Rainfed rice - IRRI books - International Rice Research Institute

Varietal Development:
Evaluation and Screening
Procedures
I
ndia has made tremendous progress in agriculture by developing highyielding
varieties (HYVs) of rice.
It is estimated that farmers in India
grow 80,000 local varieties of rice
with a yield potential below 1 t/ha.
From local landraces, about 500
improved varieties have been
developed through pure-line
selection with improved yield
potential of 1-2 t/ha.
India has released 512 HYVs so far,
with yields of 4-14 t/ha.
Evaluation process
After crosses are made, it takes seven to
eight years to stabilise them through
selection. Then, the field evaluation
process starts. Rigorous testing during
variety development ensures selection of
the right type of cultivars. The new
selections become entries for further
evaluation and must have
characteristics that last long and a
defined level of adaptability to different Semi-dwarf variety
production conditions.
Evaluation and screening involve testing
newly developed cultivars for:
yield potential vis-à-vis the best
existing varieties, used as checks;
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Do you know that?
developing a new variety of rice requires a lot of
research and even more patience.
It takes seven to eight generations to stabilise the
cultivar through breeding: four years for early/
medium varieties (two crops/year) and eight years
for late varieties (one crop/year)
A national testing program takes two to four years
The total time frame for release = six to 12 years