Pedigree Method of Plant Breeding | Agriculture Optional Notes for UPSC PDF Download

Introduction

In the realm of crop improvement, various methods are employed to enhance the quality and performance of plant species. While mass and pureline selection prove to be efficient for certain scenarios, they fall short when dealing with segregating populations such as F2, F3, and so forth, which result from controlled crosses. To navigate this intricate landscape, plant breeders have at their disposal several techniques, and one of the most crucial among them is the Pedigree Method.

What is Pedigree Method?

The Pedigree Method is a systematic approach to plant breeding that focuses on maintaining and improving specific traits within plant populations. It involves selecting individual plants from the F2 generation and their subsequent generations, growing their progenies, and meticulously recording the parent-offspring relationships. This method is indispensable in the realm of plant breeding.

What is Pedigree Record?

A key component of the Pedigree Method is the Pedigree Record. This record keeps track of the lineage and genetic information of the selected plants, enabling breeders to make informed decisions regarding their breeding programs.

Procedure of Pedigree Method

The Pedigree Method unfolds in several generations, each with a distinct purpose and set of activities.
The following table outlines the essential steps involved in this method:

• F1 Generation: F1 plants are cultivated to ensure an adequate supply of F2 seeds, with 15-30 plants chosen for the subsequent generation. These F1 plants are planted and observed for their behavior, especially regarding easily observable traits. Any unintentional self-pollination is detected and removed.
• F2 Generation: This generation is of utmost significance, as it displays the highest genetic diversity and allows for the selection of individual plants. Approximately 150-250 plants are grown and thoroughly assessed. Plant selection is based on their observed traits. The selected plants are harvested individually, and comprehensive records are maintained.
• F3 Generation: Progeny rows of the selected F2 plants are grown alongside a control variety in the F3 generation, with a minimum of 30 plants per row. The plants are thoroughly assessed and visually compared to the control varieties. It is essential to reject progenies that exhibit susceptibility to diseases and pests. Each plant is harvested individually, and detailed records of genetic and agronomic characteristics are recorded.
• F4 Generation: The progeny of selected F3 plants are grown to produce F4 families, with each F3 plant's progeny constituting a family. The number of families can be reduced through visual selection.
• F5 Generation: In this generation, the selected plants are grown in progeny rows, typically in large numbers. By this stage, the variation within families significantly decreases, and the selected families are harvested in bulk.
• F6 Generation: Preliminary yield trials of the selected families are conducted at this stage. Screening for resistance and quality is also performed to achieve over 99% homozygosity.
• F7 Generation: The progenies are evaluated for various characteristics, including plant height, lodging resistance, disease resistance, flowering time, maturity time, and quality.
• F8-F10 Generation: The superior lines are tested in replicated yield trials at multiple locations. A line that outperforms the best commercial variety is identified for release as a new variety.

Application of Pedigree Method

The Pedigree Method finds its application in the development of improved plant varieties. By carefully selecting and breeding plants with desirable traits across multiple generations, breeders can create new varieties that exhibit enhanced characteristics, such as disease resistance, yield, and quality.

Merits

The Pedigree Method offers several advantages, including the ability to maintain and improve specific traits, adapt to the needs of the breeding program, and produce new and improved plant varieties.

Demerits

While powerful, the Pedigree Method demands meticulous record-keeping and extensive time and effort, making it a resource-intensive approach to plant breeding.

Achievements

Over the years, the Pedigree Method has played a pivotal role in the development of numerous high-performing plant varieties. Its contributions to agriculture are immeasurable, as it continues to aid in feeding the growing global population.

Conclusion

The Pedigree Method of plant breeding stands as a cornerstone in the pursuit of improving crop quality and performance. By carefully selecting and breeding plants across multiple generations, plant breeders can make substantial contributions to agriculture and address the challenges of our time. This method represents a testament to the ever-evolving science of crop improvement and its crucial role in ensuring food security and sustainable agriculture.