Chlorophyll Fluorescence, Photosynthesis and Growth of Tomato Plants as Affected by Long-Term Oxygen Root Zone Deprivation and Grafting

A greenhouse experiment was conducted to study the effects of the O2 root zone level and grafting on chlorophyll fluorescence, photosynthesis and growth of cherry tomato grown in a hydroponic system. Two O2 concentrations in the root zone, namely Ox (saturation level) and Ox- (2–3 mg L−1), were applied for 30 days on self-grafted cherry tomato Dreamer or grafted onto the hybrids Arnold, Beaufort, Maxifort and Top Pittam. Root hypoxia increased minimum fluorescence (by 10%) while it decreased variable fluorescence and the maximum quantum yield of PSII (up to 16 and 8%, respectively). Moreover, it reduced leaf photosynthesis, transpiration and stomatal conductance (by 12, 17 and 13%, respectively), whereas it increased leaf electrolyte leakage (by 2.1%). The graft combinations showed a different ability in buffering the effects of root hypoxia on plant growth and related components, and these differences were related to their root biomass. The minimum fluorescence was negatively correlated to plant growth, so it may be a useful indicator to select tolerant rootstocks to root hypoxia. Our results suggest the occurrence of both diffusive and metabolic constraints to tomato photosynthesis under root hypoxia, a condition that can be mitigated by selecting rootstocks with a more developed root system.

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Comparison of Cabbage Seedling Growth in Four Transplant Production Systems

HortTechnology ◽

10.21273/horttech.9.1.133a ◽

1999 ◽

Vol 9 (1) ◽

pp. 133a

Author(s):

Jonathan M. Frantz ◽

Gregory E. Welbaum ◽

Zhengxing Shen ◽

Ron Morse

Keyword(s):

Plant Growth ◽

Leaf Area ◽

Water Availability ◽

Production Systems ◽

Root Zone ◽

Control Plant ◽

Seedling Mortality ◽

Hydroponic System ◽

Black Plastic ◽

And Control

“Float-bed” (FB) is a simple hydroponic system used by the tobacco industry for transplant production. “Ebb-and-flood” (EF) is a modified FB system with periodic draining of the bed to limit water availability and control plant growth. Field-bed cabbage (Brassica oleracea L. gp. Capitata) transplant production was compared with FB, EF, and overhead-irrigated plug-tray greenhouse systems. Plants were produced in May and June and transplanted in a field near Blacksburg, Va., in June and July of 1994 and 1995, respectively. Beds for FB and EF production consisted of galvanized metal troughs (3.3 × 0.8 × 0.3 m) lined with a double layer of 0.075-mm-thick black plastic film. In 1994, both EF and FB seedlings were not hardened before transplanting, were severely stressed after transplanting, and had higher seedling mortality compared with plants from other systems. Plug-tray transplants showed the greatest increase in leaf area following transplanting and matured earlier than seedlings produced in other systems. In 1995, EF- and FB-grown cabbage plants were hardened by withholding water before transplanting, and seedlings had greater fresh mass and leaf area than plug-tray or field-bed seedlings 3.5 weeks after transplanting. Less succulent cabbage transplants were grown in EF and FB systems containing 66 mg·L-1 N (40% by nitrate) and 83 mg·L-1 K. Compared with the FB system, the EF system allowed control of water availability, which slowed plant growth, and increased oxygen concentration in the root zone. Both EF and FB systems are suitable for cabbage transplant production.

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Root-associated microbiomes of wheat under the combined effect of plant development and nitrogen fertilization

Microbiome ◽

10.1186/s40168-019-0750-2 ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 25

Author(s):

Shuaimin Chen ◽

Tatoba R. Waghmode ◽

Ruibo Sun ◽

Eiko E. Kuramae ◽

Chunsheng Hu ◽

...

Keyword(s):

