Variety x line cross - A suggested breeding procedure for maize in developing countries

Area of Science:

• Agricultural Science
• Plant Breeding
• Genetics

Background:

• Phra-Phutthabat No.5 (PB5) is a widely cultivated local rice variety in Thailand.
• Global open-pollinated rice lines (S3 and S6) were sourced for cross-breeding.

Purpose of the Study:

• To evaluate the yield performance of hybrids derived from crossing PB5 with global rice lines.
• To compare the efficacy of variety x line crosses versus variety x variety crosses.
• To identify promising breeding strategies for rice improvement in developing nations.

Main Methods:

• Cross-breeding PB5 with S3 and S6 rice lines.
• Field trials conducted in Thailand, Laos, and Israel during both dry and wet seasons.
• Yield comparison of hybrids against the PB5 control variety.

Main Results:

• Several hybrids significantly outperformed the PB5 control in both dry and wet seasons.
• Variety x line crosses demonstrated superior yields compared to variety x variety crosses across all tested locations.
• Hybrids incorporating South African germplasm showed intermediate yields, while those with African and Asian germplasm yielded the lowest.

Conclusions:

• The variety x line cross breeding strategy is effective for enhancing rice yields.
• This method presents a simple and rapid approach for rice breeding programs in developing countries.
• Strategic selection of germplasm is crucial for optimizing hybrid performance.