VESICULAR-ARBUSCULAR MYCORRHIZAL (VAM) FUNGI ALTER ROOT GROWTH OF PROSOPIS ALBA (CHILEAN MESQUITE) IN CONTAINERS

Effects of VAM fungal inoculum, Glomus intraradices Schenk & Smith, on the growth of Chilean mesquite in containers were investigated as part of a nursery container system for production of xeric trees. Seedling liners of Chilean mesquite were transplanted into 27-liter containers filled with a 3 pine bark : 1 peat moss : 1 sand medium. Before transplanting, 50% of the trees were band-inoculated at a depth of 8 to 12 cm below the growth medium surface with 35 g per container of Glomus intradices (Nutrilink, NPI, Salt Lake City, UT), approximately 1,000 spores g-1. All trees were top-dressed with 15 g Osmocote 18N-2.6P-9.9K (Grace-Sierra, Milpitas, CA) and 3 g Micromax (Grace-Sierra, Milpitas, CA) fertilizers and grown in a fiberglass greenhouse under 50% light exclusion. After 4 months, all inoculated tree root systems were colonized, and the percent infection was 47%. Noninoculated trees remained nonmycorrhizal. There were no differences in height, total shoot length, shoot dry weight, or root dry weight between inoculated and non-inoculated trees; however, total root length and specific root length of inoculated trees were less than those of noninoculated trees. These results suggest that the VAM fungi altered the root architecture of inoculated trees such that root systems of these trees had thicker roots with fewer fine roots elongating into the growth medium profile.

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Screening of Soybean Genotypes Based on Root Morphology and Shoot Traits Using the Semi-Hydroponic Phenotyping Platform and Rhizobox Technique

Agronomy ◽

10.3390/agronomy12010056 ◽

2021 ◽

Vol 12 (1) ◽

pp. 56

Author(s):

Mohammad Salim ◽

Yinglong Chen ◽

Heng Ye ◽

Henry T. Nguyen ◽

Zakaria M. Solaiman ◽

...

Keyword(s):

Root System ◽

System Architecture ◽

Root Length ◽

Specific Root Length ◽

Root Traits ◽

Dry Weight ◽

Root Systems ◽

Root System Architecture ◽

Flowering Stage ◽

Soybean Genotypes

Root-system architecture is vital for improving soybean (Glycine max L.) growth and nutrient uptake. We characterised root-system architecture and shoot traits of 30 soybean genotypes in a semi-hydroponic system 35 days after sowing (DAS) and validated eight genotypes with contrasting root-system architecture in 1.5 m-deep rhizoboxes at the flowering stage. Among them, two genotypes were selected for evaluation through to maturity. Abundant variation (coefficient of variation values ≥ 0.25) was observed in 11 of 13 measured roots and shoot traits during the early growth stage. After late growth stages, strong positive correlations were found between root traits and shoot traits, except for specific root length and diameter. Seed yield and yield traits at final harvest significantly differed between two contrasting soybean genotypes. The large-rooted genotype had a higher harvest index than the small-rooted genotype. Soybean genotypes with larger root systems had a long time to flowering than those with smaller root systems. Genotypes with large-root systems had 106% more leaf area, and 245% more shoot dry weight than those with small systems, presumably due to high canopy photosynthesis to supply the demand for carbon assimilates to roots. Total root length, and root: shoot ratio-traits data collected in the rhizobox study, strongly correlated with the same traits in the semi-hydroponic phenotyping system. We found genetic variation and phenotypic plasticity in other root and shoot traits such as taproot depth, root dry weight, specific root length, and average root diameter among the tested genotypes. Phenology, particularly time to flowering, was associated with root system size. Some root and shoot traits in the semi-hydroponic phenotyping system at the seedling stage produced similar rankings at the later phenological (flowering) stage when grown in the soil-filled rhizoboxes. The soybean genotypes characterised by vastly different root traits could be used for further glasshouse and field studies to improve adaptation to drought and other specific environments.

