PLANT PROPAGATION

Information

  • Patent Application
  • 20230329152
  • Publication Number
    20230329152
  • Date Filed
    September 16, 2021
    3 years ago
  • Date Published
    October 19, 2023
    a year ago
Abstract
Methods of propagating and growing poinsettias in pots have allowed poinsettias to become the highest selling potted flowering plant. The present application relates generally to the field of plant propagation. In particular, a method of producing a pre-pinched, callused poinsettia cutting is provided. Also provided is a method to produce a poinsettia with improved growth habit. The invention also provides a pre-pinched, callused poinsettia cutting.
Description
FIELD OF THE INVENTION

The invention relates to compositions and methods for propagation of plants, such as Poinsettias. In particular, the invention relates to methods of pre-pinching callused cuttings.


BACKGROUND

In nature, the poinsettia grows as a small tree up to twelve feet tall. Methods of propagating and growing poinsettias in pots have allowed poinsettias to become the highest selling potted flowering plant. Poinsettias are propagated by cuttings. Growers of Poinsettia (Euphorbia pulcherrima) purchase vegetative cuttings from suppliers in two different product forms: unrooted cutting (URC) or callused cutting (CC). Unrooted cuttings are harvested from stock plants of poinsettia according to size specifications and then are packaged and shipped to customers. Upon receipt of URCs, growers stick the cutting in media for rooting. Callused cuttings are harvested like URCs and then the supplier inserts the cutting into a media to initiate callusing (i.e., the first stage of adventitious rooting). After callus formation, the cuttings are removed from the media, washed, packaged, and shipped to customers. Upon receipt of CCs, growers stick the cutting in media and rooting speed is faster than with URCs. Following rooting, plants are pinched by the grower to promote lateral branching. Pinching is labor intensive, messy due to poinsettia latex sap, and can spread disease. Described is a new product form which includes a poinsettia cutting that is callused and pre-pinched by the supplier before shipping to customer. The benefits to the grower include the ability to direct stick the cutting into the final container, no pinching required, and faster finish time.


Poinsettia cuttings are normally rooted and planted in a pot allowing the plant to establish roots before the plant is pinched to promote branching. The Eche Poinsettia Manual by Paul Ecke III et al. published by Ball Publishing (herein incorporated by reference) teaches that “Before pinching poinsettias, it is advisable to have adequate root systems established. The size of growing container and the volume of medium influence the time required for rooted cuttings to develop adequate roots prior to pinching.” Provided herein are methods to grow plants with improved growth habit by pinching unrooted cuttings.


SUMMARY

In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the stems of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the stems of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting, planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is 4 cm taller stems than a poinsettia pinched after planting and rooting.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit has about 3 fewer branches than a poinsettia pinched after planting and rooting.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the stems of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is 14 days faster to retail size than a poinsettia pinched after planting and rooting.


In some embodiments, a poinsettia plant with improved growth habit is provided produced by a method of growing from a callused, pinched cutting comprising the stems of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container.


In some embodiments, a method of producing a callused, pre-pinched Poinsettia cutting is provided comprising the stems of cutting a stem tip cutting and callusing the cutting and pinching the stem tip before planting.


In some embodiments, a callused, pre-pinched Poinsettia cutting is provided produced by a method comprising the stems of cutting a stem tip cutting, callusing the stem tip cutting, and pinching the stem tip before planting.


In some embodiments, a callused, pre-pinched Poinsettia cutting is provided.







DETAILED DESCRIPTION

Pinching refers to cutting a plant stem. Pinching can be performed with fingers, knife, scissors, pruning shears, or other sharp objects. Pinching results in a more branched plant habit. Where one stems is pinched, two new stems grow from the next stem node. Pinching also produces compact growth by reducing plant height. Crop time is the time from sticking the Poinsettia cutting in the final container to the opening of the cyathia.


