The effect of temperature on growth and dry matter production of avocado plants

1982 ◽  
Vol 33 (3) ◽  
pp. 549 ◽  
Author(s):  
E Lahav ◽  
T Trochoulias
Keyword(s):  
High Temperatures ◽  
Dry Matter ◽  
Extreme Temperature ◽  
Optimal Growth ◽  
Effect Of Temperature ◽  
Temperature Extremes ◽  
Dry Matter Accumulation ◽  
Temperature Conditions ◽  
Diffusive Resistance ◽  
Hass Avocado

Grafted cv. Fuerte and cv. Hass avocado plants were grown for 81 days in sunlit growth chambers at day/night temperatures of 17/10, 21/14, 25/18, 29/22, 33/26 and 37/30�C. Stem diameter, length of side branches, the number of leaves, leaf area and plant height, were all greater in the 21/14 to 33/26�C temperature range, than at temperatures of 17/10�C and especially 37/30�C, which restricted growth in both cultivars. Total dry matter accumulation by Fuerte was greatest at 25/18�C, while Hass was less affected by temperature extremes. High temperatures produced maximum dry matter in the leaves, while low temperatures produced it in the roots. Temperatures of 37/30�C reduced root growth and dry matter accumulation by 60-70% as compared with the optimal treatments. It is suggested that under high temperature conditions measures should be taken to cool the soil. The Fuerte plants were more affected by temperature extremes than were the Hass plants which had a broader range of optimal growth response. Therefore cv. Hass could be expected to adapt better to extreme temperature conditions. Hass plants grown under high temperatures exhibited a greater leaf diffusive resistance than Fuerte and are therefore more capable of reducing water loss from the leaves. As temperatures decreased, more red pigment was evident in the young flush of both cultivars.

EFFECT OF TEMPERATURE, NITROGEN FERTILIZATION AND MOISTURE STRESS ON GROWTH, ASSIMILATE DISTRIBUTION AND MOISTURE USE BY MANITOU SPRING WHEAT

1979 ◽  
Vol 59 (3) ◽  
pp. 603-626 ◽  
Author(s):  
C. A. CAMPBELL ◽  
H. R. DAVIDSON
Keyword(s):  
Spring Wheat ◽  
Leaf Blade ◽  
Dry Matter ◽  
Average Rate ◽  
Moisture Stress ◽  
Effect Of Temperature ◽  
Dry Matter Accumulation ◽  
N Accumulation ◽  
Early Stress ◽  
Dough Stage

The effects of early moisture stress [tillering (Tg) to last leaf visible (LLV)], late moisture stress [LLV to anthesis (AN)], and three rates of N fertilizer (44, 88 and 132 kg N/ha) on the development and moisture use characteristics of spring wheat (Triticum aestivum L. ’Manitou’) were determined under simulated irrigation in the growth chamber at day/night temperatures of 27 °C/12 °C (T27/12) and 22 °C/12 °C (T22/12). Plant height was unaffected by N and by early stress, but was reduced by late stress. Number of tillers increased until LLV, then decreased sharply and remained constant to maturity. More tillers were initiated at T27/12 than at T22/12, but by maturity there was little difference. Leaf blade photosynthetic area reached its maximum at LLV, while the non-leaf blade photosynthetic area reached its maximum at AN and constituted 75% of the total photosynthetic area at the milk dough stage. Heads comprised no more than 9% of the photosynthetic area at any time. Total plant matter accumulated sigmoidally, but at T27/12 and low N rates, plants lost total dry weight after the milk dough stage. Dry matter of the vegetative plant parts increased until the milk dough stage, then stems in particular, and roots to a lesser extent, lost weight. Head weight increased linearly at about 17.5 mg/head/day. Dry matter accumulation was directly proportional to N applied, inversely related to temperature, temporarily retarded by early stress and markedly reduced by late stress. Although stems were the dominant vegetative dry matter sink, leaves were the dominant N sink. A combination of high temperature, high N and moisture stress resulted in a temporary loss of N from the plants between LLV and the milk dough stage. As maturation proceeded, N assimilates appeared to move from leaves to roots into stems and thence into heads. The average rate of N accumulation in the heads was 0.22 and 0.27 mg/head/day at T22/12 and T27/12, respectively. Some N was lost by denitrification. The amount and rate of evapotranspiration were directly proportional to N applied and in general inversely related to moisture stress. The rate of moisture use was generally more rapid at T27/12, but the amount used was no different from that at T22/12. Plants stressed early recovered and used water at the same rate as unstressed plants, but plants stressed late did not recover.

scholarly journals The Interactive Effects of Daytime High Temperature and Humidity on Growth and Endogenous Hormone Concentration of Tomato Seedlings

