The role of temperature in the development of blue mould (Peronospora tabacina Adam)  Disease in tobacco seedlings. III. The effect of pre-inoculation temperature and of shade on plant growth and disease development

The spread and effect on plant growth of blue mould disease of tobacco was measured on cv. Virginia Gold and SO1 under controlled conditions. The factors considered were the effect of three pre-inoculation temperatures on response to post-inoculation temperature and the direct effects of shade under three temperature regimes. Different pre-inoculation temperatures did not modify significantly the response to inoculation at three post-inoculation temperatures. As post-inoculation temperature increased, the amount of stem mould decreased and the sizes of both healthy and inoculated plants increased. The effects of pre-inoculation temperature on plant growth persisted to the end of the experiments. Only for the stem length of healthy plants was there a significant interaction with post-inoculation temperature, and even then the stem length increased for all post-inoculation temperatures. Under the two higher temperature regimes shaded plants were smaller than unshaded. Shaded and unshaded plants held at the same temperature were equally susceptible to blue mould.

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The role of temperature in the development of blue mould (Peronospora tabacina Adam.) disease in tobacco seedlings. II. Effect on plant growth

Australian Journal of Agricultural Research ◽

10.1071/ar9650609 ◽

1965 ◽

Vol 16 (4) ◽

pp. 609 ◽

Cited By ~ 1

Author(s):

AV Hill

Keyword(s):

Plant Growth ◽

Leaf Size ◽

Stem Length ◽

Peronospora Tabacina ◽

Tobacco Plants ◽

Temperature Regimes ◽

Affected Plant ◽

Wide Range ◽

Tobacco Seedlings ◽

Stem Necrosis

Healthy tobacco plants and tobacco plants inoculated with conidia of Peronospora tabacina were subjected to a wide range of temperature conditions. Two strains of the pathogen were used. Both affected plant growth, the greatest and most obvious effects being at night temperatures of 16–24°C. Growth, as measured by stem length, leaf number, and leaf size in plants inoculated with strain APT2, was limited by stem necrosis rather than by leaf necrosis. There was less stem necrosis at the higher day temperatures and fewer dead leaves at all temperature regimes, with strain APT2 than with APT1. At high day temperatures, stem necrosis tended to be restricted to the region of the external phloem, with consequently less severe effects on growth.

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The role of temperature in the development of blue mould (Peronospora tabacina Adam) disease in tobacco seedlings. I. In leaves

Australian Journal of Agricultural Research ◽

10.1071/ar9650597 ◽

1965 ◽

Vol 16 (4) ◽

pp. 597 ◽

Cited By ~ 2

Author(s):

AV Hill ◽

S Green

Keyword(s):

Narrow Range ◽

Peronospora Tabacina ◽

Progressive Development ◽

Blue Mould ◽

Temperature Conditions ◽

Strong Trend ◽

Slow Development ◽

Wide Range ◽

Tobacco Seedlings

In tests over a wide range of temperature conditions the number of days from inoculation of plants of cv. Virginia Gold with conidia of Peronospora tabacina to appearance of blue mould symptoms in leaves varied from 4 to 12 days with conidia of strain APT1 and from 5 to 15 days with strain APT2. It was 4 to 14 days with strain APT2 on plants of cv. SO1. Initial death of leaves of cv. Virginia Gold occurred at 5–6 days after inoculation with APT1 but 3–4 days later when similar plants or cv. SO1 were inoculated with APT2. For each strain there was a strong trend toward similar leaf loss, and similar progressive development of leaf loss in treatments with the same night temperatures. For both strains, leaf losses developed most rapidly and were most severe at night temperatures of 16–24°C. The relatively slow development of APT2, except over a narrow range of temperatures, would limit its capacity for competing with APT1 and for producing epiphytotics.

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Insights into the Interactions among Roots, Rhizosphere, and Rhizobacteria for Improving Plant Growth and Tolerance to Abiotic Stresses: A Review

Cells ◽

10.3390/cells10061551 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1551

Author(s):

Naeem Khan ◽

Shahid Ali ◽

Muhammad Adnan Shahid ◽

Adnan Mustafa ◽

R. Z. Sayyed ◽

...

Keyword(s):

Plant Growth ◽

Abiotic Stresses ◽

Growth And Development ◽

Direct Effects ◽

Complex Root ◽

Plant Tolerance ◽

Plant Growth And Development ◽

Growth Promoting ◽

Underlying Mechanisms

Abiotic stresses, such as drought, salinity, heavy metals, variations in temperature, and ultraviolet (UV) radiation, are antagonistic to plant growth and development, resulting in an overall decrease in plant yield. These stresses have direct effects on the rhizosphere, thus severely affect the root growth, and thereby affecting the overall plant growth, health, and productivity. However, the growth-promoting rhizobacteria that colonize the rhizosphere/endorhizosphere protect the roots from the adverse effects of abiotic stress and facilitate plant growth by various direct and indirect mechanisms. In the rhizosphere, plants are constantly interacting with thousands of these microorganisms, yet it is not very clear when and how these complex root, rhizosphere, and rhizobacteria interactions occur under abiotic stresses. Therefore, the present review attempts to focus on root–rhizosphere and rhizobacterial interactions under stresses, how roots respond to these interactions, and the role of rhizobacteria under these stresses. Further, the review focuses on the underlying mechanisms employed by rhizobacteria for improving root architecture and plant tolerance to abiotic stresses.

