Rootstock Types and Traits.Agri knowledge-

 

Rootstock Types and Traits.

Rootstock and scion are two important terms in horticulture, especially in fruit tree production. They refer to the two parts of a grafted fruit tree. The rootstock is the lower portion of the tree that is planted in the soil and develops a root system, while the scion is the upper portion of the tree that bears the fruit.

Rootstock:

Rootstock is a term used to describe the lower part of a grafted tree onto which the scion is grafted. Rootstock is selected for specific traits, such as resistance to soil-borne diseases or pests, drought tolerance, and adaptability to certain soil types or climates. It also affects the vigor and size of the tree. A rootstock that is dwarfing can produce a smaller tree, while a rootstock that is vigorous can produce a larger tree. This is important for fruit tree growers who want to produce trees of a specific size, as it can affect the ease of harvesting and maintenance of the trees.

Rootstocks are usually propagated through vegetative methods, such as cuttings or tissue culture. They are then grafted with the desired scion to create the final fruit tree. The grafting process involves cutting the rootstock and scion to fit together, binding them tightly, and allowing them to grow together.

Types of rootstocks:

There are many types of rootstocks used in fruit tree production, each with its own advantages and disadvantages. Some common types of rootstocks include:

Seedling rootstock:

 This is the rootstock produced from seeds. It is usually the most affordable rootstock option, but it is often unpredictable in terms of size, vigor, and disease resistance.

Clonal rootstock:

 This is a rootstock produced through vegetative propagation. It is often more uniform in terms of size, vigor, and disease resistance than seedling rootstocks.

Dwarfing rootstock: 

This rootstock produces a smaller tree, making it ideal for growers with limited space or for high-density plantings.

Semi-dwarfing rootstock: 

This rootstock produces a medium-sized tree, making it a good compromise between a full-sized tree and a dwarfing rootstock.

Scion:

The scion is the upper part of a grafted tree that bears the fruit. It is usually selected for its desirable fruit characteristics, such as flavor, size, and texture. It is attached to the rootstock through the grafting process.

Types of scions:

There are many types of scions used in fruit tree production, each with its own advantages and disadvantages. Some common types of scions include:

Budwood:

 This is a scion that is taken from a healthy fruit tree and grafted onto a rootstock. It is usually selected for its desirable fruit characteristics, such as flavor, size, and texture.

Tissue culture: 

This is a method of producing scions in a laboratory setting. It is often used to produce large numbers of identical scions for commercial fruit tree production.

Cutting:

 This is a method of producing scions by taking a stem cutting from a healthy fruit tree and rooting it. It is often used for small-scale fruit tree production.

In conclusion, rootstocks and scions are two important parts of a grafted fruit tree. The rootstock is the lower portion of the tree that is planted in the soil and develops a root system, while the scion is the upper portion of the tree that bears the fruit. Rootstocks and scions are selected for specific traits, such as resistance to soil-borne diseases or pests, drought tolerance, and adaptability to certain soil types or climates, as well as desirable fruit characteristics.

OR

Rootstock is a term used in horticulture and agriculture to refer to the base or lower part of a plant onto which a scion, or a piece of another plant, is grafted. The rootstock provides the root system of the plant, while the scion provides the above-ground portion, including leaves, flowers, and fruit. This technique of grafting is widely used in fruit tree production, grapevine cultivation, and other crops, as it allows growers to combine the desirable traits of different varieties and species, such as disease resistance, vigor, adaptability, and fruit quality.

One of the most popular rootstocks for fruit trees is called Malling 7, or M7 for short. M7 was developed in the early 20th century by the British horticulturist Thomas Andrew Knight, who crossbred several species of apple trees to create a vigorous, dwarfing rootstock. M7 was later improved by the Malling Research Station in Kent, England, which conducted extensive trials on different apple varieties and soil types. M7 was found to be highly adaptable, resistant to woolly apple aphid and crown rot, and compatible with many scion cultivars, such as Gala, Granny Smith, and Pink Lady. Moreover, M7 was shown to induce earlier fruiting, better fruit quality, and higher yield than other rootstocks, such as seedling, M2, and M26.

The reason why M7 is considered dwarfing is that it limits the growth of the scion by reducing the amount of energy that the roots can transfer to the shoots. M7 achieves this by producing small, fine roots that have a high surface-to-volume ratio and a high capacity for nutrient uptake. The small root system also allows the plant to be more densely planted, as it can absorb more water and nutrients per unit area than a larger tree. The dwarfing effect of M7 is beneficial for several reasons. First, it allows growers to produce more fruit per acre, as they can fit more trees in the same space. Second, it makes it easier to manage the trees, as they are shorter and more accessible for pruning, harvesting, and pest control. Third, it reduces the need for ladders, which are costly and risky for workers. Fourth, it accelerates the time to fruiting, as the plant has less vegetative growth to invest in before it starts bearing fruit. Finally, it enhances the quality of the fruit, as it is closer to the ground, protected from the wind and sun, and easier to pick at the right time.

