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991.
Examination of callus micro-grafts in Uapaca kirkiana Müell Arg. was carried out with the objective of determining early signs of graft compatibility. Leaves from U. kirkiana, U. nitida and Jatropha curcas trees were used for callus induction. Two pieces of callus were co-cultured on Murashige and Skoog (MS) medium with different
supplements. Co-cultured calli were embedded in paraffin wax and dissected. The specimens were stained in safranin and fast
green before viewing under a light microscope. Results showed that MS medium with 0.1 mg l−1 thidiazuron (TDZ) and 0.5 mg l−1 naphthaleneacetic acid (NAA) or 1.0 mg l−1 dichlorophenoxyacetic acid (2,4-D) and 0.5 mg l−1 NAA was effective for callus induction. There were no necrotic layers at the unions within U. kirkiana clones and provenances, but a differential growth (irregularity) between U. kirkiana and U. nitida co-cultured calli. Phenol deposits were observed at the union interfaces of U. kirkiana combinations and were high on calli derived from mature trees. Phenol deposits were absent at the union of J. curcas heterografts. Necrotic layers developed at the unions of U. kirkiana and J. curcas micro-grafts and indicating an outright graft incompatibility. Accumulation of phenol deposits at the union interfaces inhibited
graft compatibility in many U. kirkiana combinations. Callus fusion technique can be used to identify partners with an outright graft incompatibility, especially
for distant related plant species. 相似文献
992.
Michaličková Danica Belović Miona Ilić Nebojša Kotur-Stevuljević Jelena Slanař Ondřej Šobajić Sladjana 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(1):122-127
Plant Foods for Human Nutrition - There is a growing body of evidence that tomato consumption reduces the risk of cardiovascular disease, through antioxidative, anti-inflammatory and hypotensive... 相似文献
993.
994.
Neda Tešan Tomić Slavko Smiljanić M. Jović M. Gligorić D. Povrenović A. Došić 《Water, air, and soil pollution》2018,229(9):301
This paper presents the results of determining the pseudo-total concentration of five heavy metals in the soil on which the destruction of ammunition, mines, and explosive devices is carried out by the method of open detonation. In the analyzed area, the concentrations of cadmium, lead, nickel, copper, and zinc were determined, while from the physical properties of the soil were determined the granulometric composition and the pH. The aim of the study is to determine the origin and total load on heavy metals and, based on that, to assess the dangers and impact of the site in terms of the soil pollution by heavy metals. In accordance with the regulations of Bosnia and Herzegovina, the results of the soil testing showed a significant load of copper (up to seven times) and cadmium (up to six times), and exceeding the allowed values for nickel and zinc in some places. Lead was the only metal whose concentration was within the maximum allowed and according to that the soil was classified as unpolluted. A sample of soil from the edge of the pit is the only sample in which all heavy metals, except Ni, were within the maximum allowable concentration. In regard to the concentration of the examined metals, the soil of the pit is classified as medium polluted from the aspect of copper, cadmium, and nickel and highly contaminated with zinc. The concentrations of copper and zinc in the examination area correspond to contaminated soil that represents ecological risk, which requires soil remediation. 相似文献
995.
Fraxinus excelsior seed is not a probable introduction pathway for Hymenoscyphus fraxineus 下载免费PDF全文
We investigated the transmission of Hymenoscyphus fraxineus from infested seed to germinating seedlings of common ash (Fraxinus excelsior) in order to determine the potential risk associated with intra‐ and intercontinental movement of seed. Neither fungal isolations from necrotic or healthy embryos nor PCR testing with H. fraxineus‐specific primers detected the pathogen. Similarly, H. fraxineus was not detected in axenically grown seedlings generated from infested seed lots. The results help clear up prior confusion of the pathogen being seed‐borne. Any remaining surface contamination by pathogen spores could be washed off seeds as a quarantine measure. 相似文献
996.
From the early 2000s there has been a general shift in South Africa in harvesting and extraction systems from the use of semi- to fully-mechanised systems. Any increase in mechanisation, as is occurring in Zululand, will need to take into consideration damage to stumps and the subsequent ability to regenerate by coppice. In 2002, four types of harvesting and extraction systems, arranged in a randomised complete block design, were used to clearfell a stand of E. grandis × E. urophylla. A motor-manual harvesting system was used to carry out the manual harvesting system (Man). The fully mechanised system (Mech) consisted of a single-grip harvesting head used with a tracked excavator to carry out all felling and processing operations. Two additional systems (Man_Mech_3W and Man_Mech_Flexi) had increased levels of mechanisation over that of the Man treatment. Both these harvesting systems made use of a Bell debarker, with loading carried out by a Bell three-wheeled loader in the Man_Mech_3W, and by a Flexiloader in the Man_Mech_Flexi treatments. Data collected from these four treatments were used to determine the effects of mechanised harvesting systems on type and severity of stump damage, coppicing potential and coppice growth over the rotation. Irrespective of harvesting system, more damage occurred to the top than bottom half of the stump, with a significant decrease in coppice regrowth with increasing stump damage. Most damage and least coppice regrowth occurred in the extraction rows where the damage recorded could be attributed to vehicle movement, tear-outs and/or log stripping. There was no significant difference between the harvesting systems in terms of stump mortality, final stem stocking and rotation-end volume. Thus, individual components within each harvesting system can have a larger impact than the overall harvesting system used. Future research should focus on these components, and where associated damage occurs for a specific component, this should be lessened through management intervention, training or technological improvements. 相似文献
997.
998.
G. Gulyas E. Csosz J. Prokisch A. Javor M. Mezes M. Erdelyi K. Balogh T. Janaky Z. Szabo A. Simon L. Czegledi 《Journal of animal physiology and animal nutrition》2017,101(3):502-510
The nano‐sized (100–500 nm) selenium has higher bioavailability and relatively lower toxicity compared to other selenium forms. The objective of the present study was to compare liver proteome profiles of broiler chicken fed with control diet without Se supplementation and diet supplemented with nano‐Se with 4.25 mg/kg DM. Differential proteome analyses were performed by two‐dimensional gel electrophoresis (2D‐PAGE) followed by tryptic digestion and protein identification by liquid chromatography–mass spectrometry (LC‐MS). Seven hundred and eight spots were detected, and 18 protein spots showed significant difference in their intensity (p < 0.05) between the two groups. In response to nano‐Se supplementation, the expression of 8 proteins was higher, and 5 proteins were lower in nano‐Se supplemented group compared to control group. The functions of the differentially expressed proteins indicate that the high dose of selenium supplementation induced a dietary stress. Selenium supplementation may influence the metabolism of fatty acids and carbohydrates and antioxidant system, and increase the quantity of cytoskeletal actin and the expression of actin regulatory protein as well. 相似文献
999.
1000.
不同葡萄品种对霜霉病的抗性 总被引:3,自引:0,他引:3
葡萄霜霉病是葡萄生产上重要的病害之一,通过对辽宁省不同葡萄品种进行室内离体叶片接种和田间自然发病情况调查,以期为葡萄抗性品种的选育和葡萄霜霉病的防治提供科学依据。结果表明,在供试品种中,没有对霜霉病完全免疫的品种,室内离体叶片接种和田间调查结果基本一致,不同品种间霜霉病的抗性存在差异。供试的65个品种中,室内离体叶片接种评价高抗品种3个,抗病品种23个,感病品种24个,高感品种15个;田间自然发病调查评价高抗品种1个,抗病品种19个,感病品种35个,高感品种10个。欧美杂交品种(系)相对欧亚杂交品种(系)较抗病。 相似文献