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Response of Taxus times media var. densiformis to inoculation with arbuscular mycorrhizal fungi

Canadian Journal of Forest Research ◽

10.1139/x97-182 ◽

1998 ◽

Vol 28 (1) ◽

pp. 150-153

Author(s):

J N Gemma ◽

R E Koske ◽

E M Roberts ◽

S Hester

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Glomus Intraradices ◽

Arbuscular Mycorrhizal ◽

Dry Weight ◽

Root Systems ◽

Stem Diameter ◽

Rooted Cuttings ◽

Shoot Dry Weight ◽

Mycorrhizal Plants

Rooted cuttings of Taxus times media var. densiformis Rehd. were inoculated with the arbuscular mycorrhizal fungi Gigaspora gigantea (Nicol. & Gerd.) Gerd. & Trappe or Glomus intraradices Schenck and Smith and grown for 9-15 months in a greenhouse. At the completion of the experiments, leaves of inoculated plants contained significantly more chlorophyll (1.3-4.1 times as much) than did noninoculated plants. In addition, mycorrhizal plants had root systems that were significantly larger (1.3-1.4 times) and longer (1.7-2.1 times) than nonmycorrhizal plants, and they possessed significantly more branch roots (1.3-2.9 times). No differences in stem diameter and height or shoot dry weight were evident at the end of the experiments, although the number of buds was significantly greater in the cuttings inoculated with G. intraradices after 15 months.

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Comparison of Root System Morphology of Cucurbit Rootstocks for Use in Watermelon Grafting

HortTechnology ◽

10.21273/horttech04098-18 ◽

2018 ◽

Vol 28 (5) ◽

pp. 629-636 ◽

Cited By ~ 4

Author(s):

Matthew B. Bertucci ◽

David H. Suchoff ◽

Katherine M. Jennings ◽

David W. Monks ◽

Christopher C. Gunter ◽

...

Keyword(s):

Root System ◽

Surface Area ◽

Root Length ◽

Dry Weight ◽

Root Systems ◽

Root Surface ◽

Root Diameter ◽

Root Surface Area ◽

Diameter Class ◽

Main Effect

Grafting of watermelon (Citrullus lanatus) is an established production practice that provides resistance to soilborne diseases or tolerance to abiotic stresses. Watermelon may be grafted on several cucurbit species (interspecific grafting); however, little research exists to describe root systems of these diverse rootstocks. A greenhouse study was conducted to compare root system morphology of nine commercially available cucurbit rootstocks, representing four species: pumpkin (Cucurbita maxima), squash (Cucurbita pepo), bottle gourd (Lagenaria siceraria), and an interspecific hybrid squash (C. maxima × C. moschata). Rootstocks were grafted with a triploid watermelon scion (‘Exclamation’), and root systems were compared with nongrafted (NG) and self-grafted (SG) ‘Exclamation’. Plants were harvested destructively at 1, 2, and 3 weeks after transplant (WAT), and data were collected on scion dry weight, total root length (TRL), average root diameter, root surface area, root:shoot dry-weight ratio, root diameter class proportions, and specific root length. For all response variables, the main effect of rootstock and rootstock species was significant (P < 0.05). The main effect of harvest was significant (P < 0.05) for all response variables, with the exception of TRL proportion in diameter class 2. ‘Ferro’ rootstock produced the largest TRL and root surface area, with observed values 122% and 120% greater than the smallest root system (‘Exclamation’ SG), respectively. Among rootstock species, pumpkin produced the largest TRL and root surface area, with observed values 100% and 82% greater than those of watermelon, respectively. These results demonstrate that substantial differences exist during the initial 3 WAT in root system morphology of rootstocks and rootstock species available for watermelon grafting and that morphologic differences of root systems can be characterized using image analysis.

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Novel approaches to improving growth of pasture legumes at low phosphorus levels

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2014.76.2952 ◽

2014 ◽

Vol 76 ◽

pp. 197-202

Author(s):

S.N. Nichols ◽

J.R. Crush

Keyword(s):

