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

Exercise No. 3.19 92
HYDROIZATION OF TOMATO AND CARROT
SEEDS FOR BETTER DROUGHT TOLERANCE OF
ORGANICALLY-GROWN VEGETABLES
BaCKGroUND aND raTIoNalE
124
Field Guide of Discovery-based Exercises for Organic Vegetable Production
Hardening could either be done before sowing (presowing
hardening or hydroization) or a week or two before
transplanting (seedling hardening). Pre-sowing hardening
or hydroization consists of soaking seeds in water for 1 –to
48 hours depending on seeds, and then air-drying to their
original moisture content before sowing. This is generally
practiced for vegetable seeds. For tomato and carrot, this usually takes 24 to 48 hours 93 .
Hydroization is a good cultural practice, where drought is foreseen, as it is expected to induce
drought resistance. Researchers reported that hydroization can increase yield by about 25 percent
in tomato and carrot 94 . As in stratification, very few farmers in FFSs had shared their experiences
about hydroization despite known benefits that can be derived from this practice. This exercise was
designed to allow farmers and facilitators to share their more innovative experiences in hydroization
as a strategy to improve drought tolerance of organically-grown tomato and carrot.
How long will this exercise take?
• Thirty minutes for field walks, farmer interviews, and observations of fields planted to hydroized
and non-hydroized tomato and carrot seeds; and
• Thirty minutes to one hour hands-on and brainstorming session in the processing area.
learning objectives
when is this exercise most
appropriate?
ɶ In FFS, TOT, and VST
sessions, before sowing
tomato or carrot seeds in
learning field; and
ɶ When farmers want to
learn improved pre-sowing
hardening or hydroization
techniques for tomato and
carrot seeds from other
farmers and facilitators.
• To make participants aware of and understand the hardening of some vegetable seeds by
hydroization to improve their drought tolerance; and
• To learn and do improved techniques shared by farmers and facilitators in hydroization of
tomato and carrot seeds.
92 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. pp112-114.
93 Bautista, O.K. (ed). 1994. Introduction to Tropical Horticulture. 2 nd Edition, SEAMEO Regional Center for Graduate Study and Research in Agriculture
and University of the Philippines Los Baños, College, Laguna, Philippines. pp295-296.
94 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.