Ecophysiology-Yield
Production Process
Crop production is a process and the tuber yield is high if:
- the dry matter production per day is high
- the production takes place over an extended period (number of days)
- a large proportion of the dry matter is used for tuber growth (harvest index)
- the growing pattern of the crop is adjusted to the length of the available growing period
Photo synthesis and Production
Photo synthesis and respiration are major processes.
PHOTO SYNTHESIS
Growing pattern and available growing period
Yield is optimal when the growing pattern of the crop is adjusted to the length of the available growing period.
GROWING PATTERN-PARTITIONING ASSIMILATES
Harvest index
The ratio: total tuber production/total plant production
Dry matter content
In a given period of time a certain quantity of dry matter is produced. Dry matter content is often inversely correlated with yield: Varieties with high tuber yield often have a relative low dry matter content; Varieties with high dry matter content often have a relative low tuber yield.
YIELD AND DRY MATTER
Tuber yield estimation
At any stage of the crop, the final crop yield can be fairly well estimated, by judging:
tuber formation, condition of foliage, maturity stage of the crop and the expected time still available for production.
TUBER YIELD ESTIMATION