Phytochrome B links the environment to transcription

Abstract Phytochrome B (phyB) senses the difference between darkness and light, the level of irradiance, the red/far-red ratio, and temperature. Thanks to these sensory capacities, phyB perceives whether plant organs are buried in the soil, exposed to full sunlight, in the presence of nearby vegetation, and/or under risk of heat stress. In some species, phyB perceives seasonal daylength cues. phyB affects the activity of several transcriptional regulators either by direct physical interaction or indirectly by physical interaction with proteins involved in the turnover of transcriptional regulators. Typically, interaction of a protein with phyB has either negative or positive effects on the interaction of the latter with a third party, this being another protein or DNA. Thus, phyB mediates the context-dependent modulation of the transcriptome underlying changes in plant morphology, physiology, and susceptibility to biotic and abiotic stress. phyB operates as a dynamic switch that improves carbon balance, prioritizing light interception and photosynthetic capacity in open places and the projection of the shoot towards light in the soil, under shade and in warm conditions.

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Biostimulants Application: A Low Input Cropping Management Tool for Sustainable Farming of Vegetables

Biomolecules ◽

10.3390/biom11050698 ◽

2021 ◽

Vol 11 (5) ◽

pp. 698

Author(s):

Mohamad Hesam Shahrajabian ◽

Christina Chaski ◽

Nikolaos Polyzos ◽

Spyridon A. Petropoulos

Keyword(s):

Plant Growth ◽

Abiotic Stress Tolerance ◽

Growth Yield ◽

Plant Morphology ◽

Growth And Yield ◽

Management Tool ◽

Protective Effects ◽

Biotic And Abiotic Stress ◽

Positive Effects ◽

Physiological Processes

Biostimulants, are a diverse class of compounds including substances or microorganism which have positive impacts on plant growth, yield and chemical composition as well as boosting effects to biotic and abiotic stress tolerance. The major plant biostimulants are hydrolysates of plant or animal protein and other compounds that contain nitrogen, humic substances, extracts of seaweeds, biopolymers, compounds of microbial origin, phosphite, and silicon, among others. The mechanisms involved in the protective effects of biostimulants are varied depending on the compound and/or crop and mostly related with improved physiological processes and plant morphology aspects such as the enhanced root formation and elongation, increased nutrient uptake, improvement in seed germination rates and better crop establishment, increased cation exchange, decreased leaching, detoxification of heavy metals, mechanisms involved in stomatal conductance and plant transpiration or the stimulation of plant immune systems against stressors. The aim of this review was to provide an overview of the application of plant biostimulants on different crops within the framework of sustainable crop management, aiming to gather critical information regarding their positive effects on plant growth and yield, as well as on the quality of the final product. Moreover, the main limitations of such practice as well as the future prospects of biostimulants research will be presented.

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The Building Blocks of Formulas to Measure Expectation Damages; the Indifference Principle

10.1093/oso/9780199731404.003.0013 ◽

2018 ◽

Author(s):

Melvin A. Eisenberg

Keyword(s):

Market Price ◽

Building Blocks ◽

Third Party ◽

Replacement Cost ◽

Contract Price ◽

Resale Price ◽

The Difference ◽

Lost Profit

Chapter 13 concerns the building blocks of formulas to measure expectation damages: replacement cost, market price, resale price, diminished value, and lost profits. Replacement-cost damages are based on the difference between the contract price and the actual or imputed cost of a replacement transaction. Resale-price damages are based on the difference between the contract price payable by a breaching buyer and the price the seller received on resale to a third party. Diminished-value damages are based on the difference between the value of the performance that a breaching seller rendered and the value of the performance that she promised to render. Lost-profit damages are based on the difference between the price a breaching buyer agreed to pay and the seller’s variable costs.

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Contract

Introduction to English Legal History ◽

10.1093/oso/9780198812609.003.0020 ◽

2019 ◽

pp. 369-385

Author(s):

John Baker

Keyword(s):

Eighteenth Century ◽

Standard Form ◽

Contract Law ◽

Third Party ◽

History Of ◽

The Common ◽

The Difference ◽

Privity Of Contract

This chapter explores some lines of development in contract law after 1600. First there were questions flowing from the decision in Slade’s Case – the pleading formulae known as the ‘common counts’ in indebitatus assumpsit were quickly settled and the perjury problems after the disuse of wager of law were dealt with in the Statute of Frauds 1677. Attempts to rationalize consideration in the eighteenth century were unsuccessful save that it became distinct from the requirement of an intention to be bound. The chapter traces the history of privity of contract and of the various attempts to give remedies to third-party beneficiaries. It then discusses the implication of terms into contracts, the difference between conditions and warranties, exclusion clauses, and the problems occasioned by standard-form contracts.