Callus is formed by undifferentiated cells at a wound site often initiated under high moisture conditions. Callus formation protects the cutting from dehydration. Callus formation is a precursor to adventitious rooting. A standard Poinsettia cutting is 4.0 to 5.0 cm long when the cutting is harvested from the stock plant and has approximately four leaf nodes on the stem. Length is measured from the base of the cut stem to the shoot apical meristem. To create a pre-pinched callused Poinsettia cutting, the first step is to harvest a cutting from the stock plant that is 2.0 to 2.5 cm longer than a standard cutting (total length 6.0 to 7.0 cm) with one to three additional leaf nodes for a total of five to seven nodes. After harvest, the next step is callusing the cutting. The cutting of appropriate length and node count is stuck into a pre-made dibbled hole about 1 cm in diameter in an appropriate pre-wetted rooting medium (such as disinfected sand, rockwool, or peat moss). Rooting hormone [indole-3-butyric acid (IBA) or naphthaleneacetic acid (NAA)] may be applied as a liquid or powder dip to the base of the stem before sticking to accelerate the rooting process and improve uniformity. The rooting medium is usually contained in planting trays consisting of individual cells and these trays are on a raised bench in a greenhouse.


After sticking the cutting in the rooting medium, the cutting is misted with water regularly to retain turgidity. The ideal misting frequency should continually provide a film of water on the leaves and maintain humidity around 100%. Shade is applied over the propagation area to reduce stress on the cuttings and maintain 1,000-2,000 foot candles (200-300 μmol·m−2·s−1) during the brightest part of the day. The 24-hour average daily temperature of the rooting medium should be 22-26° C. (72-78° F.). Optional fertilizers, fungicides, insecticides, and plant growth regulators can be applied.


Callus formation at the base of the cut stem begins about 7 to 10 days after sticking in the medium and root tips are visible 10 to 14 days after sticking, depending on media, air temperature, and medium temperature. Approximately 17 to 21 days after sticking, the cuttings have developed roots approximately 2 to 3 cm long, and are ready to be harvested, pinched, and packaged for shipping to the customer. In this process, a greenhouse worker removes the rooted callused cutting from the propagation medium and then rubs off any roots with their fingers, leaving only the callus at the base of the cutting. The next step is pinching the distal shoot apical meristem off the cutting, removing one to two leaf nodes and leaving a minimum of four leaf nodes on the cutting. The shoot-tip pinch can be done manually by hand or with a disinfected knife. The removed shoot-tip is discarded and the remaining basal portion of the cutting with a minimum of four leaf nodes is the finished product.


Plant height and branch number were compared between plants grown from pre-pinched, callused cutting and non-pre-pinched callused cuttings as descried in example 2.









TABLE 1







Branch Number and Plant Height














Week
Variety


Number of
Height


Expt.
Stuck
Name
Treatment
Pl. #
Branches
(cm)
















Rep 1
30
Mirage ™
Non-pre-
1
7
26




Red
pinched


Rep 1
30
Mirage ™
Non-pre-
2
8
26




Red
pinched


Rep 1
30
Mirage ™
Non-pre-
3
7
24




Red
pinched


Rep 1
30
Mirage ™
Non-pre-
4
10
29




Red
pinched


Rep 1
30
Mirage ™
Non-pre-
5
8
27




Red
pinched


Rep 1
30
Mirage ™
Pre-Pinched
1
6
28




Red


Rep 1
30
Mirage ™
Pre-Pinched
2
4
31




Red


Rep 1
30
Mirage ™
Pre-Pinched
3
6
29




Red


Rep 1
30
Mirage ™
Pre-Pinched
4
6
29




Red


Rep 1
30
Mirage ™
Pre-Pinched
5
6
27




Red


Rep 2
32
Mirage ™
Non-pre-
1
8
23




Red
pinched


Rep 2
32
Mirage ™
Non-pre-
2
7
27




Red
pinched


Rep 2
32
Mirage ™
Non-pre-
3
10
19




Red
pinched


Rep 2
32
Mirage ™
Non-pre-
4
7
22




Red
pinched


Rep 2
32
Mirage ™
Non-pre-
5
8
21




Red
pinched


Rep 2
32
Mirage ™
Pre-Pinched
1
2
25




Red


Rep 2
32
Mirage ™
Pre-Pinched
2
5
27




Red


Rep 2
32
Mirage ™
Pre-Pinched
3
5
29




Red


Rep 2
32
Mirage ™
Pre-Pinched
4
7
31




Red


Rep 2
32
Mirage ™
Pre-Pinched
5
6
27




Red









The time taken to produce a finished plant was compared between plants started from pre-pinched, callused cuttings and plants started from non-pre-pinched, callused cuttings as described in example 2.









