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101.
102.
Selenium (Se) is an essential micronutrient for humans and animals, and also affects plant metabolism. In this study, the effects of increasing doses of Se application on the uptake of selenium (Se), nitrogen (N), and sulfur (S) content of three barley cultivars were investigated. The analysis indicated that the Se contents were highest in root tissues, intermediate in grain, and lowest in stem tissues in all cultivars. Total Se accumulations (whole plant) were highest in ‘Bülbül 89’ (0.171 mg kg?1), intermediate in ‘Çetin 2000’ (0.153 mg kg?1), and lowest in ‘Tarm 92’ cultivars (0.124 mg kg?1). In all cultivars, the increase in grain Se content resulted in a decrease in the grain N content. While ‘Bülbül 89’ can be suggested for biofortification purposes, less Se accumulating ‘Tarm 92’ cultivar can be suggested as a fodder in Se contaminated or high Se containing areas.  相似文献   
103.
ABSTRACT

Silicon (Si) provides extra strength to plants against lodging. A hydroponic study was conducted to compare Si requirements of three high yielding, nitrogen (N) responsive, coarse varieties of rice (KSK-133, PK-3717-12, and IRRI-6) with four low yielding, lodging susceptible, fine varieties of rice (BAS-191, BAS-385, BAS-370, and PK-3300). Two-week-old uniform seedlings were grown in half strength Johnson's nutrient solution containing 0, 25, 75, and 150 mg Si kg? 1 as sodium silicate. The plants were allowed to grow for 45 days after transplanting. Silicon application significantly (P ≤ 0.01) increased root and shoot dry matter production in all the rice varieties. The maximum shoot dry matter production occurred at 75 mg Si kg?1 and decreased uniformly in all the rice varieties at 150 mg Si kg? 1. However, growth response to Si application varied significantly (P ≤ 0.01) among various rice varieties. Root: shoot growth ratio, varying from 0.11 to 0.15, did not follow any trend. Different rice varieties and Si addition had a significant (P ≤ 0.01) main and interactive effect on concentration and total uptake of Si in rice root and shoot. Relative increases in Si content, both in shoot and root, were gradual and several fold with increasing rates of Si application. The effect was more pronounced in Basmati varieties (BAS-198, BAS-385, and BAS-370) than other varieties. A 0.91 mg Si g? 1 plant tissue was optimum for growth of KSK-133 (coarse), which was significantly higher than the optimum level, 0.62 mg Si g? 1 plant tissue, for Bas-370 (fine). However, further verification of the results is warranted under field situation.  相似文献   
104.
Productive characteristics and body measurements of Norduz goats, a native genetic resource in Turkey, were measured. The animals studied were brought from natural habitats to the farm of the Animal Science Department of Agricultural Faculty, Yüzüncü Yıl University. Least squares means of withers height (WH), body length (BL), chest width at back of withers (CWBW), chest depth (CD), chest girth (CG) and leg girth (LG) of Norduz does were 65.9 ± 1.08, 67.2 ± 1.08, 21.1 ± 0.88, 30.8 ± 0.62, 88.9 ± 1.78 and 60.4 ± 1.28 cm, respectively. Least squares means of body weights after parturition of does were 41.3 ± 2.01 kg. The means of lactation length and lactation milk yield were 226. ± 7.2 days and 347 ± 40.1, respectively. Twinning rate, fertility, fecundity, litter size and litter size at weaning were 30%, 98%, 1.27, 1.30 and 1.28, respectively. Means of WH, BL, CWBW, CD, CG, LG and body weights of Norduz bucks were 73.9 ± 2.61, 75.6 ± 2.23, 21.4 ± 0.67, 33.9 ± 1.15, 95.0 ± 2.34, 69.8 ± 2.69 cm and 58.7 ± 3.91 kg, respectively.  相似文献   
105.
