麻豆淫院

Terrestrial plants have developed strategies to cope with suboptimal conditions. Storage of nonstructural resources is one of those strategies. Nonstructural carbohydrates (NSCs) of plants are primarily sugars and starch, and have been studied extensively to more fully understand how plants sustain productivity and recover from stress. Most plants use starch for storage and sucrose for transport of NSCs, but some species also rely on oligosaccharides for these functions

A recent study explores the carbohydrate composition in the stems of two species of cycads, revealing significant findings that deepen our understanding of these ancient plants. The research focuses on assessing the abundance and types of carbohydrates stored in the stems, contributing to knowledge on how cycads manage energy storage and resilience in their natural habitats.

The paper is in the journal HortScience.

Cycads, known for their primitive features and slow growth, are one of the oldest plant lineages still living today. The study examined two species, paying particular attention to the stems, which serve as the primary storage organ for carbohydrates. Through advanced analytical techniques, researchers quantified the types and levels of carbohydrates, including sugars and starches, in the stems of these species.

The findings indicate that these cycads possess a unique carbohydrate profile, which may play a crucial role in their survival, especially in challenging environmental conditions. By storing significant amounts of carbohydrates, cycads can maintain metabolic functions during periods of stress, such as drought or nutrient deficiency. The study's results open up new avenues for further research into the evolutionary adaptations of cycads and how these plants have managed to persist through dramatic shifts in climate and ecosystem changes over millions of years.

Quantifying the standing pool of sugars is useful for studying sugar storage components, but is not useful for determining ephemeral sugar relations. For example, stachyose was abundant in these cycad stems and each stachyose required the prior biosynthesis of galactose, but the free galactose pool was negligible. This study shows that an experimental approach that quantified the monosaccharide pool without also quantifying the oligosaccharide pool would underestimate galactose synthesis of these cycad plants.

A greater understanding of cycad NSC relations is needed to inform cycad horticulture and conservation. For example, growth of Cycas micronesica leaves and male cones generated declines in stem NSCs, revealing the deployment of these stem NSCs to support the demanding sink activity. This concept was exploited during historical starch extraction from C. revoluta stems, as harvests were timed to occur immediately before a new flush of leaf growth. Invasions of the scale Aulacaspis yasumatsui Takagi have caused irreparable harm to the international cycad horticulture trade and declines in C. revoluta NSCs correlated with duration of A. yasumatsui infestations.

The study's results open up new avenues for further research into the evolutionary adaptations of cycads and how these plants have managed to persist through dramatic shifts in climate and ecosystem changes over millions of years.