JoshuaRobinson

This is My Sandbox for Grafting Article

Tools

Depiction of general purpose grafting knives

• Cutting Tools: It is good procedure to keep the cutting tool sharp to minimize tissue damage and clean from dirt and other substances to avoid the spread of disease. A good knife for general grafting should have a blade and handle length of about 3 inches and 4 inches respectively. Specialized knives for grafting include bud-grafting knives, surgical knives, and pruning knives. Cleavers, chisels, and saws are utilized when the stock is too large to be cut otherwise.
• Disinfecting Tools: Treating the cutting tools with disinfectants insures the grafting site is clear of pathogens. A common sterilizing agent is absolute alcohol.
• Graft Seals: Keeps the grafting site hydrated. Good seals should be tight enough to retain moisture while, at the same time, loose enough to accommodate plant growth. Includes specialized types of clay, wax, petroleum jelly, and adhesive tape.
• Tying and Support Materials: Adds support and pressure to the grafting site to hold the stock and scion together before the tissues join, which is especially important in herbaceous grafting. The employed material is often damped before use to help protect the site from desecration. Support equipment includes strips made from various substances, twine, nails, and splints.
• Grafting Machines: Because grafting can take a lot of time and skill, grafting machines have been created. Automation is particularly popular for seedling grafting in countries such as Japan and Korea where farming land is both limited and used intensively. Certain machines can graft 800 seedlings per hour.

Factors for Successful Graft

• Compatibility of Scion and Stock: Because grafting involves the joining of vascular tissues between the scion and rootstock, plants lacking vascular tissues, such as monocots, cannot be grafted. Even between vascular plants, grafting capabilities vary greatly. As a general rule, the closer two plants are genetically, the more likely the graft union will form. Genetically identical clones and intra-species plants have a high success rate for grafting. Grafting between species of the same genus is usually successful. Grafting has a low success rate when performed with plants in the same family but in different genera. And grafting between different families is rare.

• Cambium Alignment & Pressure: The vascular cambium of the scion and stock should be tightly pressed together and oriented in the direction of normal growth. Proper alignment and pressure encourages the tissues to join quickly, allowing nutrients and water to transfer from the stockroot to the scion.

• Completed during Appropriate Stage of Plant: The grafting is completed at a time when the scion and stock are capable of producing callus and other wound-response tissues. Generally, grafting is performed when the scion is dormant, as premature budding can drain the grafting site of moisture before the grafting union is properly established. Temperature greatly affects the physiological stage of plants. If the temperature is too warm, premature budding may result. Elsewise, high temperatures can slow or halt callus formation.

• Proper Care of Graft Site: After grafting, it is important to nurse the grafted plant back to health for a period of time. Various grafting tapes and waxes are used to protect the scion and stock from excessive water lost. Furthermore, depending on the type of graft, twine or string is used to add structural support to the grafting site. Sometimes it is necessary to prune the site, as the rootstock may produce shoots that inhibit the growth of the scion.

Natural Grafting

The bark of the tree may be stripped away when the roots make physical contact with each other, exposing the vascular cambium and allowing the roots to graft together.

Additionally, grafting may protect the group from wind damages as a result of the increased mechanical stability provided by the grafting.

Natural grafting is rarely seen in herbaceous plants as those types of plants generally have short-lived roots with little to no secondary growth in the vascular cambium.

History, society and culture

Fertile Crescent

As humans began to domesticate plants and animals, horticultural techniques that could reliably propagate the desired qualities of long-lived woody plants needed to be developed. Although grafting isn't specifically mentioned in the Hebrew Bible, it is claimed that ancient Biblical text hints at the practice of grafting. For example, Leviticus 19:19, which dates to around 1400 BCE, states " [the Hebrew people] shalt not sow their field with mingled seed... "(King James Bible) Some scholars believe the phrase mingled seeds includes grafting, although this interpretation remains contentious among scholars.

By 500 BCE grafting was well established and practiced in the region as the Mishna describes grafting as a commonplace technique used to grow grapevines.

China

One of the best pieces of evidence of early Chinese grafting appears in 600 BCE from Jia Sixie's Qimin Yaoshu (Essential Skills for the Common People). In the book he refers to an even older text containing information on grafting, which would date the origin of Chinese grafting to around 2000 BCE, however this book is missing so the claim cannot be validated.

Some believe grafting in China appeared as early as 5000 BCE, though The Precious Book of Enrichment, the text often cited to support such claims, hasn't been found.

Greece and Rome, and Islamic Golden Age

In Greece, a medical record written in 424 BCE contains the first direct reference to grafting. The title of the work is On the Nature of the Child and is thought to be written by a follower of Hippocrates. The language of the author suggests that grafting appeared centuries before this period.

In Rome, Marcus Porcius wrote the oldest surviving latin text in 160 BCE. The book is called De Agri Cultura (On Farming Agriculture) and outlines several grafting methods. Other authors in the region would write about grafting in the following years, however, the publications often featured fallacious scion-stock combinations.

During the European Dark Ages, Arabic regions were experiencing an Islamic Golden Age of scientific, technological, and cultural advancement. Creating lavishly flourished gardens would be a common form of competition among Islamic leaders at the time. Because the region would receive an influx of foreign ornamentals to decorate these gardens, grafting was used much during this period.

Europe and the United States

After the fall of the Roman Empire, grafting survived in the Christian monasteries of Europe until it regained popular appeal during the Renaissance. The invention of the printing press inspired a number of authors to publish books on gardening that included information on grafting. One example, A New Orchard and Garden: Or, the Best Way for Planting, Graffing, and to Make Any Ground Good for a Rich Orchard, Particularly in the North, was written by William Lawson in 1618. While the book contains practical grafting techniques, some even still used today, it suffers from exaggerated claims of scion-stock compatibility typical of this period.

While grafting continued to grow in Europe during the eighteenth century, it was considered unnecessary in the United States as the produce from fruit trees was largely used either to make cider or feed hogs.

French Wine Pandemic

Beginning in 1864, without warning grapevines across France began to sharply decline. Thanks to the efforts of scientists such as C. V. Riley and J. E. Planchon, the culprit was identified to be phylloxera, an insect that infests the roots of vines and causes fungal infections. Initially, farmers unsuccessfully attempted to contain the pest by removing and burning affected vines. When it was discovered that phylloxera was an invasive species introduced from North America, some suggested importing rootstock from the region as the North American vines were resistant to the pest. Others, opposed to the idea, argued that American rootstocks would imbue the French grapes with an undesirable taste; they instead preferred to inject the soil with expensive pesticides. Ultimately, grafting American rootstock onto French vines became prevalent throughout the region, creating new grafting techniques and machines. American rootstocks had trouble adapting to the high soil pH value of some regions in France so the final solution to the pandemic was to hybridize the American and French variants.