A Method To Thin Flowers And Fruit
Field of the Invention
The present invention relates to a method of thinning of flowers and fruit in plants.
The present invention particularly relates to the thinning of a large variety of fruit plants using organosilicone surfactants.
The present invention more particularly relates to the thinning of "Orlah" fruit using surfactant.
Background of the Invention
The purpose of thinning fruit, whether it is done manually, chemically or mechanically, is to reduce crop load early in the fruit development period to maximize return of bloom (for apple) and ensure attainment of commercially acceptable fruit size (for peach, nectarine, plum, apple and table grapes). Although apples and grapes are routinely thinned in many districts, satisfactory results have not always been consistent, because sensitivity to any specific thinning agent varies from clone to clone, and climatic conditions enhance or diminish the efficiency of the chemicals. In peach and nectarines hand thinning is the main practical method that is currently employed, simply because none of the many chemicals and cultural practices employed, give consistent results. Among the many methods are: Control of flower buds initiation by gibberellic acid (M.Sc. Thesis, A. Breuer-Mizrahi, (1991) The Hebrew University of Jerusalem), flower thinners (R. Gaash, S. Lavee, A. Golan, D. Brown, "Alon Hanotea", (1969), pp. 319-325), fruitlet thinners (S. Morini, G. Nitagliano, C. Xiloyannis, J. Am. Soc. Hort.
ScL, 40, (1976), pp. 237-247, and G. E. Stembridge, C. G. Gambrell, Ibid., 96, (1971) pp. 7-9), urea, as well as cold water.
Two major problems are associated with these methods: Thinning intensity was inconsistent and difficult to control.
The broad range of effect makes it impossible to determine a precise developmental stage (of the flower or the fruitlet) for optimal treatment
In grapes, gibberellic acid is routinely used for thinning Thompson cultivar. The results, however, require always hand thinning for adjustment. The same treatment in
Perlette is not practiced for the last 15 years, since it was found that in this variety, the gibberellic acid causes irregular berry size (shotberries), therefore hand thinning is practiced in Perlette.
Obtaining benefit (eating, selling, trading) from fruit growing on trees within 3 years of planting in the orchard (Orlah) is not permitted according to the Torah (Leviticus 19:23). Currently, however, many orchards yield substantial amounts of fruit in the second or third year after planting. The yield of Orlah fruit in Israel in 1997 has reached some 3000 tons each of citrus and peach/nectarine and some 1000 tons each of apples and table grapes. There is an increasing awareness among observant Jewish consumers and the manufacturers of food products containing fruit for such members of the community in Israel and elsewhere, of the sheer tonnage of Orlah fruit that can potentially find its way to market.
Many growers have placed themselves under the supervision of kashrut organizations, so that they may market their fruit freely in all channels (especially to the military and to large institutions such as supermarket chains and hospitals). Such supervision requires that they remove Orlah fruits before the commercial harvest. Removal is usually done after fruit set or even well into the growing season, but the manual labor involved is expensive. There is a clear need for a reduction in labor costs via mechanization of the removal of Orlah fruits; one possibility is the use of sprays to prevent Orlah flowers from setting fruit.
Other objects of the invention will become apparent as the description proceeds.
Summary of the Invention
In accordance with the present invention there is provided a method for the thinning of flowers and fruit in plants, comprising applying an effective amount of the organosilicone known as "SILWET-408". The present invention results in the thinning of a large variety of fruit plants and in the case of Orlah fruit the almost total removal of said fruit from the plant.
Detailed Description of a Preferred Embodiment of the Invention "SILWET-408" is a Witco Company trade name for an organosilicone surfactant having the chemical name polyalkyleneoxyde modified heptamethylluroloxane, and has the following Chemical Abstract No. [67674-67-3].
The organosilicone "SILWET-408" is sprayed on the plants, flowers, and/or fruit in a concentration of 0.01% to 5.0%, preferably 0.08% to 1.5% for general thinning and in a concentration of from 0.01% to 5.0%, preferably 1.0% to 2.5% for thinning Orlah fruit.
The process of thinning was found to be effective on the following fruits: peaches, nectarines, apples, grapefruit, apricots, pommelo, almonds, lemon, oranges, and grapes.
The process of the present invention in regards to thinning is shown by one of three ways. The first way is that the time to thin using the process of the present invention is significantly less than in thinning by hand removal of the flowers/fruit. The second way is the extent of fruit-set, where the process of the present invention shows a significantly lower fruit-set (yield of fruit), compared to the control. The third way is by the measurement of the fruit weight (grams per fruit), where the process of the present invention should show a significantly increase weight per fruit - indicating thinning.
