Mycorrhizal roles in plant growth, gas exchange, root morphology, and nutrient uptake of walnuts

Walnut, an important oil fruit tree, is dependent on arbuscular mycorrhizas, while mycorrhizal roles and efficient mycorrhizal fungus in walnuts are unknown. This study was conducted to evaluate the effect of five arbuscular mycorrhizal fungi (AMF) species, including Acaulospora scrobiculata, Diversispora spurca, Glomus etunicatum, G. mosseae, and G. versiforme on plant growth, leaf gas exchange, root morphology, and root nutrient contents of walnut (Juglans regia L. Liaohe 1) seedlings. Three months of AMF inoculations later, root mycorrhizal colonisation achieved 47.0% to 76.4%. AMF treatments increased plant growth performance, dependent on AMF species. AMF-inoculated plants with D. spurca, G. etunicatum, and G. mosseae showed higher root length, projected area, surface area, and volume than non-AMF plants. Except for G. versiforme, the other four AMF treatments almost significantly increased leaf photosynthesis rate, transpiration rate, and stomatal conductivity, while reduced intercellular CO<sub>2</sub> concentrations and leaf temperature. AMF affected root nutrient contents, dependent on AMF and mineral nutrient species. These results, thereby, concluded that AMF had a positive role in walnuts, dependent on AMF species, and D. spurca was the best mycorrhizal fungus for walnut. Such results provide the potential possibility of a developing consortium of AMF in walnut cultivation management.

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Bell Pepper (Capsicum annum L.) Crop as Affected by Shade Level: Microenvironment, Plant Growth, Leaf Gas Exchange, and Leaf Mineral Nutrient Concentration

HortScience ◽

10.21273/hortsci.48.2.175 ◽

2013 ◽

Vol 48 (2) ◽

pp. 175-182 ◽

Cited By ~ 21

Author(s):

Juan Carlos Díaz-Pérez

Keyword(s):

Gas Exchange ◽

Plant Growth ◽

Soil Water ◽

Leaf Area ◽

Leaf Gas Exchange ◽

Bell Pepper ◽

Mineral Nutrient ◽

Specific Leaf Weight ◽

Leaf Weight ◽

Leaf Transpiration

Use of shading nets helps ameliorate heat stress of vegetable crops. This study evaluated the effects of shade level on microenvironment, plant growth, leaf gas exchange, and mineral nutrient content of field-grown bell pepper crop. Bell pepper cultivars Camelot, Lafayette, Sirius, and Stiletto were grown at 0%, 30%, 47%, 62%, and 80% shade levels. Photosynthetically active radiation and air, leaf, and root zone temperatures decreased as shade level increased. Despite having increased plant leaf area, there was increased soil water content with increased shade level, indicating reduced soil water use. With increased shade level, the total plant leaf area, individual leaf area, and individual leaf weight increased, whereas leaf number per plant and specific leaf weight decreased. In contrast to non-normalized chlorophyll index (CI) values, CI normalized by specific leaf weight were related to leaf nitrogen (N) and increased with increased shade level. Net photosynthesis and stomatal conductance (gS) decreased and leaf transpiration increased with increased shade level, particularly above 47% shade level. Leaf concentrations of N, potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), sulfur (S), aluminum (Al), and boron (B) increased with increased shade level. Relatively few differences in plant growth, leaf gas exchange, and leaf mineral nutrient concentrations were observed among cultivars. In conclusion, morphological changes such as taller plants and thinner and larger leaves likely enhanced light capture under shaded conditions compared with unshaded plants. High shade levels reduced leaf temperature and excessive leaf transpiration but resulted in reduced leaf photosynthesis. Thus, moderate shade levels (30% and 47%) were the most favorable for bell pepper plant growth and function.