Community Structure ◽

Plant Growth ◽

Microbial Communities ◽

Root Zone ◽

N Fertilization ◽

Plant Roots ◽

Growth Stages ◽

Ripening Stages ◽

N Input

Abstract Background Plant roots assemble microbial communities both inside the roots and in the rhizosphere, and these root-associated microbiomes play pivotal roles in plant nutrition and productivity. Although it is known that increased synthetic fertilizer input in Chinese farmlands over the past 50 years has resulted in not only increased yields but also environmental problems, we lack a comprehensive understanding of how crops under elevated nutrient input shape root-associated microbial communities, especially through adjusting the quantities and compositions of root metabolites and exudates. Methods The compositions of bacterial and fungal communities from the roots and rhizosphere of wheat (Triticum aestivum L.) under four levels of long-term inorganic nitrogen (N) fertilization were characterized at the tillering, jointing and ripening stages. The root-released organic carbon (ROC), organic acids in the root exudates and soil organic carbon (SOC) and soil active carbon (SAC) in the rhizosphere were quantified. Results ROC levels varied dramatically across wheat growth stages and correlated more with the bacterial community than with the fungal community. Rhizosphere SOC and SAC levels were elevated by long-term N fertilization but varied only slightly across growth stages. Variation in the microbial community structure across plant growth stages showed a decreasing trend with N fertilization level in the rhizosphere. In addition, more bacterial and fungal genera were significantly correlated in the jointing and ripening stages than in the tillering stage in the root samples. A number of bacterial genera that shifted in response to N fertilization, including Arthrobacter, Bacillus and Devosia, correlated significantly with acetic acid, oxalic acid, succinic acid and tartaric acid levels. Conclusions Our results indicate that both plant growth status and N input drive changes in the microbial community structure in the root zone of wheat. Plant growth stage demostrated a stronger influence on bacterial than on fungal community composition. A number of bacterial genera that have been described as plant growth-promoting rhizobacteria (PGPR) responded positively to N fertilization, and their abundance correlated significantly with the organic acid level, suggesting that the secretion of organic acids may be a strategy developed by plants to recruit beneficial microbes in the root zone to cope with high N input. These results provide novel insight into the associations among increased N input, altered carbon availability, and shifts in microbial communities in the plant roots and rhizosphere of intensive agricultural ecosystems.

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Physiology and production of cherry tomato cultivars in a hydroponic system using brackish water

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v25n4p219-227 ◽

2021 ◽

Vol 25 (4) ◽

pp. 219-227

Author(s):

Mateus C. Batista ◽

Ronaldo do Nascimento ◽

Sebastião de O. Maia Júnior ◽

Elka C. S. Nascimento ◽

Carlos V. de C. Bezerra ◽

...

Keyword(s):

Electrical Conductivity ◽

Nutrient Solution ◽

Brackish Water ◽

Arid Regions ◽

Cherry Tomato ◽

Tomato Plants ◽

Hydroponic System ◽

Photosynthetic System ◽

Salinity Levels ◽

Tomato Cultivars

ABSTRACT Agricultural production has become a challenge in arid and semi-arid regions due to the scarcity of water for irrigation, so brackish water is commonly used. The present study aimed to evaluate the physiological and production responses of cherry tomato cultivars under salinity levels of the nutrient solution in a hydroponic system. The experiment was conducted in a split plot and 5 × 3 factorial scheme with four repetitions. The factors corresponded to different values of electrical conductivity of the nutrient solution (ECns 2.5, 4.0, 5.5, 7.0 and 8.5 dS m-1) and cultivars (Samambaia, Tomate Vermelho and Caroline). The increase in nutrient solution salinity negatively affected the gas exchange, electrolyte leakage and photosynthetic pigments of the cherry tomato cultivars, mainly with the prolongation of stress. The photosynthetic system was efficient up to 4.0 dS m-1, but, above this electrical conductivity in the nutrient solution, there was photoinhibition or photodamage in the cherry tomato plants at 30 days after transplanting. The cherry tomato cultivars Samambaia and Caroline were the most adapted to brackish solutions, while Tomate Vermelho was the most susceptible.

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Tomato plant growth as affected by horizontally unequal osmotic concentrations in rock-wool.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v29i3.17005 ◽

1981 ◽

Vol 29 (3) ◽

pp. 189-197

Author(s):

A. Cerda ◽

J.P.N.L.R. van Eysinga

Keyword(s):

Electrical Conductivity ◽

Plant Growth ◽

Root Zone ◽

Nutrient Concentrations ◽

Osmotic Concentration ◽

Tomato Plants ◽

Split Root ◽

Split Root System ◽

The Mean ◽

Rock Wool

Tomato plants, cv. Moneydor, were grown in rockwool in a split-root system with equal or different osmotic concentrations. Fruit yield was negatively correlated with the mean electrical conductivity (EC) of both parts of the system. In treatments with two different EC values in the root zone, root development was better in the part with the low EC, and water uptake was higher. Nutrient concentrations showed an increase in the part with the low EC when differences in EC between both parts were 4 mS/cm [4 mmho/cm] or more. A possible explanation is that solutes move through the roots from the part with high to the part with the low osmotic concentration. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Plant growth-promoting endophytic bacteria versus pathogenic infections: an example ofBacillus amyloliquefaciensRWL-1 andFusarium oxysporumf. sp.lycopersiciin tomato

PeerJ ◽

10.7717/peerj.3107 ◽

2017 ◽

Vol 5 ◽

pp. e3107 ◽

Cited By ~ 31

Author(s):

Raheem Shahzad ◽

Abdul Latif Khan ◽

Saqib Bilal ◽

Sajjad Asaf ◽

In-Jung Lee

Keyword(s):

