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Five tomato cultivars, ‘Pusa Ruby’, ‘Chico Grande’, ‘Sugar Gimar’, ‘Italian Red Pear’ and ‘Roma’, their F1 hybrids, back crosses and F2 progeny, were evaluated for fruit-quality and canning-behaviour.The fruits of ‘Pusa Ruby’ were many-loculed, thin fleshed, flat-to-round and soft with good flesh colour, while the others were few-loculed, thick fleshed, oval-to-pear shaped and firm, with poor flesh colour. Fruits from the F1 generations of the crosses between the two types were intermediate in a majority of the above characteristics. Cut-out tests and evaluation of canned tomatoes revealed that ‘Roma’ and the F1 and back-crosses to both parents of ‘Pusa Ruby’ × ‘Chico Grande’, and the F1 of ‘Pusa Ruby’ × ‘Italian Red Pear’ were suitable for whole-fruit canning. The F1s of ‘Pusa Ruby’ × ‘Chico Grande’, which out-yielded all others, hold promise as the best material for canning.  相似文献   
23.
The intake rate of the local Vertisol is very low (0.08 cm/h). Vertical mulch was used from 1971 to 1976 in order to improve infiltration. Higher moisture contents were recorded near the mulch. The favourable effects of mulch extended to 1.5 m on either side of the mulch row. Vertical mulching exerted a greater influence on crop yields under dry conditions than in normal and above normal seasons. Compared with low yields in control plots (grain: 0.2 q/ha (20 kg/ha); straw: 9.5 q/ha (950 kg/ha)) mulches spaced at 2, 4 and 8 m produced 3.9 q/ha of grain and 19.0 q/ha of straw under the extremely dry conditions of 1972–1973. However, the increase in grain and straw yields under wet conditions in 1973–1974 was only 47.2 and 15.0%, respectively. Averaged over dry and wet years, vertical mulching resulted in 45.1 and 37.9% higher grain and straw yields. The favourable effects of vertical mulching were found to last for 4 years. Considering dry and wet years, a spacing of 4 m was found to be ideal. Placing sorghum stubble as a vertical mulch to the top of the salt zone (30 cm) was found to be as good as placing it to a depth of 90 cm.  相似文献   
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1. Laying performance, egg quality, fertility and hatchability, and fat deposition in liver and abdomen were recorded in broiler breeders (29 to 48 weeks of age) fed on diets containing perarl millet (Pennisetum typhoides) (PM), broken rice (BR) or yellow maize (YM) (600 g/kg diet). Constant ratios of metabolisable energy (ME) to other nutrients were maintained in all the diets. Food grade choline chloride (50%) was added to the diets at 3 concentrations (0, 760 and 1,520 mg/kg). Each diet was offered to 3 replicate groups of 15 birds (12 hens and 3 cockerels), maintained in deep litter pens, to provide 1.46 MJ ME/bird/d. 2. Neither the source of energy nor dietary choline content had any influence on hen-d egg production, fertility or hatchability. Food efficiency and egg weight were significantly reduced in BR-fed groups compared to those fed on the other energy sources. 3. The efficiency of energy and protein utilisation increased and liver fat content was decreased significantly by dietary choline supplementation. 4. Haugh unit score, egg shell weight, liver weight and intestinal weight were not influenced by either supplementary choline or the source of energy. However, the yolk colour index was significantly reduced in PM- or BR-fed groups compared to those fed on the maize-based diet. 5. Deposition of abdominal fat was significantly greater in BR-fed birds compared to those fed on the YM-based diet, while liver fat content was significantly greater in the birds fed on the PM-or BR-based diets than those based on YM. Although supplementation of the diet with choline had no influence on abdominal fat deposition, liver fat content was significantly reduced in birds given diet containing 760 mg supplemental choline/kg diet. 6. The present study indicates that PM or BR can be used as principal energy sources in place of YM in broiler breeder diets without affecting egg production, fertility or hatchability. Liver fat content can be reduced by adding choline at 760 mg/kg to diets based on different energy sources.  相似文献   
26.
1. The relative utilisation of different phosphorus sources in relation to their fluorine (F) content was studied in commercial broilers (5 to 40 d) and White Leghorn layers (252 to 364 d). The phosphorus (P) sources tested were bonemeal (BM), low fluorine (LFRP) and high fluorine (HFRP) rock phosphates and a commercial mineral mixture (CMM). The P sources were incorporated in broiler and layer diets by replacing dicalcium phosphate (DCP) on a P basis. 2. The F contents of diets based on BM, LFRP, CMM and HFRP were 53, 365, 622 and 1383 mg/kg in the broiler experiment and 34, 242, 437 and 967 mg/kg in the layer experiment, respectively. F was not detected in DCP based diets. 3. In broilers, body weight gain, food intake, gain: food, P retention and serum inorganic P content on P sources (BM and LFRP) containing F up to 365 mg/kg diet were similar to those on DCP. Body weight gain, food intake, serum calcium and inorganic P contents and retention of P were depressed in groups fed on CMM and HFRP, which may have been due to the toxic effects of F (622 and 1383 mg/kg) present in diets based on these P sources. 4. Bone ash and its P content were not affected by feeding diets containing F up to 1383 mg/kg from various P sources. The amount of F deposited in tibia increased significantly with increases in dietary F concentration. 5. In layers, egg production and food intake were not affected by F up to 437 mg/kg in diets containing BM, LFRP or CMM as the sole source of supplemental P. Egg production and food intake were depressed significantly in layers given the diet containing 967 mg F/kg from HFRP. 6. Egg mass: food, egg weight, shell quality (shell thickness and shell weight) and serum calcium and inorganic P levels were not affected by F up to 967 mg/kg in diets containing different P sources. 7. It may be concluded that the performance of broilers and layers was not affected by feeding various P supplements with dietary levels of F up to 365 and 437 mg/kg, respectively. The reduced performance in broilers and layers observed with some of the P sources may have been due to poor availability of P and/or toxic effects of F (622 and 967 mg/kg, respectively).  相似文献   
27.