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Wave Modeling—Missing the Peaks

Journal of Physical Oceanography ◽

10.1175/2009jpo4067.1 ◽

2009 ◽

Vol 39 (11) ◽

pp. 2757-2778 ◽

Cited By ~ 78

Author(s):

Luigi Cavaleri

Keyword(s):

Wave Model ◽

Sensitivity Study ◽

New Physics ◽

Lower Atmosphere ◽

Physical Interaction ◽

Extreme Conditions ◽

Wind Variability ◽

Nonlinear Energy Transfer ◽

The Difference ◽

Wave Models

Abstract The paper analyzes the capability of the present wave models of properly reproducing the conditions during and at the peak of severe and extreme storms. After providing evidence that this is often not the case, the reasons for it are explored. First, the physics of waves considered in wave models is analyzed. Although much improved with respect to the past, the wind accuracy is still a relevant factor at the peak of the storms. Other factors such as wind variability and air density are considered. The classical theory of wave generation by J. W. Miles’s mechanism, with subsequent modifications, is deemed not sufficiently representative of extreme conditions. The presently used formulations for nonlinear energy transfer are found to lead to too wide distributions in frequency and direction, hence reducing the input by wind. Notwithstanding some recent improvements, the white-capping formulation still depends on parameters fitted to the bulk of the data. Hence, it is not obvious how they will perform in extreme conditions when the physics is likely to be different. Albeit at different levels in different models, the advection still implies the spreading of energy, hence a spatial smoothing of the peaks. The lack of proper knowledge of the ocean currents is found to substantially affect the identification of how much energy can—in some cases—be concentrated at a given time and location. The implementation of the available theories and know-how in the present wave models are often found inconsistent from model to model. It follows that in this case, it is not possible to exchange corresponding pieces of software between two models without substantially affecting the quality of the results. After analyzing various aspects of a wave model, the paper makes some general considerations. Because wave growth is the difference between processes (input and output) involving large amounts of energy, it is very sensitive to small modifications of one or more processes. Together with the strong, but effective, tuning present in a wave model, this makes the introduction of new physics more complicated. It is suggested that for long-term improvements, operational and experimental applications need to proceed along parallel routes, with the latter looking more to the physics without the necessity of an immediately improved overall performance. In view of the forthcoming increase of computer power, a sensitivity study is suggested to identify the most critical areas in a wave model to determine where to invest for further improvements. The limits on the description of the physics of the processes when using the spectral approach, particularly in extreme conditions, are considered. For further insights and as a way to validate the present theories in these conditions, the use is suggested of numerical experiments simulating in great detail the physical interaction between the lower atmosphere and the single waves.

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Photosynthetic Activity of Leaves of Pinus radiata and Nothofagus fusca After 1 Year of Growth at Elevated CO2

Functional Plant Biology ◽

10.1071/pp9960623 ◽

1996 ◽

Vol 23 (5) ◽

pp. 623 ◽

Cited By ~ 17

Author(s):

KP Hogan ◽

D Whitehead ◽

J Kallarackal ◽

JG Buwalda ◽

J Meekings ◽

...

Keyword(s):

Partial Pressure ◽

Pinus Radiata ◽

Photosynthetic Activity ◽

Photosynthetic Capacity ◽

Radiata Pine ◽

Rubisco Activity ◽

Co2 Partial Pressure ◽

Partial Pressures ◽

The Difference ◽

Triose Phosphate Utilisation

Radiata pine (Pinus radiata D.Don) and red beech (Nothofagus fusca (Hook. f.) Oerst.) were grown for over 1 year at elevated (ELEV, 64 Pa) and ambient (AMB, 38 Pa) CO2 partial pressure in open-top chambers. Springtime measurements of overwintering leaves showed that light- and CO2-saturated photosynthetic rates (Amax) of pine leaves were similar for the two treatments (AMB: 6.7 � 1.08 μmol m-2 s-1, mean � 1 s.e.; ELEV: 6.6 � 0.47) but, for beech leaves, Amax was greater for AMB plants (8.8 � 0.90 μmol m-2 s-1) than for ELEV plants (6.10 � 0.71). Summertime measurements of leaves grown that spring showed that for pine, Amax was similar in the two CO2 treatments (AMB 14.9 μmol m-2 s-1 � 0.80; ELEV: 13.5 � 1.9) while, for beech, Amax was higher in AMB plants (21.0 � 1.1) than in ELEV plants (17.2 � 1.9), although the difference was not statistically significant. These results indicate downregulation of photosynthetic capacity of beech but not pine. Vcmax did not differ between treatments within species, suggesting that there was no acclimation of rubisco activity. Triose phosphate utilisation limitation may have contributed to the downregulation of Amax in beech. For pine, photosynthesis at treatment CO2 partial pressures was greater in ELEV plants in both spring and summer. For beech measured at treatment CO2 partial pressures, photosynthesis was greater in ELEV plants in summer, but was similar between treatments in the springtime.

