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what is a weed seed bank

Variation in the characteristics of seed dormancy determine whether a species’s soil seed bank is transient (temporary) or persistent. Transient seed banks are composed of species that produce seeds with a brief or no period of dormancy. Such seeds generally germinate prior to the next round of seed production, and the seed bank is thus continually depleted and reestablished. Transient seed banks are typical for many plants, especially long-lived perennials such as trees and shrubs. Often, such species rely on other strategies or life-history stages for persistence. For example, species may depend on long-lived adults, “banks” of seedlings in a forest understory, or extensive seed dispersal. In contrast, species with persistent seed banks have seeds that can remain dormant for more than a year, meaning that there is always some viable seed in the soil as a reserve. Persistent seed banks are common in annual plants and some woody plants, in which the failure of seed to establish the next generation would mean the collapse of the population. Scientists sometimes further classify persistent seed banks based on the extent or pattern of dormancy.

In addition to dormancy, considerable variation occurs in seed bank germination because of seasonal or other environmental shifts. Disturbances such as fire, flooding, windstorms, plowing, or forest clearing are frequently strong selective forces and may increase the overall germination response of seeds. Ecosystems characterized by wildfire often have extreme cases of persistent seed banks, as is common for many areas with Mediterranean climates, such as Australia, California, and South Africa. In those ecosystems the germination of many species requires signals provided by fire, such as a heat pulse into the soil or chemicals from smoke or charred wood. Germination may not occur until after a wildfire, which then results in mass germination from the seed bank the following spring. Similarly, the seed banks of agricultural weeds are often well adapted to the almost continuous human-made disturbances of their environment. Such weeds frequently have complex dormancy patterns that reflect the agricultural practices under which they evolved.

soil seed bank, natural storage of seeds in the leaf litter, on the soil surface, or in the soil of many ecosystems, which serves as a repository for the production of subsequent generations of plants to enable their survival. The term soil seed bank can be used to describe the storage of seeds from a single species or from all the species in a particular area. Given the variety of stresses that ecosystems experience—such as cold, wildfire, drought, and disturbance—seed banks are often a crucial survival mechanism for many plants and maintain the long-term stability of ecosystems.

The role of disturbance

Seed dormancy and environmental constraints on germination influence various characteristics of soil seed banks. For example, seed dormancy determines how long a seed can remain viable in the soil. Factors such as embryo immaturity, chemical inhibitors, and physical constraints influence seed dormancy. Light filtered through plant canopies, for example, can inhibit germination in some species, while a long winter chilling may break dormancy in other species. The result is a considerable variety in the patterns of germination of the seed banks by seasons, disturbances, or other environmental shifts.

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Researcher Dan Cohen was one of the first scientists to model soil seed banks. In the 1960s, focusing on desert annuals subject to highly irregular rainfall, he developed population-dynamics models that suggested that a reserve of some fraction of seed in the soil was essential for the plants to avoid local extinction. Cohen found that the dynamics of soil seed banks reflect the degree of ecological constraint a species or population faces in establishing the next generation. Although his work focused on annuals, the conceptual framework applies readily to any plant species. Such modeling is important to ecological research and conservation planning, as traditional demographic models and field surveys often fail to consider population reserves in the soil.

A marijuana seed bank is a business which specializes in not only storing and selling cannabis seeds, but also on feminizing seeds to reduce the chance of male plants developing and maximize yields for commercial and individual growers.

Seed feminization is even more important, particularly for growers. Only female plants grow buds – male plants may have trace amounts of THC in their leaves, but they produce pollen, instead of THC-laden buds. Therefore, growers should focus primarily on growing female plants.

Maximum Yield Explains Marijuana Seed Bank

The problem is that when left to nature, seeds tend to produce a 50/50 split between male and female plants. Growers then spend time and resources growing plants, half of which must be discarded when it becomes apparent that they are male. Seed feminization reduces the percentage of male to female seeds by a significant amount.

As more and more states legalize marijuana, growers big and small find that they need to locate a reliable source of cannabis seeds. Generally, this is done through a marijuana seed bank – a company that develops cannabis strains, stores seeds, and then sells those seeds to commercial and individual growers. However, there’s more to it than that.

A marijuana seed bank is not just another grower, or a seed repository. These companies are at the forefront of seed feminization and strain development. Many seed banks have created highly-popular strains known for specific benefits or effects, such as providing greater mental clarity and focus, or for higher THC content.