Background

The pathogenesis of caseonecrotic lesions developing in lungs and joints of calves infected with Mycoplasma bovis is not clear and attempts to prevent M. bovis-induced disease by vaccines have been largely unsuccessful. In this investigation, joint samples from 4 calves, i.e. 2 vaccinated and 2 non-vaccinated, of a vaccination experiment with intraarticular challenge were examined. The aim was to characterize the histopathological findings, the phenotypes of inflammatory cells, the expression of class II major histocompatibility complex (MHC class II) molecules, and the expression of markers for nitritative stress, i.e. inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT), in synovial membrane samples from these calves. Furthermore, the samples were examined for M. bovis antigens including variable surface protein (Vsp) antigens and M. bovis organisms by cultivation techniques.

Results

The inoculated joints of all 4 calves had caseonecrotic and inflammatory lesions. Necrotic foci were demarcated by phagocytic cells, i.e. macrophages and neutrophilic granulocytes, and by T and B lymphocytes. The presence of M. bovis antigens in necrotic tissue lesions was associated with expression of iNOS and NT by macrophages. Only single macrophages demarcating the necrotic foci were positive for MHC class II. Microbiological results revealed that M. bovis had spread to approximately 27% of the non-inoculated joints. Differences in extent or severity between the lesions in samples from vaccinated and non-vaccinated animals were not seen.

Conclusions

The results suggest that nitritative injury, as in pneumonic lung tissue of M. bovis-infected calves, is involved in the development of caseonecrotic joint lesions. Only single macrophages were positive for MHC class II indicating down-regulation of antigen-presenting mechanisms possibly caused by local production of iNOS and NO by infiltrating macrophages.  相似文献   
28.
Thermochemistry and aqueous solubilities of hydrotalcite-like solids   总被引:1,自引:0,他引:1  
Hydrotalcites are used in technology as catalysts and anion exchangers and are important sinks for environmental contaminants. Their compositional variability makes it important, but difficult, to estimate their aqueous solubility. We report calorimetric measurements of the heats of formation of cobalt-aluminum hydrotalcite phases. The heat and free energy of formation from the elements are equal to those of mechanical mixtures of binary compounds, namely hydroxides and carbonates. The interlayer anion is much more important than the cation in determining the solubility of the hydrotalcite phase and its ability to contain or release heavy metals to the environment. Because hydrotalcites do not have an unreactive polymer as a structural core, their aqueous stability will change dramatically with composition, particularly with anion content. This simple mechanical mixture model allows prediction of aqueous solubilities and trace metal retention in a variety of geochemical settings.  相似文献   
29.
In the context of a growing interest in remote sensing for precision agriculture applications, the utility of space-borne hyperspectral imaging for the development of a crop-specific spectral library and automatic identification and classification of three cultivars for each of rice (Oryza sativa L.), chilli (Capsicum annuum L.), sugarcane (Saccharum officinarum L.) and cotton (Gossipium hirsutum L.) crops have been investigated in this study. The classification of crops at cultivar level using two spectral libraries developed using hyperspectral reflectance data at canopy scale (in-situ hyperspectral measurements) and at pixel scale (Hyperion data) has shown promising results with 86.5 and 88.8% overall classification accuracy, respectively. This observation highlights the possible integration of in-situ hyperspectral measurements with space-borne hyperspectral remote sensing data for automatic identification and discrimination of various crop cultivars. However, considerable spectral similarity is observed between cultivars of rice and sugarcane crops which may pose problems in the accurate identification of various crop cultivars.  相似文献   
30.
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