Cytoplasmic and Nuclear Effects on Agronomic Traits in Diploid Interspecific Potato Hybrids

Area of Science:

• Plant genetics
• Crop science
• Genomics

Background:

• The cultivated potato (Solanum tuberosum L.) has a narrow genetic base, increasing vulnerability to stresses.
• Understanding nuclear and organelle genome contributions to traits is crucial for potato breeding.

Purpose of the Study:

• To analyze the relative content of nuclear, mitochondrial, and plastid genomes in diploid potato hybrids.
• To investigate the contribution of these genomes to agronomic traits such as pollen fertility, starch content, and chip color.

Main Methods:

• Flow cytometry for nuclear genome size (2C-value).
• Quantitative polymerase chain reaction (qPCR) and multiplex PCR for organelle DNA content and cytoplasm types.
• Kendall's correlation and Principal Component Analysis (PCA) for data analysis.

Main Results:

• Genome size was stable across cultivation conditions.
• Significant variations in organelle content and cytoplasmic types correlated with pollen fertility and starch content.
• Plastid and mitochondrial DNA content strongly influenced genotype differences, with nuclear DNA contributing independently. Cytoplasmic male sterility was noted in T-type cytoplasm genotypes.

Conclusions:

• Organelle genome composition significantly impacts potato agronomic traits.
• Nuclear-cytoplasmic interactions play a role in traits like male sterility.
• Analysis of cytoplasm and nuclear genomes offers potential for potato breeding program enhancement.