AU739143B2 - Process for the preparation of rice seed for sowing - Google Patents

Description

-v 4 S F Ref: 382548

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant: Rhone-Poulenc Agrochlmie 14-20 rue Pierre Baizet 69009 Lyon

FRANCE

Actual Inventor(s): Michael Glenn Redlich Address for Service: Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Invention Title: Process for the Preparation of Rice Seed for Sowing The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845

I-

-1- PROCESS FOR THE PREPARATION OF RICE SEED FOR SOWING The present invention relates to a new process for the preparation of rice seed for sowing and new improved rice seed obtainable by the process.

It is known to improve rice seed by treating such seed by means of plant growth regulators such as gibberellic acid so as to get stronger and better plants, better and stronger germination and thus obtain better growing and cropping conditions. Furthermore, planted rice seed or the rice crops therefrom are also attacked by a number of pests or can suffer predation by birds. Another problem 10 associated with rice cropping is the displacement of said rice plants upon flooding rice fields, a common agricultural practice.

i" A useful method of protecting rice and rice seed and rice crop is to apply one "or more phytoprotection products to the seed by different methods such as coating, soaking or dipping. Said seed can be dry seed or soaked seed or pregerminated 15 soaked seed. Although it is well-known that dry or ungerminated seeds can be coated with a phytoprotection product and subsequently sown, a common practice is :to pregerminate rice seed by soaking the seed in water containing one or more phytoprotection products followed by a period in which the soaked, treated seed is allowed to drain and produce a radicle. (The period during which the seed is soaked, 20 drained and during which a radicle is produced is called the pregermination period and the resulting composition, that is, a seed from which a radicle has been produced before it is sown, is a pregerminated seed.) This is a most efficient and attractive way of seed treatment, but there remains the problem of the disposal of hazardous waste water despite efforts to minimize the concentration of the phytoprotection product or the volume of the liquid. Another potential hazard of this conventional seed soaking method is the generation of seeds that are treated but unused for any reason. Said unused seeds can be hazardous waste.

Rice seeds are commonly sown by dropping pregerminated seeds from an airplane over a flooded rice propagation area. Webster et al., in the publication -2- Hilgardia, 1973, vol. 41, pages 689-698, indicate that sowing pregerminated rice seed in such a manner "introduces complications not experienced with seed treatments in other cereals." The authors further recommend treating rice seeds with a phytoprotection product either before soaking said rice seeds or during the soaking process. Nonetheless, when these seed treatment methods are utilized with the required volumes of seed, very large volumes of hazardous liquid waste can be generated.

International Patent Publication No. WO 93/1705 describes a process in which pregerminated seed can be coated by a foam and one or more phytoprotection compositions. However, said publication is silent about rice seed and about the S•growth conditions of the pregerminated seed. In addition, the aforementioned problem of unused, treated seed is not obviated. Webster et al., vide supra, describe treating pregerminated seed with the fungicides Captan, Captofol, or Thiram after the soaking process and obtaining no increase in plant stand, no advantage.

15 An object of the instant invention is to still further improve the rice seed, rice germination, rice plant, rice plant growing and rice plant cropping.

Another object of the instant invention is to provide an improved method of rice cultivation.

Another object of the instant invention is to provide a method of having 20 stronger rice seedlings or plants which have a better resistance to wind and rain.

Another object of the instant invention is to provide an improved process for the preparation of rice seed for sowing.

Another object of the instant invention is to provide a new seed which is designed for sowing by plane.

Another object of the instant invention is to provide a highly effective method of preparing rice seeds for sowing by plane.

Another object of the instant invention is to provide a process for the preparation of rice seed for sowing in large quantities that reduces or minimizes or even avoids altogether the generation of hazardous, unusable seed.

17. AUG. 2001 14:52 SPRUSON FERGUSON NO. 5183 P. Another objcti of thle itntinlvtl'ti~l i-S to pr'ovide a process for tile PrepaLration o1, ricQ seed for sm~inio that redUCesO ii ie rCei .isth rIinlo1lqi wvaste.

