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91.
The effect of a bronchodilator (or ciprenaline sulphate) and intravascular oxygen releaser (sodium dihydrogen orthophosphate) on the host in experimental Dictyocaulus filaria infection was studied. Fifteen male lambs of Dorset-Muzaffarnagri breed, aged 4-6 months, were divided into four groups of four (infected bronchodilator), four (infected i.v. O2 releaser), four (infected untreated controls) and three (uninfected controls). The administration of i.v. O2 releaser helped in increasing the length of useful patency, estimated total larval production and survival rate of D. filaria producer lambs. The administration of I.V. O2 releaser and bronchodilator helped in efficiently restoring the altered values of blood pH, haemoglobin, packed cell volume, erythrocyte sedimentation rate and osmotic fragility of erythrocytes to near normal levels. However, the blood clotting time and level of lactate dehydrogenase activity remained altered and followed a course typical of ovine dictyocauliosis. 相似文献
92.
The clinical signs and gross lesions caused by Eimeria uzura (10(5) oocysts) in Japanese quail (Coturnix coturnix japonica) exhibited little or no influence in the face of intercurrent dietary aflatoxicosis (1 p.p.m. of aflatoxin B1 from Day 0 to 55). Similarly, no significant differences in the mucosal morphology of the intestine were evident histologically between the two groups of Japanese quail. The nervous signs of ataxia, leg weakness, incoordination of movement, torticollis and terminal opisthotonos were toxin-induced manifestations. In the aflatoxic quail, hypoplastic changes and selective depletion of lymphocytes were more prominent in the bursa of fabricius. Increased relative mean weights of liver, kidney, spleen, crop, proventriculus and gizzard were observed in birds due to aflatoxin sensitivity. The combination of E. uzura infection and aflatoxicosis in Japanese quail may cause significant weight loss, and increased oocyst production and reproductive potential. 相似文献
93.
Shot-hole disease of Terminalia paniculata caused by Cylindrocladium quinqueseptatum - a new record1
A shot-hole leaf disease Terminalia paniculata caused by Cylindrocladion quinqueseplatium is reported from Kerala, India. Symptoms of the disease and pathogenicity of the isolate are described. 相似文献
94.
In rural societies of Mizoram, India, traditional methods of treatment are followed in the majority of the populace. Information on 135 plant species from 122 genera and 65 families is presented here. 相似文献
95.
The potential of hedgerow intecrropping with Leucaena leucocephala was explored on vertic Inceptisols over 4 years at ICRISAT Center, Patancheru, India. The study was conducted using a systematic layout involving different alley widths ranging from 1.35 to 4.95 m and with varying distances between hedge and crops. The alleys were cropped with alternate rows of sorghum and pigeonpea. Hedges composed double Leucaena hedgerows 60 cm apart were periodically harvested for fodder. Sole crops of all components and a sorghum/pigeonpea intercrop were included in all four replications of the study.Starting in the second year, Leucaena was progressively more competitive to annual crops, causing substantial yield reduction. Competition (primarily for moisture) was most severe in narrow alleys and was greatest on pigeonpea.The growth of Leucaena was not sufficient to compensate for reduced crop yields. Land equivalent ratios (LERs) calculated on the basis of grain yield of crops and Leucaena fodder yields showed that hedgerow intercropping (HI) was advantageous over sole crops only during the first two years using wide alleys, but disadvantegeous in the last two years. LERs calculated on the basis of total dry matter indicated only a small advantage for HI (13–17 percent) over sole crops in wider (>4 m) alleys. Average returns per year from HI exceeded those of the most productive annual crop system (sorghum/pigeonpea intercropping) by 8 percent in 4.05 m alleys, and by 16 percent in 4.95 m alleys. Fodder production during the dry season was 40 percent of the annual total in these alley widths. Thus hedgerow intercropping at 4–5 m alley width is not very attractive for farmers in semi-arid India, which has 600–700 mm of annual rainfall. There is a need to examine the potential of HI in wider alleys. The merits and limitations of the systematic design are discussed. 相似文献
96.
