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111.
Wild melon diversity in India (Punjab State) 总被引:1,自引:1,他引:0
Anamika Roy S. S. Bal M. Fergany Sukhjeet Kaur Hira Singh Ajaz A. Malik Jugpreet Singh A. J. Monforte N. P. S. Dhillon 《Genetic Resources and Crop Evolution》2012,59(5):755-767
We present here the first comprehensive genetic characterization of wild melon accessions from northern India. The genetic diversity among 43 wild melon accessions collected from the six agro-ecological regions of the Punjab State of India was assessed by measuring variation at 16 Simple Sequence Repeat (SSR) loci, morphological traits of plant habit and fruit morphological traits, two yield-associated traits, root nematode resistance and biochemical composition (ascorbic acid, carotenoids, titrable acidity). Variation among accessions was observed in plant habit and fruit traits and wild melon germplasm with high acidity and elevated carotenoid content and possessing resistance to Meloidogyne incognita was identified in the collection. A high level of genetic variability in wild melon germplasm was suggested by SSR analysis. Comparative analysis using SSRs of the genetic variability between wild melons from the north and other melons from the south and east regions of India and also reference accessions of cultivated melon from Spain, Japan, Korea, Maldives, Iraq and Israel, showed regional differentiation among Indian melon accessions and that Indian germplasm was not closely related to melon accessions from other parts of the world. A highly drought tolerant accession belonging to var. agrestis Naud. was also identified. 相似文献
112.
Oedaleus senegalensis is a serious pest of millet in the Sahel, but the correlation to crop loss remains largely unknown. Therefore, the correlation between densities of O. senegalensis, defoliation level and millet yields was investigated in Niger in 2008, and a simple model to foresee the yield based on these parameters was developed. The yield was significantly correlated to both the density of O. senegalensis and the defoliation level on 17 September. The best model to foresee millet yield involved grasshopper density and cumulated rainfall and may be regarded a tentative method in O. senegalensis control. 相似文献
113.
The effects of salbutamol and norepinephrine on the electrocardiogram (ECG), serum potassium level and enzyme activities were studied in rabbits with hyperkalaemia; norepinephrine and salbutamol may be therapeutically useful. For induction of hyperkalaemia, 300 mM KCl solution was used and then isotonic saline solution containing 6 microg salbutamol and 3.9 microg norepinephrine per ml were administered. Norepinephrine and salbutamol decreased the serum potassium from 7.36 +/- 0.26 and 7.21 +/- 0.31 mmol/L to 5.62 +/- 0.27 and 4.35 +/- 0.33 mmol/L, respectively, and caused the ECG changes (flatness of P wave, widening of QRS complex and bradycardia) to return to the control conditions (time 0). Norepinephrine, but not salbutamol, decreased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) to the control levels. These results suggest that monitoring of the enzyme activities might be useful as it yields indexes suitable for evaluating the therapeutic approach with norepinephrine in hyperkalaemia. 相似文献
114.
Membrane damage caused by the non-specific fungal toxin fusaric acid was less on pretreated than on control leaves when tobacco leaves were pretreated with anti-senescence plant hormones, such as kinetin, benzyladenine or the anti-ozonant N-[2-(2-oxo-1-imidazolidinyl)]ethyl-N'-phenylurea. Similarly, the necrosis caused by mercuric chloride was reduced by the above anti-senescence agents. In addition, in in vitro tests, leaves from selected paraquat-tolerant tobacco plants were less sensitive to Alternaria alternata (Fr) Keissler infection than those of the control paraquat-sensitive tobacco leaves. Paraquat-tolerant Conyza canadensis (L) Cronq weeds naturally selected in vineyards in Hungary showed similar inhibition of senescence to paraquat-tolerant tobacco, expressed as more green leaves and slower development. In accordance with this, the paraquat-tolerant Conyza leaves remained almost symptomless, while paraquat-sensitive plants showed severe symptoms after infection with Botrytis cinerea Pers. Oxidative burst (accumulation of hydrogen peroxide) was attenuated in TMV-infected leaves of Xanthi-nc tobacco as a result of treatment with salicylic acid or in leaves where systemic acquired resistance (SAR) had been induced by a previous TMV infection. Accordingly, superoxide dismutase (SOD) activity was higher in Xanthi tobacco leaves with SAR than without SAR. However, in NahG tobacco, in which SAR cannot develop, there was no augmentation of SOD activity. All the above data support the significance of delayed senescence and antioxidants in the resistance of plants to biotic and abiotic necrosis-inducing agents. 相似文献
115.
