Influence Of Mycorrhizal Inoculation Research Articles

Mycorrhization alters root morphology, leaf starch and nutrient content of micropropagated banana under water stress

The influence of mycorrhizal inoculation under water stress was studied to observe the effect of different mycorrhizal strains on the root morphology in banana and its consequence on starch and nutrient content of in vitro derived banana leaves. We assessed per cent root colonization, number of roots per plant, root length, root fresh weight, root dry weight and its effect on leaf starch content of micropropagated banana plantlets during hardening at 20, 40 and 60 days after mycorrhizal inoculation. The effect of mycorrhization on leaf nutrient (N, P, and K) was recorded at the end of the hardening period. Four treatments including control were replicated four times and 10 plants per replication were maintained in completely randomized design (CRD). Significant increase in number of roots, root fresh and dry weight of mycorrhized banana plantlets was recorded at 20, 40 and 60 days after inoculation over control. Though the numbers of roots remain significantly less in banana plantlets without mycorrhization, the root length was highest throughout the experimental period. Changes in root morphology of mycorrhized plantlets under water stress plays an important role in improved growth as number of lateral roots increase surface area for nutrient and water absorption. Significantly less leaf starch content after 20 days of inoculation in mycorrhizal plantlets were observed which increased significantly after 40 days of inoculation and continued up to 60 days. Foliar N, P, K content was also found to be significantly high in the mycorrhizal plantlets as compared to non-mycorrhized plantlets at 60 days after inoculation.

Influence of mycorrhizal inoculation on carrot growth, metabolites and nutrition

ABSTRACTMycorrhizae are fungal symbionts forming mutualistic relationships with plant roots. This study was undertaken to evaluate the overall influence of arbuscular mycorrhizal fungi (AMF) on the overall growth and development of carrot plant. Surface-sterilized seeds of carrot were sown in earthen pots filled with sterile soil. Half of the pots were inoculated with AMF spores; the other half without any AMF inoculation represented control. After germination inoculated plants, along with the controls, were sampled at 20, 40, 60 and 80 days of growth after seedling emergence. There is a progressive net increase in growth with each 20-day interval after seedling emergence. Storage roots of carrot had a higher level of metabolites and nutrients like nitrogen, phosphorus and potassium in mycorrhiza colonized plants than the control. High performance liquid chromatography analysis indicated an increase in the carbohydrate fractions in AMF-inoculated roots. Thus, mycorrhiza has been found increasing the growth, metabolites and nutrition of carrot plant.

Olive mycorrhization: Influences of genotype, mycorrhiza, and growing periods

The influence of mycorrhizal inoculation using two arbuscular mycorrhizal fungal species including Glomus mosseae and G. intraradices on some growth traits and phytochemicals of olive plantlets cultivars Koroneiki and Valanolia during 20–80 weeks after inoculation was studied. The results revealed that Valanolia had higher leaf area than Koroneiki, while Koroneiki had higher height, more number of lateral shoots and leaves, higher content of phenol and higher root colonization. There was no significant difference in leaf content of total chlorophylls and carotenoids between the cultivars. The fungal species did not show any significant difference in the traits studied, except for the percentage of root colonization, which was higher in the plantlets inoculated with G. intraradices. However, both the arbuscular mycorrhizal treatments significantly increased the plantlets height, stem diameter, number of lateral shoots and leaves, internode length, and leaf total phenols, chlorophylls and carotenoids. In contrast, they had no significant influences on leaf area. Among the attributes measured in this experiment, internode length, leaf area, total phenols and carotenoids did not change during the growing periods, while the other traits showed an increase from 20 to 80 weeks after inoculation. The positive effects of mycorrhiza inoculation observed in the present study may be beneficial and applicable to the commercial olive nurseries.

Influence of mycorrhizal inoculation on growth of micropropagated Populus × canescens lines in metal-contaminated soils

Micropropagated grey poplar (Populus × canescens (Aiton) Sm.) plantlets selected during in vitro culture as tolerant to toxic Cu and Pb ions, as well as control plantlets, were inoculated ex vitro with selected strains of ectomycorrhizal fungi (Hebeloma crustuliniforme, Paxillus involutus) and an arbuscular mycorrhizal fungus (Rhizophagus irregularis BEG 87) or not inoculated, and were grown for 8 weeks in a growth chamber. Successfully acclimatized microplants were transferred to a greenhouse and grown for 16 weeks in unpolluted soil irrigated during the cultivation period with solutions containing high concentrations of Cu or Pb ions or in soil contaminated with Cu and Pb collected 1 km from a copper smelter. Ectomycorrhizal inoculation enhanced the survival rate of plantlets during ex vitro acclimatization. Poplar microplants inoculated with H. crustuliniforme and selected strains of P. involutus accumulated higher concentrations of Cu and Pb when grown in contaminated soils than the uninoculated plants and reduced concentration of the metals in the soils. In conclusion, grey poplar microplants tolerant to heavy metals and inoculated with appropriate ectomycorrhizal fungi can facilitate the adaptation of these plants to metal-polluted soils and may be used for afforestation and phytoremediation of polluted land.

Influence of mycorrhizal inoculation on the accumulation and speciation of selenium in maize growing in selenite and selenate spiked soils

Abstract Effects of inoculation with arbuscular mycorrhizal (AM) fungus Glomus mosseae on the accumulation and speciation of selenium (Se) in maize were systematically investigated using soil spiked with selenite (Se(IV)) and selenate (Se(VI)). Selenium speciation was analyzed by HPLC–ICP-MS. The results indicated that accumulation and speciation of Se in plants and the influence of mycorrhizal inoculation depend on the chemical form of Se that the soil was spiked with. There was no obvious influence of inoculation on Se species distribution, plant uptake and translocation for the experimental treatment that was supplied with Se(VI). When Se(IV) was supplied to the soil, mycorrhizal inoculation promoted oxidation of Se(IV) to Se(VI) in the soil, inhibited Se accumulation by maize, enhanced the accumulation of Se(VI) but reduced the accumulation of organic Se in maize. Microbeam X-ray fluorescence (μ-XRF) mapping confirmed that mycorrhizal inoculation inhibited the translocation of Se from the surface to the inner of roots when Se(IV) was added to soil. This study elucidates, for the first time, the speciation-dependent influence of mycorrhizal inoculation on the behavior of Se in the soil–plant system.

