U.S. patent application number 14/517244 was filed with the patent office on 2015-02-05 for use of photosynthetic pigment stabilizing agents to regulate ripening and quality in fruits and vegetables.
The applicant listed for this patent is Washington State University. Invention is credited to Amit DHINGRA, Scott SCHAEFFER.
Application Number | 20150037476 14/517244 |
Document ID | / |
Family ID | 47218036 |
Filed Date | 2015-02-05 |
United States Patent
Application |
20150037476 |
Kind Code |
A1 |
DHINGRA; Amit ; et
al. |
February 5, 2015 |
USE OF PHOTOSYNTHETIC PIGMENT STABILIZING AGENTS TO REGULATE
RIPENING AND QUALITY IN FRUITS AND VEGETABLES
Abstract
Methods and compositions to temporarily delay the ripening,
maturation, senescence and pathogen infection of produce such as
fruits, vegetables and ornamental plants are provided. The methods
involve the application of a photosynthetic pigment and/or membrane
stabilizing chemical (e.g. glycine betaine) to produce which is
identified as in need of such delay. Application may be prior to
harvest, at or during harvest or post-harvest.
Inventors: |
DHINGRA; Amit; (Pullman,
WA) ; SCHAEFFER; Scott; (Bremerton, WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Washington State University |
Pullman |
WA |
US |
|
|
Family ID: |
47218036 |
Appl. No.: |
14/517244 |
Filed: |
October 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13826860 |
Mar 14, 2013 |
8901039 |
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14517244 |
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PCT/US12/39038 |
May 23, 2012 |
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13826860 |
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61489103 |
May 23, 2011 |
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Current U.S.
Class: |
426/310 |
Current CPC
Class: |
A23V 2002/00 20130101;
A23B 7/154 20130101; A01N 37/44 20130101; A01N 37/44 20130101; A01N
27/00 20130101 |
Class at
Publication: |
426/310 |
International
Class: |
A23B 7/154 20060101
A23B007/154 |
Claims
1-12. (canceled)
13. A method of delaying or slowing the ripening or maturation of
apples, comprising the steps of identifying apples for which
delaying or slowing ripening or maturation, senescence, or pathogen
entry is desirable; and applying glycine betaine to said apples,
wherein said step of applying is carried out at or after
harvest.
14-15. (canceled)
16. The method of claim 13 wherein said applying step includes
applying an anti-ripening agent selected from the group consisting
of 1-methylcyclopropene (1-MCP) and aminoethoxyvinylglycine HCl.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. provisional patent
application 61/489,103, filed May 23, 2011, and claims benefit of
and is a continuation-in-part of International patent application
PCT/US12/39038, filed May 23, 2012, the complete contents of both
of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention generally relates to methods for delaying the
abscission, preharvest drop, ripening, maturation, senescence or
pathogen entry of produce such as fruit and vegetables. In
particular, the invention provides a method of temporarily
preventing or delaying the ripening or maturation of produce by the
pre- or post-harvest application of a photosynthetic pigment or
membrane stabilizing agent and osmoregulaor such as glycine
betaine.
[0004] 2. Background of the Invention
[0005] Postharvest treatment with the synthetic molecule
1-methylcyclopropene (1-MCP) is used by the fruit industry to slow
the ripening process of fruit during storage. 1-MCP treatment
extends the shelf life of treated fruit, thereby increasing the
availability of fresh fruit to consumers throughout much of the
year. 1-MCP is structurally related to the natural plant hormone
ethylene and slows ripening by binding to ethylene receptors,
thereby blocking the binding of ethylene and preventing a ripening
response to the hormone. In some cases, over time, the effect of
1-MCP treatment wanes and ripening of the treated commodity can
occur. The use of 1-MCP in this manner is described in U.S. Pat.
No. 6,017,849, the complete contents of which are hereby
incorporated by reference in entirety.
[0006] Unfortunately, certain fruits do not respond well to 1-MCP.
For example, applications of 1-MCP have had mixed success in pear
storage, often yielding pears that are unable to ripen at all after
treatment. The resulting pears remain hard and have relatively low
levels of soluble sugars, which impair their taste and appeal to
consumers. For these and other types of fruit, there is a need in
the industry to provide alternative methods for the treatment of
fruit to slow the ripening process. It would also be desirable to
have available an anti-ripening agent that is a natural product
rather than a synthetic such as 1-MCP.