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Impact Assessment of Biological Control-Based Integrated Pest Management in Rice and Maize in the Greater Mekong Subregion

Insects ◽

10.3390/insects10080226 ◽

2019 ◽

Vol 10 (8) ◽

pp. 226 ◽

Cited By ~ 5

Author(s):

Dirk Babendreier ◽

Min Wan ◽

Rui Tang ◽

Rui Gu ◽

Justice Tambo ◽

...

Keyword(s):

Biological Control ◽

Integrated Pest Management ◽

Pest Management ◽

Smallholder Farmers ◽

Biological Control Agent ◽

Control Agent ◽

Target Area ◽

Positive Effects ◽

The Difference ◽

The Impact

The impact and sustainability of two interventions that have been formulated to introduce integrated pest management (IPM) into rice and maize crops in Southwestern China, Laos, and Myanmar between 2011 and 2016, and were assessed at the end of 2017. From 22 Trichogramma rearing facilities established during the interventions, 11 were still producing substantial quantities of biocontrol agents 1.5 years after project support had ended, while seven had stopped operations completely, and four were doing stock rearing only. Through the implementation of biological control-based IPM, slightly higher yields were achieved in maize and rice (4–10%), when compared to control farmers, but the difference was not statistically significant. However, the use of pesticides nearly halved when farmers started using Trichogramma egg-cards as a biological control agent. Support from either public or private institutions was found to be important for ensuring the sustainability of Trichogramma rearing facilities. Many of the suggested IPM measures were not adopted by smallholder farmers, indicating that the positive impacts of the interventions mostly resulted from the application of Trichogramma biological control agents. The following assessment suggests that further promotion of IPM adoption among farmers is needed to upscale the already positive effects of interventions that facilitate reductions in synthetic pesticide use, and the effects on sustainable agricultural production of rice and maize in the target area more generally.

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Post-Anthesis Photosynthetic Properties Provide Insights into Yield Potential of Tartary Buckwheat Cultivars

Agronomy ◽

10.3390/agronomy9030149 ◽

2019 ◽

Vol 9 (3) ◽

pp. 149 ◽

Cited By ~ 1

Author(s):

Dabing Xiang ◽

Chengrui Ma ◽

Yue Song ◽

Qi Wu ◽

Xiaoyong Wu ◽

...

Keyword(s):

Dry Matter ◽

Photosynthetic Capacity ◽

Positive Impact ◽

Tartary Buckwheat ◽

Yield Potential ◽

Growth Stages ◽

Photosynthetic Parameters ◽

Dry Matter Accumulation ◽

Fagopyrum Tataricum ◽

The Difference

Photosynthesis is the basis for plant productivity, and improvement of photosynthetic efficiency is an important way to improve crop yield. However, the relationship between photosynthetic parameters and the yield of Tartary buckwheat (Fagopyrum tataricum) under rainfed conditions is unclear. A two-year field trial was conducted during 2016 and 2017 to assess the photosynthetic capacity of different leaves, dry matter accumulation, and yield of four Tartary buckwheat cultivars from flowering to maturity. The leaves of all cultivars aged gradually after flowering, and the leaf chlorophyll (Chl) and soluble protein (SP) contents, net photosynthetic rates (Pn), transpiration rates (Tr), and stomatal conductance (Gs) tended to decline. The Chl, SP, Pn, Tr, and Gs of cultivars (cvs.) XiQiao2 and QianKu3 were significantly higher than those of LiuKu3 and JiuJiang at each sampling time from 18 days after anthesis to maturity, but the intercellular CO2 content (Ci) showed the opposite trend. Cultivars XiQiao2 and QianKu3 produced more total dry matter (mean 17.1% higher), had higher harvest index (HI, mean 16.4% higher), and yield (mean 29.0% higher) than cvs. LiuKu3 and JiuJiang at maturity, and the difference was remarkably consistent. The yield of all the cultivars was positively correlated with leaf Chl, SP, Pn, Tr, and Gs, but negatively correlated with Ci. At late growth stages, the high-yielding cultivars maintained higher Chl, SP contents, Pn, Tr, and Gs, and showed higher dry matter accumulation and lower Ci than the low-yielding cultivars, consistent with their higher leaf photosynthetic capacity. The important factors determining the yield of Tartary buckwheat were maintaining higher leaf Chl and SP content and photosynthetic capacity and delaying aging during the grain formation stage. Enhanced rates of photosynthesis and dry matter accumulation led to higher post-anthesis accumulation of biomass with a positive impact on grain number and higher yield.

