首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
In Los Tuxtlas, Mexico, the local Popoluca people maintain the traditional management of their maize agroecosystems. However, it is not known whether the loss of agrodiversity over recent decades has affected mycorrhizal populations, nutrient availability, and crop productivity. This study utilized linear mixed effect models to analyze the relationship between agrodiversity (three, six, and greater than or equal to eight cultivated species) and (a) arbuscular mycorrhizal fungi (AMF) inoculum potential, measured as the most probable number (MPN) of propagules and colonization level, (b) nutrient availability, and (c) aboveground maize productivity. We also investigated the relationship between soil nutrient content and inoculum potential. Soil samples were taken before planting, and during flowering, in the 2009 maize cycle. We found that AMF colonization level of maize roots and P availability increased with planted species richness, but that this effect only occurred at the flowering sampling date. Plots with a higher MPN of propagules presented increased C and NO 3 ? contents and lower C/N ratio than those with lower MPN of propagules, regardless of agrodiversity. Soils that produced the highest maize root colonization level also featured high P availability and N content. We conclude that decreased agrodiversity in these traditional systems does not significantly affect the soil MPN of propagules, but may have a negative impact on the ability of the mycorrhizal community to colonize maize roots, as well as reducing the availability of P, which is often the most limiting nutrient in tropical soils.  相似文献   

2.
Leguminous plants can be dual colonized by rhizobia (Rh) and arbuscular mycorrhizal fungi (AMF). To test the affections of nodulation, colonization of AMF (AMF%) and the growth responses of white clover under crossed low nitrogen (N) and phosphorus (P) fertilization levels. The results showed that the nodule numbers were much more dense, significantly increased by AMF symbiosis, negatively controlled by the N levels but had no effect due to P levels. The influence of nodule numbers via AMF % was beyond P availability. The AMF% was related and favored with the better N and P nutrition, which may have better photosynthetic carbon (C) availability. The plant growth and C accumulation were significantly increased via rhizobium inoculation but were negatively affected by the AMF. The AMF colonization beyond P fertilization had strong effects on nodulation. Compared with rhizobium symbiosis, the AMF colonization requires a more C-composition between these two tertiary symbioses.  相似文献   

3.
Previous research, mostly in temperate agricultural systems, has shown that management practices such as fallow period, tillage, crop rotation, and phosphorus (P) fertilizer applications can influence the abundance of arbuscular mycorrhizal fungi (AMF), but relatively little is known about their effect in smallholder farmers’ fields in sub-Saharan Africa. In this study, we evaluated the effect of four subsistence crops that form associations with AMF, moderate P fertilization, tillage, and fallow period on the subsequent AMF abundance on three contrasting low fertility soils in south-western Zimbabwe. Arbuscular mycorrhizal fungal abundance was estimated based on early mycorrhizal colonization of maize (Zea mays L.) or lablab (Lablab purpureus L.) following the various treatments. The previously grown crop significantly affected AMF abundance (p < 0.001). It was highest after lablab followed by pigeonpea (Cajanus cajan L.), maize, and groundnut (Arachis hypogaea L.), and there were significant positive correlations between AMF abundance and aboveground biomass of pigeonpea, lablab, and maize. Contrary to much previous research, P fertilization, fallowing, and tillage did not significantly decrease AMF abundance. In smallholder farmers’ fields in the semi-arid tropics of sub-Saharan Africa, therefore, growing vigorous mycorrhizal plants prior to the dry season could be more important than minimizing P fertilizer applications, fallow periods, and tillage to maintain or increase AMF abundance.  相似文献   