Gradually increased radiation doses were applied directly to the ovaries of laparotomized ewes. The effect of these doses was studied as exerted on the qualitative and quantitative changes in the follicular apparatus of the ovaries and adenohypophysis of ewes in anoestrus and upon the recovery processes later on after irradiation. The ovaries irradiated with the dose of 4.79 Gy were found to be heavier when examined after some time from irradiation. The 10th and 30th day from irradiation the number of tertiary follicles decreased, the 100th day from irradiation their number increased to a four-fold level, as compared with the 10th day. Adenohypophysis showed a gradual growth of the number of PAS-positive cells. After the irradiation of ovaries with the dose of 9.57 Gy the ovaries showed the lowest rate of damage on the 10th day from irradiation; the 30th and 100th day from irradiation all the present tertiary follicles were in the state of atresia. In comparison with the control group, the amount of gonadotropic cells of adenohypophysis gradually increased, recovering from a rapid drop after irradiation. When the ovaries were irradiated with the dose of 19.14 Gy, all the tertiary follicles were in the state of atresia and the number of PAS-positive cells of adenohypophysis was lower in comparison with the control group. 相似文献
116.
Marsalková S Cízek M Vasil' M Bomba A Nad' P Datelinka I Jonecová Z Rimková S Kalinácová V Styriak I Bugarský A Gréserová G 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(3-4):145-147
Two strains of lactobacilli (Lactobacillus acidophilus T-135 and Lactobacillus plantarum 4/97) were selected in order to study their inhibitory properties against frequent udder pathogens (Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus uberis, Salmonella enteritidis and Bacillus pumilus), their production of organic acids as well as their ability to survive on the teat skin, the teat duct mucosa and in a lipoid emulsion. Both strains inhibited the tested pathogenic microbes and survived on the investigated surfaces and in an emulsion for more than 6 hours and 11 days, respectively. 相似文献
117.
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119.
食品工业中用迷迭香提取抗氧化物质后的残渣(rosemary processing waste RPW)拌入粉碎的玉米粒可以用作栽培糙皮侧耳的培养料.提取抗氧化剂后的迷迭香残渣RPW-1中所含提取残留的丙酮对栽培有害,RPW-1直接栽培糙皮侧耳所获子实体产量比用RPW-2(废料充分通气,去除残存的丙酮)平均低49%.试验中获得最高生物效率(67%)的培养料配比为RPW-2中加入30%(w/w)粉碎的玉米粒(crushed corn seeds CCS)和2?CO3.增加培养料中的麸皮(wheat bran WB)比例(降低C/N比)可加快菌丝生长速度,但通常导致子实体产量降低.试验中菌丝生长最快(23 d生长9.9 cm)的培养料配比为RPW-2中添加30%(w/w) CCS 和30% (w/w) WB,/N比为24. 相似文献
120.
Lucia Olexikova Marsia Miranda Barbora Kulikova Andrej Bali Peter Chrenek 《Anatomia, histologia, embryologia》2019,48(1):33-39
Sperm plasma membrane is an essential structure of sperm resistance to freezing. Signs of cryodamage can be visible on the sperm plasma membrane. The aim of our study was to evaluate the appearance of plasma membrane and acrosome in fresh and frozen‐thawed chicken sperm using electron and fluorescence microscopy. Semen was collected from 12 sexually mature roosters of Ross PM3 heavy line, diluted with Kobidil+ extender with 16% of ethylene glycol (KEG; control) or with KEG in combination with one of following non‐permeating cryoprotectants: trehalose (KEG‐TRE) or glycine (KEG‐GLY). Fluorescence staining was used for detection of the membrane integrity, apoptotic changes and viability (Annexin V, Yo‐PRO‐1, PI, respectively). Ultrathin sections (70 nm) from samples were prepared to examine sperm head ultrastructure. Freezing process significantly worsened the status of the sperm plasma membranes. In all frozen groups, only about a quarter of the evaluated sperm were graded as class I quality. In the KEG and KEG‐GLY groups, about half of sperm had severe plasma membrane damages (III class). In sperm with extensively damaged membranes (III class), the acrosome–sperm head junction was mostly disturbed. The use of trehalose was more beneficial (p < 0.05) for sperm plasma membrane than the use of glycine. In contrast, a decrease (p < 0.05) in the apoptotic sperm ratio (Yo‐PRO‐1) was noted in the KEG‐GLY group when compared to other treatments. In conclusion, we identified different plasma membrane and acrosome damages in cryopreserved chicken sperm. The loss of acrosomes can contribute to diminishing of fertilization ability of cryopreserved chicken sperm. 相似文献