TABLE 2







Time to finished plant.

























Days:
Days:
Days:










Stick
Pinch
Stick



Week
Variety

Pl.
Finish
Stick
Pinch
to
to
to


Expt.
Stuck
Name
Treatment
#
Date
date
date
Finish
Finish
Pinch




















Rep
30
Mirage ™
Non-pre-
1
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
2
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
3
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
4
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
5
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
6
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
8
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
9
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
10
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
11
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red
pinched


Rep
30
Mirage ™
Non-pre-
12
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red
pinched


Rep
30
Mirage ™
Pre-Pinched
1
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
2
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
3
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
4
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
5
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
6
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
7
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
8
Nov. 19, 2019
Jul. 24, 2019
Aug. 29, 2019
118
82
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
9
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
10
Nov. 25, 2019
Jul. 24, 2019
Aug. 29, 2019
124
88
36


1

Red


Rep
30
Mirage ™
Pre-Pinched
12
Nov. 21, 2019
Jul. 24, 2019
Aug. 29, 2019
120
84
36


1

Red


Rep
32
Mirage ™
Non-pre-
1
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
2
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
3
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
4
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
5
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
6
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
7
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
8
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
9
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
10
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
11
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
12
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
13
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
14
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
15
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
16
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
17
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
18
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
19
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
20
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
21
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
22
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
23
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
24
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
MirageT
Non-pre-
25
Dec. 2, 2019
Aug. 7, 2019
Sep. 17, 2019
117
76
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
26
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
27
Dec. 2, 2019
Aug. 7, 2019
Sep. 17, 2019
117
76
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
28
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
29
Dec. 2, 2019
Aug. 7, 2019
Sep. 17, 2019
117
76
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
30
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
31
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
32
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
33
Dec. 2, 2019
Aug. 7, 2019
Sep. 17, 2019
117
76
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
34
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
35
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
36
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
37
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
38
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
39
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Non-pre-
40
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red
pinched


Rep
32
Mirage ™
Pre-Pinched
1
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
2
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
3
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
4
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
5
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
6
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
7
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
8
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
10
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
11
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
12
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
13
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
14
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
15
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
16
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
17
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
18
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
19
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
20
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
21
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
22
Nov. 19, 2019
Aug. 7, 2019
Sep. 17, 2019
104
63
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
23
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
24
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
25
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
26
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
27
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
28
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
29
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
30
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
31
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
32
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
33
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
34
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
35
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
36
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
37
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
38
Nov. 25, 2019
Aug. 7, 2019
Sep. 17, 2019
110
69
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
39
Dec. 2, 2019
Aug. 7, 2019
Sep. 17, 2019
117
76
41


2

Red


Rep
32
Mirage ™
Pre-Pinched
40
Nov. 21, 2019
Aug. 7, 2019
Sep. 17, 2019
106
65
41


2

Red
















TABLE 3





Days to Finish: From Cutting Stick to Finish



















Variable
N
R2
Adj R2
CV





DTF Stick-Finish
101
0.76
0.76
2.64










Analysis of variance table (Partial SS)





























Week
Treat-
Vari-



Mini-
Maxi-
wk to


S.V.
SS
df
MS
F
p-value

Stuck
ment
able
n
Mean
S.D.
mum
mum
finish
























Model
2710.94
3
903.65
105.03
<0.0001
30
Non-pre-
DTF
11
120.9
2.59
118
124
17.5









pinched
Stick-










Finish






















Week
2630.05
1
2630.05
305.7
<0.0001
***
30
Pre-
DTF
11
120.7
2.72
118
124
17


Stuck







Pinched
Stick-











Finish


Treatment
22.2
1
22.2
2.58
0.112
ns
32
Non-pre-
DTF
40
109.5
3.11
106
117
15.5










pinched
Stick-











Finish


Week
15.66
1
15.66
1.82
0.18
ns
32
Pre-
DTF
39
107.4
2.88
104
117
15.5


Stuck *







Pinched
Stick-


Treatment








Finish


Error
834.53
97
8.6


Total
3545.47
100

















Week Stuck
Means
n
S.E.