Another object of thc inlstant( inventio is to minim111izC thle exposure of humanlls to phytoprotection products.

Another object of thle instant inventionl is to provide a rapid Method for- the treatment of rice seed by a phytoprotection product.

Another object of thle instant invention ik to provide a method of* protection of rice Seed againist Insect pecsts which Is effective over a substantial period of time.

U) Another object of the instanlt inivention is to provide a Method of protectionl Of rice seed which avoids the disadvantages of the known methods.

These and other objects will better appear dUrig the descri ption of the invention. It is the aimn of the instant invention to achieve at least one of the stated obJects.

A First aspect of the instant invention IS al ne0W seI Which is a progeriminuted ri1ce sced comprising a coating which coating comprises a) piln gr'IowthrII L atr prefcrahly a gibberellin, more preferably gibberellic acid.

Another aspect of the invention is related to pregcrrninated rice seed comprising a coating, which coating comprises a plan( growth regulator (preferably a gibbereli in, more preferably gibberellic acid), said seed having a radicle size such that said radicle is nu0t 20 substantially damnaged by the seed treatment process. Practically speaking, said seed generally has a radicle size from about 0. 1 to about 15 mil, preferably from about 0.5 to about 10 mm, even more preferably from about I to about 5 mm.

There is also provided by the present invention a method of preparation of rice seed of the first aspect comprising the following step)s: pregerininating said seed in water containing substantially no phytoprotcction product or plant growth regulator a( a temperature and 6or a period of timle sufficient to produce a radicle having a size such that said radcle is not substantially dalmaged Inl It subsequent seed treatment process; and [R:NL1fZZ12873.dm:nak mixing the pregerminated seed with an effective amount of plant growth regulator (preferably a gibberellin, more preferably gibberellic acid).

A preferred embodiment of the invention is one in which the amount of said pregerminated seed is appropriate for sowing from the air, usually in quantities from about 10 to about 20000 kg, more preferably from about 100 to about 1500 kg.

Said pregermination process is preferably effected in one or more bags. Bags are water permeable containers that are optionally deformable, preferably able to contain from about 10 to about 1000 kg of seed before soaking. Sowing from the air generally entails the loading of an aircraft, preferably an airplane, followed by flying 10 over the field to be sown and distributing the seed to be sown. Another type of aircraft suitable for sowing is a helicopter.

:i The plant growth regulator which can be used in the instant invention is preferably: used as a composition comprising an effective amount of plant growth regulator, preferably a gibberellin, more preferably gibberellic acid, which optionally 15 further comprises one or more phytoprotection products.

The plant growth regulator can be used in the present invention together with a phytoprotection product as defined hereinafter.

The seed as hereinabove described is usually brought into contact with the plant growth regulator by mixing. The mixing of said seed with a plant growth 20 regulator generally takes place at or near within about 50 kilometers of) an airport or airstrip, preferably within the legal boundaries of an airport used by said planes for sowing. Said mixing can optionally take place in a mixing apparatus that is in or on a truck, trailer, or other movable device suitable for transporting said mixing apparatus. Said seed to be pregerminated and mixed with a plant growth regulator may also be transported by crane or forklift or hopper mechanism at each stage. Another contemplated mode of transportation of the seed at each or any stage of the method of the invention is by use of an auger.

The plant growth regulator which is used to coat the rice seed is preferably a liquid composition, which may be aqueous or non-aqueous, in order to improve the speed of application. It may be fairly diverse in nature and is defined in practice so i as to be able to ensure the coating upon the seed of the required effective amount of active material. It is preferably other than a gel. The formulation used in the invention can be, for example, a solution, suspension, emulsion, suspoemulsion (that is to say, an emulsion which is simultaneously a suspension), powder dissolved or suspended in liquid, or the like. The viscosity of this liquid composition is preferably less than about 500 centipoises. The formulation used in the invention thus comprises, as necessary constituents, the active material(s) and solvent(s), usually water; it optionally and additionally contains other customary constituents used in agrochemical formulations, for example those described in International 10 Patent Publications No. WO 87/03781, 93/06089 and 94/21606 as well as in European Patent Publication No. 0295117 and United States Patent No. 5,232,940.

