Breeding and Seed Production of Ornamental Crops (2+1)

Exercise - 4

Aim: Methods of emasculation and pollination
Objective: To learn how to make controlled crosses between any two parents
Materials required: Notched scissors, forceps, camel’s hair brush, ladder, labels, magnifying lens, crochet thread, glass rod, butter paper bags, eye lash brush, muslin cloth bags.
Emasculation:
Select appropriate shoots/ flowers on all the sides of a plant where emasculation is to be done. Remove already opened flowers or immature flower buds and leaves. In self-pollinating or in cleistogamous crops, do emasculation 3-4 days prior to day of anthesis. Do all the emasculation work in morning hours. Hold the shoot gently avoiding breakage, and in one attempt remove petals, distal ends of sepals in addition to stamens. Do this using either fingernails, forceps or modified scissors with notches cut in the blades and a screw for adjusting the degree of closure. Check if any anther has fallen into calyx cup during emasculation, if so, remove it. Cover the emasculated flowers with insect-proof bags until pollination to avoid contamination.
Pollination:
Apply fresh or stored pollen from a desired male parent on to receptive stigmas of emasculated flowers using camel’s hair brush/sterilized glass rod/cotton plug. Judge the stigma receptivity by confirming the exudation of watery fluids from stigmatic surface as seen by naked eye or through a magnifying lens. Do not overload the stigma with pollen. To avoid this, use an eye lash brush (single eye lash picks up 5-6 pollen grains). After pollination, replace the bags to protect from winds/rain. Repollinate the next day, if need be.
Bagging:
Cover the recently pollinated flowers with proper insect-proof butter paper bags. Remove the bags after the ovary starts swelling.
Labelling:
Tie a suitable label on each shoot below the last pollinated flower. Put the following information on the respective labels:

• Parentage (female x male)
• Number of flowers emasculated and pollinated
• Date of emasculation and pollination
• Name of the breeder and location

Precautions:

1. Do all the emasculation work in morning hours.
2. Do not overload the stigma with pollen.
3. Properly label the cross mentioning the parents as female × male and date of emasculation and pollination.