Inoculation of field-established mulberry and papaya with arbuscular mycorrhizal fungi and a mycorrhiza helper bacterium

The effects of soil inoculation with arbuscular mycorrhizal (AM) fungi and a mycorrhiza helper bacterium (MHB) were investigated on mulberry and papaya plants already established in the field. Ten-year-old mulberry plants (var. M5) were inoculated with Glomus fasciculatum and 1.5-year-old papaya plants (var. Solo) were inoculated with a mixed culture of G. mosseae and G. caledonium with or without Bacillus coagulans at two levels of P fertilizer. Growth, P uptake, yield and AM colonization levels were monitored. Leaf yield in mulberry and fruit yield in papaya were minimal in uninoculated plants given 50% recommended P. However, crop yields of both mulberry and papaya inoculated with AM fungi alone or together with the bacterium and given 50% recommended P were statistically on a par with that of uninoculated plants given 100% recommended P. As inoculation of B. coagulans increased mycorrhiza levels in AM fungal-inoculated plants, this may be included in the class of MHB. Thus, mulberry and papaya already established in the field may respond to AM inoculation and MHB may increase symbiosis development by efficient AM fungi.     

Growth and nutrient status of citrus plants as influenced by mycorrhiza and phosphorus application

To test the hypothesis that high levels of soluble phosphate applied in combination with VAM fungi, to citrus plants, can cause growth depression even in the absence of other limiting factors, and also to test if rock phosphate, under these conditions, may be a satisfactory P source, a greenhouse experiment was conducted using sterilized soil with four levels of phosphate (0, 50, 100 and 200 ppm P) supplied either as soluble P or as rock phosphate. Citrus seedlings were either inoculated with the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus etunicatum or left uninoculated. Six months after the start of the experiment, the plants were harvested and shoot dry weight, P and K uptake, root colonization and the number of spores in 50 cm³ of soil were determined. Significant increases were found in dry matter yields and in P and K contents, due to VAM fungus inoculation, at the zero and 50 ppm soluble P levels and at all rock phosphate levels. At 100 ppm soluble P, the development of VAM plants was equilvalent to that of non-VAM plants, and at 200 ppm, growth was significantly less than that of non-VAM plants. Root colonization and sporulation were reduced at higher P levels. The absolute growth depression of VAM plants at the higher P level was likely due to P toxicity. In addition, high leaf P and K concentrations may have interfered with carbohydrate distribution and utilization in these symbioses. Rock phosphate may be used with VAM citrus to substitute for medium amounts of soluble phosphate.     

Effect of arbuscular mycorrhizal fungi, organic fertilizer and soil sterilization on maize growth

The effects of inoculation with arbuscular mycorrhizal (AM) fungi, organic fertilizer (F) applications, and soil sterilization on maize growth were evaluated in a pot experiment. The experiment was in a completely randomized factorial design (2 × 4 × 2) with six replicates for each treatment. There were two soil treatments (sterilized soil, SS and unsterilized soil, US), four organic fertilizer treatments (0.0, 0.5, 1.0 and 2.0 g kg^?1 soil), and two AM fungi treatments (inoculation with Glomus mosseae, +AM and uninoculated control, ?AM). Inoculated plants generally had greater AM colonization, plant height, dry weight and phosphorus (P) uptake than uninoculated controls, and these parameters were significantly increased as the organic fertilizer application increased up to 0.5 g kg^?1 but decreased or had no significant effect compared to the uninoculated plants at the highest fertilizer rate (2.0 g kg^?1). Plant growth, P uptake and AM colonization of root system were significantly higher in sterilized soil compared to the unsterilized control. Our results indicated that the inoculation of AM fungi in field soil with optimal organic fertilizer application greatly improved maize growth and nutrient uptake, and the effect was greater under sterilized soil condition.     

