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

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Field Guide of Discovery-based Exercises for Organic Vegetable Production
5 Calculate percentage of successful crossing by computing success rate as follows:
% Successful Crosses =
Number of pollinated fruits x 100
Total number of pollinated flower buds
5 Discuss results from variety crossing table in plenary. Compare and review targets, number
of actual crossing with rate of success.
5 Take note of all relevant observations and experiences during this activity.
5. Synthesize and summarize output of small groups into one big group output. Draw up
conclusions and recommendations from this exercise; and
6. As an additional activity, conduct participatory discussions on important concerns, particularly
on the following areas:
5 Potential characters of hybrids produced;
5 Evaluation of hybrids produced; and
5 Purity of hybrids as a function of purity of parents used.
some suggested questions for processing discussion
❏ What are the similarities and differences in plant morphology of different cucurbit crops?
❏ What are the similarities and differences in flower morphology of different cucurbit crops?
❏ Why do we need to monitor flowering stages of parent varieties?
❏ Why is emasculation not required for cucurbit crops? Why do we pollinate flowers during
hybridization of cucurbit crops?
❏ When are the best times for preparation and pollination of cucurbit flowers for successful
hybridization?
❏ What is the use of a variety crossing table? What are the reasons for low success rate of your
hybridization work?
❏ What is the purpose of bagging and tagging of pollinated cucurbit flowers?
❏ What is the most productive and cost efficient way to hybridize two varieties?
❏ How many successful crosses do we need to build a successful hybridization? How many
crosses can you manage?