While the invention will now be described in connection with certain preferred embodiments in the following examples, it will be understood that it is not intended to limit the invention to these particular embodiments. On the contrary, it is intended to cover all alternatives, modifications and equivalents, as may be included within the scope of the invention as defined by the appended claims. Thus, the following examples, which include preferred embodiments, will serve to illustrate the practice of this invention, it being understood that the particulars shown are by way of example and for purposes of illustrative discussion of preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of procedures, as well as of the principles and conceptual aspects of the invention.
Examples
Example 1;
Flower thinning in Hermosa Peaches in 1996 using a back pack motorized mist blower sprayer. The results are the means of 5 replications.
Treatment Concentration Time Needed to thin No. of Applications
(min/tree)a "SILWET-408" 0.1% 14.2 ab 2
"SILWET-408" 0.08% 13.0 b 3
Unsprayed Control - 19.2 a
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 2;
Flower thinning in Babcock Peaches in 1996, as per Experiment 1.
Treatment Concentration Time Needed to thin No. of Applications
(min/tree)a
"SILWET-408" 0.1% 22.6 b 2
"SILWET-408" 0.08% 29.5 b 3
Unsprayed Control - 55.6 a
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 3;
Flower thinning in Hermosa Peaches in Maon, 1997, as per Experiment 1.
Treatment Concentration Percent Time Needed to No. of
Thinning3 thin (min/tree a Applications
"SILWET-408" 0.1% 75 a 25 b 3
"SILWET-408" 0.1% 71 a 28 ab 4
Unsprayed - 24 b 41 a
Control
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 4:
Flower thinning in Hermosa Peaches in Revivim, 1997, as per Experiment 1.
Treatment Concentration Time Needed to thin No. of Applications
(min/tree a
"SILWET-408" 0.1% 13 b 3 "SILWET-408" 0.1% 15 b 4 Unsprayed Control 29 a
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 5;
Flower thinning in Flavortop Nectarines in Maon, 1997, as per Experiment 1.
Treatment Concentration Percent Time Needed to No. of
Thinnin 3 thin (min/tree)3 Applications
"SILWET-408" 0.1% 73 ab 29 a 3
"SILWET-408" 0.1% 78 a 28 a 4
Unsprayed - 39 b 41 a
Control
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 6:
Flower thinning in Orit Apricots in Heletz, 1998, using high-pressure spray guns. The yield of each treatment (3 trees) were weighed.
Treatment Concentration Yield (Kg/Tree) No. of Applications
"SILWET-408" 0.1% 5.1 3
"SILWET-408" 0.25% 3.8 2
Unsprayed Control - 18.4
Example 7: Semi-Commercial fruit thinning of Flavortop Nectarines in Maon, 1998, using a commercial tractor powered mist blower sprayer.
Treatment Concentration Average Fruit/Size (5 No. of Applications rep / Gram/fruit)3 "SILWET-408" 0.1% 91 a 3
Unsprayed Control - 77 b
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 8:
Fruit thinning in Flavortop Nectarines in Maon, 1998, using high-pressure spray gun, averaging 5 trees per treatment.
Treatment Concentration Percei No. of Applications
"SILWET-408" 0.1% 78 a 3
"SILWET-408" 0.25% 72 a 2
"SILWET-408" 0.5% 78 a 1
Unsprayed Control - 49 b
3 Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 9:
Fruit thinning in Hermosa Peaches in Maon, 1998, as per Experiment 8.
Treatment Concentration Percent Fruit Weight No. of
Thinning3 (Grams/Fruit) 3 Applications
"SILWET-408" 0.1% 51 a 141 a 3
"SILWET-408" 0.25% 80 b 125 ab 2
"SILWET-408" 0.5% 46 a 120 b 1
Unsprayed - 43 a 114 b
Control
a Number in the same column followed by the same letter do not differ significantly at a probability of 0.05.
Example 10:
Semi-Commercial fruit thinning of Hermosa Peaches in Maon in 1998, as per Experiment 7.
Treatment Concentration Fruit Weight No. of Applications
(Gram Fruit) "SILWET-408" 0.1% 152
Unsprayed Control - 114
Example 11-23:
Removal of Orlah flowers in tree fruits.
"SILWET-408" (1%, v/v) was applied to wetness with a backpack 15-liter pressurized sprayer or with a hand-held 2-liter pressurized sprayer. All trees were in their third year of Orlah, except where noted. Unsprayed trees served as controls.
Stonefruit During the period 7-19.4.97, Hermosa peach and Flavortop nectarine trees were treated in the Binyamina area, while Hermosa peach and Honeygold, Francia, Flamekist, and Fairlane nectarines were sprayed in kibbutz Ein Zivan. Trees were at 75-90% of full bloom. Six trees per variety per treatment were sprayed in Binyamina, while four trees per treatment were sprayed in Ein Zivan. Fruit were counted four to five weeks after spraying.