4.
We have evaluated the effectiveness of arbuscular mycorrhizal fungi (AMF) inoculation (+M and ?M) at 0, 60, and 120 kg ?ha?1 of P fertilizer on crop growth (IEg), plant P nutrition and yield (IEy), and on mycorrhization occurrence in a processing tomato crop. Two experiments were carried out in calcareous soil under field conditions. Phosphorus fertilization had no effect on crop growth and yield. At harvests, +M plants showed higher aerial dry weight, fruit fresh weight, and P concentration. Inoculated plants produced larger inflorescences, higher flower number, and total and marketable fruit number compared with ?M plants. At P0 and P60, plants associated with exogenous AMF were able to enhance P recovery, nevertheless factors other than the P uptake improvement concurred to make the inoculation effective. In both years, P fertilization enhanced IEg and IEy, and the application of 60 kg ?ha?1 of P in inoculated soil was enough to reach high production level (134 Mg ?ha?1). In the first trial, due to earlier root mycorrhization in inoculated and P fertilized soil, higher IEg and IEy were obtained compared with the second experiment. In the latter, during the initial phase, plant growth was more affected by P fertilization than by soil arbuscular mycorrhizal (AM) inoculation. Root mycorrhization by native AM fungi indicates that the intensive management of the investigated agro-system did not depress fungi infectivity; however, it caused the selection of less effective AMF. The application of selected AMF as a biofertilizer may represent an innovative ecosustainable practice for improving the crop profitability for growers while reducing the need for P fertilization.  相似文献   

5.
ABSTRACT

This work was conducted to study phosphorus (P) efficiency of two maize genotypes (Zea mays, L.) in calcareous soil grown in potted soil with two levels of P in soil by adding 40 and 270 mg P/kg soil. Half of the pots were inoculated with arbuscular mycorrhizal fungi (AMF) (Rhizoglomus irregulare). The maize genotypes were harvested two times at 35 and 50 days after transplanting. The plant dry matter, root length and Plant P uptake of maize genotype Hagen 1 without mycorrhizal fungi (AMF) increased significantly compared with Hagen 9 at a low P level. In contrast, there was no significant difference between two maize genotypes inoculated with AMF under the same P level. The predicted value increased rapidly with increasing P levels from about 70% up to 97% in both maize genotypes with and without mycorrhizal fungi. At a low P level, the mycorrhizae hyphae contributed by about 31.6% and 30.2% of the predicted total P uptake in maize genotype Hagen 1 and Hagen 9, respectively. The results of this study suggested that the P-inefficient genotype Hagen 9 improved with inoculation with mycorrhizal fungi under a low P level at the same conditions of this experiment. Also, root growth system and mycorrhizal hyphae length would be a suitable plant parameter for studying P efficient maize genotypes, especially under limited P supply. The current study clearly pointed out that the mechanistic simulation model (NST 3.0) provides useful tools for studying the role of AMF in P uptake of plant.  相似文献   

6.
In terrestrial ecosystems, plants are frequently in symbiosis with arbuscular mycorrhizal fungi (AMF) with mineral nutrients and photosynthesis carbon exchanges in between. This research sought to identify the effects of phosphorus (P) levels on the nitrogen (N) uptake via extraradical mycelium (ERM) and the mycorrhizal growth response (MGR) of maize plants within the AMF symbiosis. Pots were separated into root compartments and hyphae compartments (HCs) with two layers of a 30‐μm mesh membrane and an air gap in between, where only hyphae could pass through, to avoid both N diffusion and root growth effects. Maize plants were inoculated with Rhizophagus irregularis with different N fertilization in HCs under two different P fertilization levels. Our results indicated that a strong increase in MGR with low‐P fertilization. The same tendency was not observed with high‐P fertilization, although both had a large increase in P concentration as a potential source of growth in shoot tissue of mycorrhizal plants. Substantial effects (10.5% more N) were observed in the case of high‐P availability for the host plants from ERM fed with N, whereas under low‐P conditions ERM may prioritize P uptake rather than N uptake. The AM fungi increase the uptake of N and P, which are most limiting in the soil with fewer forces from soil resources. In addition, there was still more P accumulated than N due to the high N for ERM with high‐P supply. Low N in HCs corresponded with a lower colonization rate in roots but with high hyphae density in HCs; this result suggest that N and P availability might change the ratio of extraradical to intraradical hyphae length.  相似文献   

