Aesexual Plant Propagation

Question 1

what is plant propogation

Answer 1

the arts and science of the production of more plant

Question 2

what are the 2 types of plant propagation

Answer 2

sexual -seed

asexual - vegetative

Question 3

what is fundamental differences between sexual propagation

Answer 3

• sexual exchange of genetic info

- asexual - cloning- no exchange of genetic info

Question 4

examples of asexual propagation

Answer 4

1. divison
2. cuttings
3. grafting
4. tissue culture

Question 5

what is production of seeds and example of

Answer 5

sexual reproduction - exchange genetic material

between 2 parents

Question 6

t or f ; ornamental plant come true from seeds

Answer 6

false; use asexual propagation to get exact clones

Question 7

t or f any seed harvested from a cultivar will not produce seedlings identical to the parent- genetic variation

Answer 7

true

Question 8

what is seed grown selection termed as

Answer 8

• seed grown selection is ‘ strain’= not genetically identical

Question 9

what are 5 reasons to use vegetative propagation?

Answer 9

1. poor seed production
2. poor seed viability
3. no seed available- sterile plant
4. only 1 specimen available
5. clone- preserve genetic info

Question 10

what are 3 parts of plant can take cuttings from ?

Answer 10

1. leaf
2. root
3. stems - herbaceous, softwood, hardwood

Question 11

when do you take softwood cuttings? when do you take hardwood cuttings?

Answer 11

• softwood- late spring to early summer

- hardwood- late fall- late inter

Question 12

what are stock plants/ mother , what should they have

Answer 12

• parent plants used in asexual propagation

- good health, desirable characteristics for production of new plants

Question 13

describe division

Answer 13

• cutting or breaking up of a crown or clump of suckers into segments

Question 14

what must characteristics must a segment taken from a cutting possess?

Answer 14

• bud and roots

Question 15

describe process of cuttings

Answer 15

• removing a piece from parent and that piece the regrows the lost parts of the tissue

Question 16

t or f cuttings can be done in both woody and herbaceous plants

Answer 16

true- as long as plant will form adventitious roots

• vegetatively growing plants
• once flowering initiated hard to do

Question 17

why can you use cuttings for asexual reproduction?

Answer 17

each living plant cell contains ability to duplicate all plant parts

Question 18

describe leaf cuttings?

Answer 18

• leaf blade or leaf with a petiole to propagate new plants
• trim 1/4 of leaf, dip into rooting hormone, insert rooting medium
• new plants from at base of leaf

Question 19

t or f; in leaf cuttings the original leaf is part of the new plant

Answer 19

false; usually discarded

Question 20

describe root cuttings

when should it be done

Answer 20

• take cutting of roots on angle

- during dormant season when roots have largest CHO supplies

Question 21

describe stem cuttings

Answer 21

• injured xylem and phloem cells plug tubes so fluids preserved

Question 22

what is formed when taken a stem cutting

Answer 22

• callus formed, cells nearby form adventitious roots

Question 23

what are herbaceous cutting?

Answer 23

• taken from non woody plants (perennials, houseplants)

Question 24

what are softwood cuttings

Answer 24

• pieces of new growth taken from woody stock plants

- must be taken from new growth before starts to harden into woody

Question 25

what are hardwood cuttings

Answer 25

- taken from tissue which has become woody- usually dormant

Question 26

t or f; stem cuttings are most commonly used method to produce herbaceous plants asexually

Answer 26

true

Question 27

what conditions should be applied for effective cuttings

Answer 27

- healthy plants - bottom heat - warm and moist

Question 28

what is the most common rooting hormones used commercially

Answer 28

- IBA = synthetic IAA (auxin hormone)

Question 29

what cutting would you want to use the lowest --> highest strength of rooting hormone?

Answer 29

lowest softwood- herbaceous med is semi hardwood highest- hardwood

Question 30

what is also used in addition to rooting hormone? why?

Answer 30

- fungicide ; counters damp conditions

Question 31

when are softwood cuttings taken?

Answer 31

- first year branches- not woody | - best late spring early summer after rain

Question 32

why should you make diagonal cut?

Answer 32

- increase surface area for roots to develop

Question 33

what is the best indicator softwood is ready to cut?

Answer 33

- softwood snaps when bent

Question 34

when is best time to take hardwood cuttings?

Answer 34

- late fall after a killing frost late winter

Question 35

describe grafting

Answer 35

- involves joining of different segments of 2 different plants - scion is joined to an understock - cambium layers of 2 different segments are aligned and growth together

Question 36

why use grafting techniques?

Answer 36

1. affect mature height of plant - dwarfing rootstocks 2. affect hardiness of plant - ex hybrid tea roses 3. produce plant that will not grow adventitious roots 4. produce plant in an ' unnatural form' or shape ex weeping

Question 37

true or false, grafting work for all plants

Answer 37

false; only gymnosperms and perennial dicots

Question 38

why does grafting only work for gymnosperms and perennial dicots

Answer 38

monocots dont have cambium layer --> need secondary growth

Question 39

what are 3 types of grafting?

Answer 39

1. cleft 2. budding/ chipping 3. whip grafting

Question 40

what is the scion

Answer 40

- upper part of plant - ornamental or fruiting characteristics - plant with features the grower wants

Question 41

what is the understock?

Answer 41

- roots and stem - hardiness - size potential - upright for weeping branches

Question 42

when is grafting usually done?

Answer 42

spring - collect several weeks before grafting is to occur | -scion wood collected in winter when dormant

Question 43

what wood should be selected for grafting

Answer 43

- grew previous year | - have leaf NOT flower buds

Question 44

what is critical to ensure successful grafting

Answer 44

- cambium layers on scion precisely matches understock

Question 45

describe cleft graft

Answer 45

- simplest way to graft | - scion cut into vertical to match understock wedge

Question 46

what tools can be used for grafting

Answer 46

budding knife | budding tape

Question 47

what is t/ shield budding?

Answer 47

- take bud from scion and graft to understock material | - slit understock, place bud in and tape back over

Question 48

what is chip budding?

Answer 48

bud is cut out with a chip of the underlying wood | -chip needs to be same size as the stock piece in order for cambia to align

Question 49

what is tissue culture propagation?

Answer 49

groups of plant cells are manipulated so they can produce a new plant

Question 50

what are advantages of tissue culture?

Answer 50

- fast - efficient - disease- free plants

Question 51

problems with tissue culture propagation

Answer 51

- increased risk of spontaneous mutations occur - sterile conditions bust be maintained- exact temp, light, humidity and atmosphere controlled with electronic sensors and computerized controls --> COSTLY

Question 52

describe stages in tissues

Answer 52

stage 1: start with specimen ; growth tip excised , sterilized -exposed to tube with nutrients and low auxin to cytokinin ratio stage 2: shoots multiply , cut again at set intervals -# increase until desired amount met ** both 1 and 2 done in climate controlled room stage 3: expose to high auxin low cytokinin ratio --> shoots start to produce roots as opposed to more shoots stage 4: plants put in soil