HortScience ◽  
2020 ◽  
Vol 55 (10) ◽  
pp. 1575-1583
Author(s):  
Yanjiao Zheng ◽  
Zaiqiang Yang ◽  
Chao Xu ◽  
Lin Wang ◽  
Haijing Huang ◽  
...  
Keyword(s):  
High Temperature ◽  
Relative Humidity ◽  
Dry Matter ◽  
Soluble Sugar ◽  
Dry Matter Accumulation ◽  
Tomato Seedling ◽  
Tomato Plants ◽  
Temperature Conditions ◽  
Temperature Environment ◽  
Tomato Growth

High temperature and high relative humidity (RH) are one of the most serious agricultural meteorological disasters that limit the production capacity of agricultural facilities. However, little information is available on the precise interaction between these factors on tomato growth. The objectives of this study were to determine the effect of high temperature under different RH levels on tomato growth and endogenous hormones and to determine the optimal RH for tomato seedling growth under high temperature environment. Two high temperature (38/18 °C, 41/18 °C) and three relative humidity (50 ± 5%, 70 ± 5%, 90 ± 5%) orthogonal experiments were conducted, with 28/18 °C, 50 ± 5% (CK) as control. The results showed that the dry matter accumulation of tomato plants under high temperature environment was significantly lower than that of CK. At 38 °C, the dry matter accumulation with 70% relative humidity was not significantly different from that of CK; at 41 °C, dry matter accumulation with 70% and 90% relative air humidity was significantly greater than that of 50%. The concentrations of soluble sugar and free amino acids in all organs in high temperature-treated plants were significantly higher than that in CK. As relative humidity increased, soluble sugar concentrations of each organ decreased, and the free amino acid concentrations increased. Cytokinin (ZT) and indole acetic acid (IAA) concentrations in tomato buds were significantly lower than in CK under high temperature conditions. The lower the RH, the lower the content of ZT and IAA. The gibberellin (GA3) and abscisic acid (ABA) concentrations were higher than in CK under high temperatures. GA3 concentrations decreased and ABA concentrations were augmented with increased humidity. The differences of tomato seedling growth indices and apical bud endogenous hormone concentrations between RHs under high temperature conditions were significant. Raising RH to 70% or higher under high temperature conditions could be beneficial to the growth of tomato plants. The results contribute to a better understanding of the interactions between microclimate parameters inside a Venlo-type glass greenhouse environment, in a specific climate condition, and their effects on the growth of tomato.

Effect of temperature on seed development in jojoba (Simmondsia chinensis (Link) Schneider). I. Dry matter changes

1984 ◽  
Vol 35 (5) ◽  
pp. 685 ◽  
Author(s):  
IF Wardlaw ◽  
RL Dunstone
Keyword(s):  
Seed Development ◽  
Seed Weight ◽  
Dry Matter ◽  
Growth Period ◽  
Dry Weight ◽  
Effect Of Temperature ◽  
Dry Matter Accumulation ◽  
Size At Maturity ◽  
Optimum Temperature ◽  
Subtropical Species

Growth of the capsule and seed of jojoba were followed from pollination to maturity at eight temperature regimens ranging from 15/10 to 36/31�C (8/16 h; photoperiod 16 h). There was an initial lag before the onset of rapid (linear) seed development, during which the capsule expanded, and this lag varied from 106 days at 15/10�C to 7 days at 36/31�C. The wax concentration in the seed was low during the initial stages of development, but reached a maximum when the seeds were 70-75% of their final dry weight. The maximum rate of dry matter accumulation in the seed increased with temperature up to 33/28�C but, because of the longer growth period at low temperature, seed size at maturity was greatest at 18/13�C. The current work suggests that prolonged periods with temperatures above 36/31�C, or below 15/10�C would be harmful to the development of jojoba seed. The high optimum temperature for growth rate of the seed (33/28�C) and sensitivity to a temperature of 15/10�C, puts jojoba into the same group as many subtropical species. However, the lower optimum temperature for seed weight at maturity (18/13�C) is close to that observed for the temperate cereals.

