Importance of Daily Rhythms on Brassicaceae Phytochemicals

The circadian clock serves to coordinate metabolism and physiology with the diurnal cycles derived from the daily rotation of the earth. In Brassicaceae, circadian rhythms contribute to the temporal daily variation in diverse phytochemicals and, hence, to both resistance to biotic stress and edible crop health value. Understanding the temporal variation in the specialized metabolites present in Brassica crops can improve selection and future breeding strategies. In this review, we focus on the importance of daily rhythms in the phytochemical biochemistry of the main bioactive compounds present in Brassicaceae plants. We provide a general overview of the mechanisms that can drive the daily variation in phytochemical levels and then provide specific examples of compounds that show daily variation. Finally, we discuss how these rhythmic patterns in plant phytochemicals may impact plant protection against biotic stress, the content of nutraceuticals, and the longevity of post-harvest crops.

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Salicylic acid and its role in induced plant resistance to biotic stress

BULLETIN of the L N Gumilyov Eurasian National University BIOSCIENCE Series ◽

10.32523/2616-7034-2020-131-2-8-14 ◽

2020 ◽

Vol 131 (2) ◽

pp. 8-14

Author(s):

N.N. Iksat ◽

◽

D. Tokasheva ◽

М.К. Beissekova ◽

U.I. Amanbayeva ◽

...

Keyword(s):

Salicylic Acid ◽

Antioxidant Enzymes ◽

Biotic Stress ◽

Plant Protection ◽

Plant Immunity ◽

Review Article ◽

Induced Plant Resistance ◽

Protective Genes ◽

Oxidative Processes ◽

Insight Into

Salicylic acid is a natural signaling molecule that plays a key role in establishing and transmitting plant protection signals from phytopathogens. Salicylic acid, by modulating the expression of protective genes and changing the activity of antioxidant enzymes, can regulate oxidative processes associated with plant protective reactions. This review article reviews studies that provide insight into the functioning of salicylic acid in plant immunity

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Risk Factors for Crop Health Under Global Change and Agricultural Shifts: A Framework of Analyses Using Rice in Tropical and Subtropical Asia as a Model

Phytopathology ◽

10.1094/phyto-07-10-0183 ◽

2011 ◽

Vol 101 (6) ◽

pp. 696-709 ◽

Cited By ~ 24

Author(s):

S. Savary ◽

A. Mila ◽

L. Willocquet ◽

P. D. Esker ◽

O. Carisse ◽

...

Keyword(s):

Risk Factors ◽

Health Risks ◽

Large Scale ◽

Plant Protection ◽

Significant Risk ◽

Global Changes ◽

Agricultural Change ◽

Data Set ◽

Holistic View ◽

Crop Health

Plant disease epidemiology requires expansion of its current methodological and theoretical underpinnings in order to produce full contributions to global food security and global changes. Here, we outline a framework which we applied to farmers' field survey data set on rice diseases in the tropical and subtropical lowlands of Asia. Crop health risks arise from individual diseases, as well as their combinations in syndromes. Four key drivers of agricultural change were examined: labor, water, fertilizer, and land availability that translate into crop establishment method, water shortage, fertilizer input, and fallow period duration, respectively, as well as their combinations in production situations. Various statistical approaches, within a hierarchical structure, proceeding from higher levels of hierarchy (production situations and disease syndromes) to lower ones (individual components of production situations and individual diseases) were used. These analyses showed that (i) production situations, as wholes, represent very large risk factors (positive or negative) for occurrence of disease syndromes; (ii) production situations are strong risk factors for individual diseases; (iii) drivers of agricultural change represent strong risk factors of disease syndromes; and (iv) drivers of change, taken individually, represent small but significant risk factors for individual diseases. The latter analysis indicates that different diseases are positively or negatively associated with shifts in these drivers. We also report scenario analyses, in which drivers of agricultural change are varied in response to possible climate and global changes, generating predictions of shifts in rice health risks. The overall set of analyses emphasizes the need for large-scale ground data to define research priorities for plant protection in rapidly evolving contexts. They illustrate how a structured theoretical framework can be used to analyze emergent features of agronomic and socioecological systems. We suggest that the concept of “disease syndrome” can be borrowed in botanical epidemiology from public health to emphasize a holistic view of disease in shifting production situations in combination with the conventional, individual disease-centered perspective.