[0007] Several attempts to control or delay ripening of fruits and
vegetables during transport and storage have been made. For
example, U.S. Pat. Nos. 6,124,525, 6,080,914, 5,952,546 and
5,512,466 describe various genetic modifications of plants that may
be used to alter the ripening process. However, the use of
genetically modified organisms is generally not popular with the
public at large, may have far-reaching and unpredictable
environmental consequences, and requires a high degree of
government regulation.
[0008] U.S. Pat. No. 7,943,549 to Pierce et al. describes methods
for delaying a plant development process by exposing a plant or
plant part to one or more bacteria or enzymes. Bacteria such as
Rhodococcus spp., Pseudomonas chloroaphis, and Brevibacterium
ketoglutamicum may be used. However, the use of live organisms can
be fraught with problems since they are sensitive to environmental
conditions, and control of the process (e.g. reversibility) may be
difficult. In addition, the public may be reluctant to consume
produce that has been "infected" with bacteria.
[0009] Glycine betaine is known to be used as an osmolyte regulator
when applied to fruit before harvesting so as to prevent or reduce
blemishes or damage of the skin of the fruit (e.g. to reduce cherry
cracking; see U.S. Pat. No. 5,972,840 to Mottram, the complete
contents of which are hereby incorporated by reference). However,
U.S. Pat. No. 5,972,840 makes no mention of the use of glycine
betaine to forestall ripening or prevent pathogen entry of fruit or
other produce.
[0010] In addition to its role in ripening, ethylene plays a role
in abscission, the process of a plant intentionally shedding an
organ. Plants naturally use the process of abscission to drop fruit
at the end of a growing season. While this process is beneficial in
nature, dropping fruit before harvest leads to large losses in the
agricultural world. U.S. Pat. Nos. 5,869,424 and 6,153,559
addresses this issue through the application of
aminoethoxyvinylglycine (commercially named RETAIN.RTM.) and its
precursor N-acetyl aminoethoxyvinylglycine, respectively, to
inhibit ethylene biosynthesis. An alternative strategy was
described in US patent US 2012/0101164 A1 where application of
1-naphthaleneacetic acid (NAA) also delayed the abscission of
fruit. However, these approaches act through different mechanistic
properties compared to glycine betaine.
SUMMARY OF THE INVENTION
[0011] The present invention provides methods and compositions for
slowing or controlling the timing of the ripening, maturation,
senescence, abscission or preventing pathogen entry of produce, for
example, fruit, vegetables, ornamental plants, etc. The methods
involve the application of a photosynthetic pigment or membrane
stabilizing agent such as glycine betaine to the produce pre- or
post-harvest (or both), thereby lengthening the time period during
which the produce can be transported and stored before being made
available to consumers. The delay in ripening or maturation is
advantageously reversible: with the passage of time, the effects of
e.g. glycine betaine decrease, and ripening occurs. The methods are
especially useful for treating produce that does not respond well
to the application of 1-MCP, e.g. pears. However, the application
of the stabilizing agent may be used for any and all produce in
place of or in conjunction with 1-MCP or other agents, in order to
modulate or control the ripening and/or maturation processes, and
to temporarily prevent or slow the onset of senescence.
[0012] The practice of the invention will advantageously impact the
produce (e.g. fruit and vegetable) industry in at least the
following ways:
[0013] 1) The use of the invention allows for the regulation of
ripening so that the maturation process of produce is controlled
and/or delayed e.g. senescence is delayed, and reduced amounts of
soluble solids are maintained;
[0014] 2) The use of the invention decreases the incidence of fruit
drop, or organ abscission, enabling a longer growing season or
delaying harvest time;
[0015] 3.) The use of the invention as described herein to reduce
incidence of preharvest, at harvest, or postharvest pathogen entry
from bacteria, fungi, or other pathogens of produce.
[0016] 4) The use of the invention provides an alternative to 1-MCP
and the effects of glycine betaine, unlike 1-MCP, are
reversible;
[0017] 5) The use of the invention decreases rates of damage during
shipment of e.g. pears and/or other commodities due to the
preservation or maintenance of increased firmness after
application;
[0018] 6) Organic preparations can be formulated, which is not
possible with 1-MCP in certain cases; and
[0019] 7) The use of glycine betaine as described herein in
combination with e.g. low levels of 1-MCP or other products that
interfere with ethylene-related or unrelated ripening processes
advantageously allows for a synergistic slowing of ripening via
multiple mechanisms. Suitable ratios of glycine betaine to another
product in a mixture may range from e.g. about 90:10 to 10:90,
including e.g. 50:50; or from about 65:35 to 35:65; or from about
75:25 to 25:75, etc;
[0020] It is an object of this invention to provide a method of
delaying or slowing the ripening, maturation, abscission, or
senescence of produce, or preventing pathogen entry into produce.
