Apple Tree Growth, Net Photosynthesis, Dark Respiration, and Specific Leaf Weight as Affected by Continuous and Intermittent Shade1

Hybrid geraniums (Pelargonium × hortorum Bailey) cv. Sooner Red were grown at temperatures ranging from 10–32°C and at various quantum flux densities. The time to visible bud stage (<0.5 cm diameter) was negatively correlated to quantum flux density at a given temperature. The time required from visible bud to flower stage was negatively correlated with temperature while light had no effect. Leaf thickness, number of palisade layers, and specific leaf weight were negatively correlated with temperature, and specific leaf weight was positively correlated with quantum flux density at a given temperature. Net photosynthetic rate ranged from 5–38 mg CO2 dm-2hr-1 for temperatures of 10-37° and was optimum at 20-32°. The Q10 of respiration for hybrid geranium leaves was about 2.2.

Section: Resultssupporting

confidence: 72%

The Effect of Temperature and Quantum Flux Density on the Morphology, Physiology, and Flowering of Hybrid Geraniums1

Armitage

Carlson

Flore

1981

“…This may reflect the relatively greater exposure of leaves to effects of precipitation. The minor or secondary importance of the solar radiation variable (relative to leaf number) is potentially similar to that reported for apple trees (2,3). However, this does not necessarily imply the absence of importance for solar radiation, since daily amounts in the geographical locations involved gen erally may be well in excess of critical levels.…”

Section: Resultssupporting

confidence: 57%

Relationship of Daily Growth and Development of Peach Leaves and Fruit to Environmental Factors

Haun

Coston

1983

A procedure was developed for detecting daily changes in the rate of growth and development of leaves and fruit of peach [Prunus persica (L.) Batsch.]. Quantitative morphological stages of leaf and fruit development were determined for 3 cultivars, transformed into growth rates, and used as dependent variables for regression on a variety of daily environmental variables: maximum and minimum temperature, degree hours, precipitation, solar radiation, estimated soil moisture (Thornthwaite method), 1- to 3-day lags of these variables, quadratic and cubic transformations, and selected 2-variable products of the basic variables. Prediction equations performed well in tests from different years, locations, and cultivars. Maximum and minimum temperature, precipitation, soil moisture, and age were the most important variables for the leaf growth prediction equation. In the fruit growth prediction equation, maximum and minimum temperature, soil moisture, and age were most important.

“…The environmental inputs were daily solar radiation values in langley per day, and maximum and minimum temperatures. The physiological parameters for the model were determined from a set of potted 'Jonamac' trees grown at Geneva, N.Y., and from the literature (1,2,11,14). An increase in the leaf area was modeled as a linear function of accumulated growing degree-days, with a base of 4°C (7).…”

Section: Methodsmentioning

confidence: 99%

“…These processes, in turn, are affected by various environmental inputs, the most important of which are light and temperature. Light has a significant effect on the photosynthesis rate within the normal range of growth conditions (1,14), but little or no direct effect on the respiration rate and growth rates, whereas temperature is relatively more important to respiration (2,11) and growth rates (6) than to photosynthesis rates (ignoring extreme temperatures) (14). Therefore, shoots growing under different climatic conditions would be expected to show differences in C import and export.…”

mentioning

confidence: 99%

Carbon Balance Model of a Growing Apple Shoot: II. Simulated Effects of Light and Temperature on Long and Short Shoots

Johnson

Lakso

1986

A computer model of a growing apple (Malus domestica Borkh.) shoot was used to estimate the effects of light and temperature on the C balance of a shoot. Long-term average solar radiation (langley/day) and maximum and minimum temperatures from Geneva, N.Y., were used as weather inputs. To simulate other weather conditions, solar radiation was increased or decreased by 150 langley/day, and maximum and minimum temperatures increased or decreased by 5.6°C. Both a short shoot of 2 cm and a long shoot of 50 cm final length were simulated. The model output indicated that increased light reduced carbohydrate import and caused earlier and greater export. Increased temperature increased carbohydrate import and the subsequent rate of carbohydrate export. The short shoot had a greater initial rate of C export and continued to export more total carbohydrates than the long shoot for about 30 to 50 days after budbreak. Slow leaf area development at a given temperature had little effect on carbohydrate import but delayed the beginning of export.