:i Among the compositions which can be used in the invention, it is preferable g to choose those which are more suited to rice seed coating. For example, sticking agents such as low molecular weight polymer, e.g. latex polymer formulations, often effectively promote sticking of the plant growth regulating material or phytoprotection product upon the seed. The aqueous formulations used in the invention may also comprise another non-aqueous liquid phase.

By the term "phytoprotection product" is meant a material which may be used to provide an effective protection of rice seeds from pests attacks. The 20 phytoprotection products that are particularly preferred are those that provide protection of the said seeds and plants derived from such seeds from insect attacks, particularly rice water weevil, as well as from fungal attacks, in which case the phytoprotection product comprises an insecticidally active compound or fungicidally active compound, respectively. The phytoprotection products which may be used according to the present invention may also be such materials as biocontrol agents, that is, biological substances (typically, substances comprising fungi, bacteria or viruses) that protect seeds and plants derived from such seeds from insect and fungal attacks and/or provide nutrients to said seeds or plants derived from said seeds.

Another type of phytoprotection product contemplated by the invention comprises the class of macronutrients and micronutrients, that is, substances that function as a plant food.

By the term "plant growth regulator" is meant any substance or product or composition or compound that promotes plant or root growth, or both, as understood by those skilled in the art of plant growth regulating effects. The known effects of gibberellic acid are typical of plant growth regulating effects as meant in the present specification.

The term "effective amount" as used herein means an amount of the plant growth regulator or phytoprotection product sufficient to produce the desired 10 response; for example, in the case of the plant growth regulator, an effective plant growth regulating amount; in the case of an insecticide, an insecticidally effective amount; in the case of a fungicide, a fungicidally effective amount, etc.

o According to a particularly preferred feature of the invention, the time from the end of the pregermination period to the mixing of the pregerminated seed with 15 the plant growth regulator is less than about twenty-four hours, preferably less than about eight hours. In another feature of the invention, the time from the end of the pregermination period to the sowing of the seed is less than about forty-eight hours, preferably less than about twenty-four hours, even more preferably less than about eight hours.

20 According to another feature of the invention, the pregermination of the rice seed is preferably provoked or activated during a period of time from about half a 'day to five days, preferably during a period from one day to three days.

According to a further and important feature of the invention, the seed is treated with a plant growth regulator comprising gibberellic acid and an insecticidally active ingredient. This ratio (insecticidally active ingredient gibberellin; w/w) is generally from about 10/1 to about 1000/1, preferably from about 20/1 to about 200/1. The ratio of the insecticidally active ingredient to gibberellic acid depends upon the specific insecticidally active ingredient which is used.

-7- In a particularly preferred aspect of the invention, the insecticidally active ingredient is selected from the group consisting of: -[(6-chloro-3-pyridyl)methyl]-N 2-cyano-Nl-methylacetamidine (acetamiprid); 1 6 -chloro-3-pyridylmethyl)-N-nitroimidazoidin-2-ylideneanine (imidacloprid); 2 ,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate (carbofuran); 0,0-diethyl O-3,5,6-trichloro-2-pyridiyl phosphorothioate (chiorpyrifos); 1 4 -chlorophenyl)-3-(2,6-difluorobenzoyl)urea (diflubenzuron); a pyrethroid such as (S)-cz-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)-3methylbutyrate (esfenvalerate); [1 x(S 3 cx(Z)]-(±)-cyano(3-phenoxyphenyl)methy1 3-(2-chloro-3 ,3 ,3trifluoro- 1-propenyl)- 2 2 -dimethylcyclopropanecarboxylate (lambda-cyhalothrin); an insecticidal 1-aryl pyrazole; an insecticidal 1-aryl pyrrole; and an insecticidal 1-aryl imidazole.