This paper reports the immunostimulatory and protective effects of Aloe vera extracts (aqueous and ethanolic) against coccidiosis in industrial broiler chickens. The study was divided into two experiments. Experiment-I was conducted for the evaluation of immunostimulatory activity of A. vera and experiment-II demonstrated the protective efficacy of A. vera extracts against coccidiosis in chickens. Results of the experiment-I revealed significantly higher (p<0.05) lymphoproliferative responses in chickens administered with ethanolic extract of A. vera as compared to those administered with aqueous extract and control group. Microplate haemagglutination assay for humoral response on day 7th and 14th post primary and secondary injections of sheep red blood cells (SRBCs) revealed significantly higher (p<0.05) anti SRBC antibody (total Igs, IgG and IgM) titers in chickens of experimental groups as compared to the control group. None of the extracts, however, demonstrated significant effects on the development of lymphoid organs. Results of experiment-II revealed maximum protection (60%) in chickens administered with aqueous Aloe extract as compared to the ethanolic extract administered chickens (45%). Mean oocysts per gram of droppings in the control group was significantly higher (p<0.05) as compared to the chickens in both the experimental groups. Chickens administered with aqueous Aloe extract showed a minimal mean lesion score (2.3) followed by those administered with ethanolic Aloe extract (2.6) and control chickens (3.05) for caeca, and a similar pattern was observed for intestinal lesion scoring. Further, significantly higher weight gains and antibody titers (p<0.05) were observed in chickens administered with A. vera extracts as compared to those in the control group. It was concluded that A. vera may be a potential and valuable candidate to stimulate the immune responses and can be used successfully as an immunotherapeutic agent against coccidiosis in industrial broiler chickens.  相似文献   
106.
A new steroidal derivative, urs Stigmast-4, 20 (21), 23-trien-3-one and other four compounds were isolated from the leaves of Bryophyllum pinnatum. The structure of this new steroid was elucidated and established by standard spectroscopic methods. Carrageenan induced paw edema model was used for anti-inflammatory and acetic acid induced model used for analgesic activity. This new steroidal compound was found to be active in reducing inflammation (% inhibition 87.29 and 84.45 respectively) when compared with diclofenac. Further, it showed 75.72% protection in analgesic activity in acetic acid induced writhing test in mice. In conclusion the % inhibition against carrageenan induced rat paw edema and % protection against acetic acid induced writhings showed by new compound revealed that the anti-inflammatory and analgesic activity of aqueous extract B. pinnatum are mainly due to the presence of this steroidal compound.  相似文献   
107.
108.
109.
Diazinon is one of the most widely used organophosphates in agriculture. Toxic effects of diazinon are due to the inhibition of acetylcholinesterase, an enzyme needed for proper nervous system function. This study was designed to investigate the effects of diazinon at different doses on pancreas and liver tissues and in which dose level diazinon shows its effects. Sixty male Wistar albino rats were included in this study. Animals were initially divided into control and diazinon given groups. There were 10 animals in the control group and 50 animals in diazinon administered group. The latter was divided into five equal subgroups: 25, 50, 100, 200 and 300 mg/kg of diazinon administered groups. Control group was given only saline. All animals in 300 mg/kg diazinon group died. After 24 h, rats were sacrificed under ether anesthesia. Tissue and blood samples were taken for biochemical and histopathological analysis. Sample tissues were examined under light microscope. In biochemical analysis, AST, ALT, LDH, amylase and lipase enzyme activities were measured. One-way ANOVA test was used to compare the groups. In 200 mg/kg diazinon given group, it has been observed some histopathological changes in pancreas and liver tissues. Cholinesterase activities were significantly decreased and alkaline phosphatase levels were increased in all diazinon given groups, when compared with the controls. There was statistically significant difference between the control and diazinon given groups by means of serum amylase, lipase, ALT and AST activities (p < 0.05). LDH activities were significantly increased in 100 and 200 mg diazinon given groups, when compared with the controls (p < 0.05). Histopathological changes were observed only in 200 mg diazinon given group. This evidence suggest that diazinon effect is dose dependent and this is possibly 10-15% of the LD50 dose (200 mg/kg), which cause acute pancreatitis and histopathological changes in liver.  相似文献   
110.
The pod borer Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is an important insect pest of chickpea and several other crops in Asia, Africa and Australia. The present studies were carried out on integration of various practices for the management of H. armigera in Punjab, Pakistan, during 2004-05. Chickpea variety ‘CM-2000’ was selected for evaluating various strategies such as cultural, mechanical, biological, microbial, and chemical control, individually and in various possible combinations, for the management of H. armigera at three different locations. Integration of weeding, hand picking and indoxacarb (an oxadiazine insecticide) proved to be the most effective in reducing the larval population and pod infestation and resulted in the maximum grain yield. The larval population of the combined effect of these practices was not significantly different from hand picking + indoxacarb, weeding + indoxacarb, and indoxacarb alone. Hand picking in combination with Bacillus thuringiensis, and weeding + hand picking, also controlled the larval population significantly, but was inferior to the above treatments. The release of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) did not control H. armigera. It was concluded on the basis of the cost — benefit ratio that hand picking was the most cost-effective method for the control of H. armigera, while the maximum increase in grain yield was obtained in plots with weeding, hand picking, and indoxacarb.  相似文献   
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