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31.
Deficit irrigation occurrence while maintaining acceptable yield represents a useful trait for sunflower production wherever irrigation water is limited. A 2-year experiment (2003–2004) was conducted at Tal Amara Research Station in the Bekaa Valley of Lebanon to investigate sunflower response to deficit irrigation. In the plots, irrigation was held at early flowering (stage F1), at mid flowering (stage F3.2) and at early seed formation (stage M0) until physiological maturity. Deficit-irrigated treatments were referred to as WS1, WS2 and WS3, respectively, and were compared to a well-irrigated control (C). Reference evapotranspiration (ETrye-grass) and crop evapotranspiration (ETcrop) were measured each in a set of two drainage lysimeters of 2 m × 2 m × 1 m size cultivated with rye grass (Lolium perenne) and sunflower (Helianthus annuus L., cv. Arena). Crop coefficients (Kc) in the different crop growth stages were derived as the ratio (ETcrop/ETrye-grass).

Lysimeter measured crop evapotranspiration (ETcrop) totaled 765 mm in 2003 and 882 mm in 2004 for total irrigation periods of 139 and 131 days, respectively. Daily ETcrop achieved a peak value of 13.0 mm day−1 at flowering time (stage F3.2; 80–90 days after sowing) when LAI was >6.0 m2 m−2. Then ETcrop declined to 6.0 mm day−1 during seed maturity phase. Average Kc values varied from 0.3 at crop establishment (sowing to four-leaf stage), to 0.9 at late crop development (four-leaf stage to terminal bud), to >1.0 at flowering stage (terminal bud to inflorescence visible), then to values <1.0 at seed maturity phase (head pale to physiological maturity). Measured Kc values were close to those reported by the FAO.

Average across years, seed yield at dry basis on the well-irrigated treatment was 5.36 t ha−1. Deficit irrigation at early (WS1) and mid (WS2) flowering stages reduced seed yield by 25% and 14% (P < 0.05), respectively, in comparison with the control. However, deficit irrigation at early seed formation was found to increase slightly seed yield in WS3 treatment (5.50 t ha−1). We concluded that deficit irrigation at early seed formation (stage M0) increased the fraction of assimilate allocation to the head, compensating thus the lower number of seeds per m2 through increased seed weight. In this experiment, while deficit irrigation did not result in any remarkable increase in harvest index (HI), water use efficiency (WUE) was found to vary significantly (P < 0.05) among treatments, where the highest (0.83 kg m−3) and the lowest (0.71 kg m−3) values were obtained from WS3 and WS1 treatments, respectively. Finally, results indicate that irrigation limitation at early flowering (stage F1) and mid flowering (stage F3.2) should be avoided while it can be acceptable at seed formation (stage M0).  相似文献   

32.
Rabies is a zoonotic, fatal and progressive neurological infection caused by rabies virus of the genus Lyssavirus and family Rhabdoviridae. It affects all warm-blooded animals and the disease is prevalent throughout the world and endemic in many countries except in Islands like Australia and Antarctica. Over 60,000 peoples die every year due to rabies, while approximately 15 million people receive rabies post-exposure prophylaxis (PEP) annually. Bite of rabid animals and saliva of infected host are mainly responsible for transmission and wildlife like raccoons, skunks, bats and foxes are main reservoirs for rabies. The incubation period is highly variable from 2 weeks to 6 years (avg. 2–3 months). Though severe neurologic signs and fatal outcome, neuropathological lesions are relatively mild. Rabies virus exploits various mechanisms to evade the host immune responses. Being a major zoonosis, precise and rapid diagnosis is important for early treatment and effective prevention and control measures. Traditional rapid Seller's staining and histopathological methods are still in use for diagnosis of rabies. Direct immunofluoroscent test (dFAT) is gold standard test and most commonly recommended for diagnosis of rabies in fresh brain tissues of dogs by both OIE and WHO. Mouse inoculation test (MIT) and polymerase chain reaction (PCR) are superior and used for routine diagnosis. Vaccination with live attenuated or inactivated viruses, DNA and recombinant vaccines can be done in endemic areas. This review describes in detail about epidemiology, transmission, pathogenesis, advances in diagnosis, vaccination and therapeutic approaches along with appropriate prevention and control strategies.  相似文献   
33.
