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排序方式: 共有182条查询结果,搜索用时 15 毫秒
1.
《Communications in Soil Science and Plant Analysis》2012,43(5):952-961
A greenhouse assay using an arugula (Eruca sativa L.) hydroponics system was carried out to evaluate the following effects of increasing amounts of cadmium and lead in nutritive solution: (a) production; (b) translocation of cadmium (Cd) and lead (Pb) throughout the plants; (c) possible interactions of Cd and Pb with other mineral elements, transition metals, essential to plants; (d) tolerance limits to Cd and Pb with regard to production; and (e) chelating interaction of Cd and Pb with root substances. The absorption of Cd and Pb increased with increasing dosages in solution. Roots accumulated larger amounts of metals than shoots. Plants develop better with less than 0.025 mg L?1 of Cd, with a damaging Cd concentration of 1 mg L?1. The tolerable Pb concentration was up to 10 mg L?1. Cadmium and Pb translocate poorly in plants and their deleterious effect is due to the deposit of very stable chelates in roots. 相似文献
2.
Rumesh Ranjan Ashish Kumar Swarupa Nanda Mandal 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):588-595
ABSTRACT Nitrogen uptake being part of nitrogen use efficiency (NUE) is largely decided by root traits. Root traits variability has hardly been explored by breeders mainly because of difficulties in scoring. The hydroponic system requiring lesser space for precise phenotyping of large numbers of genotypes independently of the growing season can be a suitable alternative. However, the effectiveness of hydroponic screening methods needs to be verified under the soil condition of the field or pot. In the present study, root traits and NUE were investigated in 19 genotypes under two conditions (hydroponic and pipe filled with soil). Both environments revealed large variability for root traits and NUE under high and low N conditions establishing the absence of any direct selection for these traits in the past. Under both sets of experimentation, NUpE was largely responsible for improved nitrogen efficiency mainly because of higher root biomass. The significant association between the two screening methods i.e. hydroponic and pot filled with soil under both low and high N condition support large scale screening for root traits under hydroponic condition. 相似文献
3.
Teruo NONOMURA Yoshinori MATSUDA Motoaki TSUDA Kazuto URANAKA Hideyoshi TOYODA 《Journal of General Plant Pathology》2001,67(3):224-227
Commercially available tomato cultivars were hydroponically cultured for inoculation, with Ralstonia solanacearum (K-101), which causes bacterial wilt, by pouring an inoculum suspension into the nutrient solution. Cultivar susceptibility
to the bacteria was evaluated, based on the highest percentage of wilting. Because the length of time for wilt appearance
varied among cultivars, some cultivars appeared to be suppressive to the translocation and/or multiplication of the invading
pathogen. Thus, this hydroponic inoculation system is effective for examining levels of susceptibility in tomato cultivars
to bacterial wilt.
Received 13 December 2000/ Accepted in revised form 27 March 2001 相似文献
4.
E.G. Wulff A.T.H. Pham M. Chérif P. Rey Y. Tirilly J. Hockenhull 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(1):69-76
Hydroponically grown cucumber (Cucumis sativus) seedlings were inoculated with zoospores of 1 mycoparasitic (Pythium oligandrum) and 2 pathogenic (Pythium aphanidermatum and Pythium group F) Pythium spp. During the first 2 days after inoculation, all the Pythium spp. caused reduction in the root length. However, roots treated with Pythium oligandrum quickly reached the length of the control and on the 8th day, and for the rest of the experimental period, stimulation of root elongation was noted. Pythium oligandrum was not pathogenic on cucumber and no differences in the fresh weights of control and Pythium oligandrum inoculated plants were observed in the course of the experiment. Pythium group F and Pythium aphanidermatum were pathogenic on cucumber seedlings, but their pathogenicities differed. Thus, while Pythium group F had a constant, negative influence on root length and plant growth, measured as fresh weight, Pythium aphanidermatum caused generalized necroses of the root system, inhibiting consistently root elongation and plant growth and finally causing plant death. Moreover, the zoospores of 2 mycoparasitic species, Pythium oligandrum and Pythium periplocum, were not attracted to roots of cucumber and accumulated on the roots in very low numbers compared to those of the pathogenic species, Pythium aphanidermatum, which were strongly attracted and accumulated in large numbers. Finally, it was also found that Pythium oligandrum colonized the roots very poorly, while Pythium group F and Pythium aphanidermatum were significantly better root colonizers. The significance of these findings is discussed in relation to the ecology of Pythium species and biocontrol. 相似文献
5.
为探究番茄茎秆资源化应用技术及效果,本研究利用番茄茎杆有氧发酵浸提液(EX1)和番茄茎杆厌氧发酵浸提液(EX2)水培番茄,以山崎营养液处理为对照(CK),对番茄植株的生长形态、果实营养品质和挥发性物质等相关指标进行分析。结果表明:1)EX1和EX2处理的株高、茎粗、叶面积和生物量等指标低于CK处理,但番茄果实可溶性固形物、糖酸比、可溶性蛋白和维生素C等指标均优于CK处理,并以EX2处理表现最佳;2)EX1、EX2和CK处理检测到挥发性物质数量依次是39、34和27种;3)EX1、EX2和CK处理的挥发性物质总含量依次是1 403.35、1 931.10和1 368.40μg/kg;4)EX1、EX2和CK处理的番茄特征挥发性物质总量依次是953.82、1 256.60和1 055.06μg/kg。说明单纯使用番茄茎杆浸提液水培番茄,虽然在生长上稍显弱势,但可显著改善果实营养和风味品质。本研究一定程度上使番茄茎秆得到了有效利用,也为其他蔬菜茎秆资源化技术提供理论参考,具有较为广阔的前景。 相似文献
6.
