Effect Of Glomus Intraradices Research Articles

Effect of Glomus intraradices on root morphology, biomass production and phosphorous use efficiency of Chinese fir seedlings under low phosphorus stress.

Available phosphorus (P) scarcity in the highly weathered soils of the subtropical forests in southern China is a serious concern. To ensure whether inoculation of arbuscular mycorrhizal fungi (AMF) with Chinese fir (Cunninghamia lanceolata) under low P stress conditions could promote its growth and P utilization capacity, an indoor pot simulation experiment was carried out with the different P supply treatments and Chinese fir seedlings as the tested material. The experiment had two P supply treatments, no P supply (P0, 0 mmol·L-1 KH2PO4) and normal P supply (P1, 1.0 mmol·L-1 KH2PO4). The seedling in each P supply treatment was inoculated with Glomus intraradices (Gi), a widespread species of AMF in the natural environment, and with no AMF inoculation as a control treatment (CK). The Gi infection rate in the root system, root cortex tissue dissolution rate, root morphological indexes and biomass, whole plant P use efficiency, and root P use efficiency of Chinese fir were determined under different treatment conditions. The results showed that P0 treatment significantly increased the Gi infection rate (p< 0.05). After inoculating AMF with different P supply treatments, the root cortex tissue dissolution rate was considerably enhanced. In contrast, the Chinese fir's root length and surface area were reduced; however, the root volume did not change significantly. The average root diameter in the P0 treatment and inoculated with AMF was significantly more prominent than in the uninoculated treatment (p< 0.05). The root biomass and root-to-shoot ratio at different P supply treatments were significantly higher in the Gi infection treatment than in the CK group. Under different P supply treatments, root inoculation with Gi promoted root P use efficiency and whole plant P use efficiency. In conclusion, low P stress condition promoted the colonization of AMF in the root system, increased the dissolution of root cortex tissue, root volume, and the average diameter, and promoted root biomass accumulation and P use efficiency.

Use of microbial inoculants for production of potato tuber seed in greenhouse conditions

Objectives: To determine the effect of Glomus intraradices and Bacillus subtilis on the agronomic performance from in vitro potato seedlings in greenhouse conditions. Methodology: The research was developed in pots under greenhouse conditions at Universidad Nacional José Faustino Sánchez Carrión, Huacho, Lima, from October 2017 to March 2018. The substrate for pots was 45% sand, 45% vermicompost, and 10% rice straw, with an average content of 3% organic matter. The average environmental temperature was 25°C. In vitro seedlings of five potato genotypes were transplanted into 4-liter pots, and inoculated with commercial inoculants of Glomus intraradices, a mixture of G. intraradices + Bacillus subtilis, a fertilization treatment with NPK (220-180-120) and control without inoculation. Completely randomized design with four replications on a factorial arrangement was used, with four inoculant treatments and five potato genotypes. The data of ten agronomic characters, that included the weight of the tubers and biomass per plant, were subjected to analysis of variance and then to tests of mean comparison of Scott-Knott and processed with Infostat software. Results: Inoculation treatments with mycorrhizae or mycorrhizae with rhizobacteria, statistically surpassed (P &lt; 0.05) the controls in the case of weight of tubers per plant, the average weight of tubers, number of tubers per plant and diameter of the tuber, in addition to the height of the plant at 15 and days after the transplant; in the case of fresh foliage weight per plant and the degree of senescence of the foliage, the control treatments statistically surpassed (P &lt; 0.05) to the inoculation treatments. For other characters, number of sprouts per plant, the number of leaves and number of flowers per plant, no significant differences (P &gt; 0.05) was found. Conclusions: The use of microbial inoculants based on mycorrhizae and rhizobacteria, improves the productivity of potato seed tubers under greenhouse conditions.Keywords: Glomus intraradices, agronomic performance, in vitro seedlings, potato varieties, greenhouse

Effect of Glomus intraradices in improving the tolerance of a hybrid family of Theobroma cacao L. against Phytophthora megakarya

Effect of Glomus intraradices in improving the tolerance of a hybrid family of Theobroma cacao L. against Phytophthora megakarya

Effect of Glomus Intraradices on Physiological and Biochemical Traits of Wheat Grown in Nickel Contaminated Soil

ABSTRACTThis study was undertaken to evaluate the role of mycorrhizal fungi application on mitigating adverse effects of nickel (Ni) in wheat. The experiment was conducted using four levels of Ni (0, 60, 120 and 180 mg per kg of soil) and two levels of mycorrhizal fungi application (with and without Glomus intraradices). Ni stress significantly decreased total dry weight per plant and total chlorophyll. By contrast, proline, superoxide dismutase (SOD) enzyme activity, malondialdehyde (MDA), and the accumulation of Ni in the leaves and roots increased on account of Ni treatments. In addition, mycorrhizal fungi application increased total dry weight per plant and total chlorophyll as well as the accumulation of Ni in the roots. Mycorrhizal fungi application could reduce proline, SOD enzyme activity, MDA and the accumulation of Ni in the leaves. In general, the results suggest that mycorrhizal fungi application reduces the harmful effects of Ni stress in wheat.

