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1.
Differences in gas exchange parameters i.e. carbon exchange rate (CER), transpiration (Tr), water vapor conductance (g) were investigated, under a controlled environment, in a semi-dwarf (SD) Triticum aestivum line, its tall (TL) near isoline and the Payne (PA) variety characterized by small leaves. The plants were maintained in: (a) optimal substrate moisture condition (CTR); (b) salinized by watering with a 0.12 m NaCl solution (SLT); (c) water stressed by withholding waterings during a period of six days (STR); (d) stressed and salinized during the same period and with the same saline solution (S + S). CER and Tr were negatively affected by the stresses; SLT and S + S treatments had a higher WUE compared to their respective controls CTR and STR.
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO2 concentration curves contributed to explaining the SD performance. 相似文献
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO
2.
A field experiment was conducted to find out the critical physiological stages of irrigation schedules inducing better growth, physiological efficiency and seed yield potential of berseem ( Trifolium alexandrinum L., Var. S-99-1). For this purpose eight irrigation treatments were made comprised of four treatments of three irrigation (W1 , W2 , W3 and W4 ), three treatments of four irrigation (W5 , W7 and W8 ) and one treatment of five irrigation (W6 ) at various physiological stages i. e. regeneration, flower initiation, full bloom, seed initiation and advance seed development stage.
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W4 , W1 and W7 ; and further brought out disturbance on the formation of carotene, synthesis of water soluble sugar and translocation of sugar towards reproductive organs during grain development stage. These stresses adversely affected the plant growth and flowering behaviour. The irrigation at seed initiation stage increased the seed yield. Continuous irrigation did not appear to be useful. Thus it can be concluded that irrigation at three critical physiological stages i. e. regeneration, full bloom and seed initiation was found to be essential for obtaining potential seed yield of berseem. 相似文献
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W
3.
Ajai Singh 《Irrigation and Drainage Systems》2008,22(2):179-188
Drip irrigation system has been one of the technical means to improve water use efficiency. In India, this system is gaining
popularity among fruit growers and in water scarced area but a substantial area is being covered annually under vegetables
crops. One of the major concerns raised by farmers about this system is its economic viability. In present study, the economic
viability of drip irrigation system for growing capsicum crop based on discounted cash flow technique (Net present worth and
Benefit cost ratio) was explored. Eight irrigation treatments were laid under drip with and without plastic mulch. The irrigation
levels were taken as 1, 0.8 and 0.6 of the crop evapotranspiration. The pan evaporation method was used for estimation of
reference evapotranspiration and Water Balance Approach was used for irrigation scheduling. The average amount of water supplied
under treatment VD (100% irrigation requirement supplied with drip) was found to be 415 mm for whole growing season of the
crop. Similarly the amount of water was found to be 332 mm and 249 mm for the treatment 0.8VD (80% irrigation requirement
supplied with drip) and 0.6VD (60% irrigation requirement supplied with drip) respectively. Highest yield was recorded in
case of treatment VD + PM (100% irrigation requirement supplied with drip plus plastic mulch) followed by VD. Yield under
treatments 0.8VD, 0.6VD, 0.8VD + PM and 0.6VD + PM were significant while treatments VD, VF and VF + PM were at par with the
treatment VD + PM. Net Present Worth (NPW) was found to be positive for all the treatments. The highest NPW was obtained under
treatment VD as Rs. 309,734.90 and lowest was in case of 0.6VD + PM as Rs. 144,172.24. The yield per mm of water used was
reported to be at higher side as 35 in both the treatments VD and VD + PM. But the yield per mm of water used was found to
be lowest as 18.07 and 19 in case of VF and VF + PM respectively. 相似文献
4.
G. Sahoo T. More V.K. Singh 《Comparative immunology, microbiology and infectious diseases》1998,21(4):319-325
In the present study the level of enzyme hydrolases (alkaline phosphatase, myeloperoxidase, elastase, arginase, lysozyme and β-galactosidase) of polymorphonuclear cell (PMN) granules in different ruminant species and their release in response to activation was studied. Buffalo PMN alkaline phosphatase activity was higher (P < 0.01) than in PMNs of cattle and goats. Interestingly, myeloperoxidase was higher in cattle PMNs and least in goat PMNs (P < 0.01), a similar pattern was observed in the distribution of enzyme arginase. As far as lysozyme is concerned, its activity was significantly higher (P < 0.01) in PMNs of buffaloes than in the case of cattle and goat PMNs. On activation, these cells released MPO and elastase, in all the species studied, while lysozyme was secreted only in buffalo PMN cells. Activity of certain enzymes related to oxidant defence systems such as glutathione peroxidase and glutathione reductase were higher in cattle and goats compared to that in buffaloes. These observations are likely to have bearing on immunodefense roles played by PMNs and reflected differences among the ruminant species studied. 相似文献
5.
Angiography of normal and diseased feet in cattle was carried out. In osteomyelitis of distal phalanx there was a narrowing of the digital artery with diminished vascular supply to the affected digit. An area of bone necrosis was found to be avascular. With overgrown hooves, narrowing of both the medial and lateral digital arteries with ill-defined laminar vessels was seen. The vascular pattern in cattle with cork screw claws was characterized by a dilated tortuous digital artery and a crowded arterial network resulting in increased vascular supply in the affected claw. Abrupt stricture of common digital artery, a crowded vascular network in the area of the middle phalanx and filling defects of terminal arches were demonstrated in animals with exostosis 相似文献
6.
7.