32
108.47
79
0.3
A



30
120.82
22
0.7

B







Means with a common letter are not significantly different (p > 0.05)
















TABLE 4





Days to Finish: From Pinch to Finish



















Variable
N
R2
Adj R2
CV





DTF pinch-finish
101
0.86
0.86
4.12










Analysis of variance table (Partial SS)





























Week
Treat-
Vari-
n
Mean
S.D.
Mini-
Maxi-
weeks to


S.V.
SS
df
MS
F
p-value

Stuck
ment
able



mum
mum
finish





Model
5266.29
3
1755.43
204.04
<0.0001

30
Non-pre-
DTF
11
84.91
2.59
82
88
12










pinched
pinch-











finish


Week
5187.59
1
5187.59
602.97
<0.0001
***
30
Pre-
DTF
11
84.73
2.72
82
88
12


Stuck







Pinched
pinch-











finish


Treat-
22.2
1
22.2
2.58
0.112
ns
32
Non-pre-
DTF
40
68.5
3.11
65
76
10


ment







pinched
pinch-











finish


Week
15.66
1
15.66
1.82
0.18
ns
32
Pre-
DTF
39
66.41
2.88
63
76
9.5


Stuck *







Pinched
pinch-


Treat-








finish


ment


Error
834.53
97
8.6


Total
6100.81
100

















Week Stuck
Means
n
S.E.









32
67.47
79
0.3
A



30
84.82
22
0.7

B







Means with a common letter are not significantly different (p > 0.05)
















TABLE 5





Number of Branches Statistics


Number of Branches



















Variable
N
R2
Adj R2
CV


Number of Branches
20
0.56
0.48
20.31










Analysis of variance table (Partial SS)















S.V.
SS
df
MS
F
p-value




Model
37.35
3
12.45
6.82
0.0036



Week Stuck
0.45
1
0.45
0.25
0.6262
ns



Treatment
36.45
1
36.45
19.97
0.0004
***



Week Stuck*Treatment
0.45
1
0.45
0.25
0.6262
ns



Error
29.2
16
1.83



Total
66.55
19


















Week Stuck
Treatment
Variable
n
Mean
S.D.
Minimum
Maximum





30
Non-pre-pinched
Number of
5
8
1.22
7
10




Branches


30
Pre-Pinched
Number of
5
5.6
0.89
4
6




Branches


32
Non-pre-pinched
Number of
5
8
1.22
7
10




Branches


32
Pre-Pinched
Number of
5
5
1.87
2
7




Branches





Treatment
Means
n
S.E.





Pre-Pinched
5.3
10
0.42
A


Non-pre-pinched
8
10
0.42

B

















Treatment
Means
n
S.E.





Pre-Pinched
5.3
10
0.42
A



Non-pre-pinched
8
10
0.42

B

















TABLE 6





Height Statistics







Height














Variable
N
R2
Adj R2
CV








Height (cm)
20
0.6
0.53
8.38










Analysis of variance table (Partial SS)














S.V.
SS
df
MS
F
p-value







Model
118.55
3
39.52
8.11
0.0017


Week Stuck
31.25
1
31.25
6.41
0.0222
*


Treatment
76.05
1
76.05
15.6
0.0011
**


Week Stuck*Treatment
11.25
1
11.25
2.31
0.1482
ns


Error
78
16
4.88


Total
196.55
19





Week Stuck
Treatment
Variable
n
Mean
S.D.
Minimum
Maximum





30
Non-pre-
Height
5
26.4
1.82
24
29



pinched
(cm)


30
Pre-Pinched
Height
5
28.8
1.48
27
31




(cm)


32
Non-pre-
Height
5
22.4
2.97
19
27



pinched
(cm)


32
Pre-Pinched
Height
5
27.8
2.28
25
31




(cm)







Test: Tukey Alpha: = 0.05 LSD: = 2.16192


Error: 5.2500 df: 17














Week Stuck
Means
n
S.E.