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Mycorrhiza-induced changes in root growth and nutrient absorption of tea plants

Plant Soil and Environment ◽

10.17221/126/2018-pse ◽

2018 ◽

Vol 64 (No. 6) ◽

pp. 283-289 ◽

Cited By ~ 12

Author(s):

Shao Ya-Dong ◽

Zhang De-Jian ◽

Hu Xian-Chun ◽

Wu Qiang-Sheng ◽

Jiang Chang-Jun ◽

...

Keyword(s):

Plant Growth ◽

Root Hair ◽

Root Morphology ◽

Mycorrhizal Fungi ◽

Nutrient Status ◽

Arbuscular Mycorrhizas ◽

Nutrient Absorption ◽

Positive Effects ◽

Tea Plants ◽

Amf Inoculation

Tea plants grown in acidic soils are strongly dependent on arbuscular mycorrhizas, whereas it is not clear whether soil arbuscular mycorrhizal fungi (AMF) improve plant growth, root development, and nutrient absorption in tea plants. A potted study was conducted to determine the effects of Claroideoglomus etunicatum, Diversispora spurca, D. versiformis and a mixture of the three AMF species on plant growth, root morphology, root-hair growth, and leaf nutrient status in Camellia sinensis cv. Fuding Dabaicha in Jingzhou, China. After 12 weeks of AMF inoculation, root mycorrhizal colonization ranged from 15.12% to 40.23%. AMF inoculation heavily increased plant height, shoot and root biomass, and total leaf area, whilst the increased effect was ranked as C. etunicatum > D. spurca > mixed-AMF > D. versiformis in the decreasing order. Mycorrhizal inoculation also considerably increased total root length and volume, whereas obviously inhibited root-hair length and number, in company with an increment in root-hair diameter. Leaf N, P, K, Ca, Mg, Zn, and Mn contents were significantly higher in AMF-inoculated plants than in non-AMF-inoculated plants, regardless of AMF species. It concludes that AMF inoculation had positive effects on plant growth performance, root morphology, and leaf nutrient levels in cv. Fuding Dabaicha seedlings, whilst C. etunicatum performed the best effects.

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The Effects of Magnetic Treatment On Seedling Growth, Nitrogen Metabolism, And Mineral Nutrient Contents In Populus×Euramericana 'Neva' Under Cadmium Stress

10.21203/rs.3.rs-739553/v1 ◽

2021 ◽

Author(s):

Xiumei Liu ◽

Fengyun Ma ◽

Lu Wang ◽

Hong Zhu ◽

Shiyuan Meng ◽

...

Keyword(s):

Seedling Growth ◽

Root Morphology ◽

Glutamate Synthase ◽

Cadmium Stress ◽

Magnetic Treatment ◽

Mineral Nutrient ◽

Cd Stress ◽

Nutrient Metabolism ◽

Nutrient Contents ◽

Populus Euramericana

Abstract Background: The potted experiment was carried out to investigate the mechanism of nutrient metabolism and seedling growth caused by magnetic treatment (MT) following exposure to cadmium (Cd) stress. One-year-old seedlings of Populus×euramericana 'Neva' were treated with different Cd(NO3)2 solutions for 30 days. Properties of seedling growth and root morphology were promoted by MT under Cd exposure.Results: Contents of ammonium (NH4+-N), nitrate (NO3--N), and total nitrogen (TN) in leaves, also NH4+-N and TN in roots, were increased by MT combined with Cd-stress, although NO3--N content was decreased. Activities of nitrate reductase (NR), nitrite reductase (NiR), glutathione reductase (GR), and glutamate synthase (GOGAT) in leaves and activities of NR, GS and GOGAT in roots were stimulated by MT; conversely, NiR activity in roots was inhibited. MT improved the synthesis of cysteine (Cys) and glutamine (Gln) in leaves and reduced the contents of glutamic acid (Glu) and glycine (Gly), while contents of Cys, Glu, Gln, and Gly were increased in roots. (4) The contents of Ca, Mg, Fe, Mn, Zn and Cu were increased by MT under Cd stress in leaves, whereas content of K was reduced. In roots, contents of K, Ca, and Fe were increased by MT under Cd-stress, but the contents of Na, Mg, Mn, Zn, and Cu were decreased.Conclusions: Magnetization could regulate the uptake of mineral nutrients by roots and translocation from the roots to aboveground parts by affecting the root morphology. MT could also improve nitrogen assimilation and the synthesis of free amino acids by stimulating the activities of key enzymes.