水分胁迫下AM真菌对沙打旺生长和抗旱性的影响

利用盆栽试验研究了水分胁迫条件下接种AM真菌对优良牧草和固沙植物沙打旺(Astragalus adsurgens Pall.)生长和抗旱性的影响。在土壤相对含水量为70%、50%和30%条件下,分别接种摩西球囊霉(Glomus mosseae)和沙打旺根际土著菌,不接种处理作为对照。结果表明,水分胁迫显著降低了沙打旺植株(无论接种AM真菌与否)的株高、分枝数、地上部干重和地下部干重,并显著提高了土著AM真菌的侵染率,对摩西球囊霉的侵染率无显著影响。接种AM真菌可以促进沙打旺生长和提高植株抗旱性,但促进效应因土壤含水量和菌种不同而存在差异。不同水分条件下,接种AM真菌显著提高了植株菌根侵染率、根系活力、地下部全N含量和叶片CAT活性。土壤相对含水量为30%和50%时,接种株地上部全N、叶片叶绿素、可溶性蛋白、脯氨酸含量和POD活性显著高于未接种株;接种AM真菌显著降低了叶片MDA含量;接种土著AM真菌的植株株高、分枝数、地上部和地下部干重显著高于未接种株。土壤相对含水量为30%时,接种AM真菌显著增加了地上部全P含量和叶片相对含水量;接种摩西球囊霉的植株株高、分枝数、地上部和地下部干重显著高于未接种株。水分胁迫40d,接种AM真菌显著提高了叶片可溶性糖含量。水分胁迫80d,接种株叶片SOD活性显著增加。菌根依赖性随水分胁迫程度增加而提高。沙打旺根际土著菌接种效果优于摩西球囊霉。水分胁迫和AM真菌的交互作用对分枝数、菌根侵染率、叶片SOD、CAT和POD活性、叶绿素、脯氨酸、可溶性蛋白、地上部全N和全P、地下部全N和根系活力有极显著影响,对叶片丙二醛和地下部全P有显著影响。AM真菌促进根系对土壤水分和矿质营养的吸收,改善植物生理代谢活动,从而提高沙打旺抗旱性,促进其生长。试验结果为筛选优良抗旱菌种,充分利用AM真菌资源促进荒漠植物生长和植被恢复提供了依据。     

Effect of arbuscular mycorrhizal fungi, organic fertilizer and soil sterilization on maize growth ☆

The effects of inoculation with arbuscular mycorrhizal (AM) fungi, organic fertilizer (F) applications, and soil sterilization on maize growth were evaluated in a pot experiment. The experiment was in a completely randomized factorial design (2 × 4 × 2) with six replicates for each treatment. There were two soil treatments (sterilized soil, SS and unsterilized soil, US), four organic fertilizer treatments (0.0, 0.5, 1.0 and 2.0 g kg^-1 soil), and two AM fungi treatments (inoculation with Glomus mosseae, +AM and uninoculated control, －AM). Inoculated plants generally had greater AM colonization, plant height, dry weight and phosphorus (P) uptake than uninoculated controls, and these parameters were significantly increased as the organic fertilizer application increased up to 0.5 g kg^-1 but decreased or had no significant effect compared to the uninoculated plants at the highest fertilizer rate (2.0 g kg^-1). Plant growth, P uptake and AM colonization of root system were significantly higher in sterilized soil compared to the unsterilized control. Our results indicated that the inoculation of AM fungi in field soil with optimal organic fertilizer application greatly improved maize growth and nutrient uptake, and the effect was greater under sterilized soil condition.     

Effect of arbuscular mycorrhizal fungi inoculation of rice seedlings at the nursery stage upon performance in the paddy field and greenhouse