7.
No-tillage systems contribute to physical, chemical and biological changes in the soil. The effects of different tillage practices and phosphorus (P) fertilization on soil microbial biomass, activity, and community structure were studied during the maize growing season in a maize–soybean rotation established for 18 years in eastern Canada. Soil samples were collected at two depths (0–10 and 10–20 cm) under mouldboard plow (MP) and no-till (NT) management and fertilized with 0, 17.5, and 35 kg P ha?1. Results show that the duration of the growing season had a greater effect on soil microbiota properties than soil tillage or P fertilization at both soil depths. Seasonal fluctuations in soil microbial biomass carbon (SMB-C) and nitrogen (SMB-N), in dehydrogenase and alkaline phosphomonoesterase activities, and in total phospholipids fatty acid (PLFA) level, were greater under NT than MP management. The PLFA biomarkers separated treatments primarily by sampling date and secondly by tillage management, but were not significantly affected by P fertilization. The abundance of arbuscular mycorrhizal fungi (AMF; C16:1ω5) and fungi (C18:2ω6,9) was lower under NT than MP at the 10–20-cm soil depth in July. Phosphorus fertilization increased soil microbial biomass phosphorus (SMB-P) and Mehlich-3 extractable P, but had a limited impact on the other soil properties. In conclusion, soil environmental factors and tillage had a greater effect on microorganisms (biomass and activity) and community structure than P fertilization.  相似文献   

8.
Straw return can be used to reduce fertilizer input and improve agricultural sustainability and soil health. However, how straw return and reduced fertilizer application affect beneficial soil microbes, particularly arbuscular mycorrhizal fungi (AMF), remains poorly understood. Here, we conducted a five-year field experiment in a rainfed maize field on the Loess Plateau of northwestern China. We tested four treatments with straw return combined with four nitrogen (N) application rates, i.e., 100%, 80%, 60%, and 0% of the common N application rate (225 kg N ha-1 year-1) in this region, and two reference treatments (full or no N application), with three replicates for each treatment. Mycorrhizal colonization was quantified and AMF communities colonizing maize roots were characterized using Illumina sequencing. Forty virtual taxa (VTs) of AMF were identified in root samples, among which VT113 (related to Rhizophagus fasciculatus) and VT156 (related to Dominikia gansuensis) were the predominant taxa. Both root length colonization and AMF VT richness were sensitive to N fertilization, but not to straw return; furthermore, both gradually increased with decreasing N application rate. The VT composition of the AMF community was also affected by N fertilization, but not by straw return, and the community variation could be well explained by soil available N and phosphorus concentrations. Additionally, 60%, 80%, and full N fertilization produced similar maize yields. Thus, our study revealed the response patterns of AMF to straw return and N fertilizer reduction and showed that straw return combined with N fertilizer reduction may be a promising practice to maintain mycorrhizal symbiosis concomitantly with crop productivity.  相似文献   

9.
ABSTRACT

The need for salinity resistance in turfgrass is increasing because of the enhanced use of effluent and other low-quality water for turfgrass irrigation. Although most turfgrasses form an arbuscular mycorrhizal fungus (AMF) symbiosis, there is little information on the mycorrhization of turfgrass species. Therefore, the aim of this study was to determine the effects of three AMF species, Glomus intraradices Schenck & Smith, Glomus etunicatum Becker & Gerdemann, and Glomus deserticola Trappe & John, and a mixture thereof on the growth, productivity, and nutrient uptake of two species of cool-season turfgrasses, Challenger Kentucky bluegrass (Poa pratensis L.) and Arid tall fescue (Festuca arundinacea Schreb.), and to relate the effects to colonization of the roots by mycorrhiza to assess the dependency of the plants (mycorrhizal dependency [MD]). Following the experimental period (4 months) and measurements, the mycorrhizal inoculated plants had significantly greater biomass production compared to that of non-inoculated plants. MD and shoot mineral contents (particularly P) differed among turfgrass hosting AMF, and the highest value (13%) occurred for P. pratensis and F. arundinacea seedlings colonized with G. intraradices and G. deserticola, respectively. The P content was highest for the F. arundinacea/mixed AMF combination compared to other treatments. We confirmed that mycorrhizal inoculation (P. pratensis/G. intraradices and F. arundinacea/mixed AMF combinations) enhanced plant productivity and nutrient uptake (especially P) even under non-optimum conditions.  相似文献   

