1 / 16

Plant Tuberous Structures: Propagation Methods and Techniques

Learn about the specialized structures such as tubers, rhizomes, and pseudobulbs for planting propagation. Discover how to utilize tubers, roots, and shoots for the propagation of various plants like Irish potatoes and orchids. This text covers conventional and micropropagation methods with detailed illustrations.

emmahall
Download Presentation

Plant Tuberous Structures: Propagation Methods and Techniques

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. “Other” specialized structures • tubers • tuberous roots • rhizomes • pseudobulbs

  2. Propagation of “Irish” potato (Solanum tuberosum) tubers • conventional method: tuber is cut into sections, with an “eye” or node included; tubers used for propagation are called “seed” potatoes • micropropagation: veg. buds are excised, grown, multiplied in culture, handled to produce “microtubers” for virus-indexed “seed” stock • potato tubers are modified stems

  3. Fig. 15-15 and 15-16. Propagation of “Irish” potatoes by tuber pieces.

  4. Propagation by tuberous roots • Sweet potato (Ipomoea batatas) • adventitious shoots develop on the fleshy root • new “slips” are covered with soil, develop adventitious roots • Dahlia • plants are dug in the fall, divided • ea. divided section contains a tuberous root and a piece of the crown with a shoot bud

  5. Fig. 15-18. Propagation of sweetpotato by adventitious shoots from tuberous roots.

  6. Fig. 15-19. Propagation of dahlia by tuberous roots.

  7. Figure of dahlia tuberous root division, showing the “right” way and the “wrong” way (Free 1957)

  8. Rhizomes • Defn: specialized stem with the main axis of the plant growing horizontally at or below the ground surface • Types • Pachymorph: a short, thick, fleshy clump, determinate (terminating in a flowering shoot), e.g., German iris • Leptomorph: a slender stem with long internodes, indeterminate (growing continuously from the terminal apex); e.g., lily-of-the-valley)

  9. Fig. 15-20 and 15-22. Photo and figure showing pachymorph and leptomorph rhizomes

  10. Division of rhizomes • pachymorphs – rhizome sections are cut off, transplanted • leptomorphs - lateral offshoots (1st or 2nd yr) or pips (3rd-yr shoots) removed and transplanted • culm cuttings - culm (aerial flowering shoot) is laid horizontally, branches arise at the nodes (e.g., bamboo)

  11. Pseudobulbs • Defn: specialized storage structure of epiphytic orchids • Propagation methods • offshoots develop at the nodes of a long, jointed pseudobulb (e.g., Dendrobium) • rhizome division (Cattleya), cut back from the terminal end to include 4-5 pseudobulbs in each section • micropropagation

  12. Fig. 15-24. Cattleya orchid rhizome with several attached pseudobulbs.

  13. Micropropagation of orchids • disinfestation and plating of a shoot tip • formation of a “protocorm” • multiple shoots develop from protocorms • shoots are separated, rooted, transplanted to soil

  14. Fig. 18-11 and figure from Bhojwani (1983). Steps in the micropropagation of orchids.

  15. Recap • Tubers and tuberous roots • Rhizomes - types and propagation methods • Pseudobulbs and protocorms - propagation methods for orchids • And, from the text (Ch. 15): Who discovered that orchids could be vegetatively propagated by protocorms?

More Related