DESCRIPTION OF COURSES
SSAC 611/ AP 611 SOIL PHYSICAL ENVIRONMENT AND PLANT GROWTH (3L+1P) III
To impart knowledge on characterization and management of soil physical environment in relation to plant growth and yield.
Introduction: Effect of soil physical properties on plant growth - soil water, soil air, soil temperature, mechanical impedance and tillage practices.
Soil water: Soil moisture – plant water relations, available water, newer concepts of water availability, least limiting water range, soil-plant-atmosphere system as a physical continuum, plant uptake of soil moisture, evaporation, transpiration and evapotranspiration, dynamics of water in the soil- plant-atmosphere continuum.
Root growth – germination and seedling emergence, hydraulic properties of roots, characterization of root growth parameters, water balance of the root zone, soil physical properties and root growth, flow of water to roots.
Soil temperature – effect of soil temperature on plant growth, soil temperature management, thermal regimes, mulching, Radiation – heat budget and energy balance in the field, radiation use efficiency, radiation exchange in the field, exchange of heat and vapour to the atmosphere.
Aeration – critical oxygen concentration and factors affecting.
Field water balance: Field water balance, irrigation and water use efficiency, consumptive use, plant uptake of soil moisture.
Nutrients: Nutrient uptake and use by plants, managing soil physical condition for improved nutrient use efficiency, integrated nutrient management in relation to soil physical condition.
Resource conservation technologies: Bed planting and zero-tillage - types, suitability and effect on soil physical properties, other resource conservation technologies and the impact (short and long term ) on soil health.
Modelling: Interactions of soil, management and climatic factors on plant growth, and development of sustainability indices.
List of Practicals
Measurement of penetration resistance and LLWR; plant water potential; field saturated hydraulic conductivity; transpiration using porometer; root length density, root diameter, root weight using root scanner; germination percentage as affected by temperature; estimation of evapo-transpiration losses under different management options; measurement/estimation of consumptive water use, production functions, field water balance components, and water uptake by plants.