FR2889908A3 - Inhibiting fruit falling, particularly in apple and pear trees, comprises preparing and applying a solution and/or a suspension of 3,5,6-trichloro-2-pyridyloxyacetic acid and harvesting the fruits - Google Patents

Abstract

Process for inhibition of fruit falling, particularly in apple trees and pear trees, comprises: preparing a solution and/or a suspension of 3,5,6-trichloro-2-pyridyloxyacetic acid (I) or its alkyl ester or salt; applying (I) on the fruit trees and harvesting the fruits; and harvesting the fruits in which the application is carried out with in 1-5 weeks before the first harvest date.

Description

"METHOD OF INHIBITING FRUIT FALL"

  The present invention relates to a method of inhibiting fruit falling from fruit trees and using 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr), an alkyl ester or a salt of it, to inhibit the fall of the fruits.

  Triclopyr acid may be represented by the following formula: This substance is known to promote the natural fall (thinning) of fruits, such as mandarins or oranges, when their load is too high and the tree may produce fruit too small (see Japanese Patent No. 55/100307).

  Generally, it is known to apply 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr) to fruits of the citrus genus at a non-phytotoxic dose to regulate growth. In patent EP 0 659 048, 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr) is applied at the beginning of fruit growth, when the diameter of the fruit, for example lemons, does not exceed 28. mm.

  Such an application makes it possible to accelerate the growth of the fruit, to increase its size and to advance the harvest by about one month by an earlier maturation. The timing of the application of 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr) is crucial. In fact, if it is not appropriate, a thinning leading to a loss greater than 25% occurs or the purpose of this application is to improve the yield of fruit trees.

  None of the aforementioned documents allude to a regulation of fruit drop by inhibiting it.

  The fall of apples and pears during the 4 weeks before harvest can represent a considerable loss for producers. In certain windy regions or on certain varieties of fruits very sensitive to this phenomenon, the producer can lose up to 50% of his production. Once on the ground, fruits deteriorate rapidly and lose their commercial value.

  If it is desired to reduce losses in such conditions, it is desirable to carry out frequently repeated harvests, which represents a high labor cost and a heavy workload.

  The invention aims to overcome the drawbacks of the state of the art by allowing to delay the fall of the fruit, to reduce the number of harvests, without excessive loss, and therefore to lighten the workload of the pickers while reducing labor costs.

  To solve this problem, it is provided according to the invention, a method as indicated at the beginning comprising: E a preparation of a solution and / or suspension of 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr) ), an alkyl ester or a salt thereof, E at least one application at a non-phytotoxic dose of said solution to said fruit trees, and E at least one harvest of said fruits, said at least one application having from 1 to 5 weeks before a date corresponding to a first harvest in the absence of this at least one application.

  Indeed, and surprisingly, it has been found that the application of 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr), an alkyl ester or a salt thereof to a relatively short time to harvest without treatment, that is to say 1 to 5 weeks before it, allowed the fruit, especially apples and pears, to be delayed by a delayed effect on the peduncle of the fruit. ripe fruit. Therefore, the picking can be done by a more limited number of passages.

  As alkyl ester, it is advantageous to mention lower alkyl esters, and more particularly methyl, ethyl, n-propyl, and the like. As above-mentioned salts, mention may in particular be made of sodium, potassium, magnesium salt, etc. The solution or the suspension is to be carried out in any suitable liquid carrier in the field of agriculture, in particular in water.

  Advantageously, the application takes place, from 2 to 4 weeks, and more preferably around three weeks, before said date corresponding to a first harvest in the absence of this at least one application. This application period, at least for apples and pears, was determined as the period providing the best results.

  Advantageously, the application dose per ha is in the range from 3 to 50, preferably from 5 to 20 and more preferably from 10 to 15 grams of 3,5,6-trichloro-2-pyridyloxyacetic acid, alkyl ester and / or salt thereof.

  Therefore, the amount of 3,5,6-trichloro-2-pyridyloxyacetic acid, alkyl ester and / or salt thereof applied per hectare is less than the phytotoxic amount generally.

  In a particular embodiment, the concentration of 3,5,6-trichloro-2-pyridyloxyacetic acid, alkyl ester and / or salt thereof in said solution and / or suspension is in the range of 3 at 50 ppm, and is preferably about 20 ppm. This solution and / or suspension is applied to said fruit trees at a rate of 100 to 10,000 liters per hectare and preferably about 1000 liters / hectare. Moreover, this solution and / or suspension is advantageously applied by spraying a volume of slurry containing the active substance. This means of applying the substance in the liquid phase greatly simplifies the application.

  In a particularly advantageous manner, the process according to the invention further comprises, for said preparation of said solution and / or suspension, a compression of a mixture containing approximately 10% by weight of 3,5,6-trichloro acid. -2-pyridyloxyacetic acid, alkyl ester or salt thereof and 90% by weight of a binder with formation of an effervescent tablet to dissolve and / or disperse in water.