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The role of endophytic bacteria and mycorrhizae fungus as plant growth inducer of white turmeric

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/759/1/012025 ◽

2021 ◽

Vol 759 (1) ◽

pp. 012025

Author(s):

R Simarmata ◽

Nuriyanah ◽

L Nurjanah ◽

J R L Sylvia ◽

T Widowati

Keyword(s):

Plant Growth ◽

Endophytic Bacteria

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The Role of Flexibility in the Realization of Inclusive Education

Sustainability ◽

10.3390/su13084452 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4452

Author(s):

Laura Lübke ◽

Martin Pinquart ◽

Malte Schwinger

Keyword(s):

Social Skills ◽

Inclusive Education ◽

Learning Difficulties ◽

Social Benefits ◽

Direct Effects ◽

Behavioral Disturbances ◽

Teachers Attitudes ◽

And Behavior ◽

Mainstream Students

This study focused on associations between teachers’ flexibility and their use of evidence-based strategies in inclusive education in a sample of N = 119 teachers. Flexibility showed direct effects on teachers’ attitudes towards the achievement of mainstream students and students with learning difficulties, attitudes towards social benefits of inclusion for students with emotional and behavioral disturbances, and on teachers’ self-efficacy regarding the support of students’ social skills. Furthermore, indirect effects of flexibility on intentions and behavior regarding the support of social skills were found. The findings emphasize the importance of teachers’ flexibility in the realization of inclusive education.

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Role of GABA in plant growth, development and senescence

Plant Gene ◽

10.1016/j.plgene.2021.100283 ◽

2021 ◽

Vol 26 ◽

pp. 100283

Author(s):

M. Iqbal R. Khan ◽

Syed Uzma Jalil ◽

Priyanka Chopra ◽

Himanshu Chhillar ◽

Antonio Ferrante ◽

...

Keyword(s):

Plant Growth ◽

Growth Development

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Recapitulation of the Function and Role of ROS Generated in Response to Heat Stress in Plants

Plants ◽

10.3390/plants10020371 ◽

2021 ◽

Vol 10 (2) ◽

pp. 371

Author(s):

Emily Medina ◽

Su-Hwa Kim ◽

Miriam Yun ◽

Won-Gyu Choi

Keyword(s):

Heat Stress ◽

Plant Growth ◽

Intracellular Signaling ◽

Oxygen Species ◽

Natural Ecosystems ◽

Signaling Molecule ◽

Signaling Systems ◽

Cell Compartments ◽

Tropical Area

In natural ecosystems, plants are constantly exposed to changes in their surroundings as they grow, caused by a lifestyle that requires them to live where their seeds fall. Thus, plants strive to adapt and respond to changes in their exposed environment that change every moment. Heat stress that naturally occurs when plants grow in the summer or a tropical area adversely affects plants’ growth and poses a risk to plant development. When plants are subjected to heat stress, they recognize heat stress and respond using highly complex intracellular signaling systems such as reactive oxygen species (ROS). ROS was previously considered a byproduct that impairs plant growth. However, in recent studies, ROS gained attention for its function as a signaling molecule when plants respond to environmental stresses such as heat stress. In particular, ROS, produced in response to heat stress in various plant cell compartments such as mitochondria and chloroplasts, plays a crucial role as a signaling molecule that promotes plant growth and triggers subsequent downstream reactions. Therefore, this review aims to address the latest research trends and understandings, focusing on the function and role of ROS in responding and adapting plants to heat stress.

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The Role of Predation in Determining Traits of Aedes aegypti (Diptera: Culicidae) and Infection With Zika Virus

Journal of Medical Entomology ◽

10.1093/jme/tjab004 ◽

2021 ◽

Author(s):

Shawna Bellamy ◽

Barry W Alto

Keyword(s):

Aedes Aegypti ◽

Zika Virus ◽

Life History Traits ◽

Immature Stages ◽

Direct Effects ◽

Infected Blood ◽

Predator Prey ◽

Susceptibility To Infection ◽

Density Reduction

Abstract Non-lethal predator-prey interactions during the immature stages can cause significant changes to mosquito life history traits and their ability to transmit pathogens as adults. Treatment manipulations using mosquitoes Aedes aegypti (L.) and Toxoryhnchites rutilus (Coquillett) were performed during the immature stages to explore the potential impacts of non-lethal interactions on adult susceptibility to infection, disseminated infection and saliva infection of Ae. aegypti following ingestion of Zika virus-infected blood. Treatments inducing density reduction resulted in reduced development time and survivorship to adulthood. However, effects of treatment did not alter infection, dissemination, or saliva infection. These observations indicate that, while non-lethal predation may impact some traits that influence population dynamics and transmission of pathogens, there were no direct effects on mosquito-arbovirus interactions.

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