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Effect of Arbuscular Mycorrhiza and Temperature Control on Plant Growth, Yield, and Mineral Content of Tomato Plants Grown Hydroponically

HortScience ◽

10.21273/hortsci.48.12.1470 ◽

2013 ◽

Vol 48 (12) ◽

pp. 1470-1477 ◽

Cited By ~ 6

Author(s):

Martin Makgose Maboko ◽

Isa Bertling ◽

Christian Phillipus Du Plooy

Keyword(s):

Plant Growth ◽

Nutrient Uptake ◽

Temperature Control ◽

Mycorrhizal Fungi ◽

Nutrient Concentration ◽

Growth Yield ◽

Mineral Nutrient ◽

Nutrient Concentrations ◽

Mineral Concentration ◽

Temperature Controlled

Mycorrhizal inoculation improves nutrient uptake in a range of host plants. Insufficient nutrient uptake by plants grown hydroponically is of major environmental and economic concern. Tomato seedlings, therefore, were treated with a mycorrhizal inoculant (Mycoroot™) at transplanting to potentially enhance nutrient uptake by the plant. Then seedlings were transferred to either a temperature-controlled (TC) or a non-temperature-controlled (NTC) tunnel and maintained using the recommended (100%) or a reduced (75% and 50%) nutrient concentration. Plants grown in the NTC tunnel had significantly poorer plant growth, lower fruit mineral concentration, and lower yield compared with fruit from plants in the TC tunnel. Leaves from plants in the NTC tunnel had higher microelement concentrations than those in the TC tunnel. Highest yields were obtained from plants fertigated with 75% of the recommended nutrient concentration, and not from the 100% nutrient concentration. Application of arbuscular mycorrhizal fungi (AMF) neither enhanced plant growth, nor yield, nor fruit mineral nutrient concentrations. However, temperature control positively affected the fruit Mn and Zn concentration in the TC tunnel following AMF application.

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Salinity Influences Photosynthetic Characteristics, Water Relations, and Foliar Mineral Composition of Annona squamosa L.

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.2.243 ◽

1996 ◽

Vol 121 (2) ◽

pp. 243-248 ◽

Cited By ~ 12

Author(s):

Thomas E. Marler ◽

Yasmina Zozor

Keyword(s):

Gas Exchange ◽

Water Relations ◽

Salinity Stress ◽

Root Zone ◽

Dark Respiration ◽

Leaf Gas Exchange ◽

Chloride Concentration ◽

Sand Culture ◽

Mineral Nutrient ◽

Annona Squamosa

Leaf gas exchange, chlorophyll fluorescence, water relations, and mineral nutrient relations responses of Annona squamosa seedlings to mild salinity were studied in sand culture in five experiments during 1990, 1991, and 1993. Trees were irrigated with a complete nutrient solution (control) or with this solution amended to 3 or 6 dS·m-1 with sea salt. Inhibition of net CO2 assimilation, stomatal conductance of CO2, and transpiration was apparent within 2 weeks of initiating salinity treatments, and gas exchange continued to decline until day 30 to 35. The diurnal pattern of leaf gas exchange was not altered by increased salinity. Salinity reduced CO2, light energy, and water-use efficiencies. Salinity sometimes reduced the ratio of variable to maximum fluorescence below that of the control, and this response was highly dependent on the ambient light conditions that preceded the measurements. Dark respiration was unaffected by salinity stress. Root zone salinity of 3 dS·m-1 administered for 52 days did not influence foliar sodium concentration or the ratio of sodium to potassium, but increased chloride concentration and decreased nitrogen concentration. The sodium response indicated that some form of exclusion or compartmentation occurred. Salinity reduced osmotic potential of root tissue but did not influence foliar osmotic or predawn xylem potential. These results indicate that A. squamosa is sensitive to salinity stress, and that the responses to salinity are consistent with other salt-sensitive woody perennial species.

