Simulation and Prediction of Plant Phenology for Five Crops Based on PhotoperiodxTemperature Interaction

This paper presents a plant phenological model based on genotypextemperaturexphotoperiodinteraction (GPTmodel). In the model, rate of development towardsa specified stage (e.g. flowering) for a given genotype is composedof three components: the genotype's maximum rate of development;any delay due to a non-optimal temperature; and any delay dueto a photoperiod response. It is assumed that development tothe specified stage is an autonomous process established bymost, if not all, genes other than the vernalization genes andthe photoperiod genes; and that this autonomous process is delayedby any activity of the photoperiod genes. Since all physiologicalprocesses are modulated by temperature, any photoperiod responseis inevitably a photoperiodxtemperature interaction. This interactionis simulated by assuming that the photoperiod gene activityoccurs only beyond a critical photoperiod (P_c) and is enlargedby temperature above a base temperature (T_bp) that allows thephotoperiod gene activity. The model is written asR=1/D_b-S_t(T-T_opt)²-S_p(T-T_bp)|P-P_c|, whereRis the expected rate of development to the specifiedstage under any combination of temperature (T) and photoperiod(P). The other model parameters are:S_p, the sensitivity to adelaying photoperiod;T_opt, the optimum temperature for developmentin the absence of the photoperiod response;S_t, the sensitivityto a non-optimum temperature; andD_b, the basic duration to thespecified stage (or intrinsic earliness), the inverse of whichis the maximum rate of development.D_bis observable only ifT=T_optandsimultaneouslyP     

全球变化下植物的碳氮关系及其环境调节研究进展——从分子到生态系统

在全球变化条件下,温度的升高和降水格局的变化,导致淡水资源更加匮乏。环境因子胁迫,如干旱和高温等,它们单独或联合的作用将导致作物大幅度减产,引发自然生态系统退化。植物的碳氮代谢及其分配相互联系、不可分割,其生物过程及外界环境调节共同决定着植物的净生产力和营养水平。该文试图从分子、组织、器官、个体和生态系统等层面上,就植物的碳氮关系及其环境调节(温度、水分和CO₂浓度等)进行综述,并提出了进一步展开相关研究应重点关注的几个方面。     

Responses of Photosynthesis and Dark Respiration to Temperature

This analysis suggests that a model of the temperature dependenceof carbon exchange by a plant can be developed based upon absolutereaction rate theory. Component temperature-dependent physiologicalprocesses necessary to describe net photosynthesis over thebiological temperature range include the light reaction, darkreaction (carboxylase CO₂ uptake, oxygenase photorespiration)and mitochondrial dark respiration. An essential assumptionof the model is the reversibility of thermal inhibition. Supportingevidence for this assumption is provided within the biologicalrange. Thermodynamic constants were found to be strongly correlatedwith the thermal environment to which they were adapted. Therewas little difference in non-photorespiration thermodynamicconstants between C₂ andC₄species within thermal habitat types.The model shows the observed shift in temperature optima withlight intensity as a natural consequence of enzyme kineticsand absolute reaction rate theory. photosynthesis, photorespiration, dark respiration, temperature response, carbon exchange, mathematical model     

Estimating the Effects of Varying Temperature on the Rate of Development of Plants

Experiments on the effects of temperature on plant developmentusually yield measurements of the times at which recognizablestages of development are reached, and a record of the varyingtemperature patterns during development. Two complementary methodsfor analyzing such data to reveal the underlying relationshipsbetween rate of development and temperature are discussed. Inboth methods it is assumed that there exists a unique relationshipbetween current rate of plant development and current temperature. In the ‘discrete-rate’ method, the rate of developmentfunction, r(T), is approximated by a set of discrete valuesr₁, r₂...r_i...r_n, each applicable over a given temperature range.The fractional state of development of a plant, S, is writtenas the sum of the products of these rates, r_i, times the fractionof total time during development that temperature was withineach range, f_i, i.e. S = r_i. Systems of such equations can besolved for the r_i, values, and this enables an assessment ofthe rate-temperature relationship without preconceived notionson the form of the plant response. This assessment can then be used as a basis for selecting asuitable interpolation function to be fitted to the data usingthe ‘rate-function’ method. Here a mathematicalform for the function r(T) is selected at the outset. The temperaturescale is divided into discrete intervals and a set of equations,similar to the above, is developed. These equations are solvedfor best values of the parameters of the r(T) function. These methods are illustrated by application to controlled-environmentdata on times from sowing to flowering in soybeans and pigeonpeas,and on rates of leaf appearance in maize. Advantages claimed for the two methods are that they providea systematic approach for relating development to plant temperatureand that they are based upon an explicit physiological hypothesis. Phenology, Zea mays, Cajanus cajan, Glycine max     