The method comprises the steps of 1) identifying produce for which
delaying or slowing ripening, maturation, abscission, senescence,
or pathogen entry is desirable, and 2) applying a photosynthetic
stabilizing agent to said produce. In some embodiments of the
invention, the photosynthetic stabilizing agent is glycine betaine.
The produce comprises, for example, fruits, vegetables, and/or
ornamental plants. In some cases, the produce is a pear such as a
d'Anjou pear. The step of applying may be carried out at one or
more of before harvest, at harvest, or after harvest.
Alternatively, or in addition, the step of applying may be carried
out during shipping. Application may be by spraying, fogging,
dipping, or by infiltration. The step of applying may utilize
specific concentrations of photosynthetic stabilizing and requires
human intervention, e.g. human intervention in one or more of the
processes of ripening, maturation, abscission, and/or senescence of
produce, and/or preventing pathogen entry into produce.
[0021] The invention also provides a method of delaying or slowing
the ripening, maturation, abscission or senescence of and
preventing pathogen entry into pears. The method comprises the
steps of 1) identifying pears for which delaying or slowing
ripening, maturation, abscission or senescence and preventing
pathogen entry is desirable, and 2) applying a photosynthetic
stabilizing agent to said pears. In some embodiments, the
photosynthetic stabilizing agent is glycine betaine.
[0022] The invention further encompasses a composition comprising
1) glycine betaine, 2) 1-methylcyclopropene (1-MCP), and 3) a
carrier suitable for application to produce. The invention further
encompasses a composition comprising 1) glycine betaine, 2),
aminoethoxyvinylglycine HCl, and 3) a carrier suitable for
application to produce. The invention further encompasses a
composition comprising 1) glycine betaine, 2), 1-naphthaleneacetic
acid, and 3) a carrier suitable for application to produce.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1. Fruit pressure of Bluestim.TM. (glycine
betaine)-treated and untreated d'Anjou pears. D'Anjou pears were
treated on trees with Bluestim.TM. concentrations of 0, 2.5, 5, and
10 lbs/acre on Aug. 17, 2010. Pears were harvested on Sep. 20, 2010
and stored in commercial controlled atmosphere (CA) facilities.
Pears were removed from storage on Jan. 7, 2011.
[0024] FIG. 2. Percent Brix of Bluestim.TM.-treated pears after CA
storage. Percent Brix were measured for all pear treatments after
they were removed from the commercial CA storage conditions.
[0025] FIG. 3. Fruit pressure of Bluestim.TM. (glycine
betaine)-treated and untreated d'Anjou pears. D'Anjou pears were
treated on trees with Bluestim.TM. concentrations of 0 and 7.5
lbs/acre before harvest. Pears were harvested during the fall and
stored in commercial controlled atmosphere (CA) facilities. Pears
were removed from storage approximately 3 months later. Fruit
firmness and % Brix were measured approximately I month after
removal from storage.
DETAILED DESCRIPTION
[0026] The present invention provides methods and compositions that
temporarily prevents or delays one or more of the ripening,
maturation, abscission and senescence of, and/or prevention of
pathogen entry into, produce such as fruits and vegetables.
Further, the methods and compositions preserve the freshness of
ornamental plants. The compositions comprise a photosynthetic
membrane and/or pigment stabilizing agent such as glycine betaine,
a natural product found in most fruit, vegetable and animal
species. Without being bound by theory, it is believed that the
external application of such an agent to produce that is not yet
ripe or which is in the process of ripening slows the breakdown of
photosynthetic pigment, which usually accompanies and/or
participates in the ripening process. As a result of the slowing of
photosynthetic membrane and/or pigment and protein complex
breakdown, ripening or maturation of the produce is also slowed.
However, the effect is not permanent.
[0027] With time, the effects of the application decrease or
reverse, and ripening/abscission/senescence/maturation proceeds in
a normal manner. The application of e.g. glycine betaine thus
reversibly prolongs the firmness of produce and retards the
conversion of starches to soluble sugars, both of which are
considered in the art to be indicators of ripening. The use of such
an agent is particularly advantageous for use with e.g. pears,
which can be problematic since they often fail to ripen at all (or
only minimally) after exposure to conventional agents such as
1-MCP. The prolongation of ripening and/or maturation and/or the
delay of abscission and/or the delay of senescence facilitates
storage and transportation of produce, both with respect to time
(i.e. the time of storage can be extended without loss due to
spoilage), and with respect to decreasing damage that otherwise
occurs during shipping and handling of softened, softening or
wilting produce. Additionally, stabilization of membranes promotes
the ability of the produce to withstand infection by pathogens.