R. Lal 《Agroforestry Systems》1989,8(2):97-111
Field runoff plots, 70 x 10 m each, were established on a tropical Alifisol in southwestern Nigeria to monitor water runoff,
soil erosion and nutrient loss in water runoff. The non-agroforestry control treatment (A) was established at two levels:
plow-till and no-till systems of seedbed preparation. There were two agroforestry systems based on contour hedgerows of (B)
Leucaena leucocephala and (C) Gliricidia sepium established at 4-m and 2-m spacings. Field plots were established in 1982 and hydrological measurements were made for uniform
maize-cowpea rotation for 12 consecutive growing seasons from 1982 through 1987.
Once established hedgerows of Leucaena at 2-m spacing were extremely effective in reducing water runoff and controlling erosion. Runoff, erosion and nutrient losses
were generally more from maize grown in the first season than from cowpea grown in the second. Mean seasonal erosion from
maize was 4.3, 0.10, 0.57, 0.10, 0.64 and 0.60 t/ha for plow-till, no-till, Leucaena-4m, Leucaena-2m, Gliricidia-2m treatments, respectively. Mean runoff in the first season from treatments listed in the order above was 17.0, 1.3, 4.9,
3.3, 4.3, and 2.4 percent of the rainfall received. There were high losses of Ca and K in water runoff from the plow-till
treatment. In contrast to runoff and erosion, losses of bases in water runoff from agroforestry treatments were relatively
high, high concentration of bases in runoff was probably due to nutrient recycling by the deep-rooted perennials. 相似文献
97.
Development of leaf rust (Melampsora ciliata) in different species, hybrids and cultivars of poplar (Populus spp.) was studied in nursery‐grown plants. Five different criteria were used to assess the disease development. The mean disease index on 10 August was 9.4% which increased to 70.0% on 10 October. The lowest disease index (5.5%) was recorded in P. yunnanensis whereas the maximum was recorded in P. × euramericana‘Rubra‐Poiret’ (59.5%). The apparent infection rate per unit per day was highest in P. nigra × P. trichocarpa (9.7 × 10–2) whereas the minimum occurred in P. maximowiczii × P. berolinensis‘Oxford’ (3.3 × 10–2). The area under the disease progress curve was a maximum in P. × euramericana‘Rubra‐Poiret’ (26.7) and a minimum in P. yunnanensis (1.6). Complete defoliation by the first half of October occurred in P. nigra × P. trichocarpa, which also had the maximum apparent infection rate and area under the disease progress curve. Inoculum production was highest in P. nigra × P. trichocarpa and lowest in P. maximowiczii × P. berolinensis‘Oxford’. 相似文献
98.
Pseudomonas solanacearum (Smith) was consistently isolated from the wilted plants of Casuarina equisetifolia. The isolate gave positive reaction to oxidase, catalase and gas production from nitrate and negative reaction for arginine dihydrolase and acid was produced from various carbohydrates. Wilt produced on tomato, egg plant and capsicum indicated that the pathogen belongs to Race I and Biovar III of P. solanacearum which is a new record from India. 相似文献
99.
V. P. Sharma T. K. Wan G. H. S. Hooper B. Würzer Klara B. Balász J. Bodor 《Journal of pest science》1969,42(1):14-15
Ohne Zusammenfassung 相似文献
100.
A study on dry matter production and nutrient cycling in agroforestry systems of mandarin grown in association with N2-fixing Albizia and mixed tree species (non-N2-fixing) was carried out in the Sikkim Himalaya. A site with Albizia was referred asAlbizia-mandarin stand and the other site with mixed tree species as mandarin stand. The stand total biomass, net primary productivity and mandarin fruit production was higher under the influence of Albizia. Agronomic yield of crops remained nearly the same in both the stands. Nitrogen and phosphorus concentrations of different components of Albizia were higher than those of mixed tree species, whereas their back translocation from leaf to branch before abscission was lower inAlbizia. The mandarin-based agroforestry is a highly nutrient-exhaustive system evaluated in terms of nutrient exit through the removal of agronomic yield. This system, under the influence of Albizia, was more productive with faster rates of nutrient cycling. Nutrient use efficiency increased under the influence of Albizia, in contrary to the hypothesis that efficiency should decrease with increasing rate of uptake. The poor nutrient conservation of Albizia, and malleability of nutrient cycling under its influence make it an excellent association which promotes higher availability and faster cycling of nutrients.Albizia should be utilised more extensively in the management of mandarin-based agroforestry systems. 相似文献