共查询到20条相似文献，搜索用时 78 毫秒
1.
一组混合菌群还原硫酸盐的特性 总被引：1，自引：1，他引：0
为了利用硫酸盐还原法消除硫酸盐和重金属离子对环境的污染,从凤阳城区排水沟中富集和驯化获得硫酸盐还原菌菌群,研究了硫酸盐还原菌群对含硫氧酸盐的还原,以及温度、pH、盐度、氧气和Fe2+等因素对菌群还原硫酸盐能力的影响。结果表明,该菌群可以利用乳酸钠还原硫代硫酸盐、硫酸盐,不能还原亚硫酸盐;最适合的生长温度为36℃,pH 7.5,可在3%的氯化钠浓度下生长;在兼性厌氧条件下对硫酸盐还原能力最强;硫酸盐还原率随着Fe2+浓度的增加而增大。菌群接种量为10%,FeSO4初始浓度为2000 mg/L,培养30 h后硫酸盐还原率达到95%以上。 相似文献
2.
油页岩开采利用地下水有机污染物生物降解的研究 总被引：1，自引：1，他引：0
为解决油页岩在开采利用中有机物对地下水的污染问题,试验采用驯化培养的石油降解菌,对地下水中的有机污染物进行生物降解。在低温(10℃)、120 r/min条件下,通过室内试验,确定菌群降解地下水中有机污染物的最佳pH为7,接种量为5 mL（8×106个/mL）,初始浓度为200 mg/L,辅助氮源为氯化铵(0.05%),辅助磷源为磷酸二氢铵(0.05%)。在此最佳条件下,反应6天后总石油烃质量浓度为33.94 mg/L,菌群对总石油烃及COD的降解率分别为83.03%及67.58%。通过对降解过程的动力学研究分析可知,总石油烃初始浓度为20 mg/L时的降解符合一级动力学方程,50~300 mg/L时的降解符合零级动力学方程。 相似文献
3.
探究毛栓菌27-1漆酶对酚酸类化合物的降解效能,为竹林地酚酸类自毒物质降解提供依据。采用超高效液相色谱检测法,通过测定菌液处理后酚酸含量变化,研究毛栓菌27-1漆酶对10种酚酸类化合物的降解特性。结果表明,毛栓菌27-1漆酶能完全降解酚酸类化合物中的香草酸、咖啡酸和芥子酸;丁香酸、阿魏酸和龙胆酸的降解效果一般,降解率50%左右;原儿茶酸的降解效果较差,降解率达35%;不能降解香豆酸、对羟基苯甲酸和绿原酸。研究不同条件下毛栓菌27-1漆酶降解酚酸类化合物丁香酸的效能,发现在pH 5、温度30℃、丁香酸初始浓度小于100 mg/L时,菌株对丁香酸具有高效降解能力,ABTS溶液作为介体物质加入降解体系后降解效果更好,在浓度为0.5 mmol/L时,降解率可达到100%。毛栓菌27-1产生的漆酶对酚酸类化合物具有良好降解效能。 相似文献
4.
高效降解有机磷农药真菌的分离鉴定及其特性研究 总被引：2，自引：1，他引：1
从有机磷农药严重污染的土壤中分离筛选出有机磷农药高效广谱降解真菌,并对其进行鉴定及降解特性研究。通过有机磷农药驯化培养、形态学和生理生化特性及其18S rDNA序列分析等试验对其进行初步鉴定,研究外界因素初始pH、培养温度、氧化乐果初始浓度等对降解菌的生长量和降解能力的影响。通过驯化分离筛选等过程从污染土壤中筛选到2株可以在高浓度氧化乐果环境下生长的真菌J4和J6,它们经生理生化和18 S rDNA序列测定初步鉴定均为黑曲霉（Aspergillus niger）。研究发现,J4和J6菌株在氧化乐果初始浓度1000 mg/L,pH值分别为6.5和6.0,温度分别为30℃和28℃,摇床转速160 r/min条件下,培养5天后降解菌可达到最佳生长量和降解能力,降解率可分别达77.83%和70.81%,耐受氧化乐果的最大浓度均为5000 mg/L,其生长量和降解能力具有正比例相关性变化趋势;并进一步研究发现,曲霉J4和J6还具有广谱降解有机磷农药的特性。 相似文献
5.