Plant Growth ◽

Bacillus Amyloliquefaciens ◽

Root Zone ◽

Disease Incidence ◽

Lower Amount ◽

Bacterial Endophytes ◽

Tomato Plants ◽

Plant Growth Promoting ◽

Growth Promoting

Fungal pathogenic attacks are one of the major threats to the growth and productivity of crop plants. Currently, instead of synthetic fungicides, the use of plant growth-promoting bacterial endophytes has been considered intriguingly eco-friendly in nature. Here, we aimed to investigate the in vitro and in vivo antagonistic approach by using seed-borne endophyticBacillus amyloliquefaciensRWL-1 against pathogenicFusarium oxysporumf. sp.lycopersici. The results revealed significant suppression of pathogenic fungal growth byBacillus amyloliquefaciensin vitro. Further to this, we inoculated tomato plants with RWL-1 andF. oxysporumf. sp.lycopersiciin the root zone. The results showed that the growth attributes and biomass were significantly enhanced by endophytic-inoculation during disease incidence as compared toF. oxysporumf. sp.lycopersiciinfected plants. Under pathogenic infection, the RWL-1-applied plants showed increased amino acid metabolism of cell wall related (e.g., aspartic acid, glutamic acid, serine (Ser), and proline (Pro)) as compared to diseased plants. In case of endogenous phytohormones, significantly lower amount of jasmonic acid (JA) and higher amount of salicylic acid (SA) contents was recorded in RWL-1-treated diseased plants. The phytohormones regulation in disease incidences might be correlated with the ability of RWL-1 to produce organic acids (e.g., succinic acid, acetic acid, propionic acid, and citric acid) during the inoculation and infection of tomato plants. The current findings suggest that RWL-1 inoculation promoted and rescued plant growth by modulating defense hormones and regulating amino acids. This suggests that bacterial endophytes could be used for possible control ofF. oxysporumf. sp.lycopersiciin an eco-friendly way.

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INFLUENCE OF BIOCIDES ON NITRIFICATION, DENITRIFICATION, AND TOMATO N UPTAKE

HortScience ◽

10.21273/hortsci.26.6.703c ◽

1991 ◽

Vol 26 (6) ◽

pp. 703C-703

Author(s):

Zana C. Somda ◽

Harry A. Mills ◽

Sharad C. Phatak

Keyword(s):

Plant Growth ◽

Plant Biomass ◽

N Uptake ◽

Nitrification Inhibitors ◽

Inhibitory Effects ◽

N Transformations ◽

Tomato Plants ◽

Inhibition Of Nitrification ◽

Biological Nitrification

As a result of long-term application, some fungicides may accumulate in the soil to levels that can affect soil N transformations and plant growth. Studies were initiated to compare benomyl, captan, and lime-sulfur fungicides with the biological nitrification inhibitors (NI) nitrapyrin and terrazole for their effects on biological nitrification and denitrification, and tomato (Lycopersicon esculentum Mill.) growth and N uptake. In laboratory studies, inhibition of nitrification was less than 5% in a Tifton l.s. soil incubated with 10 μg g -1 a.i. of benomyl but was about 51%, 72%, and more than 85% when amended with lime-sulfur, captan, and NI, respectively. Similarly, increased inhibitory effects on denitrification of NO3 were obtained in a liquid media incubated anaerobically with either NI (37%) than captan or lime-sulfur (25%) while benomyl had no significant effect. In greenhouse studies with tomato plants, weekly drench applications of 0.25 μg a.i. g -1 soil of the appropriate chemical for 4 weeks with three NH4:NO3 ratios showed that the NI and captan produced the greatest plant biomass and N uptake, but benomyl and lime-sulfur had no main effect while all fungicides interacted with the N ratio to affect plant growth and N uptake.

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Application of seaweed organic components increases tolerance to Fe deficiency in tomato plants

10.1101/553917 ◽

2019 ◽

Author(s):

Sandra Carrasco-Gil ◽

Raúl Allende-Montalbán ◽

Lourdes Hernández-Apaolaza ◽

Juan José Lucena

Keyword(s):

Plant Growth ◽

Organic Compounds ◽

Growth Promotion ◽

Abiotic Stress Tolerance ◽

Fe Deficiency ◽

Tomato Plants ◽

Hydroponic System ◽

Beneficial Effects ◽

Relevant Role ◽

The Individual

AbstractThe beneficial effects of seaweed extracts have been related to plant growth regulators present in seaweeds. However, algae extracts comprise other organic compounds such as phenols, mannitol, alginates, laminarins and fucoidans that may have a relevant role regarding abiotic stress tolerance due to Fe deficiency. Therefore, we evaluated the individual effect of these organic compounds on the mitigation of Fe deficiency applying a range of concentrations (x1/10, x1, x10) in agar Petri dishes (in tomato seeds) and in the nutrient solution of a hydroponic system (tomato plants). Germination and plant growth promotion, root morphology, chlorophyll content and antioxidant activity were determined. Results showed that the lowest concentration x1/10 and phenolics, laminarin and fucose compounds contributed to increase the tolerance to Fe deficiency in tomato plants.