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Physiological and Nutritional Responses of ‘HB’ Pummelo [Citrus grandis (L.) Osbeck ‘Hirado Buntan’] to the Combined Effects of Low pH Levels and Boron Deficiency

HortScience ◽

10.21273/hortsci14708-19 ◽

2020 ◽

Vol 55 (4) ◽

pp. 449-456

Author(s):

Gaofeng Zhou ◽

Bixian Li ◽

Jianmei Chen ◽

Fengxian Yao ◽

Guan Guan ◽

...

Keyword(s):

Gas Exchange ◽

Southern China ◽

Leaf Gas Exchange ◽

Mineral Nutrients ◽

Low Ph ◽

Stress Factors ◽

Mineral Nutrient ◽

Nutrient Concentrations ◽

Boron Deficiency ◽

Combined Effects

Soil acidification and boron (B) starvation are two dominant abiotic stress factors impacting citrus production in the red soil region of southern China. To evaluate the combined effects of low pH and B deficiency on plant growth, gas exchange parameters, and the concentrations of B and other mineral nutrients, ‘HB’ pummelo seedlings were treated under B deficiency (0 μM H3BO3) or adequate B (23 μM H3BO3) conditions at various low pH levels (4.0, 5.0, and 6.0). The seedlings were grown with modified half-strength Hoagland’s solution under greenhouse conditions for 12 weeks. Plant biomass, leaf area, seedling height, and root traits were remarkably inhibited by low pH and B deficiency stresses, and these parameters were extremely reduced with the decrease in pH levels. After 12 weeks of treatment, typical stress symptoms associated with B deficiency in citrus leaf were observed, with more severe symptoms observed at pH 4.0 and 5.0 than at pH 6.0. Leaf gas exchange parameter measurements showed that leaf photosynthesis was significantly inhibited under both low pH and B-deficient conditions. Notably, the lower the pH level, the greater the inhibition under both normal and deficient B conditions. Further investigations of the mineral nutrient concentrations showed that under both low pH and B deficiency, the concentrations of B and other mineral nutrients were influenced remarkably, particularly at pH 4.0 and 5.0. The physiological and nutritional results of the ‘HB’ pummelo seedlings indicated that low pH can exacerbate the effects of B deficiency to a certain extent.

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Reexamining the empirical relation between plant growth and leaf photosynthesis

Functional Plant Biology ◽

10.1071/fp05310 ◽

2006 ◽

Vol 33 (5) ◽

pp. 421 ◽

Cited By ~ 63

Author(s):

Eric L. Kruger ◽

John C. Volin

Keyword(s):

