Plant Growth and Temperature Effects

Effects of Air Temperature on Crop Growth

• Air temperature significantly influences leaf production, expansion, and flowering.
• Growth and development of crops are primarily affected by air temperature.
• High temperatures can enhance gas and liquid diffusion rates, while solubility of substances varies with temperature.

Soil Temperature and Crop Health

• Governs absorption of water and nutrients essential for photosynthesis.
• Optimal soil microbial activity occurs between 18-30°C.
• Soil temperature impacts seed germination and root development.
• Affects biochemical reactions and the weathering of minerals.

Atmospheric Pressure and Plant Growth

• Atmospheric pressure influences respiration and gas transport in plants.
• At higher altitudes, low concentrations of oxygen and carbon dioxide lead to stunted growth.
• Increased UV radiation at high altitudes negatively affects plant health.
• Plants with robust roots and stems can withstand high winds and low pressure.

Role of Wind in Agriculture

• Wind aids in heat transport between latitudes and provides moisture critical for precipitation.
• Moderate turbulence enhances carbon dioxide consumption during photosynthesis.
• Wind activity can prevent frost formation by disrupting temperature inversions.

Importance of Rainfall

• Water is vital for crop life processes including gas exchange.
• High heat capacity and thermal stability of water help regulate crop temperature.
• Water's superior heat conduction allows efficient distribution of heat throughout plant tissues.
• Higher viscosity of water protects crops against mechanical disturbances.

Elementary Crop Growth Models

• Defined as schematic representations to mimic and understand crop systems.
• Serve as primary representations of agricultural concepts.

Potential Crop Production

• Defined as the maximum yield of a cultivar in optimal environments, free of limiting factors.
• Distinction between potential crop production (under ideal conditions) and potential yield (theoretical maximum).
• Yield potential improvements observed through conventional breeding, particularly in small grain cereals and maize.
• Genetic diversity in cultivars aids in yield potential improvements.

Achievable Crop Production

• Defined as yields constrained by water, nutrients, pests, diseases, and pollutants.
• Predictions about crop yields consider historical climate relationships.
• Unfavorable future climates may decrease crops' achievable yields.

Crop Production and Soil Water Balance

• Plant sensitivity to moisture stress varies by growth stage; young seedlings can tolerate drought, while mature crops become sensitive.
• Key stages of water stress impact cereal grain yield include floral initiation, anthesis, and grain-filling stages.
• Inflorescence development can be severely hampered by even slight water stress.

Structure of Crop Weather Calendars

• Includes climatic normals for rainfall, temperatures, humidity, and wind for optimal crop growth.
• Phenological observations are linked to climatic normals to predict high yield potential.

Remote Sensing in Agriculture

• Space-based remote sensing enhances coverage of inaccessible areas, providing essential agricultural data for management.
• Polar orbiting satellites are crucial for remote sensing applications; examples include LANDSAT and IRS.
• Geostationary satellites support telecommunication and weather forecasting.
• Remote sensing facilitates efficient resource management and timely responses to agricultural challenges.

This quiz explores the critical impact of air and soil temperatures on plant growth, development, and flowering. It covers topics such as the influence of temperature on leaf production, gas diffusion, solubility of substances, and essential soil temperature for nutrient uptake and seed germination.