Long‐term adaptation of Arabidopsis thaliana to Far‐red light

Abstract West Nile virus (WNV) is the most prevalent arbovirus found throughout the United States. Surveillance of surface breeding Culex vectors involved in WNV transmission is primarily conducted using CDC Gravid traps. However, anecdotal claims from mosquito abatement districts in Louisiana assert that other trap types may be more suited to WNV surveillance. To test the validity of these assertions, we conducted a series of trapping trials and WNV surveillance over 3 yr to compare the efficacy of multiple trap types. First, we compared the CDC Gravid trap, CO2-baited New Standard Miniature Blacklight traps, and CO2-baited CDC light traps with either an incandescent light, a red light, or no light. We found that the CDC Gravid trap and CO2-baited no-light CDC Light trap collected the most mosquitoes. Second, we conducted additional, long-term trapping and WNV surveillance to compare these two trap types. We found that CO2-baited no-light CDC traps collected more of the local WNV vector, Culex quinquefasciatus (Say, Diptera, Culicidae), and detected WNV with greater sensitivity. Finally, we conducted trapping to compare the physiological states of Cx. quinquefasciatus and diversity of collected mosquitoes. CO2-baited no-light CDC light traps collected more unfed Cx. quinquefasciatus while Gravid traps collected more blooded Cx. quinquefasciatus; both traps collected the same number of gravid Cx. quinquefasciatus. Additionally, we found that CO2-baited no-light CDC light traps collected a larger diversity of mosquito species than Gravid traps.

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Impact of AtNHX1, a vacuolar Na+/H+ antiporter, upon gene expression during short- and long-term salt stress in Arabidopsis thaliana

BMC Plant Biology ◽

10.1186/1471-2229-7-18 ◽

2007 ◽

Vol 7 (1) ◽

pp. 18 ◽

Cited By ~ 49

Author(s):

Jordan B Sottosanto ◽

Yehoshua Saranga ◽

Eduardo Blumwald

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Salt Stress ◽

Short And Long Term

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Light Gradient-Based Screening of Arabidopsis thaliana on a 384-Well Type Plant Array Chip

Micromachines ◽

10.3390/mi11020191 ◽

2020 ◽

Vol 11 (2) ◽

pp. 191

Author(s):

Youn-Hee Park ◽

Je-Kyun Park

Keyword(s):

Arabidopsis Thaliana ◽

White Light ◽

Solid Medium ◽

Red Light ◽

Phytochrome B ◽

Wild Type ◽

Light Gradient ◽

Gradient Based ◽

Light Effects ◽

Germination And Growth

Arabidopsis thaliana (Arabidopsis), as a model for plant research, is widely used for various aspects of plant science. To provide a more sophisticated and microscopic environment for the germination and growth of Arabidopsis, we report a 384-well type plant array chip in which each Arabidopsis seed is independently seeded in a solid medium. The plant array chip is made of a poly(methyl methacrylate) (PMMA) acrylic material and is assembled with a home-made light gradient module to investigate the light effects that significantly affect the germination and growth of Arabidopsis. The light gradient module was used to observe the growth pattern of seedlings according to the intensity of the white light and to efficiently screen for the influence of the white light. To investigate the response to red light (600 nm), which stimulates seed germination, the light gradient module was also applied to the germination test. As a result, the germination results showed that the plant array chip can be used to simultaneously screen wild type seeds and phytochrome B mutant seeds on a single array chip according to the eight red light intensities.

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The major photoprotective role of anthocyanins in leaves of Arabidopsis thaliana under long-term high light treatment: antioxidant or light attenuator?

Photosynthesis Research ◽

10.1007/s11120-020-00761-8 ◽

2020 ◽

Author(s):

Xiao-Ting Zheng ◽

Zheng-Chao Yu ◽

Jun-Wei Tang ◽

Min-Ling Cai ◽

Yi-Lin Chen ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Light Treatment ◽

High Light ◽

High Light Treatment

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Arabidopsis chloroplast J protein DJC75/CRRJ mediates nitrate-promoted seed germination in the dark

Annals of Botany ◽

10.1093/aob/mcaa040 ◽

2020 ◽

Vol 125 (7) ◽

pp. 1091-1099

Author(s):

Huai-Syuan Ciou ◽

Yu-Lun Tsai ◽

Chi-Chou Chiu

Keyword(s):

Arabidopsis Thaliana ◽

Seed Germination ◽

Germination Rate ◽

Red Light ◽

Phytochrome B ◽

Biosynthetic Gene ◽

Unknown Mechanism ◽

J Domain ◽

Domain Protein ◽

J Protein

Abstract Background and Aims Nitrate can stimulate seed germination of many plant species in the absence of light; however, the molecular mechanism of nitrate-promoted seed germination in the dark remains largely unclear and no component of this pathway has been identified yet. Here, we show that a plastid J-domain protein, DJC75/CRRJ, in arabidopsis (Arabidopsis thaliana) is important for nitrate-promoted seed germination in the dark. Methods The expression of DJC75 during imbibition in the dark was investigated. The seed germination rate of mutants defective in DJC75 was determined in the presence of nitrate when light cues for seed germination were eliminated by the treatment of imbibed seeds with a pulse of far-red light to inactivate phytochrome B (phyB), or by assaying germination in the dark with seeds harbouring the phyB mutation. The germination rates of mutants defective in CRRL, a J-like protein related to DJC75, and in two chloroplast Hsp70s were also measured in the presence of nitrate in darkness. Key Results DJC75 was expressed during seed imbibition in the absence of light. Mutants defective in DJC75 showed seed germination defects in the presence of nitrate when light cues for seed germination were eliminated. Mutants defective in CRRL and in two chloroplast Hsp70s also exhibited similar seed germination defects. Upregulation of gibberellin biosynthetic gene GA3ox1 expression by nitrate in imbibed phyB mutant seeds was diminished when DJC75 was knocked out. Conclusions Our data suggest that plastid J-domain protein DJC75 regulates nitrate-promoted seed germination in the dark by upregulation of expression of the gibberellin biosynthetic gene GA3ox1 through an unknown mechanism and that DJC75 may work in concert with chloroplast Hsp70s to regulate nitrate-promoted seed germination. DJC75 is the first pathway component identified for nitrate-promoted seed germination in the dark.