Thermal Dependence of Air Convection Requirement and Blood Gases in the Snake Coluber constrictor

In this report I discuss ventilatory and circulatory adjustmentsthat prov for increased O₂transport associated with increasedbody temperature in the snake Coluber constrictor. Also includedis the effect of temperature upon acid-base status. Minute ventilationincreases with rising body temperature but does not keep pacewith the increment in resting O₂ consumption. The decrease inair convection requirement (i.e., ventilation ÷ oxygenconsumption) causes lung pO₂ and arterial oxygen contentto falland lung pCO₂ to rise. With the rise in lung pCO₂, systemicarterial pCO₂ and H⁺; concentration increase while plasma bicarbonateconcentration does not change. The effect of temperature uponair convection requirement, arterial pCO₂, and pH are most pronouncedat body temperatures above about 27°C whereColuber behavesapproximately as an alphastat pH regulator. Despite the inverserelationship between temperature and lung pO₂, systemic arterialpO₂ is about 80 torr lower at 15°C than at 35°C. Thisdecline in arterial pO₂ as temperature falls is explained byleft shifting the oxygen dissociation curve in the presenceof aconstant right-to-left intracardiac shunt.     

Into thin air: Physiology and evolution of alpine insects

Numerous physical parameters that influence insect physiologyvary substantially with altitude, including temperature, airdensity, and oxygen partial pressure. Here, we review existingliterature and present new empirical data to better characterizethe high-altitude environment, and then consider how this environmentaffects the physiology and evolution of insects. Using weatherballoon data from fifty-three sites across the globe, we estimatea mean altitudinal temperature lapse rate of 6.0 °C/km.We also present empirically determined lapse rates for P_O2 andair density. The temperature decline with elevation may substantiallycompromise insect thermoregulation at high altitude. However,heat-transfer models predict that lower air density at elevationreduces convective heat loss of insects by to a surprisinglylarge degree. This effect combined with behavioral thermoregulationand the availability of buffered microhabitats make the netthermal consequences of high-altitude residence strongly context-specific.The decline in P_O2 with elevation may compromise insect developmentand physiology, but its effects are difficult to predict withoutsimultaneously considering temperature and air density. Flyinginsects compensate for low air densities with both short-termresponses, such as increased stroke amplitude (but not wingbeatfrequency), and with long-term developmental and/or evolutionaryincreases in wing size relative to body size. Finally, in contrastto predictions based on Bergmann's Rule, a literature surveyof thirty-six insect species suggests that those living in colder,higher altitudes do not tend to have larger body sizes.     

獐牙菜种子萌发的研究

对温度、光照、植物激素（GA₃、NAA）条件对獐牙菜（Swertia bimaculata）种子萌发的影响进行了研究。结果表明,獐牙菜种子萌发的适宜温度为15～20℃,低温贮藏可促进其萌发,而有无光照对獐牙菜种子萌发没有明显影响,GA₃处理可提高其萌发势和萌发率,而NAA处理仅提高其萌发势。研究认为：獐牙菜种子具有休眠现象;激素及低温贮藏对打破种子的休眠具有重要作用。     

The thermal response of leaf extension rate in genotypes of the C4-grassMiscanthus: an important factor in determining the potential productivity of different genotypes