[0028] By "prevention of pathogen entry" or "prevention of pathogen
entry into" we mean that the use of glycine betaine slows or
prevents or lessens the amount or extent of pathogen invasion or
infestation of the plant or produce, compared to corresponding
plants/plant tissue that is/are exposed to the pathogen under
comparable conditions but without treatment with glycine betaine.
Such invasion or infection may be, for example, actual entry of the
pathogen (e.g. by boring, chewing, enzyme secretion, etc.) into
plant tissue; or the eating of plant tissue at or near the surface;
or the insertion of body parts of the pathogen into plant tissue
(e.g. feeding or reproductive appendages); or the placement of
reproductive means (e.g. the laying of eggs) in or on plant tissue;
or the establishment of a colony in or on the plant or plant
tissue, etc. Pathogens, pests and parasites that may be prevented
from infecting plants, produce, etc. by the use of glycine betaine
include but are not limited to: various rusts and blights; insects;
nemartodes; fungi, bacteria, viruses, mildews, aphids, etc.
[0029] In one embodiment, the photosynthetic stabilizing agent is
glycine betaine. While much of the discussion herein refers to
glycine betaine, the discussion can apply equally to other
photosynthetic stabilizing agents or precursors of glycine betaine
such as choline or betainealdehyde, examples of which include but
are not limited to: chlorophyllase inhibitors such as diisopropyl
fluorophosphates, thylakoid membrane stabilizers such as spermine
and 1,3-diaminopropane etc.
[0030] Glycine betaine (also known as betaine, trimethylglycine or
"TMG", betaine anhydrous, N,N,N-trimethylglycine, etc.) is a
natural compound that occurs in plants and animals as either
glycine betaine or a choline-containing glycine betaine compound
which can be enzymatically cleaved to form glycine betaine. First
discovered in sugar beets, glycine betaine is produced abundantly
as a byproduct of the manufacture of e.g. molasses and sugar from
sugar beets and sugar cane. Significantly, this substance is known
to be non-toxic and thus its use on comestible substances is safe
with respect to consumption by humans or other animals. Betaine is
already known for use as an animal feed supplement; in products for
skin, hair and oral care (e.g. as a moisturizer and protectant); as
a de-icing agent; as a sports performance enhancing agent that is
added to e.g. sports drinks; and for other purposes. It is thus
readily available commercially, for example, from Finnfeeds
Finland, in Naantali, Finland, as the product BLUESTIM.RTM. (97%
solution of betaine), and in various forms from the Danisco
company; or as "Glycine Betaine" from Sunwin in China; or as
"Prostim" "GREENSTIM.RTM." or "Jinsaeng" from Agrogenesis in
Finland (see, for example the websites located at
www.agro-genesis.cam/product_environmentalcare_turf.htmland and the
website located at
www.agro-genesis.com/product_cropscience_phyto.html; etc.
[0031] The glycine betaine that is used as described herein may be
"organic", by which we mean that the source of the glycine betaine
can be produced using methods that do not involve synthetic inputs
such as synthetic pesticides, chemical fertilizers, etc. and,
optionally, are not genetically modified or processed using
irradiation, industrial solvents, or chemical food additives.
Various standards of "organic" have been established in many
countries and locations, including the United States, European
countries, South American countries, and others. These standards
may vary somewhat from location to location, but in general the
definition provided above is what is intended when the term is used
herein.
[0032] With respect to its use on produce as described herein,
glycine betaine may be applied "as is" from a commercial source, or
may be formulated or reformulated into a preparation that is used
for application. Glycine betaine may be applied, for example, as a
liquid solution that contains, e.g. at least about 10, 20, 30, 40,
50, 60, 70, 80, 90, or even about 100% glycine betaine, so long as
the formulation is suitable for application, and so long as the
applied solution adheres to or is retained at least partially on
the surface of the produce or plant that is being treated. Further,
glycine betaine is not always applied as a liquid; solid forms
(e.g. crystals, dusts, aerosols, etc.) of this agent are also
contemplated and encompassed by the invention, as are various gels
or other forms. In addition, various substances that are not active
(i.e. are inert) with respect to ripening in particular, or to
produce in general, may be included in such formulations. For
example, agents that aid in preparation or application of the
formulation, or in retention of the glycine betaine on the produce
after application, or for any other reason may be included, e.g.
preservatives, colorants, detergents, various emulsifiers,
diluents, buffering agents, salts, oils, lipids, waxes, solvents,
penetrants, paper wrappings, packaging, storage boxes. Glycine
betaine may also be directly infiltrated via vacuum or injected to
retard ripening.