臭氧溶解特性及对哈密瓜中农药残留降解的研究 总被引：1，自引：0，他引：1
为探讨臭氧水处理对农残降解的影响,研究了臭氧水的溶解特性以及臭氧水在不同浓度、不同处理时间、不同pH和不同处理方式对哈密瓜中4种农残（马拉硫磷、毒死蜱、高效氯氰菊酯和百菌清）降解的效果。结果表明：臭氧的溶解度随吸收液体积增大、pH的升高而下降,pH 4时的溶解度最高为10.15 mg/L;哈密瓜中4种农残的降解率随着臭氧浓度的增加、浸泡时间的延长均有不同程度的提高;动态臭氧水处理的降解率显著高于静态处理(P＜0.05);pH 10的臭氧水动态处理30 min效果最佳,马拉硫磷、毒死蜱、高效氯氰菊酯、百菌清4种农药的降解率分别是90.87%、85.62%、78.31%和85.26%。 相似文献
6.
为了解决阿特拉津给土壤带来的污染问题以及寻找吸附效果较好的活性炭基质,本研究利用高效液相色谱(HPLC)技术检测了阿特拉津溶液和悬浮液经煤、木、果和竹质4种生物炭处理后的残留量,并对其在阿特拉津溶液和土壤中的吸附动态进行检测。结果表明,煤质活性炭对初始浓度为100 mg/L和10 mg/L的阿特拉津溶液和悬浮液的吸附效果较好,其吸附率为5.651%~68.42%;当阿特拉津初始浓度为100 mg/L时,煤质活性炭在40 min时对阿特拉津溶液的吸附率高达23.49%;与对照组相比,当阿特拉津的初始浓度为100 mg/L时,土壤中阿特拉津经煤质活性炭处理42天后的残留浓度最低,活性炭吸附率达到91.39%。综上,煤质活性炭能有效降解溶液及土壤中阿特拉津含量,这将为阿特拉津污染土壤的改良研究奠定基础。 相似文献
7.
笔者以太阳光为光源,研究了纳米TiO2降解毒死蜱的反应动力学,考察了纳米TiO2用量、毒死蜱起始浓度及溶液pH值对毒死蜱光催化降解速率的影响,旨在为将来实际生产中降解蔬菜、粮食、水果及农药废水中毒死蜱残留的污染提供依据。结果表明,TiO2最佳用量为50 mg/L;毒死蜱初始浓度越大,降解速率常数越小;在碱性条件下,有利于降解反应的进行。试验条件下毒死蜱的光催化降解符合一级反应动力学规律。 相似文献
8.
石油降解混合菌剂的筛选及降解条件研究 总被引：2，自引：1，他引：1
为了获得石油高效降解混合菌剂及优化的降解条件,从油污土壤、含油废水及原油中经富集驯化分离得到细菌68株、真菌15株,放线菌6株;将所分离的菌株通过初筛、复筛及两两混合拮抗实验,筛选得到Y-4与Y-12及Y-4与Y-37两组石油高效降解混合菌剂,其对石油的降解率均超过60%。同时研究了不同的初始条件对各混合菌剂降解率的影响。结果表明,Y-4与Y-12组合在初始pH 8.0、转速160 r/min、种子液以1:1接种0.5 mL、30~35℃培养7天,Y-4与Y-37组合在初始pH 7.5、转速130~160 r/min、种子液以1:1接种0.5 mL、35℃培养7天,加入的初始原油量越少,基质营养越丰富,其降解率越高。通过实验可知,在适宜的条件下2种混合菌剂的降解率均较高,并且混合菌剂对石油的降解率要高于单菌剂。 相似文献
9.
白腐菌对有机氯农药氯丹的酶促降解特性研究 总被引：1，自引：1，他引：0
为了阐明对有机氯农药氯丹具有高效降解能力的白腐菌Phlebia brevispora的酶促降解特性及规律,在实验室条件下,菌株经过纯培养、超声波破碎和高速离心等过程,提取到胞内粗酶液和胞外粗酶液,研究了降解酶对氯丹的降解及其转化特性。结果显示,处理20 min后,胞内酶及胞外酶对10μmol/L氯丹的降解率分别达到33.2%和10.4%。氯丹胞内酶降解的酶促反应最适温度是32℃,最适pH 5.0,最适条件下反应1 h后的氯丹降解率为49.9%。胞内酶在25~40℃,pH 4.5~6.0范围内均具有较高的降解活性;胞内粗酶液的米氏常数Km为3.49μmol/L,最大反应速率Vmax为8.38μmol/min。在胞内酶及胞外酶培养体系分别检测到完全不同的代谢产物。结果表明,氯丹降解酶系包括胞外酶和胞内酶,其中胞内酶是主要降解酶。胞外酶主要催化氯丹的脱氢和脱氯化氢反应,而胞内酶则主要通过羟基化和置换反应将氯丹转化为一些羟基化产物。 相似文献
10.