We evaluated a recently developed live vaccine candidate for fowl typhoid (FT)-JOL916, a lon/cpxR mutant of Salmonella Gallinarum (SG)-by comparing its safety and efficacy with that of the well-known rough mutant strain SG9R vaccine in 6-wk-old Hy-Line hens. Forty-five chickens were divided into three groups of 15 chickens each. The chickens were then intramuscularly inoculated with 2 x 10(7) colony-forming units (CFUs) of JOL916 (JOL916 group), 2 x 10(7) CFUs of SG9R (SG9R group), or phosphate-buffered saline (control group). After vaccination, no clinical symptoms were observed in any of the groups. No differences in body weight increase were detected among the three groups postvaccination. A cellular immune response was observed at 2 wk postvaccination (wpv) in the JOL916 group with the peripheral lymphocyte proliferation assay, whereas no response was detected in the SG9R group. Elevation of SG antigen-specific plasma immunoglobulin was observed 2 and 3 wpv in the JOL916 and SG9R vaccine groups, respectively. After virulent challenge on day 25 postvaccination, 0, 1, and 15 chickens in the JOL916 group, SG9R group, and control group, respectively, died by 12 days postchallenge; the death rate of the SG9R vaccine group was statistically similar to that of the JOL916 group. Postmortem examination revealed that the JOL916 vaccine offered more efficient protection than the SG9R vaccine, with significantly decreased hepatic necrotic foci scores, splenic enlargement scores, necrotic foci scores, and recovery of the challenge strain from the spleen. Vaccination with JOL916 appears to be safe and offers better protection than SG9R against FT in chickens. 相似文献
8.
P. Ezhil Praveena Sivakumar Periasamy A.A. Kumar Nem Singh 《Research in veterinary science》2010,89(3):332-339
Mice were experimentally infected with Pasteurella multocida serotype A1 to study the cytokine profiles, host cell apoptosis and sequential pathology at different hours of post-infection. Infected mice were dull, anorectic and depressed. A transient leukocytopenia followed by progressive leukocytosis was observed in the course of infection. Serum cytokine profiles showed significantly (P < 0.01) higher amount of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6 and mouse KC) in the infected mice when compared to control mice. The circulating lymphocytes were apoptotic on annexin V staining. Apoptotic nuclei were detected in splenocytes, hepatocytes and infiltrating leukocytes of the lungs on TUNEL staining. The lungs were grossly congested and hemorrhagic, and showed infiltration with polymorphonuclear cells at early and mononuclear cells in the late hours of infection. Alveolar epithelia, inter-alveolar septa and capillary endothelium of the lungs showed ultrastructural changes. Liver had degenerative changes in histological and ultrathin sections. 相似文献
9.
1. In this study we investigated the residues of fluoroquinolone drugs (ciprofloxacin and pefloxacin) in the cloacal gland (a site of foam synthesis) and other tissues such as breast muscle, testes, brain, kidney and plasma. 2. Fifty-four healthy male Japanese quail were selected at random from a flock, maintained under uniform husbandry conditions and divided into three groups, each of 18 birds. Group I (control) received 1 ml vehicle (normal saline 0.9% (w/v) NaCl) daily for 12 d through the intraperitoneal route. Birds of groups II and III received ciprofloxacin and pefloxacin by the same route at the rate of 10 and 12 mg/kg body weight, respectively, every day for a similar period. 3. Birds from each group were killed, at 1, 5 and 10 d after the cessation of treatment, to collect the cloacal gland together with other tissues that were analysed for residual drugs. 4. Cloacal gland retained the maximum drug residues of ciprofloxacin (60%) and pefloxacin (80%) on d 10 compared with that on d 1 after drug withdrawal. The drug residues were found 60 and 80% in ciprofloxacin and pefloxacin groups, respectively, in the cloacal gland tissue even on d 10 after withdrawal of the treatment. 5. In the ciprofloxacin-treated group, all tissues except cloacal gland contained very small amounts of the drug residues on d 10 after treatment ended. In the pefloxacin group the cloacal gland, breast muscle and kidney retained a fairly high amount of drug even on d 10 after treatment ceased. No residues of pefloxacin were detectable in testes and brain throughout. 6. In conclusion, the cloacal gland in Japanese quail acted as the largest sink for the fluoroquinolone drugs. Ciprofloxacin was more widely distributed in different tissues and persisted for a shorter period than pefloxacin. 相似文献
10.
Singh SK Dimri U Sharma MC Swarup D Sharma B Pandey HO Kumari P 《Veterinary immunology and immunopathology》2011,144(3-4):487-492
The aim of the present study was to evaluate the status of apoptosis in peripheral blood leukocytes of dogs with demodicosis. A total of 26 dogs suffering from demodicosis, and positive for Demodex canis mites by skin scraping, participated in the study, 13 with localized demodicosis (LD) and 13 with generalized demodicosis (GD). A further 13 clinically healthy dogs, all of whom were negative for mites upon skin scraping, were used as controls. The dogs with GD revealed significantly higher (P ≤ 0.0001) percentage of leukocytes with externalization of phosphatidylserine (PS) and depolarized mitochondrial membrane potentials (ΔΨm) as compared with the dogs with LD and healthy controls. These dogs also revealed significantly lower values (P ≤ 0.0001) of hematological parameters viz. hemoglobin, total erythrocytes count total leukocytes count, lymphocytes, monocytes and neutrophils. Significantly higher (P ≤ 0.0001) percentages of leukocytes with externalization of PS and depolarized ΔΨm were also found in dogs with LD as compared with the healthy controls. These dogs also revealed significantly lower values of Hb (P ≤ 0.0001), TEC (P=0.025), TLC (P ≤ 0.0001), lymphocytes (P=0.008), monocytes (P ≤ 0.0001) and neutrophils (P=0.03). It is concluded that premature apoptosis of PBL may be implicated in the immunosuppression of the dogs with demodicosis. 相似文献