The 1-arylpyrazoles which can be used according to the instant invention are preferably compounds of formula R R,

N

wherein: R I is CN or methyl;

R

2 is S(O)nR-; -8-

R

3 is alkyl or haloalkyl;

R

4 is selected from the group consisting of hydrogen, halogen, -NR 5

R

6

-C(O)OR

7 -S(O)mR 7 alkyl, haloalkyl, -ORg, -N=C(R 9

)(R

10 and -C(O)alkyl;

R

5 and R 6 are independently selected from a hydrogen atom, alkyl, haloalkyl, -C(O)alkyl, -C(O)OR7, -S(O)rCF3; or R 5 and R 6 form together a divalent alkylene radical which may be interrupted by one or more heteroatoms, preferably selected from oxygen, nitrogen and sulfur;

R

7 is selected from alkyl and haloalkyl;

R

8 is selected from alkyl, haloalkyl and hydrogen; 10 R 9 is selected from hydrogen and alkyl;

R

10 is selected from phenyl or heteroaryl each of which is unsubstituted or substituted by one or more hydroxy, halogen, -O-alkyl, -S-alkyl, cyano, or alkyl or combinations thereof; X is selected from nitrogen and -C-R 12 R1 1 and R 12 are independently selected from halogen or hydrogen;

R

13 is selected from halogen, haloalkyl, haloalkoxy, -S(O)qCF3, -SF 5 m, n, q, r are independently selected from 0, 1, and 2; provided that when R 1 is methyl, R 3 is haloalkyl, R 4 is NH 2

R

1 1 is Cl, R 13 is CF 3 and X is N.

The alkyl and alkoxy groups and moieties thereof of the formula are preferably lower alkyl and alkoxy groups, that is, groups having one to six carbon atoms. The haloalkyl and haloalkoxy groups likewise preferably have one to four carbon atoms. The haloalkyl and haloalkoxy groups can bear one or more halogen atoms; preferred groups of this type include -CF 3 and -OCF 3 It shall be understood that the ring formed by the divalent alkylene radical represented by R 5 and R 6 and including the nitrogen atom to which R 5 and R 6 are attached is generally a 5, 6, or 7-membered ring. When Rio is heteroaryl, it is preferably pyridyl, most preferably 2- -9pyridyl. It will be understood that the 1-arylpyrazoles of formula include enantiomers and/or diastereomers thereof.

A preferred group of 1-arylpyrazoles for use in the present invention are those of formula with one or more of the following features wherein:

R

1 is CN;

R

4 is -NR 5

R

6

R

5 and R 6 are independently selected from the hydrogen atom, alkyl, haloalkyl, C(O)alkyl, C(O)OR 7 X is C-R 12 or .10 R 13 is selected from a halogen atom, haloalkyl, haloalkoxy, and

SF

5 Another preferred group of 1-arylpyrazoles of formula for use in the present invention is that wherein:

R

1 is CN;

R

3 is a haloalkyl radical; R4 is NH 2 X is C-R 12 R11 and R 12 represent, independently of one another, a halogen atom; and

R

13 is a haloalkyl radical.

A most preferred compound of formula for use herein is 5-amino-1-(2,6dichloro- 4 -trifluoromethylphenyl)-4-trifluoromethylsulfinyl-3-cyanopyrazole, hereafter designated as Compound A.

Compounds of formula may be prepared according to known processes, for example as described in International Patent Publications No. WO 87/03781, 93/06089, and 94/21606 as well as in European Patent Publications No. 0295117, 0403300, 0385809 and 0679650, German Patent Publication No. 19511269 and United States Patents No. 5,232,940 and 5,236,938.

