Syllabus
- Plant sampling for leaf area and biomass estimation; analysis of growth and yield parameters – LAD, CGR, LAI, LAR, SLA portioning efficiency, HI.
- Measurement of light interception, light extinction coefficient, energy utilization efficiency based energy intercepted, and
- Gas exchange: principles and uses to assess variations in CO2 and water vapour transfer, determination of A/gs and intrinsic WUE
- Quantification of chlorophyll content by various methods: colorimetric and SPAD The concept of SLN
- Chlorophyll fluorescence and quenching coefficients
- Theoretical aspects of carbon isotope fractional and its use in determining WUE
- Quantification of RuBisCO content by ELISA (if possible)
- Determination of RuBisCO activity and activation state using radioactive CO-2
- CO2 and light response curves and computation of carboxylation efficiency, quantum efficiency, relative limitations of photosynthesis at single leaf
- Adoption of crop models: Growth and yield prediction by Duncan’s and Passioura’s models
Unit I
Theory
Block 1: Photosynthetic Processes
Canopy Architecture and Energy Utilization
Parameters associated with canopy architecture that determine radiation interception and absorption, Energy absorption by primary and accessory pigments and energy utilization efficiency, Light distribution inside the canopy and concepts of light extinction coefficient.
Unit II
Photochemical Processes
Ultrastructure of chloroplast: structure and composition of lamellar system, Components of electron transport, Water oxidation system and energy conservation processes, Pigment systems and the generation of a powerful oxidant and a powerful reductant, Chlorophyll fluorescence and fluorescence quenching: qN, qP, NPQ.
Unit III
Biochemical Processes
CO2 diffusion and resistances (gs and gm). Concept of Ci determining CO2 diffusion. RuBisCO activation state, kinetics and catalytic properties, Carboxylation processes in C3, C4 and CAM plants and their relevance, CO2 concentrating mechanisms and their importance in improving carbon assimilation, Ecological significance of C4 and CAM photosynthesis, Photorespiration and Mitochondrial respiration and net carbon gain, Carbon isotope discrimination and its importance as a surrogate of Ci.
Unit IV
Product Synthesis and Translocation
Triose phosphate utilization and regulation of Calvin cycle mechanisms, Product synthesis and partitioning between starch and sucrose, Concepts of end-product inhibition or Pi-regeneration limitation, Phloem transport and factors that regulate phloem loading and un-loading.
Unit V
Growth and Yield forming Mechanisms
Carbon gain and the concepts of Canopy photosynthesis. Relevance of LAI and LAD in determining total carbon gain and crop growth rates, Source: Sink relationship and its relevance in governing differences in crop growth rates and productivity. Concepts of HI and partitioning coefficient and remobilization of carbon from vegetative organs to reproductive structures, Growth analysis and parameters that explain growth rates: NAR, CGR, HI and their inter-dependence.
Unit VI
Block 2: Yield Improvement and Modelling
Unit I: Molecular Options to Improve Photosynthesis, Growth and Productivity
Characteristic features of the Chloroplast genome: its structure and genes associated with various photosynthetic mechanisms, coordinated expression of chloroplast and nuclear genome for maintaining photosynthetic activities. Genomic and genetic resources such as specific genes and QTL associated with photosynthetic processes Transgenic options to enhance photosynthetic performance such as transferring genes to mitigate oxidative stress damage (SOD, APX, AKR etc), Theoretical concepts of crop improvement through inducing CCM in C3 plants and reducing photorespiration.
Unit II: Fundamentals of Dynamic Simulation Models
Collection of crop specific genetic coefficient, Crop, soil and historic weather data
Unit III: Description of Well-established Yield Models
Application and limitations of modeling, Yield prediction models such as APSYM, Peanut Grow etc, Machine learning approaches and IoT for making informed on- farm decisions.
Unit IV: Examples of Robust Models Extensively Used
Duncan’s yield prediction model, Passioura’s model for growth maximising.
Aim of the course
The course provides a comprehensive theoretical and hands on experience and expertise to students on various aspects of photosynthesis including biophysical, biochemical and molecular regulations. While canopy photosynthesis drives crop growth rates, factors associated with sink activity and partitioning determine productivity. Hence, adequate emphasis would be given to canopy photosynthesis, translocation and its feedback regulation, Crop growth and yield structure analysis and their responses to environmental factors. Growth and yield prediction models and their relevance will be adequately discussed.