  It should be understood that such a formulation clearly simplifies the determination of the active substance in water. The tablet allows precise dosing in any condition. Indeed, it is very simple to add a predetermined number of tablets in the tank of a tractor to spray 1000 I on one hectare of orchard.

  The invention furthermore relates to the use of 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr), an alkyl ester or a salt thereof, for inhibiting fruit drop, to from fruit trees, in order to reduce the number of fruit harvests, and in particular from apple and pear trees, to reduce the number of apple and pear harvests.

  Other embodiments of the process and the use according to the invention are indicated in the appended claims.

  By the words "to inhibit the fall of the fruits", it is necessary to understand to delay the fall of the fruits in order to reduce the number of harvests. If the fruits stay longer on the tree, the threat of falling is reduced and it is not necessary to harvest them as often as when the fruit trees are not treated according to the invention.

  It should also be understood by "application taking place from 1 to 5 weeks before a date corresponding to a first harvest in the absence of this at least one application", that, when the fruit trees are not treated, one can presume a harvest date calculated as a function of time, flowering fruit trees, weather conditions, market gardening experience, etc. It is important to carry out the application of the solution and / or suspension according to the invention from 1 to 5, preferably from 2 to 4 and more preferably to around 3 weeks before this date which has been presumed, that is, that is to say before the date corresponding to a first harvest in the absence of this at least one application of triclopyr.

  This moment of application is crucial in order to avoid unwanted effects and to achieve the desired effectiveness.

  Other features, details and advantages of the invention will emerge from the description and examples given below, without limitation.

  In a series of trials with 3,5,6-trichloro-2-pyridyloxyacetic acid in different countries, a new and unexpected efficacy of the above-mentioned acid as an inhibitor of the fall of apples and pears been highlighted.

  To inhibit the fall of apples and pears during the weeks preceding harvest, 3,5,6-trichloro-2-pyridyloxyacetic acid is applied to fruit-bearing trees, which reduces the above-mentioned drop without causing any damage. damage to the tree.

  The preferred application technique is the spraying of a volume of slurry of the order of 100 to 10,000 liters / ha on all the fruit trees. The application rate is of the order of 3 to 50 grams of 3,5,6-trichloro-2-pyridyloxyacetic acid / ha. The time of application is 1 to 5 weeks before the presumed harvest. A preferred embodiment of the process comprises the application of 20 ppm of 3,5,6-trichloro-2-pyridyloxyacetic acid in water at a dose of 10001 / ha, on apple trees, 3 weeks before the date presumed harvest. Another preferred embodiment of the process comprises the application of 20 ppm of 3,5,6-trichloro-2-pyridyloxyacetic acid in water at a dose of 10001 / ha, on pears, 3 weeks before presumed harvest date.

  The preferred active substance is 3,5,6-trichloro-2-pyridyloxyacetic acid, however, lower alkyl esters and 3,5,6-trichloro-2-pyridyloxyacetic acid salts may also be advantageously used.

  The formulation recommended in the examples below is an effervescent tablet to dissolve and / or disperse in water, manufactured by compression of a mixture containing about 10% by weight of 3,5,6-trichloro-2-pyridyloxyacetic acid , an alkyl ester and / or a salt thereof and 90% by weight of a tablet binder.

EXAMPLES

EXAMPLE 1.-

  An efficacy trial was carried out in Belgium, in the region of SaintTrond (Vegi), under the following conditions: The crop tested is an orange Cox's (apple rootstock) crop. The test product is 3,5,6-trichloro-2-pyridyloxyacetic acid in 10% tablets, (10 gram tablets containing 1 gram of active substance), which was applied 4 weeks before the presumed harvest. Each plot consisted of 5 trees. The experiment was done in quadruplicate. The results are shown in Table 1 below.

Table I

  Tested dose (in tablets / ha) 0 6 10 20 Volume of slurry per ha (I) 300 300 300 300 Number of fallen fruits / tree at harvest 5.75 5.13 4.50 1, 88 Inhibition of fruit drop is good at 10 and 20 tablets per hectare. The high rate of 20 tablets / ha resulted in a ripe fruit harvest. The dose of 10 tablets / ha improved the red color of the fruits.

EXAMPLE 2

  An efficacy trial was carried out in Belgium, in the region of SaintTrond (Velm), under the following conditions: The culture tested is a Boskoop (Apple M9 rootstock) apple crop. The test product is 3,5,6-trichloro-2-pyridyloxyacetic acid in 10% tablets, (10 gram tablets containing 1 gram of active substance), which was applied 3 weeks before the presumed harvest. Each plot consisted of 5 trees. The experiment was done in quadruplicate. The results are shown in Table II below.