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Direct comparison of Arabidopsis gene expression reveals different responses to melatonin versus auxin

BMC Plant Biology ◽

10.1186/s12870-019-2158-3 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 3

Author(s):

Sajal F. Zia ◽

Oliver Berkowitz ◽

Frank Bedon ◽

James Whelan ◽

Ashley E. Franks ◽

...

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Biotic Stress ◽

Plant Protection ◽

Normal Growth ◽

Direct Repeat ◽

Growth Conditions ◽

Differentially Expressed ◽

Naphthalene Acetic Acid ◽

Regulatory Pathways

Abstract Background Melatonin (N-acetyl-5-methoxytryptamine) in plants, regulates shoot and root growth and alleviates environmental stresses. Melatonin and the phyto-hormone auxin are tryptophan-derived compounds. However, it largely remains controversial as to whether melatonin and auxin act through similar or overlapping signalling and regulatory pathways. Results Here, we have used a promoter-activation study to demonstrate that, unlike auxin (1-naphthalene acetic acid, NAA), melatonin neither induces Direct repeat 5 DR5 expression in Arabidopsis thaliana roots under normal growth conditions nor suppresses the induction of Alternative oxidase 1a AOX1a in leaves upon Antimycin A treatment, both of which are the hallmarks of auxin action. Additionally, comparative global transcriptome analysis conducted on Arabidopsis treated with melatonin or NAA revealed differences in the number and types of differentially expressed genes. Auxin (4.5 μM) altered the expression of a diverse and large number of genes whereas melatonin at 5 μM had no significant effect but melatonin at 100 μM had a modest effect on transcriptome compared to solvent-treated control. Interestingly, the prominent category of genes differentially expressed upon exposure to melatonin trended towards biotic stress defence pathways while downregulation of key genes related to photosynthesis was observed. Conclusion Together these findings indicate that though they are both indolic compounds, melatonin and auxin act through different pathways to alter gene expression in Arabidopsis thaliana. Furthermore, it appears that effects of melatonin enable Arabidopsis thaliana to prioritize biotic stress defence signalling rather than growth. These findings clear the current confusion in the literature regarding the relationship of melatonin and auxin and also have greater implications of utilizing melatonin for improved plant protection.

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Adaptive periodicity in the infectivity of malaria gametocytes to mosquitoes

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.1876 ◽

2018 ◽

Vol 285 (1888) ◽

pp. 20181876 ◽

Cited By ~ 12

Author(s):

Petra Schneider ◽

Samuel S. C. Rund ◽

Natasha L. Smith ◽

Kimberley F. Prior ◽

Aidan J. O'Donnell ◽

...

Keyword(s):

Blood Parasite ◽

Parasite Development ◽

Bed Nets ◽

Immune Defence ◽

Mosquito Vectors ◽

Molecular Processes ◽

Daily Rhythms ◽

The Earth ◽

Rotation Of The Earth ◽

Biting Time

Daily rhythms in behaviour, physiology and molecular processes are expected to enable organisms to appropriately schedule activities according to consequences of the daily rotation of the Earth. For parasites, this includes capitalizing on periodicity in transmission opportunities and for hosts/vectors, this may select for rhythms in immune defence. We examine rhythms in the density and infectivity of transmission forms (gametocytes) of rodent malaria parasites in the host's blood, parasite development inside mosquito vectors and potential for onwards transmission. Furthermore, we simultaneously test whether mosquitoes exhibit rhythms in susceptibility. We reveal that at night, gametocytes are twice as infective, despite being less numerous in the blood. Enhanced infectiousness at night interacts with mosquito rhythms to increase sporozoite burdens fourfold when mosquitoes feed during their rest phase. Thus, changes in mosquito biting time (owing to bed nets) may render gametocytes less infective, but this is compensated for by the greater mosquito susceptibility.

