HORT2007 Plant Propagation - Grafting

Flashcards on plant propagation by grafting, covering key concepts, applications, the process of graft union formation, influencing factors, and genetic limits of grafting.

Grafting

Joining of two pieces of living tissue that grow and develop as one plant.

Budding

A form of grafting that uses a small scion with usually only one bud.

Horticultural Applications of Grafting

Used for ornamental combinations, precocity, dwarfing, productivity, fruit quality, and root/shoot pest/pathogen resistance.

Scientific Applications of Grafting

Used for regeneration biology, vasculature, callus, studying mRNA, mobile siRNA components, miRNA, hormones, and Cas9-guides.

Reasons for Grafting

Difficulties of propagating many woody species by seed or cuttings, maintaining clones, and changing cultivars.

Steps in Graft Union Formation

Lining up vascular cambiums, wounding response, callus bridge formation, wound repair, and new vascular tissue production.

Factors Influencing Graft Success

Temperature, moisture, polarity, workmanship, viruses, insects, and diseases.

Incompatibility in Grafting

Grafts between distantly related plants have a low percentage of successful unions.

External Symptoms of Graft Incompatibility

Failure to form a union, yellow foliage, decline in vegetative growth, shoot dieback, and premature death.

Anatomical Flaws Leading to Incompatibility

Callus formation with irregular cell walls and parenchyma tissue interrupting xylem.

Phytohormones

Auxins and cytokinins

Grafting Techniques

Saddle, bark, cleft, chip, bud, wedge, hole insertion, splice, approach, vegetables, tube, woody species, micro-grafting, whip and tongue, embryo, scion, side-veneer, inflorescence, rootstock, butt-end.