Dry matter accumulation in potato clones under seasonal high temperature conditions in Pakistan

1992 ◽  
Vol 69 (10) ◽  
pp. 667-676 ◽  
Author(s):  
Nasrullah J. Malik ◽  
Robert B. Dwelle ◽  
Michael K. Thornton ◽  
Joseph J. Pavek
Keyword(s):  
High Temperature ◽  
Dry Matter ◽  
Dry Matter Accumulation ◽  
Temperature Conditions

Temperature effect on carbon partitioning in two commercial cultivars of sugarcane

2010 ◽  
Vol 37 (4) ◽  
pp. 334 ◽  
Author(s):  
Christopher P. L. Grof ◽  
James A. Campbell ◽  
Olena Kravchuk ◽  
Christopher J. Lambrides ◽  
Peter L. Albertson
Keyword(s):  
Dry Matter ◽  
Thermal Time ◽  
Effect Of Temperature ◽  
Dry Matter Accumulation ◽  
Degree Days ◽  
Node Number ◽  
Temperature Regimes ◽  
Commercial Cultivars ◽  
Exponential Trend ◽  
Linear Manner

The effect of temperature upon plant growth and partitioning of dry matter in sugarcane (Saccharum spp.) was determined. Sugarcane plants of two commercial cultivars, Q117 and Q138 were grown under constant conditions for 72 days then subjected to one of four different ambient temperature regimes, 14, 18, 22 or 26°C. Plants were harvested before the imposition of the treatments, then at 85, 120, 155 and 190 days after planting (DAP) for biomass and sugar partitioning. Following the imposition of temperature treatments, the increase in stalk length and node number was linear and notably different between the temperature regimes for both cultivars. When the data was described in terms of thermal time (growth temperature (°C) × number of days), the number of internodes produced per unit of thermal time was the same irrespective of the temperature in which the plants were grown and internode number increased in a linear manner with an increase in total thermal input. Stalk dry matter accumulation over time was linear at the log-scale and highly significant, (P < 0.001) for both Q117 and Q138. The linear rate of accumulation increased with temperature ranging from 1.39 g day–1 at 14°C to 5.31 g day–1 at 26°C for Q117, whereas in Q138 it ranged from 2.24 g day–1 to 4.39 g day–1 at temperatures of 14 and 26°C, respectively. The pattern of total sucrose accumulation also followed an exponential trend, with little difference evident until 155 DAP where rates increased with temperature for both varieties. However, the increase between 14 and 26°C was more profound for Q117. The sucrose/hexose ratio also differed between the cultivars. This difference was most pronounced in plants grown at both 14 and 18°C where the ratio of sucrose/hexose in Q117 was double that measured in Q138. The production of phytomeric units in sugarcane is clearly a function of accumulated degree-days and influenced by cultivar. The elongation of internodes is influenced by temperature and varietal interaction but is not a function of degree-days.

scholarly journals Gallium-Nitride Field Effect Transistors in Extreme Temperature Conditions

2021 ◽  
Vol 18 (4) ◽  
pp. 168-176
Author(s):  
Martijn S. Duraij ◽  
Yudi Xiao ◽  
Gabriel Zsurzsan ◽  
Zhe Zhang
Keyword(s):  
Gallium Nitride ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Extreme Temperature ◽  
Effect Of Temperature ◽  
Power Electronic ◽  
Electronic Circuits ◽  
Dynamic Operation ◽  
Temperature Conditions ◽  
Power Electronic Circuits

Abstract Compact power electronic circuits and higher operating temperatures of switching devices call for an analysis and verification on the impact of the parasitic components in these devices. The found drift mechanisms in a gallium-nitride field effect transistors (GaN-FET) are studied by literature and related to measurement results. The measurements in extreme temperature conditions are far beyond the manufacturer-recommended operating range. Influences to parasitic elements in both static and dynamic operation of the GaN-FETs are investigated and related toward device losses in switch-mode power electronic circuits with the example of a half-bridge circuit. In this article, static operation investigation on the effect of temperature toward resistance, leakage currents, and reverse conduction is conducted. Dynamic operation between the two states of GaN-FET is also addressed and related to the potential impact in a switching circuit losses. A thermal chamber was built to precisely measure the effect of temperature toward parasitic elements in the devices using a curve tracer. It was found that the increment in RDSon, IDSS, IGSS, and VSD can be justified by the literature and verified by measurements. Incremental COSS and decreasing VGSth was found when exposing devices to extreme temperatures. These two parameters give real challenge over designing circuits at high temperature where timing is critical. Albeit temperature challenges, it is found that investigated GaN-FETs have potential to be used in extreme temperature-operating conditions.

Responses to Brief Periods of Elevated Temperature in Ears and Grains of Wheat

1983 ◽  
Vol 10 (6) ◽  
pp. 549 ◽  
Author(s):  
SS Bhullar ◽  
CF Jenner
Keyword(s):  
Elevated Temperature ◽  
Dry Matter ◽  
Soluble Sugars ◽  
Grain Filling ◽  
Grain Weight ◽  
Effect Of Temperature ◽  
Dry Matter Accumulation ◽  
Grain Number ◽  
Final Weight ◽  
Low Humidity