White Clover ◽

Root Length ◽

Specific Root Length ◽

Root Traits ◽

Dry Weight ◽

Root Weight ◽

Soil P ◽

P Acquisition ◽

Shoot Dry Weight ◽

Use Efficiency

Abstract Strategies to reduce the economic and environmental costs of phosphate (P) fertiliser use in mixed pastures through plant breeding are focussed on inefficiencies in the legume component. One approach is breeding within white clover for root systems with improved P acquisition properties. Selection for root length per unit root weight (specific root length, SRL) showed that higher SRL plants could retain more biomass in the above ground fraction with decreasing soil P, whereas plants with lower SRL diverted more biomass to roots. Back cross 1 (BC1) generation interspecific hybrids between white clover and a wild relative, Trifolium uniflorum L., may possess additional root traits influencing P acquisition. In glasshouse experiments, some T. repens × T. uniflorum hybrids, back-crossed to white clover, also exhibited higher shoot dry weight than their white clover cultivar parents at low nutrient supply levels and low to intermediate soil Olsen P. This, combined with low internal P concentrations, suggests some BC1 hybrids may be more tolerant of low soil P than white clover. Differences in both P acquisition ability and internal P use efficiency may contribute to the observed yield differences. There are good prospects for delivery of new-generation clover cultivars with improved phosphate use efficiency to New Zealand farmers. Keywords: phosphorus, white clover, Trifolium uniflorum, interspecific

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Vesicular-arbuscular Mycorrhizal Peat-based Substrates Enhance Symbiosis Establishment and Growth of Three Micropropagated Species

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.118.6.896 ◽

1993 ◽

Vol 118 (6) ◽

pp. 896-901 ◽

Cited By ~ 27

Author(s):

H. Wang ◽

S. Parent ◽

A. Gosselin ◽

Y. Desjardins

Keyword(s):

Glomus Intraradices ◽

Arbuscular Mycorrhizal ◽

Dry Weight ◽

Gerbera Jamesonii ◽

Subsequent Growth ◽

Vam Fungi ◽

Vesicular Arbuscular ◽

Ornamental Species ◽

Term Benefit

Micropropagated plantlets of Gerbera jamesonii H. Bolus ex Hook. F. `Terra Mix', Nephrolepis exaltata (L.) Schott `Florida Ruffles', and Syngonium podophyllum Schott `White Butterfly' were inoculated with two vesicular-arbuscular mycorrhizal (VAM) fungi, Glomus intraradices Schenck and Smith and G. vesiculiferum Gerderman and Trappe. They were potted in three peat-based media to determine the effects of mycorrhizal peat substrate on acclimatization and subsequent growth of micropropagated plantlets under greenhouse conditions. Symbiosis was established between the three ornamental species and VAM fungi within 4 to 8 weeks of culture in the greenhouse, but not during acclimatization. Mortality of Gerbera and Nephrolepis mycorrhizal plantlets was reduced at week 8 compared to the noninoculated control. A peat-based substrate low in P and with good aeration improved VAM fungi spread and efficiency. Mycorrhizal substrates had a long-term benefit of increasing leaf and root dry weight of Gerbera and Nephrolepis. Mycorrhizal Gerbera plants flowered significantly faster than non-mycorrhizal plants.

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Growth and physiological responses of the citrus rootstock Swingle citrumelo seedlings to partial rootzone drying and deficit irrigation

The Journal of Agricultural Science ◽

10.1017/s0021859610000377 ◽

2010 ◽

Vol 148 (5) ◽

pp. 593-602 ◽

Cited By ~ 23

Author(s):

J. C. MELGAR ◽

J. M. DUNLOP ◽

J. P. SYVERTSEN

Keyword(s):