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The Influence of Host Plants on Herbivore Community Composition on Brassica Crops in Western Siberia

ISRN Botany ◽

10.5402/2012/682474 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

M. V. Shternshis ◽

I. V. Andreeva ◽

E. I. Shatalova

Keyword(s):

Brassica Oleracea ◽

Western Siberia ◽

Plant Protection ◽

Red Cabbage ◽

Brassica Crops ◽

White Cabbage ◽

Herbivore Community ◽

The Common ◽

Plant Herbivore ◽

Biological Insect Control

Experiments on three varieties of Brassica oleracea (white cabbage, red cabbage, and cauliflower) were conducted during the years 2008–2011 in Western Siberia (Russia) to study the influence of host plant on herbivore infestation. The results revealed the evidence of different infestation of white cabbage, red cabbage, and cauliflower by the common herbivores in Western Siberia. Flea beetles as the earliest herbivores preferred to infest white cabbage. Contrary to those herbivores, M. brassicae and P. xylostella larvae infested red cabbage most of all. The latest herbivore of all plants studied, P. brassicae, preferred cauliflower but not red cabbage. The possible contribution of some factors in summary effects observed in the study was discussed. Further studies are being planned in which tritrophic interaction including B. oleracea plant, herbivore, and microbial insecticides should be investigated. These studies will help to develop biological insect control on Brassica oleracea crops in order to supply ecologically safe plant protection.

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Daily intervals of heat exposure alter the phase of the daily variation of plasma hormones in Holtzman rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1993.265.5.r1115 ◽

1993 ◽

Vol 265 (5) ◽

pp. R1115-R1120

Author(s):

C. J. De Souza ◽

A. H. Meier

Keyword(s):

Food Consumption ◽

Daily Variation ◽

Plasma Concentrations ◽

Heat Exposure ◽

Daily Rhythms ◽

Light Onset ◽

Glucose And Lipid Metabolism ◽

Body Weights ◽

Fat Stores ◽

Plasma Hormones

The effects of timed daily increases in ambient temperature (thermopulses) (from 22 +/- 1 to 40 +/- 1 degree C for 2 h) on daily variations of hormones involved in glucose and lipid metabolism were tested in male Holtzman rats (3-4 mo old) exposed to a 12-h daily photoperiod. The thermopulses were administered for 14 days either at light onset (TP0) or 16 h after light onset (TP16). Body weights and food consumption were monitored during the experiment. Retroperitoneal fat weights and plasma concentrations of insulin, glucose, glucagon, corticosterone, and prolactin were determined from blood taken every 4 h during a 24-h period commencing 24 h after the last thermopulse. TP0 treatment did not alter any of the parameters tested. Conversely, TP16 treatment obliterated the daily rhythms of insulin and corticosterone present in the controls (nonthermopulsed) and decreased body weight gains, retroperitoneal fat stores, food consumption, and the baseline levels of plasma insulin and corticosterone. The present study supports a role for circadian neuroendocrine rhythms in the reduction of fat stores induced by properly timed daily thermopulses.

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Biosecurity: tools, behaviours and concepts

Emerging Topics in Life Sciences ◽

10.1042/etls20200343 ◽

2020 ◽

Vol 4 (5) ◽

pp. 449-452

Author(s):

Alan MacLeod ◽

Nicola Spence

Keyword(s):

Plant Protection ◽

Human Life ◽

Animal Health ◽

Early Warning Systems ◽

Policy Makers ◽

Recent Developments ◽

Surveillance Programs ◽

Harmful Organisms ◽

The One ◽

Biosecurity Practices

COVID 19 has raised the profile of biosecurity. However, biosecurity is not only about protecting human life. This issue brings together mini-reviews examining recent developments and thinking around some of the tools, behaviours and concepts around biosecurity. They illustrate the multi-disciplinary nature of the subject, demonstrating the interface between research and policy. Biosecurity practices aim to prevent the spread of harmful organisms; recognising that 2020 is the International Year of Plant Health, several focus on plant biosecurity although invasive species and animal health concerns are also captured. The reviews show progress in developing early warning systems and that plant protection organisations are increasingly using tools that compare multiple pest threats to prioritise responses. The bespoke modelling of threats can inform risk management responses and synergies between meteorology and biosecurity provide opportunities for increased collaboration. There is scope to develop more generic models, increasing their accessibility to policy makers. Recent research can improve pest surveillance programs accounting for real-world constraints. Social science examining individual farmer behaviours has informed biosecurity policy; taking a broader socio-cultural approach to better understand farming networks has the potential to change behaviours in a new way. When encouraging public recreationists to adopt positive biosecurity behaviours communications must align with their values. Bringing together the human, animal, plant and environmental health sectors to address biosecurity risks in a common and systematic manner within the One Biosecurity concept can be achieved through multi-disciplinary working involving the life, physical and social sciences with the support of legislative bodies and the public.

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