Brief warming of wheat ears reduced total grain weight, due mainly to a reduction in individual grain weight but also to a small reduction (2.6-12.8%) in grain number. Warming of ears reduced the water content of the grain, independently of humidity of the air with which the ears were warmed. Warming ears at high humidity accelerated the rate of dry matter accumulation as compared to warming at low humidity but both treatments resulted in a reduction of final weight per grain. The effect of temperature, and interaction with humidity, on grain dry matter accumulation are not due to changes in the water or osmotic potential of the grain. Warming the ears reduced temporarily the amount of sucrose and other soluble sugars in the grain, but not in the rachis or the floral organs. It seems unlikely that the supply of sugars available for distribution to the grain is depressed by elevated temperature, nor were reduced rates of grain- filling at elevated temperature simpiy related to apparent concentrations of sucrose within the grain: ripening and senescence of the pericarp were hastened by warming the ears, and these responses were not accompanied by reductions in the levels of sugars in the grain.

scholarly journals Primary and Activated Sludge Biogas Production: Effect of Temperature

2018 ◽  
Vol 66 (1) ◽  
pp. 23-28 ◽  
Author(s):  
Tereza Dokulilová ◽  
Tomáš Vítěz ◽  
Jan Chovanec ◽  
Robert Rouš ◽  
Monika Vítězová ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Activated Sludge ◽  
Dry Matter ◽  
Biogas Production ◽  
Treatment Plant ◽  
Matter Content ◽  
Effect Of Temperature ◽  
Dry Matter Content ◽  
Temperature Conditions ◽  
Activated Sewage Sludge

Sewage sludge management is a problem of growing importance. Anaerobic sewage sludge stabilization is commonly used technology, where organic matter contained in primary and activated sewage sludge is converted into biogas, so both, pollution control and energy recovery can be achieved. The paper deals with the effect of process temperature (36 °C, 42 °C and 50 °C) on biogas production and quality during anaerobic stabilization of primary and activated sewage sludge generated during purifying process in low‑loaded activated sludge process. Primary and activated sewage sludge samples were taken at the wastewater treatment plant Brno, Czech Republic. The characteristics of sludges (dry matter and organic dry matter content, pH, conductivity, redox potential) were dermined. Biogas production and quality was measured using 3 anaerobic systems, each of 8 batch anaerobic fermenters, at the 3 different temperature conditions 36 °C, 42 °C and 50 °C. Hydraulic retention time was 20 days. Hypothesis, which predicts that the fermentation of primary and activated sludge provides dissimilar methane quantity and quality under different temperature conditions (36 °C, 42 °C and 50 °C), was partially confirmed. Temperature 42 °C significantly increased biogas production from primary sewage sludge (by 60 % in comparison with production at 36 °C). For activated sewage sludge samples no significant influence of temperature on the biogas production was observed.

Dealing with hot rocky environments: Critical thermal maxima and locomotor performance in Leptodactylus lithonaetes (Anura: Leptodactylidae)

2019 ◽  
pp. 155-161 ◽  
Author(s):  
Ivan Beltran
Keyword(s):  
Environmental Temperature ◽  
Extreme Temperature ◽  
Effect Of Temperature ◽  
Maximum Speed ◽  
Locomotor Performance ◽  
Extreme Temperatures ◽  
Physiological Limits ◽  
Fitness Consequences ◽  
Thermal Maximum ◽  
Environmental Temperatures

Environmental temperature has fitness consequences on ectotherm development, ecology and behaviour. Amphibians are especially vulnerable because thermoregulation often trades with appropriate water balance. Although substantial research has evaluated the effect of temperature in amphibian locomotion and physiological limits, there is little information about amphibians living under extreme temperature conditions. Leptodactylus lithonaetes is a frog allegedly specialised to forage and breed on dark granitic outcrops and associated puddles, which reach environmental temperatures well above 40 ˚C. Adults can select thermally favourable microhabitats during the day while tadpoles are constrained to rock puddles and associated temperature fluctuations; we thus established microhabitat temperatures and tested whether the critical thermal maximum (CTmax) of L. lithonaetes is higher in tadpoles compared to adults. In addition, we evaluated the effect of water temperature on locomotor performance of tadpoles. Contrary to our expectations, puddle temperatures were comparable and even lower than those temperatures measured in the microhabitats used by adults in the daytime. Nonetheless, the CTmax was 42.3 ˚C for tadpoles and 39.7 ˚C for adults. Regarding locomotor performance, maximum speed and maximum distance travelled by tadpoles peaked around 34 ˚C, approximately 1 ˚C below the maximum puddle temperatures registered in the puddles. In conclusion, L. lithonaetes tadpoles have a higher CTmax compared to adults, suggesting a longer exposure to extreme temperatures that lead to maintain their physiological performance at high temperatures. We suggest that these conditions are adaptations to face the strong selection forces driven by this granitic habitat.

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