10.
菌根化育苗对玉米生长和养分吸收的影响   总被引：2，自引：2，他引：0  
【目的】丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)侵染作物根系形成菌根共生体系对于作物吸收磷具有重要作用,但该结果大多来源于室内受控试验,有限的田间试验因环境条件、试验材料与接种技术等差异致使AMF菌剂应用效果不一。本研究通过玉米菌根化育苗和田间移栽,分析了接种AMF对玉米生长、养分吸收、籽粒产量及养分含量的影响,以期推进菌根技术的实际生产应用。【方法】以自交品系玉米B73为供试作物,于2018年5月至10月在北京市延庆区进行了田间试验。田间小区设置基施磷(+P)和不施磷(–P)处理。供试AMF为Rhizophagus irregularis Schenck&Smith BGC AH01。玉米种子催芽后,分别播入加入AMF菌剂(+M)和菌剂过滤液(–M)的育苗钵内,培养两周后移栽至田间。玉米在田间条件下生长至拔节期时,使用便携式光合仪测定叶片光合速率与气孔导度,取样测定地上部与根部干重和养分元素含量,同时测定菌根侵染率;在玉米完熟期取样,测定籽粒百粒重、籽粒产量及养分含量。【结果】无论田间施磷与否,接菌植株根系的菌根侵染强度和丛枝丰度均显著高于不接菌植株。不施磷情况下,+M处理显著提高了玉米根系干重,玉米生长的菌根依赖性(163.7%)显著高于施磷情形(124.1%)。–P–M处理玉米叶片的光合速率和气孔导度显著低于其他3个处理。–P+M处理玉米叶片的光合参数、玉米地上部和根部磷含量与+P+M均无显著差异。与–P–M处理相比,–P+M显著提高了玉米籽粒产量和百粒重,同时也提高了籽粒中锌、锰、镁等矿质养分的含量,且与+P+M处理相比均无显著差异。【结论】玉米幼苗接种AMF后再移栽到田间,可以显著提高拔节期玉米根系的菌根侵染率,促进玉米地上部和根部对磷及锌、锰和镁的吸收,进而促进玉米的生长,提高籽粒产量和养分含量。本试验条件下,菌根化育苗可以达到与施磷同样的效果,在保障作物不减产的前提下减少磷肥施用量。  相似文献   

11.
Earthworms and arbuscular mycorrhizal fungi (AMF) are important macrofauna and microorganisms of the rhizosphere. The effect of the inoculation of soil with earthworms (Aporrectodea trapezoides) and mycorrhiza (Rhizophagus intraradices) on the community structure of mycorrhizal fungi and plant nutrient uptake was determined with split plots in a maize field. Maize plants were inoculated or not inoculated with AMF, each treated with or without earthworms. Wheat straw was added as a feed source for earthworms. Inoculating AMF significantly increased maize yield (p?<?0.05), and the yield was further enhanced by the addition of earthworms. Alkaline phosphomonoesterase activities, soil microbial biomass carbon (SMBC) and nitrogen (SMBN) increased with the addition of both earthworms and AMF. Soil inorganic N and available K were positively affected by earthworms, while available P showed a negative relationship with AMF. Treatment with both AMF and earthworms increased shoot and root biomass as well as their N and P uptake by affecting soil phosphomonoesterase and urease activities, SMBC, SMBN, and the content of available nutrients in soil. The applied fungal inoculants were successfully traced by polymerase chain reaction with novel primers (AML1 and AML2) which target the small subunit rRNA gene. The amplicons were classified by restriction fragment length polymorphism and sequencing. Moreover, field inoculation with inocula of non-native isolates of R. intraradices appeared to have stimulated root colonization and yield of maize. Adding earthworms might influence native AMF community, and the corresponding abundance increased after earthworms were inoculated, which has positive effects on maize growth.  相似文献   