[0033] In addition, glycine betaine may be used alone or in
combination with one or more other active agents which
affect/improve/slow, etc. the ripening process, or which are
beneficial to produce in some other way. By "used together" or "in
combination" we mean that the two (or more, i.e. a plurality of)
agents may be applied 1) separately one after the other within a
relatively short period of time (e.g. simultaneously from separate
preparations, or within minutes or hours, or the same day, or
within a few days, etc.); or 2) the two or more agents may be mixed
together into a single formulation that is applied. Glycine betaine
may thus be used in combination with 1-MCP, other anti-ripening
agents such as lysophosphatidylethanolamine; silver agents,
aminoethoxyvinylglycine, aminooxyacetic acid, potassium
permanganate (ethylene absorbent), aminoethoxyvinylglycine HCl,
1-naphthaleneacetic acid, etc. Additional active ingredients or
additives that may be present in such compositions include but are
not limited to: various antimicrobial substances; various
antifungal agents; various insecticides; various pesticides;
hormones, biotic applications, etc. For example, see U.S. Pat. Nos.
5,110,341; 6,177,072; and 7,150,884, the complete contents of each
of which are hereby incorporated by reference, for a description of
some exemplary ingredients or additives with which glycine betaine
may be combined. Generally, the amount of glycine betaine in such a
composition is from about 1 to about 99%.
[0034] Those of skill in the art will recognize that the amount of
glycine betaine that is applied may vary from circumstance to
circumstance, e.g. according to the produce that is being treated,
according to the desired amount of delay that is desired, according
to the environment during delivery (e.g. in an orchard vs in a
shipping container), according to weather conditions, etc. In
general, the amount for application "in the field" e.g. in an
orchard, filed, etc. is from about 0.5 to about 50, or from about 1
to about 15, or from about 2.5 to 10, e.g. about 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 19, 20, 25, 30, 35, 40,
45 or 50 pounds per acre. For other scenarios, such as in shipping
containers, about 20, 40, 60, 80 or 100 pounds is applied.
[0035] According to the invention, glycine betaine may be applied
to any type of produce, (including fruit, vegetables, and
ornamental plants) for which it is desirable to slow maturation.
Thus, the term "produce" as used herein is intended to be
interpreted broadly, and to include plant-based agricultural
products that are typically referred to as fruits, vegetables,
grasses, grains, ornamental plants, bulbs, nuts, etc.
[0036] With respect to fruit, those of skill in the art will
recognize that the word "fruit" may have a variety of meanings. For
example, standard definitions include: 1. edible part of plant: an
edible part of a plant, usually fleshy and containing seeds; 2.
ovary of a plant: the ripened seed-bearing ovary of a plant; and 3.
produce: the produce of any plant grown or harvested by humans. In
broad terms, "fruit" may refer to a structure of a plant that
contains its seeds. In non-technical usage, such as food
preparation, "fruit" may refer to the fleshy seed-associated
structures of certain plants that are sweet and edible in the raw
state, such as apples, oranges, grapes, strawberries, juniper
berries, bananas, etc., although non-sweet or less sweet fleshy
structures (e.g. root vegetables such as carrots, beets, sweet
potatoes, yams, etc.) are also included. Seed-associated structures
that do not fit these informal criteria may be referred to by other
names, such as vegetables, pods, ears, etc. In the botany of
flowering plants, a "fruit" is a part that derives from specific
tissues of the flower, mainly one or more ovaries. Taken strictly,
this definition excludes many structures that are "fruits" in the
common sense of the term, while including many structures that are
not commonly called "fruits", such as bean or pea pods, corn
kernels, tomatoes, etc. all of which are encompassed by the present
invention.
[0037] Many fruits that, in a botanical sense, are true fruits are
actually treated as vegetables in cooking and food preparation,
including cucurbits (e.g., squash, pumpkin, gourds, melons,
cucumbers, etc.), tomatoes, peas, beans, corn, eggplant, and sweet
pepper, as wells as some spices, such as allspice and chilies.
[0038] As used herein, the term "fruit" refers to all plant
products encompassed by the botanical, culinary and common meanings
of the word.