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The half-life of the cytochrome bf complex in leaves of pea plants after transfer from moderately-high growth light to low light

Functional Plant Biology ◽

10.1071/fp16222 ◽

2017 ◽

Vol 44 (3) ◽

pp. 351 ◽

Cited By ~ 4

Author(s):

Hui Zhu ◽

Ling-Da Zeng ◽

Xiao-Ping Yi ◽

Chang-Lian Peng ◽

Wang-Feng Zhang ◽

...

Keyword(s):

Half Life ◽

Time Course ◽

Photosynthetic Capacity ◽

High Growth ◽

Limiting Factor ◽

Low Light ◽

High Photosynthetic Capacity ◽

Growth Irradiance ◽

The Difference ◽

Time Courses

The content of cytochrome (cyt) bf complex is the main rate-limiting factor that determines light- and CO2-saturated photosynthetic capacity. A study of the half-life of the cyt f content in leaves was conducted whereby Pisum sativum L. plants, grown in moderately high light (HL), were transferred to low light (LL). The cyt f content in fully-expanded leaves decreased steadily over the 2 weeks after the HL-to-LL transfer, whereas control leaves in HL retained their high contents. The difference between the time courses of HL-to-LL plants and control HL plants represents the time course of loss of cyt f content, with a half-life of 1.7 days, which is >3-fold shorter than that reported for tobacco leaves at constant growth irradiance using an RNA interference approach (Hojka et al. 2014). After transfer to LL (16 h photoperiod), pea plants were re-exposed to HL for 0, 1.5 h or 5 h during the otherwise LL photoperiod, but the cyt f content of fully-expanded leaves declined practically at the same rate regardless of whether HL was re-introduced for 0, 1.5 h or 5 h during each 16 h LL photoperiod. It appears that fully-expanded leaves, having matured under HL, were unable to increase their cyt f content when re-introduced to HL. These findings are relevant to any attempts to maintain a high photosynthetic capacity when the growth irradiance is temporarily decreased by shading or overcast weather.

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Anatomical and diffusional determinants inside leaves explain the difference in photosynthetic capacity between Cypripedium and Paphiopedilum, Orchidaceae

Photosynthesis Research ◽

10.1007/s11120-017-0466-8 ◽

2017 ◽

Vol 136 (3) ◽

pp. 315-328 ◽

Cited By ~ 5

Author(s):

Zhong-Hui Yang ◽

Wei Huang ◽

Qiu-Yun Yang ◽

Wei Chang ◽

Shi-Bao Zhang

Keyword(s):

Photosynthetic Capacity ◽

The Difference

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Effects of conifer release with glyphosate on summer forage abundance for deer in Maine

Canadian Journal of Forest Research ◽

10.1139/x98-144 ◽

1998 ◽

Vol 28 (10) ◽

pp. 1574-1578 ◽

Cited By ~ 4

Author(s):

J K Vreeland ◽

F A Servello ◽

B Griffith

Keyword(s):

Deciduous Trees ◽

Percent Cover ◽

Large Herbivores ◽

Positive Effects ◽

Habitat Value ◽

Treatment Interaction ◽

Deciduous Shrubs ◽

Northern Forests ◽

The Difference ◽

Trees And Shrubs

Effects of conifer release with glyphosate on summer forage availability for large herbivores in northern forests have received relatively little study. We determined effects of glyphosate treatment of clearcuts on abundance of summer foods for white-tailed deer (Odocoileus virginianus) at 1 and 7-10 years posttreatment. We measured the abundance (percent cover in a 0- to 1.8-m height stratum) of five forage classes for deer (leaves of deciduous trees, leaves of deciduous shrubs, forbs, grasses, ferns) on 12 clearcuts (six treated, six untreated) to determine 1-year effects and on 10 clearcuts (five treated, five untreated) to determine 7- to 10-year effects. Abundance of leaves of deciduous trees was greater on untreated sites (38 versus 11%) at 1 year posttreatment, but the difference was less (18 versus 12%) at 7-10 years posttreatment (age × treatment interaction, P = 0.005). Leaves of deciduous shrubs exhibited a similar pattern. Abundance of forbs was similar (13-14%) at 1 year posttreatment but greater on treated sites (29 versus 15%) at 7-10 years posttreatment (P = 0.03). Grasses and ferns were less abundant than other forage classes. Overall, glyphosate application initially decreased the abundance of leaves of deciduous trees and shrubs used as food in summer, but the longer term positive effects on forb abundance may result in little net change in overall habitat value.

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