Theory and Practice: Agronomic Practices for sowing true seed and transplanted seedlings

Mohinder Singh Kadian

CIP-SWCA

What is TPS?

TPS is a sexually produced propagule

TPS can be open pollinated or hybrid

Hybrid TPS is produced by crossing

Hybrid TPS is better in vigor, yield and tuber uniformity etc.

Steps for hybrid true seed production

1. Planting of hybridizing block - Staggered planting of male parent - Sodium vapor lamps of 100/250 watts per 100

sq.m.

2. Hybridization- Thinning of female flower bunches- Collection of flowers and extraction of pollen grains (Buzzers and vibrators are developed for pollen

extraction)- Pollen can be stored under dry and low

temperatures

3 Pollination - Dipping stigma of female parent ( If possible select self male sterile female

parent to reduce the labour cost required for emasculation)

4. Harvesting of berries and seed extraction - Use of Juice extractor to make pulp - Treatment of pulp with 10% HCL.for 20 minutes - Fresh seeds treated with 0.05% Sodium

Hypochlorite for 10 minutes to disinfect surface fungi or bacteria

- Drying of seed in shade - Packing of seed at 4-5% moisture level

Breaking of Dormancy of true seed

--------------------------------------------------- •Treat seed with 2000 ppm GA3 for 24 hours•Wash the true seeds with water•Dry true seed under shade•Check the germination of seed before sowing in bed•Store seed in tight containers or plastic bags at cool temperature.

Agro-techniques for potato production from TPS.

Steps followed

Substrate for Nursery Beds (50% +50% subsoil or riber-bed sand)

Nursery Bed Preparation (Raised beds-6-8 “)

X

Producing TPS Seedling

TPS sowing (10cm or 25x4cm)

Shade (mulching)

Fertilizer Application(as recommended)

Producing Potatoes from Seedlings

Field preparation

Transplanting of Seedlings

Irrigation and earthing up

Dehauling and harvesting

Suitable Areas

Production of Seedling TubersBed Preparation

Fertilizer Application

TPS Sowing

Foliar spray of urea