Thermal responses of plant extension rate are reported for 32genotypes of the C₄ grass Miscanthus. Displacement transducerswere used to measure plant extension rate as temperatures werestepped between 20C and 5C. Leaf extension accounted for 83%of the plant extension. The Q₁₀ between 10C and 20C for thegenotypes varied from 3.0 to 4.7. The relationship between temperature(5-20 C) and plant extension rate was found to be describedadequately by fitting a third order polynomial. An estimateof the effect of differences in the thermal response of plantextension rate on the potential yield of the genotypes was calculatedfor Irish climatic conditions using a simple growth model. Potentialyield varied between 3 and 23 t ha^–1 year^–1. Thisdemonstrates the critical role which differences in leaf expansionrate can play in the selection of more productive genotypes.The significance of vapour pressure deficit on the estimatesof thermal response of plant extension rate are discussed. Key words: Leaf growth, Miscanthus, temperature, radiation-use efficiency, vapour pressure deficit, C₄ plants     

Chemical Solution of Calcium carbonate in Sea Water

Sea water must be undersaturated for chemical solution of calciumcarbonate to occur. A practical criterion for undersaturationis shown to be (Ca²⁺) (CO₃^2-) < K'_SP, where K'_SP is the apparent(stoichiometric) solubility product. The calculations used inconjunction with this rule are outlined. The factors which affectK'_SP are examined. These factors are temperature, salinity,pressure, crystal structure, mineral composition, particle size,adsorption of ions such as magnesium, chelation, and formationof ion pairs. The ion concentration product is affected by temperature,pressure, salinity, solution and precipitation of carbonates,and changes in the partial pressure of carbon dioxide. Oceanicdata that reflect the effects of many of these factors are presented.Possible effects of the degree of saturation and of turbulenceon the rate of solution of calcium carbonate are examined.     

The Effects of Temperature on Respiration in the Amphibia

The effects of temporal me on respiration in amphibians areprimarily effects on gas exchange patterns and rate of oxygenconsumption (Qo₂) in major groups of amphibians. In temperatezone amphibians except plethodontid salamanders, pulmonary oxygenuptake increases with temperature. In plethodontid salamanderscutaneous gas exchange predominates and increases at highertemperatures. Aquatic salamanders are characterized by a lowerQo₂ than temperate amphibians at all temperatures. Tropicalanurans have a Qo₂ equivalent to temperate amphibians at a tempcrarure10 C greater. The ability of amphibians to supply their tissueswith oxygen and the effects of temperature on amphibian respiratoryparameters are suggested as probable factors causing these relationships. Recent evidence for temperature independent reduction in Qo₂in fossorial amphibians and species differences in metabolicscope is discussed.     

Growth, metabolism and growth efficiency of a euphausiid crustacean Euphausia pacifica in the southern Japan Sea, as influenced by temperature

Growth (assessed from intermolt period and molt increment) andmetabolism (oxygen consumption) of the post-larva of Euphausiapacifica from the southern Japan Sea were determined at sevengraded temperatures ranging from 1 to 25°C. The intermoltperiod shortened progressively as temperature increased from1 to 20°C, but an effect of temperature on molt-to-moltgrowth increment was not seen. Oxygen consumption rates wereaccelerated by the increase in temperature up to 20°C. Beyond20°C, E.pacifica exhibited reduced oxygen consumption anddied within 1 day without molting. After removing the effectof body size, the relationships between growth rate and temperature,and between oxygen consumption rate and temperature, were established.The carbon budget was calculated as a function of temperature.Because of differential effects of temperature on growth andmetabolism, the net growth efficiency [K₂ growthx100/(growth+metabolism)]changed with temperature. The optimum temperature at which E.pacificaattained the maximum K₂ was 11.4°C, which was derived fromcalculation of cumulative carbon invested in growth and metabolismin this animal. In an alternative method, the optimum temperaturewas obtained mathematically by solving a set of differentialequations. The biological and ecological significance of theoptimum temperature which leads to the maximum K₂ is discussed.     

