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71.
Abstract

To harness the benefits of system of rice intensification (SRI) coupled with short-duration rice-hybrids, 10 multi-location “On-Farm-Trials” were conducted during 2007–2012 in Himachal Pradesh, India. The study revealed that rice-hybrids were more productive with higher resource-use-efficiency than high-yielding-varieties (HYVs) both under conventional-transplanting (CT) and SRI. The Arize-6129 rice-hybrid exhibited wider adaptability for CT and SRI under varying bio-physical regimes. Arize-6129 rice-hybrid under SRI in rainfed medium-fertility, irrigated medium-fertility and irrigated high-fertility situations yielded about 6.75–6.88, 7.00–7.86, and 7.58-8.32 t grains ha?1, respectively; with respective net returns of INR 48,517–49,761, 57,240–62,603 and 64,333–66,748?ha?1. After Arize-6129, “Swift,” “US-312,” and “PAC-801” are the alternate options for SRI-cultivation. Adoption of SRI using short-duration rice-hybrids under participator-mode technology-transfer program, led to higher net income gains by 29.4% over CT in study area. Overall, SRI using short-duration rice-hybrids has provided new opportunities to enhance rice productivity and profitability to transform rural-livelihoods in wet-temperate NW Himalayas.  相似文献   
72.
The identification of suitable crop varieties that respond best to organic management is the key to achieving better crop yields. A field experiment was conducted during the winter season of 2005–2006 and 2006–2007 at Almora (Indian Himalayas) to evaluate the performance of five varieties of garden pea (Pisum sativum L.) and changes in the soil properties under organic and integrated nutrient management (INM) systems. The yield reduction under organic management was 14.4% in 2005–2006 and 10.1% in 2006–2007 compared with INM. Among the garden pea varieties ‘Vivek Matar 9’, ‘Vivek Matar 8’ and ‘Azad pea 1’ produced similar but significantly higher pod yield compared to other varieties. The soil pH, organic carbon, and microbial activities in terms of dehydrogenase and phosphatase (acid and alkaline) were higher in the plots under organic management compared to INM. The latter, however, had higher activity of urease, and N, P, and K contents in soil. We conclude that at least 15–20% price premium for organic garden pea may be required to offset the higher cost of cultivation and low yields under organic production system. Among the garden pea varieties, ‘Azad pea 1’, ‘Vivek Matar 8’ and ‘Vivek Matar 9’ were found suitable for organic cultivation.  相似文献   
73.
The aim of the present study was to evaluate acellular dermal matrix (ADM) of rat origin for the repair of ventral hernia in horses. The skin from rats, to be used as a graft, was de-epithelialized using hypertonic solution and further decellularized with 0.5% sodium dodecyl sulfate and 0.25% tri-(n-butyl)-phosphate. Under general anesthesia, the hernial ring was exposed and repaired with the ADM graft using inlay graft technique. Blood samples were collected at postimplantation days 0, 15, and 30 and were used for sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis to assess the serum protein concentration of the animals, as well as for gelatin zymography for the identification of matrix metalloproteinases. All animals had an uneventful recovery without clinical signs of wound dehiscence, infection, or recurrence of hernias during 6-month follow-up period. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of concentration of the serum proteins revealed that this was increased at day 15 and had decreased again at day 30. Gelatin zymography showed only one major band of 92 kDa in the serum of all the horses with the implant, but the relative amount of 92 kDa was higher at day 15 as compared with day 0 and day 30. It may be concluded that ADM of rat origin can be used safely in horses for repair of ventral hernia.  相似文献   
74.
The study was conducted to investigate the effect of phosphorus (P) concentrations (0, 5, 10, 20, 50, and 100 μg g−1) on growth and arbuscular mycorrhizal (AM) colonization of two crops (a rainy season crop, Phaseolus mungo Roxb. var. PU-35 and a winter crop, Triticum aestivum L. var. WH-147) and seedlings of two multipurpose tree species (Eucalyptus tereticornis Sm. [Clone C-7, ITC, Bhadrachalam] and Albizia procera Benth.). Plant growth parameters (shoot length, dry weight) and P uptake increased significantly after inoculations with AM fungi (Acaulospora scrobiculata Trappe, Glomus cerebriforme McGee, and Glomus intraradices Schenck and Smith) in P. mungo, T. aestivum, E. tereticornis, and A. procera. Best results were obtained with G. cerebriforme in P. mungo and A. procera, and A. scrobiculata in T. aestivum, and G. intraradices in E. tereticornis. Results on effect of P application on mycorrhizal dependency (MD) of studied crop and tree species showed that decrease in MD with increase in P concentrations in non-nitrogen-fixing species (T. aestivum and E. tereticornis) was higher than in nitrogen-fixing species (P. mungo and A. procera). Threshold P concentrations for maximum benefits from the AM symbiosis in above-mentioned plant species varied from 5 to 20 μg g−1 and corresponding peaks of arbuscules, vesicles, sporocarp formation, colonization index, and spore count per 100 g sand were noticed. Thus, the results showed that the recorded plant growth peaks were due to AM colonization of crops and tree rhizosphere. Inoculations with AMF were more important than P application (explaining 14–78% variation in plant growth) for P. mungo, T. aestivum, and A. procera (forward selection method), whereas P application was more important for growth in E. tereticornis. Therefore, inoculating plants with a suitable AM inoculant could result in a benefit comparable to high P input and lead to a significant saving of inorganic P fertilizer.  相似文献   
75.