Root Length ◽

Deficit Irrigation ◽

Root Zone ◽

Specific Root Length ◽

Total Content ◽

Dry Weight ◽

Citrus Rootstock ◽

Irrigation Treatments ◽

Partial Rootzone Drying ◽

Swingle Citrumelo

SUMMARYThe effects of deficit irrigation (DI) and partial rootzone drying (PRD) on the growth and mineral nutrition of citrus rootstock seedlings in the glasshouse were determined, as well as the potential of DI and PRD to trigger root-to-shoot signalling of abscisic acid (ABA) to increase the growth per amount of water used (water use efficiency (WUE)). In the DI study, 3-month-old seedlings of the important citrus rootstock Swingle citrumelo with intact roots received three irrigation treatments: control (1·00 evapotranspiration (ET)), 0·75 ET and 0·50 ET. DI clearly decreased growth, the net assimilation of CO2 (ACO2), WUE and the total content of N and K in leaves, even though concentrations of leaf N and K were increased in the drought-stressed smaller plants. Root K was not affected by DI treatments. Leaf ABA concentration increased linearly with DI. For the PRD study, root systems of 6-month-old Swingle citrumelo were split into half and allowed to become established in adjacent pots. There were three irrigation treatments: control (1·00 of the total crop ET, 0·50 in each pot), PRD 50-0 (0·50 ET by weight applied to only one-half of root zone) and DI 25-25 (0·50 ET in total, with 0·25 ET applied to each root half). Although the total root length was decreased by the DI 25-25 treatment, PRD 50-0 did not affect any growth characteristics compared to control plants. The dry root zone of the PRD 50-0 treatment had a higher specific root length, longer roots per dry weight, than the wet root zone. Leaf ACO2 and WUE of the DI 25-25 treatment were significantly lower than control plants after 11 weeks. Although the total contents of N and K in leaves were not affected by either PRD treatment, the concentrations of N and K in leaves were increased by DI 25-25. Root K was decreased by PRD treatments. Leaf ABA concentration was increased by PRD 50-0 but not by DI 25-25. Although all drought stress treatments increased the levels of ABA in leaves, DI and PRD treatments did not affect the whole plant WUE. Compared to well-irrigated control plants, DI reduced growth, whereas PRD 50-0 did not.

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Ameliorative effect of Ascorbic acid and biochar on Growth, and antioxidant enzymes on early Seedling of Sorghum under Salinity Conditions

10.21203/rs.3.rs-136040/v1 ◽

2021 ◽

Author(s):

Aboagla Elsiddig ◽

Guisheng Zhou ◽

Nimir Ahmed

Keyword(s):

Ascorbic Acid ◽

Antioxidant Enzymes ◽

Root Length ◽

Specific Root Length ◽

Dry Weight ◽

Controlled Study ◽

Emergence Rate ◽

Sorghum Seedling ◽

Physiological Attributes ◽

Total Dry Weight

Abstract Salt stress is one of the major environmental stresses that limits the growth, antioxidant defense and sustainable crop productivity. A controlled study was done to determine the ameliorative effects of ascorbic acid (ASA) (0, 568, and 850 μM) and biochar (BC) (0, 2 and 4% BC [w/w]) on emergence, growth, and physiological attributes of sorghum grown under three salinity levels (0, 100, and 200 mM NaCl). High salinity stress significantly reduced emergence percentage, emergence rate, shoot length, root length, specific root length, total fresh weight (T.F.W), total dry weight (T.D.W), the activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), but increased malondialdehyde (MDA) content. At the 200 mM NaCl level, 850 μM ASA with 4% BC enhanced most of the physiological attributes determined. At the 200 mM salinity level, total dry weight of sorghum seedling was increased by 42.7% and 23.1% at 2% and 4% BC levels, respectively as compared with non-BC control. The highest emergence rate at 200 mM NaCl was achieved at 4% BC and 850 μM ASA level. Our study suggested that the combined application of ASA and BC at appropriate amount and concentration on sorghum seedling may be helpful in salt tolerance and getting increase antioxidant enzymes that mitigate harms affected by saline problems worldwide.

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In situ Root Phenotypes of Cotton Seedlings Under Phosphorus Stress Revealed Through RhizoPot

Frontiers in Plant Science ◽

10.3389/fpls.2021.716691 ◽

2021 ◽

Vol 12 ◽

Author(s):

Zichen Zhang ◽

Lingxiao Zhu ◽

Dongxiao Li ◽

Nan Wang ◽

Hongchun Sun ◽

...

Keyword(s):

Growth Rate ◽

Root Length ◽

Root Length Density ◽

Root Hairs ◽

Specific Root Length ◽

Dry Weight ◽

P Deficiency ◽

Branch Density ◽

P Absorption

Phosphorus (P) deficiency is a common challenge in crop production because of its poor mobility through the soil. The root system plays a significant role in P absorption from the soil and is the initial indicator of low P levels. However, the phenotypic dynamics and longevity of cotton roots under P stress remain unknown. In this study, RhizoPot, an improvised in situ root observation device, was used to monitor the dynamics of root phenotypes of cotton seedlings under P-deficient (PD) and P-replete (PR) conditions. Low P stress reduced P absorption and accumulation in the roots, leading to low dry weight accumulation. Cotton seedlings responded to low P stress by increasing the number of lateral roots, specific root length, branch density, root length density, and length of root hairs. Additionally, the life span of root hairs was prolonged. Low P stress also reduced the average diameter of roots, promoted root extension, expanded the root coverage area, and increased the range of P acquisition. Principal component analysis revealed that the net root growth rate, root length density, root dry weight, P absorption efficiency, average root hair length, and taproot daily growth significantly influenced the cotton root architecture. Collectively, these results show that low P stress reduces the net growth rate of cotton seedling roots and restricts plant growth. Plants respond to P deficiency by extending the life span of root hairs and increasing specific root length and lateral root branch density. This change in root system architecture improves the adaptability of plants to low P conditions. The findings of this study may guide the selection of cotton varieties with efficient P utilization.

