Field Guide of Discovery-based Exercises for - Aseanipm ...

Section 3 • Living Soil, Integrated Soil Nutrient and Crop Managements
Exercise No. 3.22 99
VARIETAL ADAPTABILITY TO DIFFERENT ELEVATIONS
AS A kEY FACTOR FOR IMPROVING ORGANIC
VEGETABLE PRODUCTIVITY IN THE HIGHLANDS
BaCKGroUND aND raTIoNalE
Yield potential is usually a reflection of plant’s ability to use
and adapt to its environment in terms of its morphology,
anatomy, or biochemical nature. In the Cordilleras, vegetable
crops, to be more productive, must adapt to unfavorable
environmental conditions, which include presence of
harmful insects and diseases, water logging, drought, too high or too low temperature, too much or
too little light or nutrients.
Varietal adaptability of crops in highlands differs relative to elevations mainly because of temperature
as well as pest and disease prevalence. At high elevation, potato and cabbage are predominant crops
because of their tolerance to relatively cooler temperatures. Whereas, snap bean, green pea and
cucumber can tolerate slightly warmer temperature and are more adapted in middle elevation. The
beneficial parasitoid Diadegma sp. and harmful microorganism cyst nematode are more adapted to
cooler temperature. Hence, diamondback moth (DBM) is easier checked in high elevation, where its
parasitoid Diadegma sp. adapts very well, than at middle elevation. Similarly, cyst nematode does
not thrive well at warmer temperature and is never a problem of potato grown in middle elevation 100 .
Every vegetable farmer knows which crop is most adaptable to his specific environment. His
experiences, when shared with others in FFSs, will allow them to acquire additional knowledge and
understanding to improve their current practices, which may result to better crop productivity. This
exercise was designed to address this concern.
How long will this exercise take?
• Thirty minutes to one hour for field walks and observations of organic vegetable crops most
adapted in adjoining vegetable fields of learning field; and
• Thirty minutes to one hour brainstorming session in the processing area.
99 Adapted from Callo, Jr., D.P., L.B. Teofilo, and H.A. Tauli (eds). 2002. Field Guide of Discovery-based Exercises for Vegetable IPM, Volume II. SEAMEO
Regional Center for Graduate Study and Research in Agriculture (SEARCA), Los Baños, Laguna, Philippines. pp121-123.
100 Kudan, S.L. 1998. As cited in: Callo, Jr., D.P., L.B. Teofilo, and H.A. Tauli (eds). 2002. Field Guide of Discovery-based Exercises for Vegetable IPM,
Volume II. SEAMEO Regional Center for Graduate Study and Research in Agriculture (SEARCA), Los Baños, Laguna, Philippines. 366p.
133
when is this exercise most
appropriate?
ɶ In FFS, TOT, and VST
sessions, before planting
vegetable crops in
learning field; and
ɶ When farmers want to
learn more of varietal
adaptability of organic
vegetable crops in their
area from other farmers.