We examined the effect of arbuscular mycorrhizal fungi inoculation at the nursery stage on the growth and nutrient acquisition of wetland rice (t Oryza sativa L.) under field and pot conditions. Seedlings were grown on -ray sterilized paddy soil in two types of nurseries, namely dry nursery and wet nursery, with or without arbuscular mycorrhizal fungi (AMF) inoculation which was a mixture of indigenous AMF (t Glomus spp.) spores collected from the paddy field. Five-to-six week old seedlings were transplanted to the unsterilized soil under field and pot, respectively. Mycorrhizal seedlings had higher shoot biomass under both nursery conditions 5 weeks after sowing. Mycorrhizal colonization and sporulation were 2 to 3 times higher in the dry nursery than the wet nursery at the transplanting stage. Mycorrhizal colonization of plants inoculated in the nursery remained higher than those not inoculated under both field and pot conditions. Sporulation after transplanting to field conditions was about 10 times higher than in the pot. Inoculated plants produced higher biomass at maturity under field conditions, and the grain yield was 14-21% higher than those not inoculated. Conversely, grain yield and shoot biomass were not significantly influenced by AMF colonization under pot conditions. For plants originating from the dry nursery, N, P, Zn and Cu concentrations of field-grown plants at harvest were significantly increased by preinoculation with AMF over those left uninoculated. We conclude that the AMF inoculation at the nursery stage under both dry and wet conditions increased growth, grain yield and nutrient acquisition of wetland rice under field conditions.     

Phosphorus,arbuscular mycorrhizal fungi and performance of the wetland plant Lythrum salicaria L. under inundated conditions

The role of arbuscular mycorrhizal (AM) fungi in aquatic and semi-aquatic environments is poorly understood, although they may play a significant role in the establishment and maintenance of wetland plant communities. We tested the hypothesis that AM fungi have little effect on plant response to phosphorus (P) supply in inundated soils as evidenced by an absence of increased plant performance in inoculated (AM+) versus non-inoculated (AM-) Lythrum salicaria plants grown under a range of P availabilities (0-40 mg/l P). We also assessed the relationship between P supply and levels of AM colonization under inundated conditions. The presence of AM fungi had no detectable benefit for any measures of plant performance (total shoot height, shoot dry weight, shoot fresh weight, root fresh weight, total root length or total root surface area). AM+ plants displayed reduced shoot height at 10 mg/l P. Overall, shoot fresh to dry weight ratios were higher in AM+ plants although the biological significance of this was not determined. AM colonization levels were significantly reduced at P concentrations of 5 mg/l and higher. The results support the hypothesis that AM fungi have little effect on plant response to P supply in inundated conditions and suggest that the AM association can become uncoupled at relatively high levels of P supply.     

Growth responses and dependence of Acacia nilotica var. cupriciformis on the indigenous arbuscular mycorrhizal consortium of a marginal wasteland soil

 The responses of Acacia nilotica L. var. cupriciformis to phosphorus application and inoculation with the indigenous consortium of arbuscular mycorrhizal (AM) fungi were evaluated in a nursery experiment using soil from a marginal wasteland. A positive growth response to mycorrhizal inoculation was observed at an Olsen-P level of 20 ppm in the presence of the natural population of AM fungi. There was growth stimulation by either inoculation or additional P at the highest soil P of 40 ppm. Colonization was negatively correlated to soil P but P content of both shoot and root were positively correlated. Inoculation with the indigenous AM consortium significantly increased the uptake of P at all levels of applied P. Acacia is moderately dependent upon the AM symbiosis and exhibited a maximal mycorrhizal dependence (MD) of 18.25% at 20 ppm Olsen-P level under the conditions studied. A sharp and considerable reduction in MD and dry matter yield observed at 40 ppm P suggests that the external P requirement for maximal production of biomass was met at approximately 20 ppm Olsen-P. Accepted: 25 June 1996     

Growth and nutrition of mycorrhizal guayule plants*

Synthesis of mycorrhiza in guayule plants was achieved by inoculation of 8-day-old seedlings with hyphae and chlamydospores of an undescribed Glomus species. There was a five-fold increase in total dry weight of 30-day-old mycorrhizal- compared to nonmycorrhizal-guayule grown in sterile loamy-sand without additional fertiliser. Thirty-day-old, inoculated- and uninoculated-seedlings were transplanted to sterile or unsterile soil and grown an additional 60 days. The greatest total dry weight of guayule was attained by inoculated transplants grown in sterile soil. Inoculated transplants increased two- to three-fold in total dry weight compared to uninoculated transplants, both grown in unsterile soil. After 90 days, uninoculated plants grown in unsterile soil had formed mycorrhizae with resident vesicular-arbuscular mycorrhizal fungi to the same extent as inoculated-plants grown in unsterile soil. Total mineral uptake increased in inoculated guayule, irrespective of soil treatment or the presence of resident VA mycorrhizal fungi.     

