Putrescine biosynthetic pathways modulate root growth differently in tomato seedlings grown under different N sources

Agriculture is the main economic activity responsible for the highest rates of water consumption worldwide. Understanding strategies that combine decreasing the amount of water available and reducing the addition of chemical fertilizers is a major challenge today. Within this context, the work aimed to evaluate the efficiency in promoting growth in tomato seedlings, inoculated with Serratia nematodiphila, submitted to different water deficit conditions. The methodology consisted of using tomato seeds cv. Santa Clara Miss Brasil previously disinfected and inoculated with the Serratia nematodiphila bacterium. The experimental design was completely randomized in the factorial scheme 2 (with bacteria and without bacteria) x 3 (irrigation levels: 100%, 50% and 25% water), making a total of 6 treatments with 6 repetitions. When evaluating the effect of the bacteria Serratia nematodiphila in the treatment with irrigation to 25% of water, it was observed that the average values of the root length of the tomato seedlings was the one that suffered the most stimulus in the root growth when compared to the other irrigation levels. These results suggest that under conditions of greater water deficit the bacteria is able to mitigate drought by promoting root growth.

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Target Tissue for Napropamide Inhibition: Effects on Green and White Callus Cultures and Seedlings

Weed Science ◽

10.1017/s0043174500064870 ◽

1978 ◽

Vol 26 (6) ◽

pp. 711-713 ◽

Cited By ~ 14

Author(s):

S. Zilkah ◽

P. F. Bocion ◽

J. Gressel

Keyword(s):

Lycopersicon Esculentum ◽

Root Growth ◽

Shoot Growth ◽

Foliar Application ◽

Callus Cultures ◽

Target Tissue ◽

Rumex Obtusifolius ◽

Tomato Seedlings ◽

Green Tissue

We previously reported that napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] was highly toxic to achlorophyllous callus of tomato (Lycopersicon esculentum Mill. ‘San Marzano’), whereas foliar application to seedlings was almost without effect. Experiments were performed to ascertain the effects of napropamide on green and achlorophyllous calli of tomato and broadleaf dock (Rumex obtusifolius L.). The growth of achlorophyllous tissues was more severely inhibited. Foliar applications were not as inhibitory in both species. Napropamide was applied to tomato seedlings via roots and cut shoots and root growth was more inhibited than shoot growth. Thus napropamide is toxic to achlorophyllous tissue and is either less toxic to, or detoxified by green tissue.

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Root growth in tomato seedlings in response to bacterial inoculation Serratia sp.

Research Society and Development ◽

10.33448/rsd-v9i7.3634 ◽

2020 ◽

Vol 9 (7) ◽

pp. e89973634

Author(s):

Ana Carla Pinheiro Lima ◽

Leonardo Oliveira Medici ◽

Débora Alves Gonzaga da Silva Ballesteiro Pereira ◽

Eduardo de Assis Lima

Keyword(s):

Root Growth ◽

Water Movement ◽

Growth Promotion ◽

Water Restriction ◽

Negative Effects ◽

Tomato Root ◽

Tomato Seedlings ◽

Solanum Lycopersicum L ◽

Different Doses

Growth-promoting rhizobacteria are soil bacteria that inhabit the surrounding root, and are directly or indirectly involved in promoting plant growth and development. The productivity efficiency of these groups of microorganisms can be applied to planting crops, providing an interesting alternative for minimize the negative effects of water deficit. The objective of this study was to verify if the mechanism of growth promotion of the bacterium is similar to that promoted by polyethylene glycol (PEG) and to compare the possible effects of water stress on the tomato against the effects of inoculation of the bacterium Serratia sp. The methodology was based on in vitro bioassays using tomato (Solanum lycopersicum L.) seedlings, kept in a growth chamber with temperature of 25 °C and photoperiod of 12 hours. The results revealed that the promotion of tomato root growth by Serratia sp. is similar to that promoted by PEG 7%, differing significantly from the results found with different doses of indoleacetic acid (IAA). The promotion of root growth in tomatoes by Serratia sp. and PEG 7% partly indicates a physical effect, since the water restriction imposed by the PEG molecule decreases the water movement capacity, also observed by bacteria, when colonizing plant tissues and cells (biofilm) reducing the hydraulic conductivity of water through the root. Stimulation to promote root growth in tomatoes cannot be reproduced by auxin.

