Researchers unravel mystery of pollination

Research led by local scientists has unraveled the fundamental pollination mechanism of flowering plants, which may be utilized for high-quality varieties in agriculture.

The results were published in the journal Science recently after four year’s study by Dr Li Chao’s team from the School of Life Sciences at East China Normal University.

By focusing on Arabidopsis, an important model plant in the Brassicaceae family, the research revealed the molecular mechanism for pollen-stigma mutual recognition, recognizing pollen of their own species and rejecting others for reproduction.

The research shows that the key to this genetic mechanism lies in the information exchange principle of mutual recognition between pollen and stigma.

The genetic mechanism of plants, or the pistil stigma, ensures the specificity of different species, which means it receives only the pollen of the same species for germination and fertilization.

Researchers established a set of experimental systems, including the precise pollen hydration observation system and the detection system of reactive oxygen species in stigma papilla cells.

Like other international research groups in search of stigmatic receptors, they initially assumed that the mutation in the stigmatic receptor genes for pollen would result in a phenotype of reduced pollen hydration rate.

By thinking out of the box, researchers found that FER/ANJ mutants showed a phenotype of accelerated pollen hydration rate.

“This enabled us to figure out the mechanism of pollen recognition through inhibition of stigma receptor kinase signaling pathway,” said Li.

“In the end, we found that the receptor kinase senses and switches between small peptide ligands of various types, so as to accurately regulate the stigmatic recognition of pollen.”

The research indicates that this might be a conserved pollen-stigma recognition mechanism widely found in flowering plants.

The discovery is expected to help overcome distant hybridization barriers and obtain superior varieties in cross breeding.