The effect of Glomus intraradices on the physiological properties of Panax ginseng and on rhizospheric microbial diversity

BackgroundGlomus intraradices is a species of arbuscular mycorrhizal fungi that, as an obligate endomycorrhiza, can form mutually beneficial associations with plants. Panax ginseng is a popular traditional Chinese medicine; however, problems associated with ginseng planting, such as pesticide residues, reduce the ginseng quality. MethodsIn this experiment, we studied the effect of inoculating G. intraradices on several physiological properties and microbial communities of ginseng. UV-Visible Spectrum method was used to detect physical properties. Denaturing gradient gel electrophoresis method was used to analyze microbial communities. ResultsThe results indicated that inoculation with G. intraradices can improve the colonization rate of lateral ginseng roots, increase the levels of monomeric and total ginsenosides, and improve root activity as well as polyphenol oxidase and catalase activities. We also studied the bacterial and fungal communities in ginseng rhizospheric soil. In our study, G. intraradices inoculation improved the abundance and Shannon diversity of bacteria, whereas fungi showed a reciprocal effect. Furthermore, we found that G. intraradices inoculation might increase some beneficial bacterial species and decreased pathogenic fungi in rhizospheric soil of ginseng. ConclusionOur results showed that G. intraradices can benefit ginseng planting which may have some instructive and practical significance for planting ginseng in farmland.

Effects of Glomus intraradices on the drought resistance and growth of corn plant (Zea mays L.)

A pot experiment was carried out at the greenhouse of Faculty of Agriculture (Saba bacha), Alexandria University. The experiment was conducted to investigate the role of Glomus intraradices fungi in the effects on the growth and water requirement of pot-grown corn (Zea mays L.). Four water regimes (20%, 30%, 40% and 50% of the available soil water content) were conducted. The Arbuscular Mycorrhizal Fungi AMF inoculation could significantly increase plant growth (including plant height, leaf area, and fresh and dry mass), enhance relative leaf water content, transpiration rates and stomatal conductance, and improve plant drought tolerance. The water consumption of the mycorrhizal plants producing 1 g of dry matter was 20%–35% of water content conditions. These findings indicate that the mycorrhizae enhanced the water utilization efficiency.

Use of the arbuscular mycorrhizal fungus Glomus intraradices as biological control agent of the nematode Nacobbus aberrans parasitizing tomato

ABSTRACT The plant-parasitic nematode Nacobbus aberrans is an endoparasite that induces gall formation in the roots and causes severe losses to diverse crops. Some populations of this nematode show preference for certain hosts, revealing the existence of “races/groups” with diff erent behaviour and making nematode management difficult. A possible biological control alternative to reduce the damage caused by this species may be the use of arbuscular mycorrhizal fungi (AMF). In the present work, the effect of Glomus intraradices on tomato plants inoculated with the nematode at transplanting and three weeks later was tested. At 60 days, the following parameters were estimated: percentage of AMF colonization, root and aerial dry weight, number of galls and egg masses, and reproduction factor (RF=final population/initial population) of N. aberrans . AMF colonization was higher in the presence of the nematode. The use of AMF favoured tomato biomass and reduced the number of galls and RF on the plants inoculated with the nematode at transplanting. Key words: arbuscular mycorrhiza, false root-knot nematode, microbiological control, plant protection

Effects of Glomus intraradices on the growth and reactive oxygen metabolism of foxtail millet under drought

Foxtail millet (Setaria italica L.) is an ancient domesticated crop grown in arid and semi-arid Africa and Eurasian continent. This study investigated the effects of arbuscular mycorrhizal (AM) fungi (Glomus intraradices) and water stress on the growth and reactive oxygen metabolism of foxtail millet under greenhouse pot conditions. After two soil water availability treatments [well-watered (WW) −0.11 MPa; water-stressed (WS) −0.68 MPa] for 31 days, G. intraradices could colonize well in the roots of foxtail millet. Water stress inhibited AM colonization, plant growth and crop yield, and also increased reactive oxygen metabolism and antioxidant enzyme activities of foxtail millet. G. intraradices-inoculated foxtail millet had greater plant height, collar diameter, panicle heigh, panicle weight and grain weight, higher enzyme activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and glutathione reductase (GR), and lower concentration of malondialdehyde (MDA) , H2O2, and O2 ·-, when compared with non-inoculated foxtail millet under both WW and WS conditions. Our results demonstrated that G. intraradices-inoculated foxtail millet showed higher drought-tolerance by improving their growth and productivity, reactive oxygen species (ROS) and antioxidant enzyme activities, compared with non-inoculated foxtail millet. This indicates that G. intraradices inoculation is a potential method for enhancing the performance of foxtail millet under drought conditions.