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Effect of CO2 Elevation on Root Growth and Its Relationship with Indole Acetic Acid and Ethylene in Tomato Seedlings

Pedosphere ◽

10.1016/s1002-0160(09)60151-x ◽

2009 ◽

Vol 19 (5) ◽

pp. 570-576 ◽

Cited By ~ 22

Author(s):

Yue WANG ◽

Shao-Ting DU ◽

Ling-Ling LI ◽

Li-Dong HUANG ◽

Ping FANG ◽

...

Keyword(s):

Acetic Acid ◽

Root Growth ◽

Indole Acetic Acid ◽

Tomato Seedlings ◽

Co2 Elevation

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2,4-Diacetylphloroglucinol Alters Plant Root Development

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-21-10-1349 ◽

2008 ◽

Vol 21 (10) ◽

pp. 1349-1358 ◽

Cited By ~ 87

Author(s):

Jessica N. Brazelton ◽

Emily E. Pfeufer ◽

Teresa A. Sweat ◽

Brian B. McSpadden Gardener ◽

Catharina Coenen

Keyword(s):

Root Growth ◽

Plant Root ◽

Primary Root ◽

Luciferase Reporter ◽

Root Production ◽

Inhibitory Effects ◽

Luciferase Reporter Gene ◽

Root Branching ◽

Tomato Seedlings ◽

Primary Root Growth

Pseudomonas fluorescens isolates containing the phlD gene can protect crops from root pathogens, at least in part through production of the antibiotic 2,4-diacetylphloroglucinol (DAPG). However, the action mechanisms of DAPG are not fully understood, and effects of this antibiotic on host root systems have not been characterized in detail. DAPG inhibited primary root growth and stimulated lateral root production in tomato seedlings. Roots of the auxin-resistant diageotropica mutant of tomato demonstrated reduced DAPG sensitivity with regards to inhibition of primary root growth and induction of root branching. Additionally, applications of exogenous DAPG, at concentrations previously found in the rhizosphere of plants inoculated with DAPG-producing pseudomonads, inhibited the activation of an auxin-inducible GH3 promoter∷luciferase reporter gene construct in transgenic tobacco hypocotyls. In this model system, supernatants of 17 phlD+ P. fluorescens isolates had inhibitory effects on luciferase activity similar to synthetic DAPG. In addition, a phlD– mutant strain, unable to produce DAPG, demonstrated delayed inhibitory effects compared with the parent wild-type strain. These results indicate that DAPG can alter crop root architecture by interacting with an auxin-dependent signaling pathway.

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Root growth of tomato seedlings intensified by humic substances from peat bogs

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832011000500015 ◽

2011 ◽

Vol 35 (5) ◽

pp. 1609-1617 ◽

Cited By ~ 6

Author(s):

Alexandre Christofaro Silva ◽

Luciano Pasqualoto Canellas ◽

Fábio Lopes Olivares ◽

Leonardo Barros Dobbss ◽

Natalia Oliveira Aguiar ◽

...

Keyword(s):

Root Growth ◽

Humic Substances ◽

Root Hair ◽

Growth Promotion ◽

Lateral Roots ◽

Peat Bogs ◽

Response Curves ◽

Tomato Seedlings ◽

Root Hair Formation ◽

Hair Formation

Peats are an important reserve of humified carbon in terrestrial ecosystems. The interest in the use of humic substances as plant growth promoters is continuously increasing. The objective of this study was to evaluate the bioactivity of alkaline soluble humic substances (HS), humic (HA) and fulvic acids (FA) isolated from peats with different decomposition stages of organic matter (sapric, fibric and hemic) in the Serra do Espinhaço Meridional, state of Minas Gerais. Dose-response curves were established for the number of lateral roots growing from the main plant axis of tomato seedlings. The bioactivity of HA was greatest (highest response in lateral roots at lowest concentration) while FA did not intensify root growth. Both HS and HA stimulated root hair formation. At low concentrations, HS and HA induced root hair formation near the root cap, a typical hormonal imbalance effect in plants. Transgenic tomato with reporter gene DR5::GUS allowed the observation that the auxin-related signalling pathway was involved in root growth promotion by HA.