A total of 207 bovine blood samples were collected from clinically healthy cattle bred in central region of Syria and examined by Giemsa-stained blood smears, nested PCR, ELISA, and IFAT to determine the molecular and serological prevalence of Babesia bovis and B. bigemina. All samples were negative to Babesia spp. by microscopic examination of blood smears. On the other hand, the overall prevalence of B. bovis and B. bigemina was 9.18% and 15.46% by nPCR, 15.46% and 18.84% by ELISA, and 18.36% and 21.74% by IFAT, respectively. Mixed infections were detected in a total of 5 samples (2.4%) by nPCR, 16 (7.73%) by ELISA and 27 (13.04%) by IFAT. Statistically significant differences in the prevalence of the two infections were observed on the basis of age and location. These data provide valuable information regarding the occurrence and epidemiology of B. bovis and B. bigemina infections in Syrian cattle, which can be employed in developing rational strategies for disease control and management.  相似文献   
34.
The physical, molecular, and functional properties of corn, cassava, and yam starches were related to the film properties of these starches. Corn, cassava, and yam starches contained 25%, 19%, and 30% amylose, respectively. Amylose from yam starch showed the smallest molecular weight among the starches and amylopectin from corn starch the smallest molecular weight. Cassava starch presented a higher amylopectin content, and its gels and films were less strong, more transparent, and more flexible than corn and yam films. Plasticized films of the three starches were more flexible, with a higher strain and lower stress at break when the glycerol content increased. Unplasticized films were brittle and had water vapor permeability values ranging from 6.75 x 10(-10) to 8.33 x 10(-10) g m(-1) s(-1) Pa(-1). These values decreased when the glycerol content reached 20 g/100 g of starch because a more compact structure was formed. Then, at a glycerol content of 40 g/100 g of starch, the WVP increased because the film matrixes became less dense.  相似文献   
35.
An extremely large-sized neogrowth of myxoma was observed at the cannon region in a 3-year-old Arabian mare. The mass developed during the course of 4 months. The mass mechanically hindered the animal movement, exposing the mare to multiple external injuries and subsequent blood loss. The clinical parameters, morphology, and hematological and histopathological examinations of the myxoma were recorded. The body condition score of the mare was 1. The hemogram revealed moderate to severe degree of anemia. Histopathological sections assessed after surgical removal identified the mass as a myxoma. To the authors’ knowledge, this is the first report of cutaneous myxoma at equine limb in an Arabian horse.  相似文献   
36.
The pathogenesis of bluetongue (BT) could vary with route of inoculation. Using laboratory-passaged moderately virulent bluetongue virus serotype 23 (BTV-23), one of the most prevalent Indian serotype, we investigated the pathogenesis of BT in intradermally (ID) and intravenously (IV) inoculated native sheep. The ID inoculation resulted in relatively increased clinical signs and lesions in many organs as compared to IV inoculation. BTV-23 detection by real-time RT-PCR and isolation studies revealed that ID inoculation can be more efficient than IV ones in disseminating and spreading virus to systemic organs, including pre-scapular draining lymph node, spleen, lungs and pulmonary artery. Furthermore, the ID inoculation resulted in early onset and increased humoral response with significant increase (P<0.01) in antibody titre at various intervals. Taken together, these data suggest that ID inoculation can be more potent in reproducing many aspects of natural infection, including clinical disease, viral and immune responses, and may be useful route in setting up experimental infections for challenge or pathogenesis studies using laboratory passaged BTVs.  相似文献   
37.
Tropical Animal Health and Production - Bluetongue (BT) is a notifiable multiple species transboundary viral disease of domestic and wild ruminants. Though the disease is enzootic in India, little...  相似文献   
38.