Apples
On 5.5.97, Royal Gala, Smoothie, and Summer Red apple trees (five trees per variety per treatment) at 100% full bloom were sprayed at kibbutz Bar' am. Fruit were counted five weeks after spraying.
Citrus
In a preliminary experiment in January at the Nolcani Center in Bet Dagan, four branches on individual white grapefruit tees were sprayed to wetness with 1 and 2% "SILWET-408" in order to establish any phytotoxicity to citrus leaves. Branches were examined regularly for five weeks.
On 1.5.97, Murcott tangerine and white grapefruit trees were sprayed at Tze'elim at 90-100 of full bloom. Six trees of each variety were sprayed with each compound. Fruit were counted six weeks after spraying.
In all cases, fruit counts were made after natural thinning ('fruit drop') had taken place. All data are presented as number of fruits per tree. Means are separated by LSD at p=:5%, and, where relevant, by Duncan's test.
The results are given in four Tables, as follows:
Binyamina: Fruit Per Tree at 75-90% Bloom
Treatment Hermosa Peach Flavortop Nectarine
"SILWET-408" 0.7 b 0
Control 53 a 2.3
LSD 13.5
Ein Zivan: Fruit Per Tree at 75-90% Bloom (Nectarines)
Treatment Honeygold Francia Hermon Flamekist Fairlane Average "SILWET-408' 3.3 0.8 0.5 b 2.5 0 1.4 b Control 6.8 4.3 12.3 a 7.5 0.5 6.3 a LSD 4.7 3.5 7.9 13.4 - 3.2
Bar'am: Fruit per tree at 75-90% Bloom (Apples)
Treatment Roval Gold Smoothie Summer Red Average
"SILWET 408" 2.2 b 2.2 b 0.2 b 1.5 b
Control 11 a 17 a 16 a 14.7 a
LSD 5.9 7.3 7.9 3.6
Tze'elim: Fruit per Tree at Full Bloom
Treatment Murcott Tangerine White Grapefruit "SILWET 408' 3.2 b 1.3 Control 16 a 3.2 LSD 5% 12.1 3.9
Exa ple 24:
Orlah Fruit removal in Almonds (Napha & Umalfahum), 1998.
Fruit Set per Branch on 40-50 cm Branches. Average 10 Branches x 2 Trees
Treatment Concentration Napha Umalfahum
"SILWET-408" 0.5% 1.05 1.85
"SILWET-408" 1.0% 1.0 3.0
"SILWET-408" 1.5% 1.65 1.5
Unsprayed Control - 2.7 2.55
Example 25-33:
General: Materials and Methods
Sprays of "SILWET-408" generally were applied with a back-pack manual sprayer. In the semi-commercial trials, "SILWET-408" was applied with a 150-liter high-pressure gun-type sprayer or with a 1000 liter tractor-drawn sprayer. Although we intended to spray at 80% of full bloom, we were sometimes constrained to spray at a much earlier stage of bloom. Whole trees were sprayed, but flower and fruitlet counts were usually done on only on representative branches. Fruit set was determined from 6 to 8 weeks after spraying.
Experiments with the removal of Orlah Nectarines were carried out in kibbutz Rosh Zurim (RZ), Ramat Rachel (RR) and Ein Zivan (EZ) as well as in private orchards in the Binyamina area (BIN) and in Gimzo (on Orlah peach). The results were as follows:
Fantasia Nectarine Fairla ne Nectarine Flavortop Almog
Nectarine Peach
RZ EZ RR RZ EZ RR BIN EZ GIMZO
Control 18 27 47 14 31 39 49 13 41
"SILWEΓ-
408"
(0.25%) 13 20 - 9 - - - - -
(0.5%) 18 11 20 11 5 20 43 1.7 17
(0.75%) 13 - - 5 - - - - 20
- 15 24 - 3 10 25 0.5 -
The Percent Fruit Set and number of Fruits/tree in three types of Orlah apples were as follows:
Golden Delicious Red Delicious Galia Percent Fruit Set Percent Fruit Set No. Fruit
No. Fruits No. Fruits
Control 9.7 24 2 3.3 70
"SILWET-408" (0.5%) 7.5 21 0.6 1.3 68
"SILWET-408" (1.0%) 1.2 3 0.3 0.3 14
The effect of "SILWET-408" on number of Fruits/tree in Orlah lemon and pommelo trees was as follows:
Lemon Pommelo
Control 45 35
"SILWET-408" (0.5%) 21 2
"SILWET-408" (1.0%) 14 1.8