Representative fungicides that may be used in the method of the invention include the following: 1,2-ethanediylbis [carbamodithioato] manganese mixture with ethanediylbis [carbamodithioato] zinc (mancozeb); methyl 1 -(butylcarbamoyl)benzimidazol-2-ylcarbamate (benomyl); 3-(3 ,5-dichlorophenyl)-N-( 1-isopropyl)-2,4-dioxoim idazolidine- 1carboxamide (iprodione); ethyl hydrogen phosphonate (fosetyl); ethyl hydrogen phosphonate aluminum salt (fosetyl-aluminum); *.10 tetramethylthiuram. disulfide (thirarn); [2-(2,4-dichlorophenyl)-4-propyl- 1 ,3-dioxolan-2-yl]methyl- 1 H-i ,2,4triazole (propiconazole); -(4-chlorobenzylidene)-2,2-dimethyl- 1 H-I ,2,4-triazol- 1 ylmethyl)cyclopentanol (triticonazole); 5 ,6-dihydro-2-methyl- 1,4-oxathiin-3-carboxanilide (carboxin); methyl N-(2-methoxyacetyl)-N-(2,6-xylyl)-DL-alaninate (metalaxyl); methyl. (2-1j6-(2-cyanophenoxy)pyriniidin-4-yloxylphenyl 1-3methoxyacrylate (azoxystrobin);or a copper fungicide, such as but not limited to dicopper chloride trihydroxide.

Representative biocontrol agents that may be used in the method of the invention include: Bacillus thuringiensis; Bacillus subtilis; Pseudomonas spp.; Rhizobium spp.; Azospirillum spp.; or Beauveria spp.

Micronutrients and macronutrients that may be used according to the invention include: i- -11iron chelates; zinc chelates; manganese chelates; or nitrogen.

The gibberellins are a known group of plant growth regulators which has been described in inter alia, The Pesticide Manual, 10th edition, (1994), The British Crop Protection Council, London. Gibberellic acid is a member of this group.

According to a feature the invention, phytoprotection products may be mixed with the seed separately, together or in any by known methods for those skilled in 10 the art of the application of phytoprotection products, in addition of course to the plant growth regulator.

The amount of pesticidally active, preferably insecticidally active, material may depend of the particular pesticide or insecticide being used. Generally, the amount of active ingredient which is applied to the pregerminated seed is from about 15 2 to about 1000 g/q. (gram of active ingredient per quintal of germinated seed), preferably (especially for the 1-aryl pyrazoles or imidacloprid) from about 5 to about 800 still more preferably from about 5 to about 100 g/q.

According to a further embodiment of the invention, there is now provided a new composition of matter which is a dry pregerminated seed rice comprising on its 20 surface a plant growth regulating agent, preferably a gibberellin, and more preferably gibberellic acid, and optionally a pesticidally active ingredient such an insecticidally active ingredient. The dry seed may be dry only at the outside part of the seed; some humidity may be present in the inner part of the seed. This dry germinated seed has a radicle whose size is generally from about 0.1 mm to about 15 mm, preferably from about 0.5 to about 10 mm.

The amount of plant growth regulating agent, preferably of gibberellic acid, laid upon the seed is generally from about 0.01 to about 50 g/q. (gram of active ingredient per quintal of pregerminated seed), preferably (especially for gibberellic acid) from about 0.1 to about 5 still more preferably from about 0.3 to about 3 g/q.

J

Ir -12- In the various methods or processes for treating rice seeds, as defined above, the amount of formulation brought directly into contact with the seed (or propagation material) to be treated is generally from about 0.1% to about 20%, preferably from about 0.5 to about 1.5 of the weight of seeds to be treated. Values outside these ranges, whether more or less, can also be used but without substantial or specific advantage.