However, there are also some drawbacks to using M7 as a rootstock. One is that it may be susceptible to fire blight, a bacterial disease that can affect the branches, leaves, and fruit of apple trees. Another is that it may not be suitable for all soil types and climatic conditions, as it prefers well-drained, fertile soils and moderate temperatures. Moreover, M7 may require more frequent irrigation and fertilization than other rootstocks, as it has a higher water and nutrient demand. Furthermore, M7 may not be as resistant to some pests and diseases as other rootstocks, such as M9 or MM111, which are also widely used in apple production. Finally, M7 may not be as long-lived as other rootstocks, as it tends to decline after 10-15 years of planting, due to root rot or other factors.

Despite these challenges, M7 remains a popular choice among apple growers, especially in regions with favorable soil and climate conditions. Other popular rootstocks for apple trees include M9, which is more dwarfing than M7 and better suited for intensive orchards, but also more prone to drought and winter injury; MM111, which is more vigorous than M7.

OR

Plant Root Stock Basics.

Rootstock refers to the lower part of a grafted plant that provides the root system and some portion of the stem, onto which an upper portion of a different plant, called the scion, is grafted. The rootstock can influence the overall growth, development, and resistance to pests and diseases of the grafted plant.

OR

Rootstock is an essential component of the grafting process in plants, particularly in fruit trees, grapevines, and other woody plants. The rootstock is the lower part of the grafted plant that provides the root system, as well as some portion of the stem. It is onto this rootstock that the upper portion of a different plant, called the scion, is grafted. This technique of grafting is commonly used in horticulture to produce plants with desirable characteristics, such as disease resistance, hardiness, and productivity.

The rootstock of a plant is crucial because it can influence the overall growth, development, and productivity of the grafted plant. For instance, some rootstocks are selected for their ability to resist certain diseases, pests, and environmental stresses, such as drought, cold, and soil salinity. This means that when a scion is grafted onto a resistant rootstock, the resulting plant will be more resistant to these challenges, leading to better yields and a longer lifespan. Additionally, some rootstocks can influence the size and vigor of the scion, resulting in smaller or larger trees, depending on the desired outcome.

There are several types of rootstocks, and each has its own characteristics and uses. The most common types of rootstocks include seedlings, clonal rootstocks, and inter-specific hybrids.

Seedling rootstocks are created by growing a seed from a particular species or variety of a plant. Seedlings are the most commonly used rootstocks, as they are readily available, easy to grow, and generally inexpensive. However, seedlings can have variable characteristics, such as resistance to disease or size, making them less predictable in their effects on the scion.

Clonal rootstocks, on the other hand, are produced through vegetative propagation, such as cuttings or tissue culture. This means that the genetic makeup of the rootstock is identical to the parent plant, which makes them highly predictable in their characteristics. Clonal rootstocks are commonly used in fruit tree orchards because they offer consistent and predictable growth patterns, disease resistance, and productivity.

Inter-specific hybrids are rootstocks that are created by crossing two different species or genera of plants. This is done to combine the desirable characteristics of each parent plant, such as disease resistance, cold hardiness, and high yields. Inter-specific hybrids are often used in grapevines, where they can combine the resistance to phylloxera, a pest that can decimate grapevines, and other desirable traits.

The selection of a rootstock for a particular plant depends on several factors, including the characteristics of the scion, the desired outcome, and the growing conditions. For example, in apple trees, the most commonly used rootstock is Malling 9, which is a dwarfing rootstock that results in smaller trees with high yields. In contrast, in grapevines, the most commonly used rootstock is 1103P, which offers resistance to phylloxera and other pests, as well as tolerance to drought and salinity.

The grafting process involves several steps, including preparing the scion and the rootstock, making a precise cut on each, and joining them together to form a union. The graft union is then secured with tape or wax, and the plant is grown under controlled conditions until the graft has taken, and the plant is established.

In conclusion, rootstock plays a critical role in the grafting process of plants, particularly in fruit trees, grapevines, and other woody plants. The selection of a rootstock depends on several factors, including the characteristics of the scion, the desired outcome, and the growing conditions. Different types of rootstocks, such as seedlings, clonal rootstocks, and inter-specific hybrids, each have their own characteristics.