Contribution of the saprobic fungi Trametes versicolor and Trichoderma harzianum and the arbuscular mycorrhizal fungi Glomus deserticola and G. claroideum to arsenic tolerance of Eucalyptus globulus

The presence of high concentrations of arsenic (As) decreased the shoot and root dry weight, chlorophyll and P and Mg content of Eucalyptus globulus colonized with the arbuscular mycorrhizal (AM) fungi Glomus deserticola or G. claroideum, but these parameters were higher than in non-AM plants. As increased the percentage of AM length colonization and succinate dehydrogenase (SDH) activity in the root of E. globulus. Trichoderma harzianum, but not Trametes versicolor, increased the shoot and root dry weight, chlorophyll content, the percentage of AM root length colonization and SDH activity of E. globulus in presence of all As concentrations applied to soil when was inoculated together with G. claroideum. AM fungi increased shoot As and P concentration of E. globulus to higher level than the non-AM inoculated controls. The contribution of the AM and saprobe fungi to the translocation of As from root to shoot of E. globulus is discussed.     

Growth and survival of seedlings of native plants in an impoverished and highly disturbed soil following inoculation with arbuscular mycorrhizal fungi

We investigated whether arbuscular mycorrhizas influenced growth and survival of seedlings in an extremely impoverished and highly disturbed soil. Seedlings of four plants species native to the site were either inoculated with native sporocarpic arbuscular mycorrhizal (AM) fungi or fertilised prior to transplanting, and followed over 86 weeks at the site. One treatment was also irrigated with N-rich leachate from the site. In a laboratory experiment, seedlings were fertilised with excess P for 6 weeks, and location of the P store determined. Growth and survival of AM and fertilised seedlings were similar at the site. Inoculated mycorrhizal fungi and roots appeared to extend into the surrounding soil together. P concentration in leaves of all plants was extremely low. Irrigation with leachate increased growth of seedlings. In the laboratory experiment, significantly more P was stored in roots than shoots. We suggest that successful revegetation of extremely disturbed and impoverished sites requires selection of mycorrhizal fungi and plants to suit the edaphic conditions and methods of out-planting.     

Response of cassava to VA mycorrhizal inoculation and phosphorus application in greenhouse and field experiments

Cassava (Manihot esculenta Crantz) was grown in the greenhouse and in the field at different levels of phosphorus applied, with or without inoculation with VA mycorrhiza in sterilized or unsterilized soil. When grown in a sterilized soil to which eight levels of P had been applied the non-inoculated plants required the application of 3200 kg P ha⁻¹ to reach near-maximum yield of plant dry matter (DM) at 3 months. Inoculated plants, however, showed only a minor response to applied P. Mycorrhizal inoculation in the P check increased top growth over 80 fold and total P uptake over 100 fold. Relating dry matter produced to the available P concentration in the soil (Bray II), a critical level of 15 ppm P was obtained for mycorrhizal and 190 ppm P for non-mycorrhizal plants. This indicates that the determination of critical levels of P in the soil is highly dependent on the degree of mycorrhizal infection of the root system. In a second greenhouse trial with two sterilized and non-sterilized soils it was found that in both sterilized soils, inoculation was most effective at intermediate levels of applied P resulting in a 15–30 fold increase in DM at 100 kg P ha⁻¹. In the unsterilized soil inoculation had no significant effect in the quilichao soil, but increased DM over 3 fold in the Carimagua soil, indicating that the latter had a native mycorrhizal population less effective than the former. When cassava was grown in the field in plots with 11 levels of P applied, uninoculated plants grown in sterilized soil remained extremely P deficient for 4–5 months after which they recuperated through mycorrhizal infection from unsterilized borders or subsoil. Still, after 11 months inoculation had increased root yields by 40%. In the non-sterilized soil inoculation had no significant effect as the introduced strain was equally as effective as the native mycorrhizal population. These trials indicate that cassava is extremely dependent on an effective mycorrhizal association for normal growth in low-P soils, but that in most natural soils this association is rapidly established and inoculation of cassava in the field can only be effective in soils with a low quantity and quality of native mycorrhiza. In that case, plants should be inoculated with highly effective strains.     