A protocol for in vitro propagation of the wild three-lobed sage (Salvia fruticosa Mill.) (Synonym, Salvia triloba L.) was developed. Shoot tips were excised from in vitro seedlings and established on MS, Nitch and Nitch (NN), or B5 medium. For shoot proliferation, in vitro nodal and apical explants were cultured on MS medium containing 0.25–2 μM 6-benzylaminopurine (BA), 6-furfurylaminopurine (kinetin), or thidiazuron (TDZ). Proliferated microshoots were rooted on MS medium supplemented with 2.7–11.4 μM indole-3-butyric acid (IBA), indole-3-acetic acid (IAA), or α-naphthaleneacetic acid (NAA). Results indicated that shoots established at 100% regardless of media type, however, shoot height, nodes per shoot, and leaf number were highest for explants established on MS medium compared to NN or B5. Number and height of proliferated shoots, nodes per shoot, and leaf number were highest for nodal explants cultured on a medium containing 0.75 μM BA. Microshoots cultured on a medium supplemented with 2.7 μM IBA exhibited the highest rooting percentage compared to those cultured with IAA or NAA. Essential oil composition in microshoots and shoots of greenhouse-grown plants was determined by gas chromatography/mass spectrometry. The major essential oils detected in both plant materials were α-pinene, 1,8-cineole, camphor, and borneol. No α-thujone or β-thujone was detected. The content of essential oils, camphor, and borneol were higher in the microshoots than in shoots of greenhouse-grown plants.  相似文献   
39.
A study was conducted to investigate the protective and therapeutic effects of crude garlic (Allium sativum) against experimental infection with Eimeria stiedae in rabbits. Forty rabbits were divided into four groups of ten rabbits each: a healthy control group (HC); a challenged-garlic-protected group (CGP) which received a daily dose of 0.5 g/kg body weight (bwt) crude garlic for five successive days before challenge with E. stiedae; a challenged-garlic-treated group (CGT) which was treated with a daily dose of 0.5 g/kg bwt crude garlic for five successive days post-challenge; and an infected control group (IC). The challenge dose was 5?×?104 sporulated E. stiedae oocysts per rabbit. Mortality rate, body weight gain, feed conversion ratio and faecal oocyst count were evaluated throughout the experiment. At the end of the experiment, all rabbits were killed and histopathological examination was performed. No mortalities were recorded in the HC and CGP groups, whilst mortality was found to be 20% and 40% in the CGT and IC groups, respectively. CGP rabbits had better body weight gain and lower numbers of oocysts than those in the CGT and IC groups. Hepatic lesions were less severe in the CGP group than in the CGT and IC groups. These results showed that oral administration of crude garlic ameliorated the adverse impacts of hepatic coccidiosis on rabbits when used as a prophylactic, but garlic was less effective as a therapeutic.  相似文献   
40.
The selection of appropriate plant species is critical in the successful application of phytoremediation techniques. The present study is an attempt to assess the capability of three brassicaceae, Brassica alba (L.) Rabenh, Brassica carinata A. Braun and Brassica nigra (L.) Koch, for the phytoextraction of Cr, Cu, Pb and Zn from an unpolluted and polluted silty loamy soil added with either Bacillus licheniformis BLMB1 or compost or both. Experiments were conducted in a greenhouse in pots filled with the soils. In all experiments metals were shown to accumulate in shoots and roots of plants grown on polluted soils, and both compost and B. licheniformis BLMB1 strain were able to enhance the accumulation of metals, especially Cr. In particular, Cr accumulation in B. alba resulted higher than the Cr threshold for hyperaccumulator plants (1000 mg kg? 1). This result provides a new plant resource that may have a potential use for phytoextraction of Cr from contaminated soil. However, because of the low bioconcentration factors (< 1) for all studied metals, these species cannot be regarded as suitable for the phytoextraction of excessive Cr, Cu, Pb and Zn from polluted soils. Thus, these species may be used with success only for low metal polluted soils.  相似文献   
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