Fruit shattering character in semi-domesticated Chenopodiaceae species: case example of an Andean grain Chenopodium pallidicaule
Juan Pablo Rodriguez, PhD student
Department of Agriculture and Ecology / Crop Science, University of Copenhagen
Seed
shattering is one of the main characters in semi-domesticated cultivated
species. The fruit shattering reduces good yields compared to rice and other long
time domesticated cereal crops. Among the Chenopodiaceae species it is known
that the Andean Chenopodium quinoa Willd.
was domesticated about 7000 years ago, and in this species the achenes are
tightly compacted in an infructescence at the top of the main stem
(panicle). Worldwide quinoa is
appreciated for its high nutritional value; however, there is a close relative
species Chenopodium pallidicaule
Aellen (cañahua or cañihua), which remains as a semi-domesticated plant. This cañahua
is cultivated in the most difficult agricultural highland rural communities in Bolivia and Peru and offers highly valuable
traits as low temperature tolerance; and above all the achenes are free from saponins.
This character makes it more easy to prepare for food than the quinoa. One main
problem with cañahua is the early fruit shattering behaviour shortly after
flowering. The harvesting has to be carried out when the ripe achenes are beginning
to disperse. For the farmers this is an indication of when to start harvesting.
When this aspect is not taken into account, the loss of achenes can reach 30%. In
my trial I have started examining a local Bolivian cañahua cultivar in
Taastrup. The plants are recorded and surveyed at each developmental stage
since they were sowed in pots. A more careful study of the shattering of achenes
will be determined in the infructescence after the flowering stage. The
shattered nuts will be collected according to physiological maturity stage. And
the abscission layer at the flower-pedicel junction in the local cultivar will
be examined. A more precise estimation
of how many nuts are shattered during the growing season will provide better
knowledge finding the optimal time to harvest plants in relation to plant
development.
