Flowering

Question 1

Transition at the shoot apex from a juvenile to
adult phase is controlled by a genetically
controlled

Answer 1

“developmental program”

Question 2

•Transition is induced by certain environmental cues what are they?

Answer 2

temperature and photoperiod

Question 3

define Photoperiod

Answer 3

numbers of hours of light during a 24 h D-N cycle that plant receives

Question 4

____ (photoperiod) —-> _______ (messengers)—-> _______ (flowering)

Answer 4

signal, transduction, and response

Question 5

who discovered photoperiod

Answer 5

• Garner & Allard (USDA scientists)

Question 6

when was photoperiod discovered

Answer 6

1920s

Question 7

what crop was photoperiod discovered with

Answer 7

tobacco

Question 8

the photoperiodic behavior of flowering depends actually upon the length of the _____ period

Answer 8

dark

Question 9

By this concept, a short-day plant should actually be considered as

Answer 9

long night plant

Question 10

The relative length of light vs dark period is not the determining factor in photoperiodism but the actual uninterrupted length of the _____ period is critical

Answer 10

dark

Question 11

short day plants:

Answer 11

initiate flowers when the light period

is shorter than critical day-length

Question 12

long day plants:

Answer 12

initiate flowers when the light period is longer

than critical day-length

Question 13

Day neutral:

Answer 13

Plants initiate flowers at any day-length

Question 14

what onion is not well suited for Minnesota due to bulbing response to photoperiod

Answer 14

Bermuda photoperiod= ~12 hrs

Question 15

what onion is better suited for Minnesota

Answer 15

Sweet Spanish photoperiod is more than 15 hrs

Question 16

what are reasons photoperiod is important in nature

Answer 16

Over-wintering plants stop growing, set buds and become dormant in the fall (to develop cold hardiness), and Plants within a population flower uniformly for pollination

Question 17

define “Latitudinal Ecotypes

Answer 17

Populations of plants within a
species are able to (genetically)
adapt to latitude

Question 18

‘critical’ day length is longer for plants collected at more _______ latitudes

Answer 18

Northerly

Question 19

Non-obligate short-day plant

Answer 19

Plants initiate flowers under any day-length, but will produce more flowers or flower more quickly under short days