闭合循环水产养殖-植物水栽培综合生产系统的工艺设计及运行效果 总被引:13,自引:0,他引:13
闭合循环水产养殖-植物水栽培综合生产系统主要由鱼类养殖池、蔬菜和花卉水培渠、循环水处理系统构成,是一种新型"养殖-种植-水质净化"生产模式。在上海市青浦区的实践表明:①单位水体红罗非鱼(Tilapiamossambica(♀)×Tilapianilotica(♂))和暗纹东方(Fuguobscurus)的产量分别达到58kg·m-3和12.28kg·m-3,养殖期间,氨氮浓度<1.5mg·L-1,亚硝氮浓度<0.8mg·L-1,DO>5.0mg·L-1;②水栽培蔬菜生长良好,对氨氮、亚硝氮、硝氮、总氮、磷酸盐和COD的最大去除率分别为57.46%、51.72%、3.7%、10.67%、9.72%和21.78%,水培蔬菜渠进水和出水的平均N/P分别为6.60∶1和6.53∶1;③生物过滤器对流经水体的NH 4 N、NO-2 N、COD一次性去除率分别为44.79%、20.31%、20.10%;④泡沫分离—臭氧消毒装置对养殖水体中异养细菌的去除率为93.58%,NH 4 N、NO-2 N的去除率为39.00%、38.10%,能明显提高水体中的pH和DO。 相似文献
7.
Production of haploids, followed by chromosome doubling to produce doubled haploids (DH) represents the most rapid means of
achieving complete inbreeding. In order to improve the androgenetic responses and maximize the production of green regenerants
from selected plants of twenty-five triticale (× Triticosecale, Wittmack) populations (BC1F1, TC1F1, and F2) we used a uniform and optimal growth environment for anther donor plants within a greenhouse hydroponic system. Non-orthogonal
analysis of deviance showed highly significant differences (p < 0.001) among populations for both induction and regeneration. The overall induction response of the populations was very
high with a mean of 50.4 embryoids per 100 anthers plated. Among all tested-populations, M86-6068/TW179//EP80 (TC1F1) was the most responsive for both induction and regeneration which could be associated to its Triticum timopheevii cytoplasm. On the other hand, although populations 80465/II83-194 both as BC1F1 and F2 had a high level of induction response, only a few green plants were regenerated. These populations probably possess a partial
Secale montanum genome, which could be contributing to the low regeneration ability. In conclusion, the need for optimization of donor plant
growth conditions to effectively assess the androgenetic ability of individual populations/lines would be emphasized.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
The objective of this study was to correlate root length of wheat (Triticum aestivum L.) genotypes grown in Al-containing, acidic hydroponic solutions, with root weights from acid-soil experiments and field scores from Brazilian acid-field trials. A total of 43 wheat genotypes, primarily from Brazil, were evaluated by growing seedlings for 4 days in hydroponic solutions containing 0.0–4.0 mg/l Al. The root growth rate of all the genotypes was reduced with the addition of Al to the solution and the Al-sensitive and Al-tolerant wheat genotypes were clearly identified. Genotypes with intermediate Al-tolerance levels showed variable root lengths in response to Al stress. Correlations between root length or a root tolerance index (RTI) in the Al solutions versus acid-soil experiments and acid-field trials were highly significant (r = 0.71–0.85, P < 0.01). The most significant correlation was observed among seedlings grown in 1 mg/1 Al. This study presents evidence that this short duration and simple screening technique provides a highly significant correlation with previous acid-soil Al-tolerance evaluations. Furthermore, the data obtained suggest that hydroponic screening of wheat seedlings for Al tolerance may be used in breeding programmes or in screening germplasm collections. 相似文献
9.
水培过程中营养液中的NH_4-N浓度下降伴随NO_3-N浓度提高,培养过程中溶液活性Al含量下降,pH值降低并非活性Al浓度提高所致,培养液加Al对pH下降有缓冲作用。茶树根系分泌物中有咖啡因和儿茶素类物质,利用培养过茶树的营养液再次培养茶苗,即使通过添加速效N、P、K保持其营养水平,茶树生长仍然受到抑制。据此推断,茶树根系分泌物中的咖啡因和儿茶素类物质具有异株克生作用。 相似文献
10.
Using hydroponics and novel non‐destructive pot culture systems which enable inoculation at specific tuber development stages, the dynamics of common scab infection patterns in potato were studied in order to provide more precise identification of tuber physiological factors associated with susceptibility. At the whole‐tuber level, infection percentages were greatest when Streptomyces scabiei inoculation occurred early; at 2 weeks after tuberization (WAT) 68% of tubers became infected, contrasting with late inoculation (8 WAT), when only 4% infection occurred. The first‐formed internodes were most susceptible to infection, whilst later‐forming and slower‐expanding internodes were less susceptible. Detailed tuber physiological examination of internode 2 showed that pathogen‐induced changes, including increased phellem (periderm) thickness, cell layers and phellem suberization (key physiological features believed critical to S. scabiei infection) were promoted through S. scabiei inoculation. Sequential harvesting showed enhanced phellem suberization (28% greater than the control) within 7 days of pathogen exposure, while phellem thickness and layer responses were also initiated early in the infection process (10–14 days after pathogen exposure) and these responses were independent of symptom expression. Differences in cultivar response were observed, with greater phellem suberization observed 10 days after tuberization (DAT) in the common‐scab‐tolerant cv. Russet Burbank than in the susceptible cv. Desiree. Likewise, Russet Burbank had thicker and more numerous cell layers in the phellem (up to eight cell layers) during early tuber growth (20–30 DAT) than Desiree (up to six cell layers). 相似文献