Thermal Time Requirement Thermal Time = ΣGDD Maximum Temperature (°C) Minimum Temperature (°C) Base Temperature (°C) Number...
Climate Productivity Index (CPI) CPI = Yield / ΣGDD Yield (kg/ha) Total GDD (ΣGDD) Calculate
Crop Coefficient (Kc) Calculator Kc = ETc / ETo | ETc = Kc × ETo Reference ET...
Radiation Interception (%) RI (%) = (1 − e⁻ᵏᴸᴬᴵ) × 100 Leaf Area Index (LAI) Extinction Coefficient...
Heat Use Efficiency (HUE) HUE = Yield / ΣGDD Yield (kg/ha) Total GDD (ΣGDD) Calculate
Phenothermal Index (PTI) PTI = ΣGDD / Number of Days Total GDD (ΣGDD) Number of Days Calculate
Heliothermal Units (HTU) HTU = GDD × Sunshine Hours Maximum Temperature (°C) Minimum Temperature (°C) Base Temperature...
Photothermal Units (PTU) PTU = GDD × Day Length Maximum Temperature (°C) Minimum Temperature (°C) Base Temperature...
Growing Degree Days (GDD) GDD = ((Tmax + Tmin) / 2) − Tbase Maximum Temperature (°C) Minimum...
Physiological Efficiency Index PEI = Economic Yield / Total Biomass Economic Yield (kg/ha) Total Biomass (kg/ha) Calculate
Crop Vigor Index CVI = Germination% × Seedling Length Germination (%) Seedling Length (cm) Calculate
Competitive Ability Index CAI = RY₁ / RY₂ Crop 1 Yield (Mixture) Crop 1 Yield (Pure) Crop...
Stand Density Efficiency SDE = Yield / Density Yield (e.g. kg/ha) Plant Density (plants/ha) Calculate
Canopy Architecture Index CAI = LAI × k Leaf Area Index (LAI) Extinction Coefficient (k) Calculate
Leaf Angle Distribution Index k ↔ χ (Leaf Angle Distribution) Extinction Coefficient (k) Solar Zenith Angle (θ...