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Effect of Penicillium bilaii inoculation and phosphorus fertilisation on root and shoot parameters of field-grown pea

Canadian Journal of Plant Science ◽

10.4141/p00-083 ◽

2001 ◽

Vol 81 (3) ◽

pp. 361-366 ◽

Cited By ~ 29

Author(s):

J. Kevin Vessey ◽

Krista G Heisinger

Keyword(s):

Pisum Sativum ◽

Root Morphology ◽

Root Length ◽

Specific Root Length ◽

Dry Weight ◽

Western Canada ◽

Microbial Inoculants ◽

P Nutrition ◽

P Content ◽

Phosphorus Fertilisation

The mechanisms underlying the stimulating effect of Penicillium bilaii inoculation on the growth of crop plants are not clear. The effect of P. bilaii inoculation on root morphology [dry weight (DW), length and specific root length) and other root and shoot parameters of pea were investigated at two field sites in western Canada in 1996. Pea (Pisum sativum L.) was grown at three levels of P fertilization (0, 6.4 and 19.3 kg ha–1) at Ellerslie, AB, and Outlook, SK. Shoot dry matter, P concentrations, P content and nodulation were also measured in pea plants harvested at the seven- to nine-node stage. Soil cores were used to sample roots. Although plants were responsive to P fertiliser at both sites, P. bilaii inoculation affected pea growth at the Ellerslie site only. At this site, P. bilaii inoculation increased root length by 48%, specific root length (m g–1 root DW) by 21%, root DW by 13%, and shoot P concentration by 13% in treatments that received no P fertiliser. We suggest that the stimulating effect of P. bilaii inoculation on crop P nutrition is partly explained by increases in root absorptive capacity in the presence of the fungus. However, this effect was only significant under P-limited conditions. Key words: Microbial inoculants, Pisum sativum, Penicillium bilaii, phosphorus, root length, root morphology

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Differences in Seedling Growth of 23 Creeping Bentgrass Cultivars under Polyethylene Glycol-induced Drought Conditions

HortTechnology ◽

10.21273/horttech03990-18 ◽

2018 ◽

Vol 28 (3) ◽

pp. 327-331 ◽

Cited By ~ 3

Author(s):

Qi Zhang ◽

Liqi Yang ◽

Kevin Rue

Keyword(s):

Polyethylene Glycol ◽

Seedling Growth ◽

Root Length ◽

Crop Production ◽

Weight Ratio ◽

Specific Root Length ◽

Creeping Bentgrass ◽

Dry Weight ◽

Shoot Dry Weight ◽

Stress Damage

Drought is the most important abiotic stress in crop production including turfgrass management. Using drought tolerant plants can help minimize stress damage. In this study, 23 commercially available cultivars of creeping bentgrass (Agrostis stolonifera) were evaluated for their responses to drought stress that was induced by polyethylene glycol (PEG) 6000 in a hydroponic system during the seed germination and seedling growth stage. In such a system, water potential was adjusted to 0.0 (the control), −0.3, and −0.6 MPa to mimic the drought condition. The absolute water content (AWC), shoot dry weight (SDW), root dry weight (RDW), longest root length (LRL), specific root length (SRL), and root-to-shoot dry weight ratio (RSR) in the plants grown for 4 weeks in the treatment were determined. Results showed that SDW and LRL were unaffected by drought; however, RDW and RSR increased, whereas SRL and AWC were reduced under drought. Among the 23 creeping bentgrass cultivars evaluated, Independence and Crystal Bluelinks had a higher turfgrass performance index (TPI), which represented the number of times a cultivar ranked in the top statistical group across all parameters. The results suggest that ‘Independence’ and ‘Crystal Bluelinks’ may be more adapted to drought than the other cultivars at the seedling stage.

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