32
25.1
10
0.72
A


30
27.6
10
0.72

B


Means with a common letter are not significantly


different (p > 0.05)







Test: Tukey Alpha: = 0.05 LSD: = 2.16192


Error: 5.2500 df: 17














Treatment
Means
n
S.E.









Non-pre-pinched
24.4
10
0.72
A


Pre-Pinched
28.3
10
0.72

B


Means with a common letter are not significantly


different (p > 0.05)









In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 cm taller stems than a poinsettia pinched after planting and rooting.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit has about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 fewer branches than a poinsettia pinched after planting and rooting.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 or 36 days faster to retail size than a poinsettia pinched after planting and rooting.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is a crop time reduced 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 or 36 days.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is time from sticking to cyanthia opening and is reduced 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 or 36 days.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the poinsettia variety is selected from the group of Mirage™ Red, Titan® Red, and Gemma™ Red.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the final container is a 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21, 21.5, 22, 22.5, 23, 23.5, or 24 inch pot.


In some embodiments, a method of growing a poinsettia with improved growth habit from a callused, pinched cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container, wherein the poinsettia produced by callusing and pinching before planting has an improved growth habit, wherein the improved growth habit is measured comparing plants grown from callused cutting and pre-pinched callus cuttings grown under the same conditions,


In some embodiments, a poinsettia plant with improved growth habit is provided produced by a method of growing from a callused, pinched cutting comprising the steps of cutting a stem tip cutting, callusing the cutting, pinching the stem tip before planting and planting the cutting in the final container.


In some embodiments, a method of producing a callused, pre-pinched Poinsettia cutting is provided comprising the steps of cutting a stem tip cutting, callusing the cutting and pinching the stem tip before planting.


In some embodiments, a callused, pre-pinched Poinsettia cutting is provided produced by a method comprising the steps of cutting a stem tip cutting, callusing the stem tip cutting, and pinching the stem tip before planting.


In some embodiments, a callused, pre-pinched Poinsettia cutting is provided.


EXAMPLES
Example 1

A standard Poinsettia cutting is 4.0 to 5.0 cm long when the cutting is harvested from the stock plant and has approximately four leaf nodes on the stem. Length is measured from the base of the cut stem to the shoot apical meristem. To create a pre-pinched callused Poinsettia cutting, the first step is to harvest a cutting from the stock plant that is 2.0 to 2.5 cm longer than a standard cutting (total length 6.0 to 7.0 cm) with one to three additional leaf nodes for a total of five to seven nodes. After harvest, the next step is callusing the cutting. The cutting of appropriate length and node count is stuck into a pre-made dibbled hole about 1 cm in diameter in an appropriate pre-wetted rooting medium (such as disinfected sand, rockwool, or peat moss). Rooting hormone [indole-3-butyric acid (IBA) or naphthaleneacetic acid (NAA)] may be applied as a liquid or powder dip to the base of the stem before sticking to accelerate the rooting process and improve uniformity. The rooting medium is usually contained in planting trays consisting of individual cells and these trays are on a raised bench in a greenhouse.


After sticking the cutting in the rooting medium, the cutting is misted with water regularly to retain turgidity. The ideal misting frequency should continually provide a film of water on the leaves and maintain humidity around 100%. Shade is applied over the propagation area to reduce stress on the cuttings and maintain 1,000-2,000 foot candles (200-300 μmol·m−2·s−1) during the brightest part of the day. The 24-hour average daily temperature of the rooting medium should be 22-26° C. (72-78° F.). Optional fertilizers, fungicides, insecticides, and plant growth regulators can be applied.