Multiple Sites of Gas Exchange

SYNOPSIS. For many years the general body surface has been recognizedas the primitive site of respiratory gas exchange in the animalkingdom. Even in simple animals such as the sea anemones, however,some specialization has occurred. In epifaunal species the tentacularcrown appears to be the major site of gas exchange while inone infaunal species dermal papillae are more important. Inboth, the columnar body wall remains an additional site of O₂uptake. In the polychaete annelids an evolutionary trend can be seenfrom the predominance of the general body surface over simple,metameric gills to the predominance of highly specialized andbranched anterior gills over the general body surface. n theoligochaetes reversion to the general body surface was followedin at least one species to specialization of the tail regionto form a "lung." Multiple sites clearly exist in the molluscs, but their relativeimportance is poorly known. Several sites exist in the echinoderms,the best known being the approximately equal allocation of O₂uptake between modified tube feet and respiratory trees in theholothurians. Multiple sites of gas exchange persist even inthe crustaceans, in temporal as well as spatial dimensions.Water breathers revert to cutaneous O₂ uptake following a molt,and air breathers have evolved an array of gas exchangers adaptedto their new medium. This array is so diverse that it does notprovide a single selection pressure for hemocyanin O₂ bindingproperties which, when compared broadly, remain indistinguishablefrom those of water breathers found in similar thermal regimes.     

Aerobic composting performance and simulation of mixed sludges

The objectives of this study were twofold: to determine the specific oxygen consumption rate of mixed sludges by means of a respirometry study, and to investigate the applicability of a developed model to a pilot-scale reactor containing nightsoil and brewery sludges. The results of the study revealed the specific oxygen consumption rates to be 87.7 mg O₂/kg VS-hr and 117.7 mg O₂/kg VS-hr at temperatures of 25 °C and 35 °C, respectively. Oxygen was found to be consumed at a higher rate in the reactor operated at the higher temperature. The computer simulation for temperature variations in the pilot-scale reactor showed a good relationship between the simulated and the measured temperatures. After three days operation, the highest simulated temperature was 65 °C, whereas the highest measured temperature was 60 °C. In addition, results suggest that the model can provide an accurate air supply rate to indicate economical reactor operation.     

Effects of Seasonal Variation in Radiation and Temperature on Net Assimilation and Growth Rates in an Arid Climate

The net assimilation rate (E_A), relative growth-rate (R_w), andleaf-area ratio (F_A) were measured for rape (Brassica napus),sunflower (Hetianthus annuus), and maize (Zea mays) at varioustimes of year in an arid climate, using young plants grown widelyspaced on nutrient culture. Multiple regression analysis accountedfor 90–95 per cent of the variation in E_A and R_W in termsof two climatic variables: mean temperature and radiation receipt. E_A rose linearly with radiation in all three species; increasein E_A with temperature was greatest in maize and least (notsignificant) in rape. R_Wrose with radiation and temperature,the latter being the more important variable especially in coolweather; a temperature optimum was shown at 24° C in rape.F_A rose with increase in temperature or decrease in radiation;its variation was due to change in leaf area/leaf weight ratherthan in leaf weight/plant weight. Multiple regression analyses can lead to faulty interpretationif the independent variables are correlated (as are climaticvariables in nature), but conclusions can be checked by controlled-environmentstudies in which climatic factors are not correlated. The presentconclusions are supported by such studies. The regression equations, coupled with average weather records,indicate seasonal cycles of growth parameters. E_A is maximalnear midsummer and minimal near midwinter, following the radiationcycle. Maxima and minima in R_W are about a month later, becauseR_W is affected by the temperature cycle and this lags behindthe radiation cycle. F_A is maximal in autumn and minimal inspring. E_A is highest where radiation receipts near 750 cal cm^–2day^–1 coincide with high temperatures. This combinationoccurs only in clear midsummer weather at low latitudes, andis maintained over long periods only in arid regions. The fact that E_A rose linearly with radiation suggests thatleaf water deficits arising under high radiation had littleeffect on E_A and that saturating levels of light were very high.     