Influence of soil impoverishment on the interaction between Glomus mosseae and saprobe fungi

 The effect of the saprobe fungi Wardomyces inflatus (Marchal) Hennebert, Paecilomyces farinosus (Holm & Gray) A. H. S. Brown & G. Sm., Gliocladium roseum Bain., Trichoderma pseudokoningii Rifai and T. harzianum Rifai, isolated from sporocarps of Glomus mosseae, on arbuscular mycorrhizal (AM) colonisation and plant dry matter of soybean was studied in 2/3 and 1/5 diluted soils in a greenhouse trial. Soil dilution to 1/5 had no effect on shoot dry matter of soybean but decreased AM colonisation and root dry weight of plants. CFU of saprobe fungi, except T. harzianum, were higher in 1/5 than in 2/3 diluted soils. W. inflatus and Gliocladium roseum decreased the shoot dry weight of soybean plant when inoculated together with Glomus mosseae. The saprobe fungi P. farinosus and T. pseudokoningii increased the shoot dry weights of plants grown in 1/5 diluted soil. The shoot dry weight and AM colonisation in 1/5 diluted soil were also increased when T. harzianum was inoculated together with Glomus mosseae. Thus, saprobe fungi increased AM colonisation of soybean plants by indigenous endophytes. The AM colonisation of plants at both soil dilutions was increased by Glomus mosseae. The highest level of AM colonisation was observed when P. farinosus and T. pseudokoningii were inoculated together Glomus mosseae. The dilution of soils influenced the interaction between inoculated microorganisms and their effect on plant growth. Accepted: 7 June 1999     

矿区分离丛枝菌根真菌对万寿菊吸Cd潜力影响

盆栽试验研究土壤不同施Cd水平(0、5、20、50μg/g)下,接种矿区污染土壤中丛枝菌根真菌对万寿菊根系侵染率、植株生物量及Cd吸收与分配的影响。结果表明:接种丛枝菌根真菌显著提高Cd胁迫下万寿菊的根系侵染率和植株生物量;随着施Cd水平提高,各处理植株Cd浓度显著增加。各施Cd水平下万寿菊地上部Cd吸收量远远高于根系Cd吸收量,在土壤施Cd量达到50μg/g时,接种处理地上部Cd吸收量是根系的3.48倍,对照处理地上部Cd吸收量是根系的1.67倍;同一施Cd水平下接种处理植株Cd吸收量要显著高于对照。总体上,试验条件下污染土壤中分离的丛枝菌根真菌促进了万寿菊对土壤中Cd的吸收,并在一定程度上增加Cd向地上部分的运转,表现出植物提取的应用潜力。     

Effect of an AM fungal consortium and Pseudomonas on the growth and nutrient uptake of Eucalyptus hybrid

 Eucalyptus is an important tree species used for afforestation of large tracts of marginal and wastelands. Eucalyptus-arbuscular mycorrhizal fungal (AMF) interactions in seedling establishment and growth promotion have been inadequately dealt with. Efforts were made to assess the role of AMF-pseudomonad (PRS9, plant growth promotory fluorescent Pseudomonas) interactions in growth promotion and nursery establishment of E. hybrid. Seedlings were subjected to six different treatments: (i) uninoculated control, (ii) 400 AM spores, (iii) 800 AMF spores, (iv) PRS9 (v) 400 AMF spores + PRS9, (vi) 800 AMF spores + PRS9, with the different P regimes of 10, 20 and 30 ppm. Root length, shoot length, root and shoot fresh and dry weights were maximal at 400 AMF spores and 20 ppm soil P. Shoot P content was maximal at 800 AMF spores followed by 400 AMF spores and 400 AMF spores + PRS9. In general, plant growth was greater at 20 ppm P. Root P content increased significantly with 400 AMF spores followed by 800 at 20 ppm P. Independent of soil P levels, the quality index of mycorrhizal treatments without PRS9 was significantly higher than the treatments including PRS9 or PRS9 alone. Mycorrhizal inoculation efficiency was superior at 10 ppm P irrespective of the treatment. AM alone (400 spores) significantly improved the inoculation efficiency. PRS9 in association with AM fungi inhibited growth promotion and nutrient uptake Accepted: 8 September 1999     