The invention further relates to a process for cultivating and/or growing rice in which the germinated rice seed, as hereinabove defined, for example coated with a composition comprising an effective dose of plant growth regulating agent, and ,o *10 optionally of pesticidally active ingredient, is sown. The said process is such that, for a long subsequent period after germination, preferably for the rest of the growing season, it does not comprise any other treatment (either of the seed or of the plant •resulting therefrom) to protect the plants against the same pests, e.g. insects (that is to say, no other pesticidal, e.g. insecticidal, treatment). This means that the °15 effectiveness of the process according to the instant invention is sufficient to eliminate the need for another insecticide treatment altogether.

The invention also relates to a mass, or collection, of germinated (or, in other words, pre-germinated) rice seeds, in which the seeds are in the form of grains which have already germinated (in other words, these seeds have already their first radicle), 20 and are at the same time covered or coated bathed in or sprayed on) with a oo°°o S•formulation as defined above and containing a plant growth regulating agent, and optionally a phytoprotection product (preferably an insecticide) as herein described, especially those of formula The improved seeds of the invention, when germinated and grown, generally have a bigger shoot and a bigger root than untreated seeds. Known rice seeds treated by gibberellic acid usually had a bigger shoot, but not a bigger root than the untreated seed. According to a feature of the invention the seeds are such that the radicle and the shoot are generally the same length. Furthermore, the improved seeds of the invention are more resistant to being uprooted or displaced by wind after sowing, especially 2 or 3 days or more after sowing. This advantage exists even if the seed is not in a deep location in the soil. Another advantage to this method is that said seeds are less likely to be eaten by birds since a sown rice field can be quickly flooded to prevent such eating. Another advantage of the instant invention is that, since the rice plants resulting from the said seed treatment are more quickly and firmly established, herbicides can be applied earlier before any weeds get large, thus contributing to the efficacy of the herbicides.

In another important aspect of the invention, there is now provided a composition comprising a plant growth regulator and an phytoprotection product selected from an insecticidal 1-arylpyrazole, an insecticidal 1-arylpyrrole or an 10 insecticidal 1-arylimidazole, preferably an insecticidal 1-arylpyrazole of formula R2 R

R**

4

N

R

R1**

R

13 o I wherein:

R

1 is CN or methyl;

R

2 is S(O)nR3;

R

3 is alkyl or haloalkyl;

R

4 is selected from the group consisting of hydrogen, halogen, -NR 5

R

6

-C(O)OR

7 -S(O)mR 7 alkyl, haloalkyl, -ORg, -N=C(R 9

)(R

10 and -C(O)alkyl;

R

5 and R 6 are independently selected from a hydrogen atom, alkyl, haloalkyl, -C(O)alkyl, -C(O)OR 7 -S(O)rCF3; or R 5 and R 6 form together a divalent alkylene radical which may be interrupted by one or more heteroatoms, preferably selected from oxygen, nitrogen and sulfur; -14-

R

7 is selected from alkyl and haloalkyl;

R

8 is selected from alkyl, haloalkyl and hydrogen;

R

9 is selected from hydrogen and alkyl;

R

10 is selected from phenyl or heteroaryl each of which is unsubstituted or substituted by one or more hydroxy, halogen, -O-alkyl, -S-alkyl, cyano, or alkyl or combinations thereof; X is selected from nitrogen and -C-R 12 R11 and R 12 are independently selected from halogen or hydrogen;

R

13 is selected from halogen, haloalkyl, haloalkoxy, -S(O)qCF3, -SF 5 m, n, q, r are independently selected from 0, 1, and 2; provided that when R 1 is methyl, R 3 is haloalkyl, R 4 is NH 2

R

1 1 is Cl, R 13 is CF 3 and X is N.

.*e Even more preferably in the composition, the plant growth regulator is a gibberellin, preferably gibberellic acid and the insecticidal 1-arylpyrazole is 15 amino- 1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethylsulfinyl-3cyanopyrazole.

The following examples are descriptive, and are not to be taken as limiting examples. Other choices of materials, methods, and organisms may be chosen by those skilled in the art in light of the teaching herein.

