Economic Botany - Plant Propagation

Front 1

What is heterosis

Back 1

Hybrid vigor, robustness found in offspring with high levels of heterozygosis. Often seen in hybrid seeds.

Front 2

What are heirloom varieties

Back 2

Plants that have been allowed to openly pollinate, are usually from landrace, and have strong phenotypic diversity. These plants breed true to type and have a historic association with place and people.

Front 3

What is the difference between a germplasm bank and a gene bank

Back 3

A germplasm bank contains all the alleles for a species in the form of organisms. A gene bank contains the genetic material for a species in the form of components of the organism.

Front 4

What are the tests for seed viability

Back 4

Germination- seeing if the seed grows
Tetrazolium- dye applied to opened seed, red = yes
Excised embryo- remove embryo, try to grow on media

Front 5

What are the phases of germination

Back 5

1. Imbibition of water
2. Activation of hormones & food stores
3. Embryo growth and development

Front 6

What is fragmentation

Back 6

Asexual propagation method involving removal of plant material and replant/regrow, when all the plant material is required.

Front 7

What is layering

Back 7

Asexual propagation method used for growing roots and/or shoots off of a living plant.

Front 8

What are cuttings

Back 8

Asexual propagation method using part of a plant to grow a whole new plant

Front 9

Preparation and growth of tissue culture

Back 9

1. harvest explant- small tissue sample, must be disease free*
2. media/conditions- grown on high growth stimulation media with environmental conditions
3. callus formation- auxin & cytokinin
4. grow plantlet- roots then shoots

Front 10

What are auxins

Back 10

Plant hormones created in the apical meristem, expressed higher in young plants. Generally function in cell elongation- apical dominance effect. Promote root initiation when applied to cuttings and callus formation in grafting media.

Front 11

What are gibberellins

Back 11

Plant hormones that function in regulation of stem growth, flower & fruit maturation, sex differentiation, and seed germination and utilization of food stores.

Front 12

What are cytokinins

Back 12

Plant hormones that function in cell division and shoot formation.

Front 13

What is ethylene

Back 13

Plant hormone produced at higher rates in rapidly growing and dividing cells. Has a limited water solubility, rapidly and easily diffuses between cells and out of the plant. Functions in flower sex expression, fruit ripening, preventing excessive growth, and release of fruit from the plant.

Front 14

What is abscisic acid

Back 14

Plant hormone usually produced in the leaves. Functions in regulating parts of seed development (nutrient partitioning into seed and preventing premature germination), seed and bud dormancy, and initiation of plant stress response.