Fruit-enveloping vine found by 90-year-old nature volunteer

The leaves of the plant can help create a protective micro climate in production

Paris: An unusual vine discovered by a 90-year-old volunteer nature guide in Japan has a “unique” way of using its leaves to curl around its fruits to envelop them in a protective micro climate, scientists said on Wednesday.

The cucurbitaceous vine, a type found in East Asia, is an oddity because while leaves come in all shapes and sizes and perform a crucial role in photosynthesis, they are rarely associated with reproduction.

But a new study published in the journal Proceedings of the Royal Society: Biological Sciences found that the vine had specialized leaves able to enclose fruit and enhance seed production in colder conditions.

The research was led by Nobuyuki Nagaoka, the 90-year-old guide at Yamagata Prefectural Natural Museum Park, who first spotted the leaf behavior in 2008 and has observed it every year since.

They describe the vine as a slender, annual plant that often inhabits the edges of deciduous forests with disturbances like roads, rivers or mountains.It can either be hermaphrodite or male and produces small, white flowers pollinated from August to September and later develop into fruits, each with a single seed.

The researchers looked at plants at different altitudes at the foot of Mount Gassan, in the southern part of the Dewa Mountains, in an area partly within Yamagata park.They noted some leaves on hermaphrodite plants that were undeveloped in summer “expanded and overlapped with each other” to create a sort of cocoon around immature fruit.

Previous research has described some functions of leaves that aid reproduction, such as the plant Saururus chinensis, whose leaves can temporarily turn white to attract pollinators.