[0039] Exemplary types of fleshy, simple fruits encompassed by the
invention include but are not limited to: stone fruit or drupe
(e.g. plum, cherry, peach, apricot, olive, mango, etc.); pome
fruits of the family Rosaceae, (including apples, pears, rosehips,
saskatoon berry, etc.); aggregate fruits such as achenes (e.g.
strawberry), follicles, drupelets (raspberry and blackberry), and
various other berries; multiple fruits such as pineapple, fig,
mulberry, osage-orange, breadfruit, hedge apple, etc; citrus fruits
such as oranges, lemons limes, grapefruits, kumquats, tangelos, ugh
fruit, tangerines, tangelos, minnolas, etc.; so-called "true"
berries such as black current, red current, gooseberry, tomato,
eggplant, guava, lucuma, chilis, pomegranates, kiwi fruit, grape,
cranberry, blueberry, etc.; including both seeded and seedless
varieties, as well as hybrid and genetically altered or manipulated
varieties; and others such a avocados, persimmons, etc.
[0040] In one embodiment of the invention, the fruit that is
treated using the methods and compositions of the invention is a
pear. By "pear" we mean the fruit of a member of the genes Pyrus,
examples of which include but are not limited to: Pyrus
amygdaliformis (Almond-leafed pear); Pyrus armeniacifolia; Pyrus
boissieriana; Pyrus bourgaeana (Iberian pear);
Pyrus.times.bretschneideri (Chinese white pear; also classified as
a subspecies of Pyrus pyrifolia); Pyrus calleryana (Callery pear);
Pyrus communis (European pear); Pyrus communis subsp. communis
(European pear cultivars of which include Beurre d'Anjou, Bartlett
and Beurre Bosc); Pyrus communis subsp. caucasica (syn. P.
caucasica); Pyrus communis subsp. pyraster (wild European pear
(syn. Pyrus pyraster); Pyrus cordata (Plymouth pear); Pyrus
cossonii (Algerian pear); Pyrus dimorphophylla; Pyrus elaeagnifolia
(oleaster-leafed pear); Pyrus fauriei; Pyrus gharbiana; Pyrus
glabra; Pyrus hondoensis; Pyrus koehnei (evergreen pear of southern
China and Taiwan); Pyrus korshinskyi; Pyrus mamorensis; Pyrus
nivalis (snow pear); Pyrus pashia (Afghan pear);
Pyrus.times.phaeocarpa; Pyrus pseudopashia; Pyrus pyrifolia (Nashi
pear, Sha Li); Pyrus regelii; Pyrus salicifolia (willow-leafed
pear); Pyrus.times.serrulata; Pyrus.times.sinkiangensis (thought to
be an interspecific hybrid between P..times.bretschneideri and
Pyrus communis); Pyrus syriaca; Pyrus ussuriensis (Siberian pear)
and Pyrus xerophila.
[0041] Major types of pears which are marketed and which may be
treated by the methods and compositions of the invention include
but are not limited to: Williams' Bon Chreetien (sold in the United
States. as Bartlett), Red Bartlett varieties, d'Anjou, Bosc,
Cornice, Abate Fatelle, Concorde, and Seckel pears.
[0042] Glycine betaine may also be used to slow the development,
ripening, maturation, abscission, or onset or progression of
senescence of, or to prevent pathogen entry into, vegetables. As
used herein, the term "vegetable" refers to an edible plant or part
of a plant, and typically means the leaf, stem, or root of a plant
but also includes some "fruits" as well (such as squash, see
above). The meaning of this word is largely based on culinary and
cultural tradition and all common meanings that are recognized by
those of skill in the art are encompassed herein. Vegetables may be
categorized as allium, brassica or cruciferous, composite, gourds,
umbelliferous, amaranth, grass, morning glory, nightshade, legumes,
root, leafy green, etc. and all such vegetables may be treated
using the methods and compositions of the invention.
[0043] Glycine betaine may also be used to slow the development,
maturation, abscission, or senescence of, or prevent pathogen entry
into, ornamental plants and hence to preserve their freshness. As
used herein, the phrase "ornamental plant" refers to plants that
are grown for decorative purposes such as e.g., house plants, those
grown for cut flowers, etc. as well as certain grasses, annuals,
perennials, shrubs, trees, etc. As used herein the phrase has the
same meaning that it is generally used in the horticultural
trades.