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Contrasting seed germination responses to red and far-red light in Leptospermum scoparium and Melicytus ramiflorus

Functional Plant Biology ◽

10.1071/pp00024 ◽

2000 ◽

Vol 27 (11) ◽

pp. 1069

Author(s):

Helen Herron ◽

John Clemens ◽

Dennis H. Greer

Keyword(s):

Seed Germination ◽

Red Light ◽

Green Light ◽

Photon Flux ◽

Short Term ◽

Short Term Exposure ◽

Subsequent Exposure ◽

R:Fr Ratio ◽

Leptospermum Scoparium

Effects of red light (R) and far-red light (FR), and selected photon flux densities (PFD) of photosynthetically active radiation (PAR) on seed germination in the photoblastic, primary colonising species Leptospermum scoparium J. R. et G. Forst. and the late secondary successional Melicytus ramiflorus J. R. et G. Forst. were studied. A continuous R dose response curve forL. scoparium germination was developed, unifying data from experiments using long-term exposure to PAR with those following short-term exposure to R. The threshold R dose needed to effect germination was ~0.1 mmol m –2 , and the response was saturated at 1000 mmol m –2 . Stimulation of germination by R was reversed by a subsequent exposure to FR. These features are consistent with a low-fluence response mediated by phytochrome B. FR reversal of germination was achieved at a dose two orders of magnitude lower than that of R required to induce initial germination. However, when both R and FR were provided simultaneously, the FR dose needed to even partially inhibit germination (34% compared to > 95% in controls) was two orders of magnitude higher than the R dose (R:FR ratio = 0.007). Germination in L. scoparium was also stimulated in up to 12% of seed upon diurnal exposure to FR, or by green light (~2 mol m –2 ), indicating a very-low-fluence response mediated by phytochrome A also operating in this species. In contrast, seed germination in M. ramiflorus was relatively unresponsive to R, and secondary dormancy was induced by high PFD (515 mol m –2 s –1 ).

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Brassinosteroid-induced de-etiolation of Arabidopsis thaliana seedlings resembles the long-term effects of cytokinins

Functional Plant Biology ◽

10.1071/pp98010 ◽

1998 ◽

Vol 25 (6) ◽

pp. 719 ◽

Cited By ~ 2

Author(s):

Jie Luo ◽

Ji-Chu Chen ◽

Yu-Ju Zhao

Keyword(s):

Arabidopsis Thaliana ◽

Term Effect ◽

Hypocotyl Elongation ◽

Long Term Effects ◽

Short Term ◽

Expression Of Genes ◽

Long Term Effect ◽

In The Wild ◽

Positive Regulators

Cytokinins can cause de-etiolation of Arabidopsis thaliana (L.) Heynh. seedlings growing in the dark. Brassinosteroids (BRs) have been considered to regulate negatively the de-etiolation in dark-grown Arabidopsis seedlings. We show here that epi-brassinolide (epi-BL) can partially produce the phenotype of de-etiolation as caused by treatment with cytokinins in the dark, including the development of leaves and epicotyls in the wild-type and the BR-deficient mutant det2. But BRs cannot inhibit hypocotyl elongation, nor restore all the inhibition caused by cytokinins and light. We have found that there are distinct short term and long term phases of induction of de-etiolation by cytokinins. The short-term effect is probably coupled to ethylene in the inhibition of the hypocotyl elongation; the long-term effect causes morphogenesis of leaves and epicotyls. BRs can only regulate de-etiolation in the long term. We propose that the inhibition of hypocotyl elongation of det2 in darkness is caused by the absence of BR-dependent elongation rather than the inhibition caused by the expression of genes for photomorphogenesis. We propose that BRs resemble cytokinins in regulating de-etiolation as positive regulators, and that the inhibition of hypocotyl elongation and the development of leaves and epicotyls in de-etiolation are independent processes.

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Evidence for the Roche Lobe Overflow in VV Cephei

Highlights of Astronomy ◽

10.1017/s1539299600006456 ◽

1986 ◽

Vol 7 ◽

pp. 211-213 ◽

Cited By ~ 1

Author(s):

E. F. Guinan ◽

G. P. McCook ◽

R. H. Koch ◽

R. J. Pfeiffer

Keyword(s):

Binary System ◽

Red Light ◽

Monitoring Program ◽

Close Binary System ◽

Roche Lobe ◽

Close Binary ◽

Intrinsic Variability ◽

Large Level ◽

Photometric Monitoring

AbstractThe VV Cep close binary system (O8V + M2 lab; P = 20 3 yrs.) is described from published spectral, radial velocity, photometric, and astrometric results. A long-term photometric monitoring program shows intrinsic variability in a red bandpass. Variability exists on several time scales and the longest of these is attributed to tidal distortion of the cool supergiant by the equally massive hot companion. A theoretical “distortion” light curve, when faced against the observations, indicated the radius of the supergiant to be significantly smaller than the accepted value of ~1600R⊙. This conclusion is examined in the context of a pulse of polarized red light occurring near the time of periastron and interpreted as Roche Lobe overflow of the supergiant envelope. It is shown that the photometric and polarimetrie results may be made accordant, not by appeal to a very large level of scattered red light, but rather by invoking the loss of constraint originally imposed by the Roche Lobe geometry.

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