Gas Exchange ◽

Plant Growth ◽

Leaf Area ◽

Leaf Gas Exchange ◽

Empirical Relation ◽

Leaf Photosynthesis ◽

Unit Leaf Area ◽

Leaf Mass ◽

Unit Leaf ◽

Growth Variation

Technological advances during the past several decades have greatly enhanced our ability to measure leaf photosynthesis virtually anywhere and under any condition. Associated with the resulting proliferation of gas-exchange data is a lingering uncertainty regarding the importance of such measurements when it comes to explaining intrinsic causes of plant growth variation. Accordingly, in this paper we rely on a compilation of data to address the following questions: from both statistical and mechanistic standpoints, how closely does plant growth correlate with measures of leaf photosynthesis? Moreover, in this context, does the importance of leaf photosynthesis as an explanatory variable differ among growth light environments? Across a wide array of species and environments, relative growth rate (RGR) was positively correlated with daily integrals of photosynthesis expressed per unit leaf area (Aarea), leaf mass (Amass), and plant mass (Aplant). The amount of RGR variation explained by these relationships increased from 36% for the former to 93% for the latter. Notably, there was close agreement between observed RGR and that estimated from Aplant after adjustment for theoretical costs of tissue construction. Overall, based on an analysis of growth response coefficients (GRCs), gross assimilation rate (GAR), a photosynthesis-based estimate of biomass gain per unit leaf area, explained about as much growth variation as did leaf mass ratio (LMR) and specific leaf area (SLA). Further analysis of GRCs indicated that the importance of GAR in explaining growth variation increased with increasing light intensity. Clearly, when considered in combination with other key determinants, appropriate measures of leaf gas exchange effectively capture the fundamental role of leaf photosynthesis in plant growth variation.

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Exogenous Carbon Magnifies Mycorrhizal Effects on Growth Behaviour and Sucrose Metabolism in Trifoliate Orange

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha46210987 ◽

2018 ◽

Vol 46 (2) ◽

pp. 365-370 ◽

Cited By ~ 1

Author(s):

Li TIAN ◽

Yan LI ◽

Qiang-Sheng WU

Keyword(s):

Plant Growth ◽

Root Morphology ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Arbuscular Mycorrhizas ◽

Sucrose Metabolism ◽

Poncirus Trifoliata ◽

Trifoliate Orange ◽

Positive Effects ◽

Mycorrhizal Plants

Arbuscular mycorrhizas (AMs) need the carbohydrates from host plants for its growth, whereas it is not clear whether exogenous carbon affects mycorrhizal roles. A two-chambered rootbox was divided into root + hyphae chamber and hyphae chamber (free of roots) by 37-μm nylon mesh, in which trifoliate orange (Poncirus trifoliata) seedlings and Funneliformis mosseae were applied into root + hyphae chamber, and exogenous 40 mmol/L fructose, glucose and sucrose was applied to hyphae chamber. Application of exogenous sugars dramatically elevated root mycorrhizal colonization. Sole arbuscular mycorrhizal fungi (AMF) inoculation significantly promoted plant growth and root morphology than non-AMF treatment. Mycorrhiza-improved plant growth and root modification could be enlarged by exogenous carbon, especially fructose. Exogenous carbon markedly increased root fructose, glucose and sucrose accumulation in mycorrhizal plants, especially sucrose. Exogenous fructose significantly reduced leaf and root sucrose synthase (SS) activity in synthesis direction and increased them in cleavage direction in AMF seedlings. Exogenous glucose and sucrose heavily elevated root SS activity of mycorrhizal seedlings in synthesis and cleavage direction and reduced leaf SS activity in synthesis direction. Leaf acid invertase (AI) and neutral invertase (NI) activities of mycorrhizal seedlings were decreased by exogenous carbon, except sucrose in NI. Exogenous fructose significantly increased root AI and NI activity in mycorrhizal plants. These results implied that mycorrhizal inoculation represented positive effects on plant growth, root morphology, and sucrose metabolism of trifoliate orange, which could be magnified further by exogenous carbon, especially fructose.

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Mycorrhizal Fungi Enhance Yield and Berry Chemical Composition of in Field Grown “Cabernet Sauvignon” Grapevines (V. vinifera L.)

Agriculture ◽

10.3390/agriculture11070615 ◽

2021 ◽

Vol 11 (7) ◽

pp. 615

Author(s):

Marko Karoglan ◽

Tomislav Radić ◽

Marina Anić ◽

Željko Andabaka ◽

Domagoj Stupić ◽

...