[0044] The application of glycine betaine to produce or plants may
be carried out at any time at which it is desired to delay the
onset and/or the progression of development, ripening, maturation,
abscission, pathogen entry etc. In addition, various life stages of
plants may be treated, e.g. sprouts, shoots or seedlings, etc. The
methods of the invention involve identifying produce for which a
delay in ripening, maturation, abscission, senescence, or pathogen
entry is desired or suitable, and treating the produce as described
herein. Accordingly, when treating produce, the produce may still
be on the tree (or other plant from which it develops and grows),
or may have already been harvested. The produce may be in any
"stage" of ripening or maturation. For example, the produce (e.g.
after harvest in the orchard, after harvest and when packed in a
shipping container, etc.) may have characteristics of immature,
"green" or "un-ripe" produce such as very low sugar content, high
stringency, high "firmness", lack of colorful pigment, undeveloped
or developing buds that have not bloomed, etc. Alternatively, the
produce may have begun to mature or ripen in that e.g. the sugar
content has begun to increase, firmness has begun to dissipate, the
size has increased, blooming or flowering has (at least partially)
commenced, etc. but the process is not complete. In yet other
embodiments, the produce may be approaching maturity, but the
application of glycine betaine causes suspension of further
progression of sugar increase, softening, etc. so that the produce
is "arrested" in a ripened or mature state and spoilage and
senescence is prevented or slowed or deferred. In short, glycine
betaine may be applied to produce at a stage prior to the onset of
degradation of photosynthetic pigments in order to delay further
ripening or maturation of the produce. In addition, glycine betaine
may be applied repeatedly to produce or plants in order to extend
its effects over a longer period of time.
[0045] In one embodiment, the methods of the invention are carried
out before a fruit is "ripe", i.e. before the fruit has a soluble
solids content or "SSC" (which generally corresponds to sugar
content) that is generally recognized in the art as suitable for a
fruit of interest. Those of skill in the art will recognize that
this number or range varies widely from fruit to fruit. Percent
sugar content is typically measured, for example, in degrees Brix
(symbol .degree. Bx) which is the sugar content of an aqueous
solution. One degree Brix is 1 gram of sucrose in 100 grams of
solution and represents the strength of the solution as percentage
by weight (% w/w) (strictly speaking, by mass). If the solution
contains dissolved solids other than pure sucrose, then the
.degree. Bx is only approximate the dissolved solid content. Those
of skill in the art will recognize that typical Brix values for
fruit and vegetables to which glycine betaine is applied as
described herein will vary widely depending on the type of fruit or
vegetable, and will be able to readily able to determine suitable
values.
[0046] SSC values may be determined by various means, for example,
by refractometry, by using various visible/near infrared (Vis/NIR)
transmittance techniques, etc.
[0047] In addition, the degree of firmness and/or lack thereof may
be used as an indicator of ripeness. Fruit thinness is generally
measured as kg/cm.sup.-2 and suitable ranges of firmness values for
unripened and ripe fruit and vegetables are well-known to those of
skill in the art. Firmness may be measured using a variety of
instruments such as various fruit firmness testers, force gauges,
etc.
[0048] In addition, other criteria may also be employed to
determine the extent of ripeness (or lack thereof) of a fruit, for
example, color, aroma, free acids, starch content, internal
ethylene, etc.
[0049] Those of skill in the art will recognize that all pieces of
produce in a batch that is being analyzed for possible treatment
according to the methods of the invention may not be at the same
stage of ripening at the same time. Thus, when a term such a
"un-ripened fruit" is used, it may be used in the collective sense
in that, for example, most or a significant portion of the fruit in
a batch of interest is not ripe, e.g. at least about 10, 20, 30,
40, 50, 60, 70, 80, 90, or possibly 100% of the fruit meets the
criteria set forth herein as "not-ripened" or "partially" or
"fully" ripened, etc. as the case may be. In addition, those of
skill in the art will recognize that the criteria for determining
the stage of ripeness or maturation may differ from produce type to
produce type, or depending on the use or intended handling of the
produce type. For example, some apples are considered "ripe" or
"mature" or "ready to eat" or "ready to use" e.g. for cooking (at
least by consumers) when they are still very firm (e.g. crisp) and
tart, while other apples, or other fruits, are much sweeter and/or
softer when they are "ready".
[0050] With respect to vegetables and ornamental plants, the same
or similar procedures apply, i.e. glycine betaine may be applied at
any stage of development at which it is desired to arrest further
maturation and/or prevent senescence or spoilage of a plant or
plant product. The criteria for maturation or "readiness" for
vegetables and ornamental plants are known to those of skill in the
art and may be used to determine suitable times or stages for
application. For example, application may be pre-harvest when a
plant is still in the field, or post-harvest during storage or
shipment. Glycine betaine may be applied to leaves and/or to any
other accessible part of a plant, e.g. to portions of a plant such
as leaves, pea pods, ears of corn still in the husk, etc., or,
post-harvest to roots, peas that have been removed from pods, corn
that has been husked, etc., to name only a few illustrative
examples.