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Interrelation of root and shoot temperatures on dry matter accumulation and root growth in tomato seedlings

Journal of Horticultural Science ◽

10.1080/14620316.1987.11515747 ◽

1987 ◽

Vol 62 (1) ◽

pp. 49-54 ◽

Cited By ~ 2

Author(s):

Martha Maletta ◽

H. W. Janes

Keyword(s):

Root Growth ◽

Dry Matter ◽

Dry Matter Accumulation ◽

Tomato Seedlings

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Trichoderma atroviride LZ42 Releases Volatile Organic Compounds Promoting Plant Growth and Resisting Fusarium wilt Disease in Tomatoes

10.20944/preprints202109.0309.v1 ◽

2021 ◽

Author(s):

Hong Jiang ◽

Yuxin Rao ◽

Linzhou Zeng ◽

Li Mei ◽

Yongjun Wang

Keyword(s):

Volatile Organic Compounds ◽

Plant Growth ◽

Root Growth ◽

Organic Compounds ◽

Fusarium Wilt ◽

Wilt Disease ◽

Tomato Seedlings ◽

Fusarium Wilt Disease ◽

Primary Roots ◽

Volatile Organic

The promotion of plant growth and suppression of plant disease using beneficial microorganisms is considered an alternative to the application of chemical fertilizers or pesticides in the field. In this study, a coconut-scented antagonistic Trichoderma strain LZ42, previously isolated from Genoderma lucidum-cultivated soil, was investigated for biostimulatory and biocontrol functions in tomato seedlings. Morphological and phylogenetic analyses suggested that strain LZ42 is closely related to T. atroviride. Tomato plants showed increased aerial and root dry weights in greenhouse trials after treatment with T. atroviride LZ42 formulated in talc, indicating the biostimulatory function of this fungus. T. atroviride LZ42 effectively suppressed Fusarium wilt disease in tomato seedlings, with an 82.69% control efficiency, which is similar to that of fungicide treatment. The volatile organic compounds (VOCs) emitted by T. atroviride LZ42 were found to affect the primary root growth direction and promote the root growth of tomato seedlings in root Y-tube olfactometer assays. The fungal VOCs from T. atroviride LZ42 were observed to significantly inhibit F. oxysporum in a sandwiched Petri dish assay. SPME-GC-MS analysis revealed several VOCs emitted by T. atroviride LZ42; the dominant compound was tentatively identified as 6-pentyl-2H-pyran-2-one (6-PP). 6-PP exhibited a stronger ability to influence the direction of the primary roots of tomato seedlings but not the length of the primary roots. The inhibitory effect of 6-PP on F. oxysporum was the highest among the tested pure VOCs, showing a 50% effective concentration (EC50) of 5.76 μL mL-1 headspace. In conclusion, T. atroviride LZ42, which emits VOCs with multiple functions, is a promising agent for the biostimulation of vegetable plants and integrated management of Fusarium wilt disease.

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Ambiol Preconditioning Can Induce Drought Tolerance in Abscisic Acid-deficient Tomato Seedlings

HortScience ◽

10.21273/hortsci.44.7.1890 ◽

2009 ◽

Vol 44 (7) ◽

pp. 1890-1894 ◽

Cited By ~ 3

Author(s):

Mason T. MacDonald ◽

Rajasekaran R. Lada ◽

Jeff Hoyle ◽

A. Robin Robinson

Keyword(s):

Abscisic Acid ◽

Lycopersicon Esculentum ◽

Drought Tolerance ◽

Root Growth ◽

Shoot Growth ◽

Growth Promoter ◽

Wild Type ◽

Tomato Seedlings ◽

Use Efficiency ◽

Dependent Pathway

Ambiol, a derivative of 5-hydroxybenzimidazole, has been well documented to function as a growth promoter, an antistress compound, and an antioxidant when applied as a seed preconditioning agent. However, evidence suggests that Ambiol decreases transpiration and promotes root growth similar to the phytohormone abscisic acid (ABA), leading to the development of the hypothesis that Ambiol promotes drought resistance through an ABA-dependent pathway. The effect of 0 mg·L−1 and 10 mg·L−1 was tested on wild-type tomato seedlings (Lycopersicon esculentum Mill. var. Scotia), ABA-deficient flacca tomato seedlings, and ABA-inhibited (with fluridone) tomato seedlings. In both fluridone-treated and flacca seedlings, Ambiol preconditioning resulted in significant increases in shoot growth, root growth, leaf area, and plant height consistent with gains experienced by wild-type tomatoes. In addition, flacca tomatoes experienced increases in photosynthesis and water use efficiency consistent with wild-type tomatoes. Ambiol was able to confer benefits to drought-stressed tomatoes in ABA-deficient and ABA-inhibited conditions, suggesting that Ambiol functions through an ABA-independent pathway.

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