Uptake kinetics of different arsenic species in lowland and upland rice colonized with Glomus intraradices

The effect of Glomus intraradices on four As species (arsenate; arsenite; dimethylarsinic acid, DMA; and monomethylarsonic acid, MMA) uptake by lowland rice and upland rice were investigated based on two experiments: (1) high (0–0.05 mM) and low (0–2.5 mM) – affinity uptake kinetics of four As species in the short-term, and (2) As speciation in rice treated with 1 mM arsenate, arsenite, DMA or MMA solutions. The results showed that mycorrhizal roots of two rice cultivars reduced the arsenate uptake significantly ( P < 0.001) in low-affinity uptake system, and decreased the uptake of arsenite and MMA noticeably ( P < 0.05) in high or low-affinity uptake systems. The four As species influx have significant differences ( P < 0.05) between two rice varieties in low-affinity uptake systems. In the arsenate treatment, the ratio of arsenate/arsenite reduced in shoots while increased in roots because of G. intraradices presence.

Effects of Glomus intraradices and onion cultivar on Allium white rot development in organic soils in Ontario

Commercial products containing formulations of the vesicular-arbuscular mycorrhiza (AM) Glomus intraradices were assessed for their effectiveness in suppressing Allium white rot (WR) on onions (Allium cepa) in organic soils and compared with the fungicide Folicur 3.6F (430 g a.i./L tebuconazole) under field conditions. The trials were conducted during 2000 and 2001 in commercial onion fields in the Holland-Bradford Marsh in Ontario. The AM product MIKRO-VAM, which is used in transplanted onions, reduced the incidence of WR by almost 50% compared with the untreated control and was comparable with that of the fungicide treatment, Folicur 3.6F, applied according to label recommendations. This is one of the few studies to demonstrate season-long disease suppression with AM under field conditions, and it is the first to show that the AM products can be as effective as a fungicide treatment under commercial production practices. A consistent difference in incidence of WR was found between the cultivars 'Hoopla'...

Effects of fertilizers, AM fungus and plant growth promoting rhizobacterium on the growth of tomato and on the reproduction of root-knot nematode Meloidogyne incognita

The effects of Glomus intraradices and Pseudomonas putida were observed alone and in combination with fertilizers (composted cow manure and urea) on the growth of tomato and on the reproduction of Meloidogyne incognita. Inoculation of P. putida caused a greater increase in the tomato growth than G. intraradices and inoculation of both together caused a greater increase than by either of them. Use of composted manure was better in increasing tomato growth than urea and high dosage of fertilizers were more effective than low dosage. Composted manure with P. putida and G. intraradices was more beneficial for tomato growth than the use of urea with these microorganisms. Root colonization by G. intraradices and P. putida was increased with composted manure while urea had an adverse effect on root colonization. Pseudomonas putida caused a higher reduction in galling and nematode multiplication than G. intraradices. The maximum reduction in galling and nematode multiplication was observed when P. putida was used with G. intraradices together with composted manure.

Glomus intraradices, Pseudomonas alcaligenes, and Bacillus pumilus: effective agents for the control of root-rot disease complex of chickpea (Cicer arietinum L.)

The effects of Glomus intraradices, Pseudomonas alcaligenes and Bacillus pumilus on the root-rot disease complex caused by the root-knot nematode Meloidogyne incognita and the root-rot fungus Macrophomina phaseolina in chickpea was assessed by quantifying differences in the shoot dry mass, pod number, nodulation, and shoot content of chlorophyll, nitrogen, phosphorus and potassium. Inoculation of plants with G. intraradices, P. alcaligenes and B. pumilus alone and in combination significantly increased shoot dry mass, pod number, and content of chlorophyll, nitrogen, phosphorus and potassium in plants inoculated with pathogens over that in the uninoculated control plants. P. alcaligenes caused a greater increase in shoot dry mass, pod number, chlorophyll, nitrogen, phosphorus and potassium in plants with pathogens than did G. intraradices or B. pumilus. Combined application of G. intraradices, P. alcaligenes and B. pumilus to plants inoculated with pathogens caused a greater increase in shoot dry mass, pod number, nitrogen, phosphorus, and potassium than did an application of P. alcaligenes plus B. pumilus or of G. intraradices plus B. pumilus. Root colonization by G. intrardices was high when used alone, while inoculation with the pathogens reduced root colonization by G. intraradices. In the presence of P. alcaligenes and B. pumilus, root colonization by G. intraradices increased. In plants inoculated with just one antagonist, P. alcaligenes reduced galling and nematode multiplication the most, followed by G. intraradices, then B. pumilus. The greatest reduction in galling, nematode multiplication and root-rot was observed when both bacterial species and G. intraradices were applied together.