为了缓解环境中邻苯二酚的污染,筛选并研究邻苯二酚降解菌,以期为邻苯二酚污染的微生物修复提供备选菌株。从西安污水处理厂水样及陕西苹果园土壤中分离以邻苯二酚为唯一碳源的降解细菌。采用以邻苯二酚为唯一碳源的无机盐培养液,在28℃及150 r/min的恒温摇床中对菌株进行培养,通过测定培养液中剩余的邻苯二酚浓度,计算菌株对邻苯二酚的表观降解率,并通过pH、装样量和浓度3方面对菌株降解特性进行研究。结果表明,在pH 6,装样量50 mL,浓度100 mg/L时,菌体的生长量以及邻苯二酚的降解率达到最大,该菌株显示出良好的应用前景。 相似文献
11.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans. 相似文献
12.
G. H. Kroon 《Euphytica》1994,76(1-2):125-125
Summary
K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes. 相似文献
13.
Hongyan WEI Jian ZHOU Jinguang LU Jingzheng SONG Qiongxi YU Zhihong JIANG 《Medicinal Plant》2019,(6):27-29
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol... 相似文献
14.
Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed. 相似文献
15.
Mohammed Riyazaddin Polavarapu B. Kavi Kishor Are Ashok Kumar Belum V. S. Reddy Rajendra S. Munghate Hari C. Sharma 《Plant Breeding》2015,134(4):423-436
Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums. 相似文献
16.
Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
17.
Summary
Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases. 相似文献
18.
J. T. Fletcher 《Euphytica》1992,63(1-2):33-49
Summary Cultivars of tomatoes, cucumbers, lettuce and peppers have been bred for resistance to one or more pathogens. Some tomato and cucumber cultivars have resistance to a wide range of diseases. Resistance has been transient in many cases and a succession of cultivars with new genes or new combinations of resistance genes has been necessary to maintain control. There has been a number of notable exceptions and these have included durable resistance to such pathogens asFulvia fulva and tomato mosaic virus. With lettuce the resistance situation is complicated by the occurrence of fungicide resistant pathotypes. There are no strains ofAgaricus bisporus purposely bred for disease resistance.In protected flower crops only resistance to Fusarium wilt in carnations has been purposely bred but differences in disease resistance are apparent in cultivars of many ornamental crops. This is particularly so in chrysanthemums where there are cultivars with resistance to many of the major pathogens. Similar situations occur with other flower crops and pot plants. Cultivars of some species have not been systematically investigated for resistance.The need for genetic resistance will increase with the further reduction, in the limits on pesticide use and an increasing public awareness and importance of pesticide pollution.ADAS is an executive agency of the Ministry of Agiculture, Fisheries and Food and the Welsh Office. 相似文献
19.
M. Raj Ahuja 《Euphytica》2009,165(1):5-19
The genetic constitution and diversity of four relictual redwoods are discussed in this review. These include monotypic genera
of the family Cupressaceae: coast redwood (Sequoia sempervirens), giant sequoia (Sequoiadendron giganteum), dawn redwood (Metasequoia glyptostroboides), and alerce (Fitzroya cupressoides). All four species are narrow endemics, share a number of common phenotypic traits, including red wood, and are threatened
species. Fossil history suggests that the ancestors of redwoods probably originated during the Cretaceous and Tertiary periods
and flourished thereafter for millions of years. Towards the end of the Tertiary period began their decline and struggle for
existence that continued during the subsequent geologic upheavals and climate changes, until the survival of the present-day
redwoods in the current restricted locations in the world (USA, China, and South America). Although two species, Sequoiadendron and Metasequoia, are diploids (2n = 22), and the other two are polyploids: Fitzroya a tetraploid (2n = 4x = 44), and Sequoia a hexaploid (2n = 6x = 66); they all share the same basic chromosome number x = 11. The genome size in the hexaploid Sequoia is one of the largest (31,500 MB) in the conifers, while the genome sizes of diploid Metasequoia and Sequoiadendron are about one-third (~10,000 MB) of Sequoia. Genetic diversity in the redwoods is lower than most other gymnosperms, except in Sequoia, which seems to rank near the upper quarter of the coniferous forest trees. Genomic research is sparse in the redwoods, and
should be pursued for a better understanding of their genome structure, function, and adaptive genetic diversity. 相似文献
20.
The induction in vitro of adventitious shoots in Rosa 总被引：8，自引：0，他引：8
Summary Adventitious shoots were formed on excised leaves, roots and callus of Rosa persica x xanthina and on excised leaves of R. laevigata and R. wichuraiana on culture media that included BAP and NAA as growth regulators. Shoots formed freely on freshly cultured callus of R. persica x xanthina but their production declined in successive cultures and ceased after twelve weeks. Transplantation to soil was improved by rooting plantlets in cellulose plugs in vitro and transferring plantlets to soil while still in the plugs. 相似文献