Callus formation at the base of the cut stem begins about 7 to 10 days after sticking in the medium and root tips are visible 10 to 14 days after sticking, depending on media, air temperature, and medium temperature. Approximately 17 to 21 days after sticking, the cuttings have developed roots approximately 2 to 3 cm long, and are ready to be harvested, pinched, and packaged for shipping to the customer. In this process, a greenhouse worker removes the rooted callused cutting from the propagation medium and then rubs off any roots with their fingers, leaving only the callus at the base of the cutting. The next step is pinching the distal shoot apical meristem off the cutting, removing one to two leaf nodes and leaving a minimum of four leaf nodes on the cutting. The shoot-tip pinch can be done manually by hand or with a disinfected knife. The removed shoot-tip is discarded and the remaining basal portion of the cutting with a minimum of four leaf nodes is the finished product.


Example 2

The objective of this experiment was to evaluate the effects of a novel pre-pinch callused cutting (CC) on the height, branch number, and days to finish of poinsettia (Euphorbia pulcherrima). Two product forms of poinsettia CC: Pre-pinched (PP) and Standard (STD) were tested in Gilroy, California on week 30 (Jul. 24 2019, replication 1) and week 32 (Aug. 7 2019, replication 2). The pre-pinched CC were callused and pinched before shipping to the testing site. The STD CC were only callused and not pre-pre-pinched.


Upon delivery of the cuttings, they were all direct stuck into 1-quart (950 mL volume) finished containers with 1 plant per pot. After rooting into the media, the STD CC were pinched 5 weeks after stick. The PP CC did not have to be pinched because cuttings were already pinched by the supplier, which saved 20% labor during finishing. The pinch date in table 2 is the date that the control cc plants where pinched in the experiment. No plant growth regulators were used for this experiment. Days to anthesis (open cyathia) were collected on 12 pots from replication 1 and 40 pots from replication 2. Plant height measurements and number of branches were taken on 5 plants from each product form within each replication.


All poinsettias were propagated under long-days to prevent flowering (13.5 hour day lengths with 4 hours of night interruption). The propagation greenhouse was maintained at a 23° C. day/21° C. night temperature and a daily light integral (DLI) of 11.8 mols/day. All plant material moved to short day, inductive day lengths (11.5 hrs.) week 35 (Aug. 27 2019) until anthesis. The short-day greenhouse temperatures were 23° C. day/20° C. night with a DLI of 8.6 mols/day.


The PP CC were rooted and ready to transfer to the short-day greenhouse for flower initiation 1 to 2 weeks earlier than the STD CC. However, in this experiment the PP CC remained under long-days until the STD CC could catchup and develop enough vegetative growth so both treatments could be transferred to short days at the same time. At the time of transfer, the PP CC were taller than STD CC. After the start of short days, all plants finished in 12 weeks. If the PP CC had been transferred sooner to short-days, plants would have flowered and shipped to market 1 to 2 weeks earlier, saving significant growing costs.


The PP CC were 4 cm taller at finish and had a mean of 3 less branches per plant than the standard treatment. Surprisingly, the PP CC produced acceptable retail quality plants even though they had on average 5.3 branches. Transferring the PP CC to short days 2 weeks earlier when they were ready would have likely reduced the 4 cm height difference between treatments. This experiment showed that the novel PP CC poinsettia can produce a marketable finished plant with 20% fewer labor inputs and up to 2 weeks shorter growing time.









TABLE 7







Replications 1 and 2 averages of plant height and number of


branches 18 weeks after sticking cuttings into 1-quart pots.













Treatment
Height (cm)

Number of Branches

















Pre-pinched CC
28.3
b*
5.3
a



Standard CC
24.4
a
8.0
b







*Means within a column followed by the same letter are not significantly different according to Tukey comparison at P ≤ 0.05.






