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1.
ABSTRACT

Rice-Wheat rotation is the dominant land use in the state of Punjab, resulting in over exploitation of ground water resources. Thus, it is necessary to evaluate other land uses that requires less water and are sustainable. The present investigation was planned with four land uses viz., fallow (FLU), rice-wheat (ALU), grasses (GLU) and pear (PLU) with respect to their effect on soil organic carbon and soil physical characteristics in surface and subsurface depth in district Ludhiana, Punjab. The soil organic carbon (SOC) content was higher by 10, 30.9 and 24.9% under rice-wheat, grasses, and pear than that under fallow. The grasses showed higher soil moisture characteristics curve (SMCC) and lower bulk density (Db) than that under rice-wheat. The larger mean weight diameter (MWD) were observed under pear, grasses and fallow than that under rice-wheat by 0.21, 0.51 and 0.41 mm, respectively. The saturated hydraulic conductivity (Ks) was higher in magnitude by 56.1, 55.4 and 28%, respectively under PLU, GLU and FLU over ALU. Of the evaluated land uses, pear and grasses proved to be more sustainable by retaining more moisture, maintaining better soil physical characteristics and SOC under semiarid irrigated conditions in the state on long term gradual response.  相似文献   
2.
Cucumber Mosaic Virus, or Infectious Chlorosis, was found in alarming proportions in all the districts of Tamil Nadu on the ‘Robusta’ (Dwarf Cavendish) and ‘Poovan’ (Mysore) cultivais. The disease was transmitted only through suckers from the diseased gardens. Among the genotypes screened, the clones with ABB genomes showed complete field resistance.  相似文献   
3.
1. The effect of probiotic supplementation on egg production, on serum and yolk cholesterol and on egg shell thickness in 24 White Leghorn layers was studied from 28–38 weeks of age.

2. In 3 treatments the diet was supplemented with 0, 100 and 150 mg probiotic/kg food.

3. In the 100 mg probiotic group, egg production improved by 5%, and shell thickness improved slightly, with fewer thin‐shelled eggs than in the control (8.6% compared to 18.6%).

4. The initial serum cholesterol concentration of 170.2 mg/dl in control birds remained similar throughout the 10‐week experimental period, whereas in the 150 mg group the initial value of 176.5 mg/dl decreased to 114.3 mg by week 10.

5. Yolk cholesterol concentration was 14.69 mg in the control group and 11.28 and 11.37 mg/g in the 100 and 150 mg probiotic groups respectively. Overall mean total egg cholesterol was thus reduced by probiotic supplementation.  相似文献   

4.
5.
Abstract

Strawberry shoot meristem cultures have been used for producing virus-free strawberry plants. Plantlet regneration from leaf mesophyll protoplasts, and Agrobacterium tumefaciens mediated genetic transformation, mark the beginning of strawberry improvement with biotechnologies. The use of biotechnological tools has a greater potential in producing strawberry plants with traits such as early maturation, frost and disease resistance, mite and nematode resistance, high yield, better quality, suitability for mechanical harvesting, shipping ability, ellgaic acid content, aroma compounds and cost-effective micropropagation. Gene identification and mapping with RFLPs or RAPDs would be desirable. Transgenic strawberries should be tested for their quality before releasing to the consumers.  相似文献   
6.
A new leaf spot disease of banana(Musa sp.) cv. ‘Rasthali’ (syn. Silk) was observed in Tamil Nadu, in 1987. The causal organism was isolated in pure culture and identified asRhizoctonia solarii Kühn. The teleomorphic stage,Thanatephorus cucumeris (Frank) Donk, has also been induced artificially. This is the first record of this pathogen causing leaf spot disease onMusa sp. The pathogenicity of basidiospores on several other important crops was also tested.  相似文献   
7.
We report isolation of a strain of fermentative coryneform bacteria from an outbreak of polyarthritis in chickens. This strain could not be assigned to any recognized bacterial taxon because its peculiar phenotype is not yet reported. The strain possessed phenotypic characteristics and fatty acid profile similar to Erysipelothrix but, on the other hand, exhibited temperature-dependent motility like Listeria. We found no evidence of either Mycoplasma synoviae or Chlamydia infection. Details of the phenotype and fatty acid profile of the isolate and measures undertaken to contain the outbreak have been described.  相似文献   
8.
Pasteurella multocida is isolated from a variety of disease conditions from different animal species in our diagnostic laboratory. In order to determine serogroup distribution among the isolates, an indirect haemagglutination test using glutaraldehyde-fixed sheep red blood cells was employed. A serological examination of 79 isolates revealed that 47/79 were of capsular serogroup A, 11/79 capsular serogroup D, 4/79 capsular serogroup B and 17/79 were untypable strains. None of the isolates belonged to either serogroup E or F. All those from cases of classical pasteurellosis could be grouped, but a significantly high proportion of those which originated from companion animals were untypable. The significance of these results is discussed. This report appears to be the first detailed information on the prevalence of various serogroups of P. multocida in animals in southern Africa.  相似文献   
9.
Pasteurella gallinarum-related outbreaks in chickens and African guinea fowls are described. Four outbreaks were recorded in chickens and one in guinea fowls. Periorbital swelling and keratoconjunctivitis were the consistently present clinical signs in all the diseased birds. In several, swollen hocks and wattles were also discerened. Birds which succumbed to the infection showed petechiation in the internal organs and evidence of airsacculitis. Pasteurella gallinarum was isolated from the lesions and also from conjunctival swabs of the apparently healthy in-contact birds. There was no evidence of concurrent infection with Haemophilus, Mycoplasma or Chlamydia. Quinolone therapy when resorted to on one of the farms resolved the clinical signs. Phenotypes of 28 isolates were studied. The results compared well with the Pasteurella gallinarum isolates reported earlier from elsewhere. It was also found that results of xylose fermentation and ONPG test appear to be a variable character. There is no earlier report of P. gallinarum infection in guinea fowls.  相似文献   
10.
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