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Comparison of Cabbage Seedling Growth in Four Transplant Production Systems

HortScience ◽

10.21273/hortsci.33.6.976 ◽

1998 ◽

Vol 33 (6) ◽

pp. 976-979 ◽

Cited By ~ 5

Author(s):

Jonathan M. Frantz ◽

Gregory E. Welbaum ◽

Zhengxing Shen ◽

Ron Morse

Keyword(s):

Plant Growth ◽

Leaf Area ◽

Water Availability ◽

Production Systems ◽

Root Zone ◽

Control Plant ◽

Seedling Mortality ◽

Hydroponic System ◽

Black Plastic ◽

And Control

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Biocompatibility of Wheat and Tomato in a Dual Culture Hydroponic System

HortScience ◽

10.21273/hortsci.29.10.1164 ◽

1994 ◽

Vol 29 (10) ◽

pp. 1164-1165 ◽

Cited By ~ 4

Author(s):

Andrew C. Schuerger ◽

Philip D. Laible

Keyword(s):

Triticum Aestivum ◽

Plant Growth ◽

Dry Weight ◽

Fruit Weight ◽

Dual Culture ◽

Lettuce Seedling ◽

Tomato Plants ◽

Hydroponic System ◽

Hydroponic Systems ◽

Allelopathic Compound

`Yecora Rojo' Wheat (Triticum Aestivum L.) And `Florida Petite' Tomato (Lycoper-Sicon Esculentum Mill.) Plants Were Grown In Monocultured Or Intercropped Recirculating Hydroponic Systems To Determine Whether Plant Growth Or Yield Would Be Affected By Intercropping. Mean Fruit Weight Was Slightly Lower (12%) For Intercropped Than For Monocultured Tomato Plants. The Number Of Tillers Per Plant Was Slightly Lower (7%) For Wheat, And Grain Dry Weight Per Plant And Mean Seed Dry Weight Were Slightly Higher (14% And 15%, Respectively) For Intercropped Than For Monocultured Plants. A Lettuce Seedling Bioassay Showed No Evidence Of Allelopathic Compound Accumulation In Monocultured Or Intercropped Hydroponic Systems.

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Effects of Within-row Intercropping with Snow Peas on Yield and Quality of Cherry Tomatoes in an Organic High Tunnel Production System

HortScience ◽

10.21273/hortsci15112-20 ◽

2020 ◽

Vol 55 (11) ◽

pp. 1730-1736

Author(s):

Yun Kong ◽

Katherine Schiestel ◽

David Llewellyn ◽

Youbin Zheng

Keyword(s):

Plant Growth ◽

Production System ◽

Fruit Yield ◽

Dry Matter Content ◽

Cherry Tomato ◽

Tomato Plants ◽

High Tunnel ◽

Yield And Quality ◽

Cherry Tomatoes

Intercropping can increase land use efficiency in high tunnel crop production, but it may also lead to decreases in yield and quality of main crops due to the potential competition for resources. This study evaluated the agronomic viability of intercropping snow pea (Pisum sativum L., ‘Ho Lan Dou’) with cherry tomato (Solanum lycopersicum L. var. cerasiforme ‘Sarina hybrid’) without additional inputs of water and fertilizers on peas in an organic high tunnel production system under Southern Ontario climate conditions in Guelph, Ontario, Canada (lat. 43.5 °N, long. 80.2 °W) during 2015 and 2016. In each 80-cm-wide bed, the tomato crops were planted alternately in double rows spaced 30 cm apart, with in-row spacing of 110 cm, which resulted in a planting density of ≈24,000 plants/ha. The snow pea seeds were sown between the tomato plants (i.e., within the same beds as tomatoes) in holes (two seeds per hole), with four rows in each bed and in-row holes spaced 10 cm and at least 25 cm away from the tomato plants, which resulted in a seeding rate of ≈650, 000 seeds/ha. The same amount of water or fertilizer was applied to the intercropping and nonintercropping plots based on the needs of the cherry tomato plants. Plant growth, fruit yield, and quality were compared between tomato plants with and without intercropping. Intercropping with snow peas did not affect total marketable fruit yield, unmarketable fruit percentage, fruit quality traits (e.g., individual fruit weight, soluble solids content, dry matter content, and postharvest water loss), or early-stage plant growth of the cherry tomato. Therefore, it is at least an agronomical possibility to intercrop snow peas with cherry tomatoes on the same beds without additional inputs of water and fertilizer on snow peas in an organic high tunnel system. The additional yield of pea shoots or pods in the intercropping treatment also increased economic gross returns in the high tunnels, although the economic net return might vary with the costs of seeds and labor involved in snow pea growing.

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