NAGOYA, Japan — Researchers at Nagoya University have made an exciting discovery about how flowers reproduce, which could help farmers grow more seeds and improve crops. Their study, recently published in EMBO Reports, reveals how a female flower picks just one male partner for fertilization, thanks to a special signal.
Flowering plants, or angiosperms, have both male and female parts. During reproduction, pollen from the male part lands on the female part’s stigma. This starts the growth of a pollen tube that travels down to the ovary, where it can fertilize an egg and produce seeds.
To understand this process better, the scientists used a powerful microscope technique they developed. Lead researcher Yoko Mizuta said the three-year study involved careful handling of flower samples and fine-tuning the microscope to see deep inside the flowers.
With their new technique, the team watched multiple pollen tubes grow inside a living flower for the first time. They discovered a signal from the female part that guides the pollen tubes directly to the egg, ensuring that only one pollen tube fertilizes each egg.
This one-to-one guidance is crucial because it ensures that every ovule (the part that becomes a seed) gets fertilized properly. Surprisingly, the researchers also found a “repulsion signal” that tells other pollen tubes to stay away once one pollen tube has been guided to an egg. This prevents multiple pollen tubes from crowding a single ovule, directing them to find other ovules instead.
Mizuta was fascinated by this discovery. “The cells that attract pollen are mostly special cells in the flower, but the repulsion involves different types of cells,” she said. “It’s amazing how plants have this system of attracting and repelling to make sure fertilization happens correctly.”
This study shows that plant reproduction is a complex process controlled by various signals. These precise mechanisms ensure successful fertilization and efficient seed production, especially in tough conditions.
Mizuta emphasized how important this mechanism is for plants to maximize seed production. “By controlling pollen tube behavior so precisely, plants make sure they can produce seeds even when conditions are difficult,” she explained.
This research not only helps us understand how plants reproduce but also has practical benefits. It could lead to better farming techniques that increase seed production and improve crop yields.
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