Effects of Temperature and Water Loss on Terrestrial Locomotor Performance in Land Crabs: Integrating Laboratory and Field Studies

SYNOPSIS. Terrestrial and semi-terrestrial crustaceans are exposedto fluctuations in ambient temperature and conditions that favorevaporative water loss. These environmental stresses alter performancelimits in the laboratory and behavior in the field. The maximalrate of oxygen consumption, maximum aerobic speed, and endurancecapacity are greater at a body temperature (T_b) of 24°Cthan at 15°C or 30°C in the ghost crab, Ocypode quadrata.The total metabolic cost to move at the same relative speedis greater at a T_b of 24°C than at 15°C. Slower aerobickinetics at 15°C result in a smaller relative contributionof oxidative metabolism to total metabolic cost. However, therelative contributions from accelerated glycolysis are similarat both temperatures. When locomotion is intermittent, the totaldistance traveled before fatigue can be similar at Tbs of 15and 24°C but result from different movement and pause durationsat these temperatures. Performance limits of the ghost crabare negatively affected by dehydration and are sensitive torates of water loss. In the laboratory, endurance capacity ofthe fiddler crab, Uca pugilator, is greater at a T_b of 30°Cthan at 25°C. In the field, freely moving fiddler crabswith a T_b of 30°C travel at faster mean preferred speeds,as determined by motion analysis, than crabs at 25°C. Datafor land crabs support and advance general ectothermic modelsfor the effects of temperature and dehydration on locomotorperformance.     

Differential effects of deuterium oxide on the growth and morphogenesis of Trichoderma viride

Trichoderma viride can be grown in deuterium oxide (D₂O) concentrationsas high as 99.7%. Increasing concentrations of D₂O (25–90%)progressively extend the lag phase in growth, but do not greatlyaffect the linear growth rate itself. The minimum age and sizeof colony required for photoinduction of the conidiation processis also increased. In 95% D₂O, although growth rates are stillrelatively high, both photomorphogenesis and dark conidiationare completely blocked. This block does not appear to involvethe photoprocess itself, but rather post photoinductive processessuch as differentiation of conidiophores. These observations point to an alternative, or at least additional,hypothesis to the one frequently cited—that D₂O acts throughstabilizing or "temperature lowering mechanisms. (Received January 6, 1978; )     

Relationship between T-wave amplitude and oxygen pulse in guinea pigs in hyperbaric helium and hydrogen

Diving isknown to induce a change in the amplitude of the T wave(A_Tw) ofelectrocardiograms, but it is unknown whether this is linked to achange in cardiovascular performance. We analyzed A_Tw in guinea pigs at 10-60atm and 25-36°C, breathing 2%O₂ in either helium (heliox;n = 10) or hydrogen (hydrox;n = 9) for 1 h at each pressure. Coretemperature and electrocardiograms were detected by using implantedradiotelemeters. O₂ consumption rate was measured by using gas chromatography. In a previous study (S. R. Kayar and E. C. Parker. J. Appl.Physiol. 82: 988-997, 1997), we analyzed theO₂ pulse, i.e., theO₂ consumption rate per heartbeat, in the same animals. By multivariate regression analysis, weidentified variables that were significant toO₂ pulse: body surface area,chamber temperature, core temperature, and pressure. In this study,inclusion of A_Tw made asignificantly better model with fewer variables. After normalizing forchamber temperature and pressure, theO₂ pulse increased with increasing A_Tw in heliox(P = 0.001) but with decreasingA_Tw in hydrox(P < 0.001). ThusA_Tw is associated with thedifferences in O₂ pulse foranimals breathing heliox vs. hydrox.

