Agriculture Reference
In-Depth Information
Fig. 9.9
Fruiting stem of
highbush blueberry, showing
fruit at different stages. This
can generate a long harvest
period.
is commercially sought to be small and dry (thus fungal infection and reducing
dehydration) (Gough
1994
).
Harvesting can be manual or mechanical, with the harvest times and intervals
dependent on variety, weather conditions and availability of labor. The harvest
frequency is important in relation to the balance between quality and performance,
so that harvesting every 3 to 5 days can result in a higher yield and better com-
mercial quality compared to a harvest on a daily basis (Retamales and Hancock
2012
). The fruits destined for fresh consumption must be firm, uniformly blue and
undamaged (Gough
1994
).
Future Challenges and Opportunities
One of the major future challenges is that of climate change, resulting in high-
er temperatures and moisture variability (IPCC
2001
).Leaf damage can occur in
rapidly growing blueberry plants when temperatures approach 30 °C (Moon et al.
1987
; Hancock et al.
1992
; Trehane
2004
). This may well reflect the fact that, as
shown by Trehane (
2004
) and Lobos et al. (
2012
), fully expanded leaves can have
temperatures 10-15 °C higher than the ambient one. Shading nets are proving useful
to control plant (and fruit) temperature in the field (Lobos et al.
2012
).
Temperatures ranges during fruit ripening and coloring are also critical (Gil
2000
), and the pre-harvest environmental conditions strongly affect the posthar-
vest life of the fruit (Prange and Deell
1997
; Nesmith et al.
2005
). Additionally,
increasing temperatures can affect the behavior of pollinating insects and thus the
efficiency of fertilization of the flowers (Gough
1994
) (Fig.
9.10
).
Another aspect of climate change is the predicted reduction and change in pat-
tern of rainfall per year as well as the increase in temperature. This therefore points
to the importance of developing genotypes tolerant of reduced levels of water and
efficient in its use. Further studies of water consumption patterns are needed but