12.
A potculture study was conducted in soils collected from long-term fertilizer experiment (LTFE) being kept up as far the past 40 years to determine whether arbuscular mycorrhizal fungus (AMF) Rhizoglomus intraradices colonization changes the active and passive pools of carbon in a maize (Zea mays) – finger millet (Eleusine crocana)- cowpea (Vigna sinensis) cropping sequence in the Experimental Farm of the Tamil Nadu Agricultural University, Coimbatore, India. Soil samples were processed, sterilized and maize plants were grown in various fertility gradients in the absence (M-) or presence (M+) of AMF (Rhizoglomus intraradices) inoculation. The data have clearly shown that M+ soils had consistently higher active pools such as water soluble carbon, hot water soluble carbon and biomass carbon (M- 189; M + 305 mg kg?1), and passive pools such as soil organic carbon (M- 4.17; M + 4.31 mg g?1) and total glomalin. Among the fertility gradients, 100% NPK + Farm Yard Manure (FYM) with or without mycorrhizal fungal inoculation registered higher values for both active and passive pools of C but the response was more pronounced in the presence AMF inoculation. Overall, the data suggest that mycorrhizal fungal inoculation assists in effective carbon sequestration in an intensive cereal-legume cropping system.Abbreviations: AMF: Arbuscular mycorrhizal fungi; DAS: Days After Sowing; LTFE: Long-Term Fertilizer Experiment; WSC: Water soluble organic carbon; HA: Humic acid; FA: Fulvic acid; HWSC: Hot water soluble carbon  相似文献   

13.
More details have yet to be indicated on the interactions between arbuscular mycorrhizal (AM) fungi and phosphorus (P) chemical fertilization under field conditions. Accordingly, the objectives were to: (1) evaluate the combined effects of mycorrhizal fungi and chemical P fertilization on maize yield, yield components, and nutrient uptake and (2) indicate the optimum rate of P chemical fertilization (P1, P2, P3) with the use of mycorrhizal fungi (Glomus intraradices and G. mosseae). A factorial experiment using randomized complete blocks with three replicates, conducted at the Research Station of the Faculty of Agriculture, Islamic Azad University, Tabriz branch, Iran. Results indicated the significant effect of P, AM fungi, and their interaction on most of the measured traits. Grain yield (7909.3 kg/ha), maize nutrient content of P (0.39%), zinc (Zn) (42.1 mg/kg), iron (Fe) (68.3 mg/kg), and the colonization rate (47.5%) were all the highest by the interaction of G intraradices × P2.  相似文献   

14.
The interactive impacts of arbuscular mycorrhizal fungi (AMF, Glomus intraradices) and earthworms (Aporrectodea trapezoides) on maize (Zea mays L.) growth and nutrient uptake were studied under near natural conditions with pots buried in the soil of a maize field. Treatments included maize plants inoculated vs. not inoculated with AMF, treated or not treated with earthworms, at low (25 mg kg−1) or high (175 mg kg−1) P fertilization rate. Wheat straw was added as feed for earthworms. Root colonization, mycorrhiza structure, plant biomass and N and P contents of shoots and roots, soil available P and NO3−–N concentrations, and soil microbial biomass C and N were measured at harvest. Results indicated that mycorrhizal colonization increased markedly in maize inoculated with AMF especially at low P rate, which was further enhanced by the addition of earthworms. AMF and earthworms interactively increased maize shoot and root biomass as well as N and P uptake but decreased soil NO3−–N and available P concentrations at harvest. Earthworm and AMF interaction also increased soil microbial biomass C, which probably improved root N and P contents and indirectly increased the shoot N and P uptake. At low P rate, soil N mobilization by earthworms might have reduced potential N competition by arbuscular mycorrhizal hyphae, resulting in greater plant shoot and root biomass. Earthworms and AMF interactively enhanced soil N and P availability, leading to greater nutrient uptake and plant growth.  相似文献   