Inheritance and segregation at five microsatellite loci were studied in diploid gynogenetic and triploid backcross progenies obtained from koi × goldfish hybrid females, which produce diploid eggs. Gynogenetic and backcross progenies were obtained from three individual hybrid females by inseminating eggs with genetically inactivated and intact sperm of parental species respectively; no shock treatments were applied to the early embryos. Complete absence of paternally specific alleles at all investigated microsatellite loci has proven successful genetic inactivation of spermatozoa by irradiation and confirmed gynogenetic origin of progenies. Genotypic segregations at microsatellite loci showed almost complete homogeneity of gynogenetic progenies and their identity to female parents. These results correspond with previous cytogenetic data on the occurrence of premeiotic endomitosis in hybrid females producing diploid eggs. Fish from triploid backcross progenies had genotypes resulting from combination of entire diploid female genome and haploid genome from male.  相似文献   
76.
Maize is categorized as a salt-sensitive crop and identification of fairly salt-tolerant lines is of paramount importance for increasing its production on saline soils. Experiments were conducted in randomized block design with three replications to identify maize accessions showing response to saline water irrigation, traits imparting tolerance, and their effect on yield attributes of maize. Significant variation was present among genotypes for specific leaf area (SLA), potassium (K) content, cob characteristics, yield, biomass, and harvest index. High amount of heritability with large genetic advance indicated the presence of additive gene action for traits like leaf water potential and leaf dry weight. Association analysis revealed high correlation between key traits and direct as well as positive effect of these traits on yield. Principal component analysis resolved three principal components, and high leaf area and water potential were conferring salt tolerance and thus higher yield.  相似文献   
77.
Heterogeneous amniotic fluid contains various cell types. The aim of this study was to characterize and differentiate some of the key stemness attributes of the amniotic fluid-derived cells in buffalo (Bubalus bubalis). The amniotic fluid (AF) cells were cultured without feeder cells, in DMEM containing 15% FBS, 1% non-essential amino acids, 1% penicillin/streptomycin/ampicillin, 1% vitamin solution, and 1% l-glutamine in 5% CO(2) in humidified air at 38.5±0.5 °C. After 6 days of culture different types of cells viz., star shaped (62.7%), spherical without nucleus (1.9%), spherical with nucleus (26.4%), pentagonal (0.4%), and free floating/rounded cells (8.3%) were observed. Most of the cells started anchorage-dependent growth after day 7 of the culture. Expression of alkaline phosphatase (AP) and Oct-4, Nestin and FGF-5 were observed from the AF cells at different passages. Using species-specific primers, a PCR amplicon of 200, 296 and 210 bp were observed for Oct-4, Nestin and FGF-5, respectively. The cells were found to have a normal karyotype at different passages. These results may contribute towards establishing non-embryonic pluripotent stem cells for various therapeutic and reproductive biotechnological applications in the species.  相似文献   
78.
Thirty-two water buffalo (Bubalus bubalis) calves aged 6?C10?months were used to evaluate serological responses to Brucella abortus strain RB51 (RB51) vaccination in a dose?Cresponse study and to compare the use of two selective media for the isolation of RB51. The animals were randomly divided into three treatment groups. Groups I?CIII received the recommended vaccine dose (RD) twice 4?weeks apart, RD twice 18?weeks apart and saline once, respectively. Lymph nodes were excised from the three groups and subjected to bacteriological examination to determine the frequency of detection of RB51. Pre- and post-vaccination blood samples were collected and tested for B. abortus antibodies using the buffered plate agglutination test (BPAT), complement fixation test (CFT), and dot-blot assay. Sera taken at all post-inoculation weeks (PIW) were negative for field strain B. abortus using the BPAT. Antibody responses to RB51 were demonstrated in all vaccinates but not in controls by CFT and dot-blot assay from 1 PIW up to 16?weeks following booster vaccination. The agreement for both assays was 80.7% and there was a linear interdependence with a Pearson??s correlation coefficient value of 0.578. The frequency of isolation of RB51 from the two selective media used was not significantly different (P?>?0.05).  相似文献   
79.
80.
The segmentation of symptoms during image analysis of diseased plant leaves is an essential process for detection and classification of diseases. However, there are challenges involved in the task, many of them related to the variability of image and host/symptom characteristics and conditions. As a result of those challenges, the methods proposed in the literature so far focus on a specific problem and are usually bounded by tight constraints regarding image capture conditions. This research explores a new automatic method for segmenting disease symptoms on plant leaves that was designed to be applicable in a wide range of situations. The proposed technique employs only color channel manipulations and Boolean operations applied on binary masks, thus being simpler and more robust compared to many previously described automatic methods. Its effectiveness is demonstrated by tests performed over a large database containing images of 77 different diseases of 11 plant species. A comparison with manual segmentation is also presented, further reinforcing the advantages of the proposed approach.  相似文献   
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