regimes and dates of sowing. A field experiment was conducted in the semi-arid region of northern India during the rainy season of 2011 with two treatment combinations (dates of sowing: 15th May and 5th June and three irrigation regimes: irrigation scheduled at irrigation water-to-cumulative potential evapotranspiration; IW/CPE ratio of 1.0, 1.5 and 2.0) in a completely randomized design. We found statistically higher water expense efficiency of DSR sown on 5th June as compared to DSR sown on 15th May without any significant differences in growth and yield. A significant yield difference between DSR grown with irrigation regimes of IW/CPE 1.0 and 1.5 and DSR grown with irrigation regimes of IW/CPE ratio 2.0 were observed. The DSR grown with irrigation regimes of IW/CPE ratio of 1.5 resulted in significantly higher water expense efficiency than the one with IW/CPE ratio of 2.0. Obtaining a higher yield of DSR under scarce irrigation water might be a trade-off between optimum water use and maximum yield avoiding excess ground water exploitation in sub-tropical semi-arid regions of India. Our study suggests that sowing time and irrigation regimes are two important aspects of “rice production” to attain “win–win” solution. Thus, strategic and judicial use of irrigation water with management of sowing time could potentially escalate the rice production in water scarce regions of India. 相似文献
10.
This study was exclusively conducted to evaluate healing of surgically created defects on the radius of adult Black Bengal goat after implantation of porous bioglass blocks and compare the process kinetics with normal healing. Twelve Black Bengal goats were divided randomly into two groups: control and experimental group implanted with bioglass blocks. Unicortical bone defects in radius were generated in all animals under aseptic condition. Local inflammatory reaction and healing of wound, radiological investigations, histological studies, oxytetracycline leveling and angiographic studies were performed up to 90th day post-operatively and compared with normal healing. It has been found that extensive new bone formation originating from host bone towards the implant whereas in control, the process was active from both the ends; the defect site appeared as homogenous nonfluorescent area. Thus, porous bioglass promoted bone formation over the entire extension of the defect independent of size of block in comparison to control group. 相似文献