[0051] In some embodiments, glycine betaine is applied, usually by
commercial growers, as a liquid solution using methods that are
known to those of skill in the art, e.g. using known spray
apparatuses such as spray guns, various pressurized apparatuses,
etc._; or may be applied as a "fog" or aerosol e.g. within a
storage or shipping compartment; or by dipping or washing of the
produce; or by any other suitable means. However, it is not
necessary that liquid formulations be used. Glycine betaine may
also be applied as granules or as a "dust" using application
technologies that are known in the art. Such applications may or
may not be timed to coincide with other conditions such a weather,
e.g. application of granules or dusts may be carried out soon after
a rain or after application of another liquid (e.g. a liquid
pesticide) or during periods of high humidity, etc., so that the
granules/dust will readily adhere to the fruit (and liquefy, at
least to some extent) on the exterior of the fruit.
[0052] The application of glycine betaine may be carried out only
once, or may be repeated as needed or desired to maintain a desired
status of the produce. For example, an initial application may be
followed by subsequent applications at intervals of several days,
or weeks, or months, etc. as required to keep the produce in the
desired state. In addition, the application of glycine betaine may
be preceded, followed or alternated with the application of other
agents such as other anti-ripening, or anti-maturation agents; or
ripening or maturation agents may be applied to hasten the reversal
of the effects of glycine betaine. In general, the effects of a
single application of glycine have a duration as long as from about
5 to about 30 days, and may be as short as from about 1 to about 5
days.
[0053] In another embodiment of the invention, glycine betaine is
applied to produce or crops prior to harvest while they are "in the
field" (orchard, etc.) in order to protect the produce or crops
from environmental stress such as drought, excessive heat,
excessive cold, sun damage, etc. The application under these
circumstances is essentially the same as described above, but the
produce or crop is identified as being at risk of damage due to
untoward environmental conditions such a weather, e.g. lack of
rain, high temperatures, etc.
[0054] In another embodiment of the invention, glycine betaine is
applied to produce or crops prior to harvest while they are "in the
field" (orchard, etc.) in order to delay the abscission or fruit
drop of the produce. This application may occur one or multiple
times in a growing season.
[0055] In some embodiments of the invention, glycine betaine
preparations are prepared essentially for use by commercial growers
and/or entities which are involved in the storage or shipping of
produce. However, in other embodiments, the formulations are
marketed and sold directly to consumers, e.g. to a consumer who
wishes to delay the ripening or spoilage of fruit. Due to the known
safety of glycine betaine, provision of such preparations directly
to consumers does not pose a health risk, even if, for example,
directions supplied with the preparation are not followed
precisely, or if a solution of glycine betaine is spilled, consumed
by a pet, etc. For example, small-scale, sprayable liquid solutions
may be provided, and/or concentrated solutions or granules which
can be diluted or dissolved and applied by spraying or by other
means (e.g. as a fruit "wash") may be provided. This option may be
particularly appealing to consumers who like to buy produce ahead
of time (e.g. to take advantage of a sale, to buy produce during
peak season, etc.), and store it for a period of e.g. weeks or
months, or who grow and harvest their own fruits, vegetables,
flowers, etc.
[0056] In addition, "green" and/or "organic" and/or
"environmentally sensitive" products comprising glycine betaine may
be developed and marketed for use, for example, by growers,
suppliers, consumers, etc., especially since glycine betaine is a
natural by-product of other processes and thus its use can truly be
deemed efficient, not wasteful, etc.
EXAMPLES
Example 1
[0057] Research described in this Example shows that application of
a natural byproduct of molasses, glycine betaine, to d'Anjou pears
before harvest yields firmer pears compared to untreated pears
stored in the same post-harvest conditions (FIGS. 1 and 3).
Application increased the fruit firmness in a dose dependent
manner, with applications of 10 lbs/acre yielding the firmest
pears.
[0058] Glycine betaine treated pears also display a decrease in
soluble sugars measured in % BRIX in a dose dependent manner (FIGS.
2 and 3). Both firmness and % BRIX are used as an indicator of
fruit ripeness.
[0059] As time passes, however, glycine betaine treated pears
soften and exhibit increases in % BRIX, indicating that the effect
is temporary, and that ripening eventually occurs after
treatment.
[0060] While the invention has been described in terms of its
preferred embodiments, those skilled in the art will recognize that
the invention can be practiced with modification within the spirit
and scope of the appended claims. Accordingly, the present
invention should not be limited to the embodiments as described
above, but should further include all modifications and equivalents
thereof within the spirit and scope of the description provided
herein.
* * * * *
References