Response of cowpea (Vigna unguiculata) to inoculation with VA-mycorrhizal fungi and to rock phosphate fertilization in some unsterilized Nigerian soils

Summary The effects on cowpea of inoculation with vesicular-arbuscular (VA) mycorrhizal fungi and rock phosphate (RP) fertilization were studied in pots using Alagba and Araromi series soils and in the field on Alagba, Apomu and Egbeda series soils. Inoculation of the plants with VA-mycorrhizal fungi caused very rapid infection of the roots. A higher per cent mycorrhizal infection was maintained during subsequent plant growth in the field. RP application reduced the degree of infection without affecting plant growth in the field and in pot experiments. Nodulation, nitrogen fixation and utilization of RP were increased by inoculation with mycorrhizal fungi in the pot experiments but not in the field experiments. In the pot experiments, inoculated plants supplied with RP flowered earlier, and took up more phosphorus than either inoculated plants without RP or uninoculated plants. The largest response to inoculation in terms of shoot dry matter, nodule yield and nitrogen content of shoots was obtained in Alagba soil under both pot and field conditions.IITA Journal Series Paper No. 136.     

Effectiveness of arbuscular mycorrhizal fungi in phytoremediation of lead- contaminated soil by vetiver grass

A greenhouse experiment was conducted to evaluate the effectiveness of arbuscular mycorrhizal (AM) fungi in phytoremediation of lead (Pb)-contaminated soil by vetiver grass. Experiment was a factorial arranged in a completely randomized design. Factors included four Pb levels (50, 200, 400, and 800 mg kg^?1) as Pb (NO₃)₂, AM fungi at three levels (non mycorrhizal (NM) control, Rhizophagus intraradices, Glomus versiforme). Shoot and root dry weights (SDW and RDW) decreased as Pb levels increased. Mycorrhizal inoculation increased SDW and RDW compared to NM control. With mycorrhizal inoculation and increasing Pb levels, Pb uptake of shoot and root increased compared to those of NM control. Root colonization increased with mycorrhizal inoculation but decreased as Pb levels increased. Phosphorus concentration and uptake in shoot of plants inoculated with AM fungi was significantly higher than NM control at 200 and 800 mg Pb kg^?1. The Fe concentration, Fe and Mn uptake of shoot in plants inoculated with Rhizophagus intraradices in all levels of Pb were significantly higher than NM control. Mycorrhizal inoculation increased Pb extraction, uptake and translocation efficiencies. Lead translocation factor decreased as Pb levels increased; however inoculation with AM fungi increased Pb translocation.     

Alleviation of salt stress by arbuscular-mycorrhizal Glomus species in Lactuca sativa plants

Improved salt tolerance of mycorrhizal plants is commonly attributed to their better mineral nutrition, particularly phosphorus. However, the effect of arbuscular-mycorrhizal (AM) fungi on salt tolerance may not be limited to this mechanism. We investigated the possibility that non-nutritional effects of AM fungi, based on proline accumulation or increased photosynthesis and related parameters, can influence the tolerance of lettuce (Lactuca sativa L.) to salinity. Three levels of salt (3, 4 and 5 g NaCl kg^-1 dry soil) were applied and plants were maintained under these conditions for 7 weeks. The salt-treated AM plants produced greater root and shoot dry weights than unfertilized or P-fertilized non-AM controls. With increasing salinity, both shoot and root dry weights were reduced, but this decrease was greater in uninoculated plants. In particular, shoot dry weight was not reduced in G. fasciculatum-colonized plants as a consequence of salt, whereas in uninoculated plants it was reduced by about 35% at the highest salt level. Proline accumulation was considerably lower for P-amended non-AM and for AM plants except for G. mosseae-colonized plants than was the case for unamended plants. Transpiration, carbon dioxide exchange rate (CER), stomatal conductance and water use efficiency (WUE) were higher in mycorrhizal plants. At 5 g NaCl kg^-1, both photosynthesis and WUE increased by more than 100% in mycorrhizal treatment relative to uninoculated plants. The contents of phosphorus of P-fertilized non-AM plants was similar to or higher than those of G. mosseae- and G. fasciculatum-colonized plants. Plants colonized by G. deserticola had the highest P-content regardless of salt level. Hence, the effect of G. mosseae and G. fasciculatum on salt tolerance in this experiment could not be attributed to a difference in the P content. The mechanisms by which these two fungi alleviated salt stress appeared to be based on physiological processes (increased CER, transpiration, stomatal conductance and WUE) rather than on nutrient uptake (N or P).     