Example 3

The objective of this experiment was to evaluate the effects of a novel pre-pinch callused cutting (CC) on the height, branch number, and days to finish of poinsettia varieties: Mirage™ Red, Titan® Red, and Gemma™ Red. A trial was performed in Monroeville, NJ, (Week 32-50, 2020) comparing standard callused cutting (CC) versus pre-pinched callused (PPCC) poinsettia cutting to evaluate its effects on flowering time and finish quality of Mirage™ Red, Titan® Red, and Gemma™ Red. Fifty plants were grown for each variety in each treatment. Average data values are shown in Table 8. The first shipment were direct stuck into 6.5″ pots and the second shipment were direct stuck into 4″ pots and grown inside a greenhouse at an Average Daily Temperature, ADT, of 72.05° F. (22.25° C.), Daily Light Integral, DLI, of 19 mols/day, and naturally decreasing day length of 14.5-10.5 hours. The 4″ and 6.5″ standard CC's were pinched to 5 and 7 nodes, respectively. Although the PPCC's had fewer branches, their bracts were more expanded, plants were taller, and the cyathia opened 1-2.5 weeks earlier than the standard CC; standard CC and PPCC received the same PGR regime.


These observations indicate that the PPCC's had a jump start in growing after the pinch versus the standard CC's, thus reaching finished shipping stage earlier. Overall, the trial contributed to further proving the technical concept of pre-pinching a callused poinsettia cutting to be able to produce a marketable plant in a shorter time period with good quality while reducing labor inputs

















TABLE 8













Crop










Time







Average
Average

(from



Week
Pot
Variety

Branch
Height
Flowering Date
stick


Expt.
Stuck
Size
Name
Treatment
Number
(cm)
(Open Cyathia)
date)























3
32
6.5″
Mirage ™
Standard CC
6
22.5
Nov. 23, 2020 (wk 48)
16





Red


3
33
6.5″
Mirage ™
Pre-Pinched
4
26.5
Nov. 19, 2020 (wk 47)
14.4





Red
CC


3
32
6.5″
Titan ® Red
Standard CC
6
19
Nov. 17, 2020 (wk 47)
15.1


3
33
6.5″
Titan ® Red
Pre-Pinched
4
26
Nov. 13, 2020 (wk 46)
13.6






CC


3
32
6.5″
Gemma ™
Standard CC
6.5
33.5
Dec. 9, 2020 (wk 50)
18.3





Red


3
33
6.5″
Gemma ™
Pre-Pinched
4
39
Dec. 5, 2020 (wk 49)
16.7





Red
CC


3
34
4.0″
Mirage ™
Standard CC
5
14
Nov. 23, 2020 (wk 48)
14





Red


3
35
4.0″
Mirage ™
Pre-Pinched
4.5
20
Nov. 19, 2020 (wk 47)
12.4





Red
CC


3
34
4.0″
Titan ® Red
Standard CC
5
15.5
Nov. 17, 2020 (wk 47)
13.1


3
35
4.0″
Titan ® Red
Pre-Pinched
4
17.5
Nov. 13, 2020 (wk 46)
11.6






CC


3
34
4.0″
Gemma ™
Standard CC
5
21
Dec. 14, 2020 (wk 51)
17





Red


3
35
4.0″
Gemma ™
Pre-Pinched
4
30
Dec. 7, 2020 (wk 50)
15





Red
CC








Claims
  • 1. A method of growing a poinsettia with improved growth habit from a callused, pinched cutting comprising the steps of: A) Cutting a stem tip cutting,B) Callusing the cutting,C) Pinching the stem tip before planting,D) Planting the cutting in the final container,
  • 2. The method of claim 1, wherein the improved growth habit is about 4 cm taller stems than a poinsettia pinched after planting and rooting.
  • 3. The method of claim 1, wherein the improved growth habit has about 3 fewer branches than a poinsettia pinched after planting and rooting.
  • 4. The method of claim 1, wherein the improved growth habit is 14 days faster to retail size than a poinsettia pinched after planting and rooting.
  • 5. A plant produced from the method of claim 3.
  • 6. A method of producing a callused, pre-pinched poinsettia cutting comprising the steps of cutting a stem tip cutting and callusing the cutting, pinching the stem tip before planting.
  • 7. A callused, pre-pinched poinsettia cutting produced by the method of claim 6.
RELATED APPLICATIONS

This application claims priority from provisional application 63/079,491 filed Sep. 17, 2020 and incorporated by reference in its entirety herein.

PCT Information
Filing Document Filing Date Country Kind
PCT/US2021/050579 9/16/2021 WO
Provisional Applications (1)
Number Date Country
63079491 Sep 2020 US