The influence of mycorrhizal inoculation and paclobutrazol on water and nutritional status of Arbutus unedo L.

The purpose of this study was to analyze morphological and physiological aspects of Arbutus unedo L. plants treated with paclobutrazol (PAC), compounds characterized by their double activity as plant growth regulators and fungicides, and the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch, which forms a special type of mycorrhizal colonization called arbutoid mycorrhiza. Native A. unedo L. seedlings were grown in a greenhouse and subjected to four treatments for 4 months: 0 or 60 mg of PAC and inoculated or not with P. tinctorius (Pers.) . The arbutoid mycorrhizal inoculation increased in plants treated with PAC. Paclobutrazol reduced shoot and root biomass, plant height, internode length, stem diameter, leaf area, total root length and number of tips. P. tinctorius increased plant height and had a beneficial effect on the root system (increasing root diameter and the number of tips). PAC treatment led to an increase in ion levels in the leaf tissue, while mycorrhizal inoculation induced lower K and higher P contents in the roots. Leaf water potentials (at predawn and at midday) increased with the combined treatment. The absence of water deficit conditions meant there was no osmotic adjustment. Higher photosynthesis ( P n) values were associated with higher stomatal conductance ( g s) values in the mycorrhizal plants, which influenced water uptake from the roots. However, g s decreased in the PAC-treated plants, reducing photosynthesis and, as a consequence, growth. The higher hydraulic conductivity ( L p) in the plants treated with PAC may have induced a better water energy status and good water transport. The combined treatment produced beneficial effects in the plants, improving their water and nutritional status.

Influence of mycorrhizal inoculation on alley cropped farms in a humid tropical environment

The use of Arbuscular mycorrhizal (AM) fungi under farmers' conditions was tried at Ajibode Village, a humid tropical environment on maize/cassava intercropped farms in an alley cropping system. Four species of AM fungi ( Glomus clarum, Glomus mosseae Glomus etunicatum and Acaulospora dilatata ) were used in paired treatment experimental design. Cassava and maize yields on the inoculated plots were higher than the control. It was also found that G. etunicatum was more efficient for cassava while G. mosesae was more efficient for maize. The study concluded that AM fungi inoculation can be easily adopted by farmers in the humid tropics as a low external input sustainable agricultural technology. Key words: Abuscular Mycorrhiza; Fungi; Glomus clarum; Glomus mosseae; Glomus etunicatum; Acaulospora dilatata Moor Journal of Agricultural Research Vol.4(2) 2003: 246-250

Influence of mycorrhizal inoculation and different pruning regimes on fresh root yield of alley and sole cropped cassava (manihot esculenta crantz) in Nigeria

The effect of mycorrhizal fungus inoculation on fresh root yield of cassava (Manihot esculenta crantz) cv TMS 4 (2) 1425 as influenced by two hedgerow tree species and their mixtures, subjected to 2- and 3-month pruning regimes were investigated in alley cropping experiments at three different sites within the same eco-climatic region in Nigeria. Mixture of the prunings of the two hedgerow tree species (Gliricidia sepium and Senna siamea) with mycorrhiza gave higher fresh root yield than the sole hedgerow tree with mycorrhizal inoculation. Gliricidia sepium prunings were found to give higher fresh root yield than the prunings from the Senna siamea. The 2-month prunings of G. sepium recorded higher yield than its 3-month prunings while 2-month prunings of Senna siamea recorded higher yield than its 3-month prunings. However, mycorrhiza inoculation with 2- and 3-month prunings in the two hedgerow species used were found higher than their counterparts without mycorrhizal inoculation in all the three sites. Mycorrhizal inoculation without the hedgerow prunings recorded the lowest fresh root yield but was still higher than the fresh root yield from the sole without mycorrhizal inoculation. Thus, inoculation with mycorrhiza increased alley-cropped cassava fresh root yield over uninoculated plants under both pruning regimes. Generally, this study shows that inoculation of cassava with mycorrhiza alone without mulching with prunings significantly increased cassava fresh root yield.

Influence of mycorrhizal inoculation on disease severity and growth of pepper ( capsicum annum linn.)

Greenhouse experiment was carried out to investigate the disease severity caused by Phytophthora infestans and how it was suppressed by Glomus etunicatum (mycorrhiza) with its attendant growth effect on Capsicum annum (pepper). Glomus etunicatum (mycorrhiza) greatly reduced the disease severity effect of Phytophthora infestans (pathogen) on pepper seedlings with significant influence on all growth parameters of pepper. Inoculating pepper seedlings with pathogen alone or before inoculating mycorrhiza reduced their height compared to simultaneous and dual inoculations with mycorrhiza. Effect of pathogen was severe on the influorescence of pepper plants while those inoculated with mycorrhiza had the highest flowering and fruiting values. However, when pathogen and mycorrhiza were inoculated either simultaneously or dually, the effect of pathogen was highly suppressed. Also, there was increase in the number of leaves of pepper plants inoculated with mycorrhiza alone than those inoculated with pathogen alone. Results obtained showed that inoculation of Glomus etunicatum before Phytophthora infestans inoculation into pepper seedlings increased their resistance and suppressed the effect of pathogenic infection.