15.
The improvement of the nutritional quality of lettuce by its association with arbuscular mycorrhizal fungi (AMF) has been recently reported in a previous study. The aim of this research was to evaluate if the fertilization with three P sources differing in water solubility affects the effectiveness of AMF for improving lettuce growth and nutritional quality. The application of either water-soluble P sources (Hewitt's solution and single superphosphate) or the water-insoluble (WI) fraction of a "rhizosphere-controlled fertilizer" did not exert negative effects on the establishment of the mycorrhizal symbiosis. AMF improved lettuce growth and nutritional quality. Nevertheless, the effect was dependent on the source of P and cultivar. Batavia Rubia Munguía (green cultivar) benefited more than Maravilla de Verano (red cultivar) in terms of mineral nutrients, total soluble sugars, and ascorbate contents. The association of lettuce with AMF resulted in greater quantities of anthocyanins in plants fertilized with WI, carotenoids when plants received either Hewitt's solution or WI, and phenolics regardless of the P fertilizer applied.  相似文献   

16.
Despite a general consent about the beneficial contribution of arbuscular mycorrhizal fungi (AMF) on natural ecosystems, there is an intense debate about their role in agricultural systems. In this work, soybean (Glycine max L.) and sunflower (Helianthus annuus L.) field plots with different P availabilities were sampled across the Pampean Region of Argentina (> 150 samples from Mollisols) to characterize the relationship between available soil P and indigenous mycorrhizal colonization. A subsequent pot experiment with soybean and sunflower was carried out to evaluate the effect of P supply (0, 12, and 52 mg P kg–1) and AMF inoculation on AMF colonization and crop responsiveness to P in a Mollisol. Both crops showed high AMF colonization in the field (average: 55% for soybean and 44% for sunflower). While mycorrhizal colonization in soybean was significantly and negatively related to available soil P, no such trends were apparent in sunflower. Also, total biomass was 3.5 and 2.0 times higher in mycorrhizal than in nonmycorrhizal pot‐grown soybean under low‐ and medium‐P conditions, respectively. Sunflower, on the other hand, did not benefit from AMF symbiosis under medium and high P supply. While mycorrhization stimulated P‐uptake efficiency in soybean, the generally high P efficiency in sunflower was not associated with AMF symbiosis.  相似文献   

17.
The population dynamics of naturally-occurring antibiotic producing and nitrogen fixing rhizobacteria, as well as of arbuscular mycorrhizal fungi (AMF) was investigated for a hybrid of maize (Lo964×Lo1016) in comparison to its two parental lines (Lo964 and Lo1016), during four successive 5-week-long growth cycles in the same pot. Beneficial rhizobacteria, such as nitrogen fixers and 2,4-diacetylphloroglucinol (DAPG) and pyrrolnitrin (PRN) producers, as well as AMF were stimulated in the hybrid rhizosphere earlier than in those of the two parental lines. In fact, they were molecularly detected in all rhizospheric samples of the hybrid, independently of the cycle, whereas for the parental lines positive detections occurred only for samples collected after at least two growth cycles. Interestingly, a MPN-PCR approach on rhizospheric DNA samples indicated that, when detected, beneficial rhizobacteria reached similar density in all maize genotypes (2×103 to 2.2×104 target DNA sequences/g?1 of root). Concerning the AMF, even if the three maize genotypes were cultivated in the same soil, it appears that each maize genotype stimulates the AMF population differently. Both the hybrid and the Lo964 line were able to select, in the observed time period, their own adapted phylogenetic AMF subgroups (Glomus A for the hybrid, Archeospora for Lo964), whereas the Lo1016 line was not.  相似文献   

