Bulk Method

What is Bulk Method – Definition?

It is a method which can handle segregating generations, in which F2 and subsequent generations are harvested in bulk to grow the next generation. At the end of bulking period, individual plant selection and evaluation is carried out in the similar fashion as in the pedigree method.

Procedure for Bulk Method

Bulk method of plant breeding completes in following main steps.

Step Details
Hybridization Crossing among selected parents
F1 generation F1 seeds (minimum 20) planted. Bulk harvesting is carried out.
F2 to F6 generation F2 to F6 are planted, harvested in bulk. Number of plants should be as large as possible. Generally artificial selection is not carried out.
F7 generation Generally 30 to 50 thousand F6 seeds are space planted, selection is carried out based on phenotype and 1000 to 5000 selected ones are harvested separately.
F8 generation Individual plant progenies are grown, inferior progenies eliminated. Harvested in bulk.
F9 generation Preliminary yield trials with standard varieties as check. Selection is based on yield.
F10 to F13 generation Multi location yield trials are conducted using standard varieties as check. Evaluation of performance of lines is done.
F14 generation Seed multiplication for distribution.

Advantages, disadvantages and applications of the bulk method are listed on the page Bulk method – advantages and applications. Know them in detail.

Visit SSD – Single Seed Descent Method.