Keyword(s):

Gas Exchange ◽

Mycorrhizal Fungi ◽

Leaf Gas Exchange ◽

Grape Berry ◽

Vitis Vinifera L ◽

Cabernet Sauvignon ◽

Gas Exchange Parameters ◽

Wine Production ◽

Yield Parameters ◽

Total Anthocyanins

The aim of this study was to assess the influence of the application of mycorrhizal fungal inoculum on “Cabernet Sauvignon” (Vitis vinifera L.) leaf gas exchange, yield parameters, as well as grape berry composition, especially regarding phenolic compounds. The experiment was conducted over two years under natural vineyard conditions of the Zagreb wine-growing area, the continental region of Croatia. “Cabernet Sauvignon” grapevines were grafted on SO4 rootstock, both being commonly used in all wine production areas in Croatia. Results obtained demonstrated that symbiotic grapevines, in general, expressed improved leaf gas exchange parameters and higher yield parameters, especially regarding the number of clusters per vine. It should be emphasized that mycorrhizal fungi affected higher total flavan-3-ols, total anthocyanins, and total polyphenols in berry skin in both experimental years. Despite variation in some yield parameters, generally, it is possible to obtain higher yields together with the improved phenolic composition of grapes.

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Petunia Performance Under Application of Animal-Based Protein Hydrolysates: Effects on Visual Quality, Biomass, Nutrient Content, Root Morphology, and Gas Exchange

Frontiers in Plant Science ◽

10.3389/fpls.2021.640608 ◽

2021 ◽

Vol 12 ◽

Author(s):

Giuseppe Cristiano ◽

Barbara De Lucia

Keyword(s):

Gas Exchange ◽

Interaction Effect ◽

Root Morphology ◽

Leaf Gas Exchange ◽

Foliar Spray ◽

Visual Quality ◽

Plant Production ◽

Root Surface Area ◽

High Dose ◽

Dose Method

Sustainable plant production practices have been implemented to reduce the use of synthetic fertilizers and other agrochemicals. One way to reduce fertilizer use without negatively impacting plant nutrition is to enhance crop uptake of nutrients with biostimulants. As the effectiveness of a biostimulant can depend on the origin, species, dose, and application method, the aim of this research was to evaluate the effect of a commercial animal-based protein hydrolysate (PH) biostimulant on the visual quality, biomass, macronutrient content, root morphology, and leaf gas exchange of a petunia (Petunia × hybrida Hort. “red”) under preharvest conditions. Two treatments were compared: (a) three doses of an animal-based PH biostimulant: 0 (D0 = control), 0.1 (D0.1 = normal), and 0.2 g L–1 (D0.2 = high); (b) two biostimulant application methods: foliar spray and root drenching. The dose × method interaction effect of PH biostimulant on the plants was significant in terms of quality grade and fresh and dry biomass. The high dose applied as foliar spray produced petunias with extra-grade visual quality (number of flowers per plant 161, number of leaves per plant 450, and leaf area per plant 1,487 cm2) and a total aboveground dry weight of 35 g, shoots (+91%), flowers (+230%), and leaf fresh weight (+71%). P and K contents were higher than in untreated petunias, when plants were grown with D0.2 and foliar spray. With foliar spray at the two doses, SPAD showed a linear increase (+21.6 and +41.0%) with respect to untreated plants. The dose × method interaction effect of biostimulant application was significant for root length, projected and total root surface area, and number of root tips, forks, and crossings. Concerning leaf gas exchange parameters, applying the biostimulant at both doses as foliar spray resulted in a significant improvement in net photosynthesis (D0.1: 22.9 μmol CO2 m–2 s–1 and D0.2: 22.4 μmol CO2 m–2 s–1) and stomatal conductance (D0.1: 0.42 mmol H2O m–2 s–1 and D0.2: 0.39 mmol H2O m–2 s–1) compared to control. These results indicate that application of PH biostimulant at 0.2 g L–1 as foliar spray helped to achieve extra-grade plants and that this practice can be exploited in sustainable greenhouse conditions for commercial production of petunia.

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