18.
Cowpea is an important crop that serves as a legume and vegetable source to many smallholder farmers in sub-Saharan Africa. Soil fertility is a significant limitation to its production thus; inoculation with beneficial soil biota such as arbuscular mycorrhizal fungi (AMF) could improve its performance. However, plant–AMF interaction could vary based on crop cultivar hence affecting overall crop production. The present study aimed at determining the effect of AMF inoculation and soil sterilization on root colonization and growth of a wild-type and three modern cowpea cultivars grown by smallholder farmers in Kenya. Potted cowpea plants were inoculated with a commercial AMF inoculum comprising of Rhizophagus irregularis, Funneliformis mosseae, Glomus aggregatum and Glomus etunicatum and maintained in a greenhouse for 40 days. After harvesting, mycorrhizal colonization, nodule number and dry weight, root and shoot dry weights, nitrogen (N,) phosphorus (P) and potassium (K) content were determined. Interestingly, the modern cultivars showed significantly (p < 0.001) higher root colonization, nodulation, shoot P and N compared to the wild-type cultivar. Moreover, a strong positive correlation between AMF root colonization and shoot P (r2 = 0.73, 0.90, p < 0.001), AMF root colonization and shoot N (r2 = 0.78; 0.89, p < 0.001) was observed in both sterilized and non-sterilized soil, respectively. Soil sterilization affected root colonization and growth parameters with plants grown in non-sterilized soil performing better than those grown in sterilized soil. This study provides major evidence that modern cowpea cultivars are still responsive to mycorrhizal inoculation suggesting that modern breeding programs are not deleterious AMF symbiosis.  相似文献   

19.
Soil salinity and arbuscular mycorrhizal fungi (AMF) influence the soil hydrophobicity. An experiment was performed to determine the effects of soil salinity and AMF species on soil water repellency (SWR) under wheat (Triticum aestivum L.) crop. Six AMF treatments, including four exotic species (Rhizophagus irregularis, Funneliformis mosseae and Claroideoglomus claroideum, a mix of three species), one mix native AMF species treatment and an AMF-free soil in combination with four salinity levels (1, 5, 10, and 15 dS m?1) were used. The soil repellency index (RI) increased with salinity increment ranging from 2.4 to 10.5. The mix of three exotic and native AMF treatments enhanced the RI significantly compared to AMF-free soil in all salinity levels with one exception for native treatment at 1 dS m?1. Among individual AMF species, the C. claroideum treatment at 10 dS m?1 increased the RI by 67% compared to AMF-free soil. The native AMF treatment was more efficient in root colonization, glomalin production and SWR development at 10 and 15 dS m?1, compared to exotic species. In addition to the net positive effect of salinity on SWR, the AMF influences on the RI were greatly dependent on salinity levels.  相似文献   

20.
Pomegranate (Punica granatum L.) symbiosis with arbuscular mycorrhizae fungi (AMF) is a strategy in saline soils. In this study, two AMF (+AMF and –AMF), two phosphorus (P) fertilizer (+ P and –P), and three irrigation salinity (1, 4, and 8 dS m?1) treatments were studied. The highest salinity level decreased the root colonization by hyphae. Plant growth parameters including shoot dry weight, leaf surface area, and plant height were negatively affected by salinity. However, the growth parameters improved in AMF treatments. Salinity decreased the shoot P concentration and increased the shoot chlorine (Cl). The root and shoot sodium (Na) concentrations were the greatest in unfertilized and P-fertilized treatments, respectively. AMF treatment improved the root and shoot P concentration and reduced the negative effect of salinity on shoot Cl concentrations. In conclusion, the effects of AMF symbiosis on growth and tissue elements concentration depend on irrigation water salinity and P fertilization.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号