丛枝菌根真菌对郁金香生长及其切花生理的影响

为认识丛枝菌根真菌（arbuscular mycorrhizal fungi,AMF）对郁金香Tulipa gesneriana生长、光合特性以及切后瓶插期生理的影响,通过温室盆栽接种试验,以摩西斗管囊霉Funneliformis mosseae和幼套近明球囊霉Claroideoglomus etunicatum分别单独接种和共同接种,进行温室盆栽实验。结果表明,共同接种F. mosseae和C. etunicatum的郁金香叶片叶绿素a含量、叶绿素b含量和总叶绿素含量均显著高于不接种对照,分别增加了32%、18%和28%。与不接种对照相比,接种AMF处理的郁金香叶片的净光合速率、气孔导度、胞间CO₂浓度和蒸腾速率均显著提高,共同接种F. mosseae和C. etunicatum的郁金香在正午12点达到光合参数最大值。接种AMF处理的郁金香花葶长、地上干物质质量、地上鲜物质质量和叶面积均高于不接种对照,开花期早于不接种对照。切花瓶插期间,接种AMF处理的郁金香切花花瓣可溶性糖含量、可溶性蛋白质含量、超氧化物歧化酶（SOD）和过氧化物酶（POD）等抗氧化酶活性比不接种对照显著提高;且降低了膜脂过氧化产物丙二醛（MDA）含量和相对电导率。接种处理有效地改善切花花枝的水分平衡,并延长郁金香切花的瓶插寿命、最佳观赏期和花期。     

Uptake of 32P from labelled organic matter,by mycorrhizal and non-mycorrhizal subterranean clover (Trifolium subterraneum L.)

An experiment was designed to study whether hyphae and colonized roots of arbuscular mycorrhiza have more direct access to P in organic matter than roots of non-mycorrhizal plants. Soil supplied with 0, 15 or 45 mg P kg^–1 was uniformly mixed with ³²P-labelled organic matter at four levels (0, 1, 2 and 5 g kg^–1) and inoculated with a mycorrhizal fungus or left uninoculated. Pots were incubated at 60% of field capacity for one week prior to sowing of clover, and plants were harvested after a growth period of 23 days. Mycorrhizal colonization increased shoot dry weight, P concentration and ³²P uptake at all P levels. Specific activity in plants was consistently higher than in corresponding soil. This indicates that the added ³²P never reached an equilibrium with inorganic P in the soil. P mineralized from organic matter thus had a residence time in the soil solution sh ort enought to partially avoid isotopic exchange and adsorption. Mycorrhizal colonization influenced specific activity of ³²P in plants from three of the nine combinations of P and labelled organic matter: At the lowest level of P the specific activity was highest in non-mycorrhizal plants, and at the intermediate level of P there was one treatment where mycorrhizal plants had the highest specific activity. These differences are discussed. Plant dry weight and P concentration did not respond to addition of organic matter, though soil extracts consistently contained higher amounts of inorganic P as a result of organic matter addition. The results suggest that mycorrhizal plants at an early growth stage utilize a substantially higher amount of P released from organic matter than non-mycorrhizal plants. This mycorrhizal advantage does not seem to be related to a mycorrhizal influence on mineralization.