A seed is the embryo of a new plant. Every seed contains stored food—carbohydrates, proteins, fats and minerals—to nourish the embryonic plant inside.
Each seed also has a protective shell and a way of being dispersed. In fact, seeds are so well organized that they are like highly equipped fortresses with special supplies of food against long sieges.
Simple Forms
Seeds are a remarkable part of the plant world. They come in many shapes and sizes, are often covered by a protective shell or hull, and contain reserve food materials for the embryo plant. Seeds also play a key role in spreading plants to new regions and can be important sources of medicinal and industrial products.
A mature seed is a resting embryo plant, with one or more cotyledons (in flowering plants), and a potential shoot point, called the plumule or epicotyl. It also may have an endosperm.
The seeds of most flowering plants have two cotyledons, while those of gymnosperms have several. This basic difference has led to different classifications of seeds and helps distinguish two major groups of plant families. Cecilia Zumajo, a graduate student at the Garden’s Pfizer Plant Research Laboratory, is studying genes that are involved in seed development and how they have evolved. Her work is helping to clarify some of the complex mechanisms that control ovule and seed development.
Smooth Surfaces
A laser range-scanner is used in product design, reverse engineering and rapid prototyping to quickly acquire geometric surface data of parts and models. This data is often in the form of a dense and noisy surface mesh that must be simplified into a set of piecewise-smooth surfaces that can be manipulated for their desired shape characteristics. This paper presents a method that automates this process.
A variety of micro and nanostructures in the surface of plant cuticles influence the physical or optical behavior of multifunctional interfaces between plants and their environment, such as wettability1. Surface wetting is characterized by the contact angle (CA) of a water droplet on a surface: surfaces with low CA are hydrophilic, those with high CA are hydrophobic, and those with extremely high CA are super-hydrophilic.
The spatial architecture of the mucilage envelope of seed from various Allium taxa was visualized using CPD+SEM. These mucilages contained short and long fibrils arranged in a net-like spatial structure but displayed differences in their chemical composition and structure, such as the presence of branched polysaccharides and hemicelluloses including homogalacturonan, rhamnogalacturonan I and xyloglucan [21, 22]. This can impact the wetting properties of these seeds.
Surface Characters
Seed shape varies widely among plant species and may be an important taxonomic character in certain genera. Measures of shape, such as J index (compare the area of a seed with the area of a model ellipse) or seed perimeter, can be useful in the differentiation between closely related genotypes.
Moreover, the surface characteristics of seeds also have a profound influence on wetting behavior of water droplets during imbibition and the rate of water uptake by seeds in particular. SEM examinations of the epidermal surfaces of seeds, achenes or nutlets have revealed a variety of papillose, reticulate, ribbed and rugulate patterns that can be used in conjunction with other macro-morphological features for identification.
In the present study, we surveyed seed coat micro-structures of several species of the genus Ricotia and found that they could be classified into three categories based on the sculpture of the outer seed surface and anatomy of the inner testa cell wall. These micro-morphological characters, which are not easily influenced by environmental conditions, can be useful in the systematic delimitation of species.
Surface Colors
A seed is an embryonic plant enclosed in a protective covering. It is the means by which angiosperms disseminate offspring, and it is one of the major elements in nearly all ecosystems.
Seed color is a key characteristic that can be used to identify different genotypes, which are important for understanding seed adaptation. Distinctive seed colors can be used to classify seed types and hybrids, particular pesticide applications, and even seed brands.
The morphological features used in seed identification tend to be left to individual interpretation, but standardized descriptions can effectively communicate these characteristics to a larger audience. The use of distinct seed color aids in the classification and differentiation of seed types, as well as the avoidance of potentially disastrous abuse. Seeds can be coated with a variety of ingredients to aid in handling, protection, germination, and plant establishment. Nutrients, insecticides, and rhizobia are often mixed into the coating solution. These unique seeds need to be clearly distinguished from untreated seed.