     

温度对黄瓜幼苗光合生理弱光耐受性的影响

以不耐弱光的津研2号和较耐弱光的戴多星黄瓜(Cucumis sativus L.)为试材,在人工气候室内研究适温25 ℃/18 ℃（昼/夜）、亚适温15 ℃/9 ℃和低温9 ℃/7 ℃对弱光(75～85 μmol·m^-2·s^-1)耐受性的影响.结果表明：弱光下黄瓜叶片的SPAD、净光合速率（P_n）、气孔导度（G_s）、蒸腾速率（T_r）、水分利用效率（WUE）、实际光化学效率（Φ_PSⅡ）、光化学猝灭（q_P）等指标下降,下降程度随温度的降低而加剧,而超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性上升.逆境解除后的恢复过程中,光合和荧光参数逐渐恢复,荧光参数恢复速度快于气体交换参数.弱光下温度越低对黄瓜幼苗叶片光合机构造成的伤害越重,低温降低了叶片对弱光的耐受性.在低温、弱光处理过程中,津研2号P_n、Φ_PSⅡ、q_P等下降程度较戴多星明显,而在随后的恢复过程中其回升速度较戴多星迟缓,表明弱光下戴多星对低温的耐受性强于津研2号.     

Cardiopulmonary Gas Exchange in the Turtle: A Model Analysis

The performance of the cardiorespiratory gas exchange systemof the turtle, Pseudemys scripla, at rest and at three bodytemperatures (15, 25, 35°C), was assessed in reference totheory and experimental data. The primary processes governinggas exchange(ventilation, perfusion, diffusion) were found tobe uniformly balanced in regard to CO₂ exchange. This was nottrue for O₂ transport where, at higher body temperature, thesystemis characterized by underventilation and overperfusionin conjunction with declining O₂ saturation levels. Adjustmentsin convection of air or blood, which favor improvement in arterialO₂ saturation levels, are incompatible with stability of theCO₂stores and acid-base state. The latter were preserved acrossthe temperature range. Comparisons between bird, mammal, andturtle illustrate close similarity in the relative roles ofthe primary processes governing CO₂ exchange. This persistsin the face of wide differences inmetabolic intensity, cardiopulmonaryarchitecture and complexity, and body temperatures characterizingthe species which were compared. The close control of carbondioxide transport may reflect a fundamental adjustment to airbreathing by lungs as primitive vertebrates emerged from waterto the terrestrial domain. From a regulatory point of view thestudy emphasizes the importance of both structural and functionalcontrol of CO₂ homeostasis. It does not rule out regulatoryfeatures which may insure more effective O₂ transport; however,the latter are not evident within the context of the steadystate assumptions underlying this analysis.     

Reanalysis of Vernalization Data of Wheat and Carrot

Vernalization is an important determinant of the growth, development,and yield of biennial and perennial crops. Accurate simulationof its response to temperature is thus an important componentof successful crop systems modelling. Vernalization has a lowoptimum temperature compared to other temperature responsesof plants, and thus may be difficult to treat using expressionsthat are appropriate for other plant processes. This paper examinesthe application of a simple equation that has been used forother processes. It reads as v=V_max(T_max-T_{Tmax- Topt} ) (T_Topt)^{T_optTmax-T_opt}, where v is thedaily rate of vernalization progress at temperature T, T_optandT_maxare the optimum and maximum temperatures for vernalization,respectively, andV_max is the maximum daily rate of vernalization(the inverse of the minimum number of days required to completevernalization), which occurs at T_opt. The model was appliedto published vernalization data for wheat and carrot. The fitsto data were good (adjusted R²for wheat of 0.94, for carrot0.98), with estimatedT_opt and T_maxbeing 5.7±0.5 and 21.3±1.4°C, respectively, for wheat ‘Norin 27’ and 6.6±0.2and 14.1±0.3 °C for carrot ‘ Chantenay RedCored’. The estimated parameters, in particular the highT_maxfor wheat, were close to those reported using differentanalytical approaches. It was suggested that the function wouldbe useful for summarizing vernalization data, and that its usewould avoid the abrupt changes that are inevitable when differentlinear relationships are used for part of the overall response.It was also suggested the high T_maxshould be taken into accountwhen interpreting data obtained with wheat grown under warmconditions. Copyright 1999 Annals of Botany Company Plant, vernalization, temperature response, modelling, wheat (Triticum aestivum L.), carrot (Daucus carota L.).