Biocontrol of a root-rot disease complex of chickpea by Glomus intraradices, Rhizobium sp. and Pseudomonas straita

The effects of Glomus intraradices, Rhizobium sp. and Pseudomonas straita on the root-rot disease complex of chickpea caused by Meloidogyne incognita and Macrophomina phaseolina were observed. Inoculation of G. intraradices, P. straita and Rhizobium caused a significant increase in plant growth, number of pods, chlorophyll, nitrogen, phosphorus and potassium contents of pathogen-inoculated plants. Inoculation of Rhizobium caused a greater increase in plant growth, number of pods, chlorophyll, nitrogen, phosphorus and potassium contents of pathogen-inoculated plants than caused by P. straita or G. intraradices. Combined inoculation of G. intraradices with P. straita plus Rhizobium to pathogen-inoculated plants caused greater increase in plant growth, number of pods, chlorophyll, nitrogen, phosphorus and potassium contents than by inoculation of G. intraradices plus Rhizobium or G. intraradices plus P. straita. The numbers of nodules per root system were significantly higher in plants inoculated with Rhizobium compared with uninoculated ones. Inoculation of Rhizobium with P. straita/G. intraradices further increases nodulation per root system over plants inoculated with Rhizobium alone. Root colonization by G. intraradices was high in plants inoculated alone. In the presence of P. straita and Rhizobium, root colonization by G. intraradices was increased, while inoculation of pathogens reduced colonization by G. intraradices. Inoculation of Rhizobium caused higher reduction in galling and nematode multiplication, followed by P. straita and G. intraradices. Maximum reduction in galling and nematode multiplication was observed when G. intraradices was inoculated with both bacteria. Biocontrol of root-rot disease complex of chickpea may be achieved by the combined use of Rhizobium, G. intraradices and P. straita or use of Rhizobium plus P. straita.

Biocontrol of a chickpea root-rot disease complex withGlomus intraradices,Pseudomonas putidaandPaenibacillus polymyxa

The effect of Glomus intraradices, Pseudomonas putida and Paenibacillus polymyxa on the growth, chlorophyll, nitrogen, phosphorus and potassium contents and on the root-rot disease complex of chickpea (caused by Meloidogyne incognita and Macrophomina phaseolina) were observed. Inoculation of plants with G. intraradices, P. putida and P. polymyxa alone and in combination significantly increased plant growth, pod number, chlorophyll, nitrogen, phosphorus and potassium contents and reduced galling, nematode multiplication and root-rot index. Inoculation of plants with P. putida most effectively reduced galling and nematode multiplication, followed by G. intraradices and P. polymyxa. Combined inoculation of plants with G. intraradices, P. putida and P. polymyxa caused the greatest reduction in galling, nematode multiplication and root-rot index. Pathogens had adverse effects on root colonisation by G. intraradices, while root colonisation by arbuscular mycorrhizal fungus was increased in the presence of P. putida and P. polymyxa.

Effect ofGlomus intraradices isolated from Pb-contaminated soil on Pb uptake byAgrostis capillaris is changed by its cultivation in a metal-free substrate

Development and heavy metal tolerance of two cultivation lineages of the indigenous isolate of arbuscular mycorrhizal fungus (AMF)Glomus intraradices PH5 were compared in a pot experiment in soil from lead (Pb) smelter waste deposits. One lineage was sub-cultured in original Pb-contaminated soil; the second one was maintained for 13 months in an inert substrate (river sand) without Pb stress. The contribution of these cultivation lineages to the Pb uptake and accumulation by the host plantAgrostis capillaris was investigated. The experiment was conducted in a compartmented system where the lateral compartments withAgrostis seedlings were separated from the central pot containing 4-week olderAgrostis plants by a nylon mesh for allowing out-growing of extraradical mycelium (ERM) from the pot.

Effects of Glomus intraradices on the reproduction of the burrowing nematode ( Radopholus similis ) in dixenic culture

The effects of Glomus intraradices on the reproduction of the burrowing nematode Radopholus similis were studied under dixenic culture conditions. The life cycles of both the arbuscular mycorrhizal fungus (AMF) and the nematode were completed in presence of each other and a transformed carrot root as host. The AMF suppressed the R. similis population by almost 50% and thus increased protection of the root against the nematode. This reduction was significant for both females and males within roots. There was no correlation between nematode population density and either AMF internal root colonization, external hyphal development or spore production. These results demonstrate that the dixenic system, although artificial, is a valuable tool for studying AMF–nematode interactions, complementing the classical experimental approaches.