Table II

  Tested dose (in tablets / ha) 0 10 Volume of slurry per ha (I) 300 300 Number of fallen fruits / tree at harvest 5.50 1.38 One treatment per 10 tablets / ha, 3 weeks before harvest date presumed allows a significant decrease in fruit drop during the 5 weeks following treatment.

EXAMPLE 3

  An efficacy trial was carried out in France, in the Tour region, under the following conditions: The culture tested is a culture of Early Red One Erovan (M9 Emla rootstock) of apple trees. The test product is 3,5,6-trichloro-2-pyridyloxyacetic acid in 10% tablets, (10 gram tablets containing 1 gram of active substance), which was applied 3 weeks before the alleged harvest (the 28/08). Each plot consisted of 4 trees. The experiment was done in quadruplicate. The results are shown in Table III below.

Table III

  Tested dose (in tablets / ha) 0 10 20 30 Volume of porridge per ha (I) 1000 1000 1000 1000 Number of fallen fruits / tree on 17/09 14 10 7 12 Number of fallen fruits / tree on 24/09 22 11 4 3 Number of fallen fruits / tree on 29/09 20 14 9 4 Number of fallen fruits / tree total 56 35 20 19 3,5,6-Trichloro-2-pyridyloxyacetic acid has been shown to be effective against the fall of fruits, The dose effect is found. The quality of the fruits has not been modified (firmness, refractometric index and malic acid).

EXAMPLE 4.-

  An efficacy trial was carried out in Germany under the following conditions: The culture tested is a Burgemeister culture of pear. The test product is 3,5,6-trichloro-2-pyridyloxyacetic acid in 10% tablets, (10 gram tablets containing 1 gram of active substance), which was applied 3 weeks before the alleged harvest (the 15/08). The results are shown in Table IV below.

Table IV

  Dose tested (in tablets / ha) 0 6 10 20 Volume of porridge per ha (I) 1000 1000 1000 1000 Number of fallen fruits / parcel on 11/09 57 35 46 16 Number of fallen fruits / parcel on 23/09 83 44 30 24 Number of fallen fruits / plot in total 140 79 76 40 3,5,6-trichloro-2-pyridyloxyacetic acid has been shown to be effective against fruit drop, The dose effect is observed. The quality of the fruits has not been modified (firmness, refractometric index and malic acid).

  It is understood that the present invention is in no way limited to the embodiments described above and that many modifications can be made without departing from the scope of the appended claims.

  For example, it is possible to provide, for the preparation of the above-mentioned solution and / or suspension, the use of several salts or esters of triclopyr. It is also possible to consider adding, beside this inhibitor, one or the other active substance for another purpose.

Claims (8)

  A method of inhibiting fruit falling from fruit trees, particularly apple and pear trees, comprising: E preparing a solution and / or suspension of 3,5,6-trichloroacetic acid 2pyridyloxyacetic acid (triclopyr), an alkyl ester or a salt thereof, É at least one application at a non-phytotoxic dose of said solution on said fruit trees, and É at least one harvest of said fruits, said at least one application taking place from 1 to 5 weeks before a date corresponding to a first harvest in the absence of this at least one application.   2. A method of inhibiting fruit drop according to claim 1, wherein said at least one application takes place, preferably, from 2 to 4 weeks and more preferably around three weeks before said date.   A method of inhibiting fruit drop according to claim 1 or 2, wherein said at least one application is at a dose per hectare of 3,5,6-trichloro-2-pyridyloxyacetic acid, ester alkyl and / or salt thereof, preferably from 3 to 50 g / ha and more preferably from 5 to 20 g / ha and specifically from 10 to 15 g / ha.   A method of inhibiting fruit drop according to any one of the preceding claims, wherein said solution and / or suspension comprises from 3 to 50 ppm, and preferably about 20 ppm, of 3,5,6-trichloro acid. -2-pyridyloxyacetic acid, alkyl ester and / or salt thereof and is applied to said fruit trees at a rate of 100 to 10,000 liters per hectare and preferably about 1000 liters / hectare 5. A method of inhibiting fruit drop according to any one of the preceding claims, wherein said at least one application and / or solution of said solution and / or suspension is carried out by spraying.   A method of inhibiting fruit drop according to any one of the preceding claims, further comprising, for said preparation of said solution and / or suspension, a compression of a mixture containing about 10% by weight of acid 3,5,6-trichloro-2-pyridyloxyacetic acid, alkyl ester or salt thereof and 90% by weight of a binder with formation of an effervescent tablet to dissolve and / or disperse in water.   7. Use of 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr), an alkyl ester or a salt thereof to inhibit fruit drop from fruit trees, to reduce the number of fruit crops.   8. Use of 3,5,6-trichloro-2-pyridyloxyacetic acid (triclopyr), alkyl ester or salt thereof according to claim 7 for inhibiting fruit drop from apples and apples. pear trees to reduce the number of fruit crops.