Fruit Types
The morphology of plant fruits varies greatly, serving as both an important organ for plant propagation and a major source of human nutrition. Understanding the classification rules of fruit types helps us better recognize plant growth and development characteristics, which has significant practical value in agricultural production and horticultural cultivation.
Characteristics and Classification System of Single Fruits
The Nutritional Storage Mystery of Flesh Fruits
Fleshy fruit groups are known for their juicy flesh and can be divided into several types based on structural differences: berries (grapes, tomatoes) have entirely fleshy fruit walls; drupes (peaches, apricots) form hard endocarps; hesperidium (citrus fruits) develop special vesicular structures; pomes (apples, pears) involve the development of the receptacle; and gourds (watermelons, pumpkins) originate from the swelling of the inferior ovary. These fruits attract animals to disperse seeds through their bright colors.
The Wisdom of Dry Fruit Survival Strategies
After maturation, the pericarp of dry fruits becomes woody. Schizocarpous fruits (legume pods, cruciferous silicles) disperse seeds by splitting open, while closed fruits (sunflower achenes, maple samaras) rely on wind or animals for dispersal. Among them, caryopses (rice, wheat) have pericarps and seed coats that completely fuse, forming a unique dispersal mechanism.
The Composite Development Model of Aggregate Fruits
Aggregate fruits, developed from multiple pistils, show special structures: star-shaped aggregate fruits in the case of star anise, numerous achenes on the surface of strawberries, honeycombed nutlets on lotus pods, and granular drupe aggregates in raspberries. These fruits often enhance reproductive efficiency by increasing the area of the receptacle.
The Group Development Wisdom of Collective Fruits
Collective fruits that develop from an entire inflorescence include: mulberries formed from enlarged female inflorescences, figs with hidden inflorescences developing into sac-shaped fruits, and pineapples, which fuse multiple ovaries to form compound fruits. These fruits increase seed production through collective development strategies and often have high sugar content to attract animals to eat them.
The morphological evolution from single fruits to compound fruits reflects the exquisite adaptation of plants to dispersal methods. Understanding the structural characteristics of different fruit types not only helps us accurately identify plant species but also provides a theoretical basis for crop improvement. Modern breeding techniques are manipulating fruit development genes to cultivate new varieties with greater commercial value.