EXAMPLE 1 Rice seeds (227 kg) were soaked at 25 °C in water for 24 hours. The seed was removed from water and allowed to drain for 30 hours. The seeds were allowed to absorb excess water, and were allowed to germinate up to the point of having emerging radicles whose size was between 1 and 8 mm.

These seeds were treated by thorough machine mixing with a latex polymer formulation containing about 0.2% w/v of gibberellic acid. The thus-obtained germinated seeds appeared undamaged and had a coating comprising gibberellic acid.

Seed was sown by plane in a flooded field. After a period of time of 3 to days, it was observed that the shoots had about the same size as the shoots obtained with classical treatment of rice seed with gibberellic acid; however, the root and the shoot were of approximately the same size, contrary to the size obtained with classical treatment of rice seed with gibberellic acid (in which the root is smaller); the seedlings were highly resistant to wind even though they were located in the soil at a depth as small as 0 to 2 mm (less deep than that formed with classical treatment of rice seed with gibberellic acid).

EXAMPLE 2 The procedure of Example 1 was repeated except that the pregerminated seeds were coated with the same treatment of gibberellic acid as in Example 1 and with mancozeb in a slurry at a rate of 19-22 fluid ounces (570-630 mL) per hundred pounds (45 kg) of seed.

Seeds were then sown by plane onto a flooded field where the same .observations were made as in Example 1.

EXAMPLE 3 The procedure of Example 1 is repeated, except that the latex polymer formulation containing about 0.2% w/v gibberellic acid further contains about 3% w/v of Compound A. Seeds are then sown by plane onto a flooded field.

Claims (5)

17.AUG-2001 14:53 SPRUSON FERGUSON NO. 5183 P. 11 Ice, The claims defining the invention are as f'ollows: A pregel-minated IecC seed comprising a1 coating, which coaCil iscs a plant growth regulator. 2. A pregen-ninated rice seed according to claim i. whereill the plangr,1owNtlh Lregulator is a gibberellin. 3. A pregeuinated f ice seed accord'ing to claim 1, wherein the plain growth reaulator is gibbercilic acid. 4. A pregei-minaled rice seed according to ally one of the foregoing claims, he1rein the radicle size is in thie range of from about 0.1 to about 15 mm. A p~rge mi naed ice seed acco ding 10 ally one of claims 1 to 3, whurein the radicle size is in the range of from 0.5 to [0 mm. A pregeirninated rice seed according to any one of the foregoing claims wheein .he radicle and the shoot are generally the same length. 7. A pregern-inated rice seed according to any onle of the foregoing claims further comprising a phytoprotcctioi 1 Iloduct. S. A pregerminated rice seed according to claimii 7, wherein the phyloprotectioll product comprises an insecticidally active ingredient, fungicidally active ingredient, illicronutrient or macronutnent. 9. A pregerminated rice seed according to claim 7 or 8, wherein the phytoprotection product is selected from acetaniprid, imidacloprid, carbofurain chlorpyrifos, diflubenzuron, esfenvaleratc, lambda-cyiablollthiin an insecticidal I-aryl pyrazole, an insecticidal I-aryl pyrrole, an insecticidal I-aryl imidazole, nancozeb, Sbenomyl, iprodone, fosetyl, fosetyl-aluninum, thiram, propiconazole, ti ticonazoc, carboxin, netalaxyl, azoxyslrobin, a copper fungicide, Bacillus thluringiensiv, Bacillus Siilhs, l'sCef(lonif /sppJ.. R/ujzobiltm spp., 'lz-ospirilzm spp., fleallveria sflf). anl ir'on clclatc, a zinc chelale, and a manganese chelatc. A pregcninated rice seed according to claim 9, wherein llhe insecticidal I arylpyrl'zule is aI compotind of the flormula: R2 RR R 4 N R11 R13 [R:\LIBZZJo27 doc:saak 17.AUG.2001 14:53 SPRUSON FERGUSON NO.5183 P. 12 17 vhcrei n: Ri is o- ll(hyl: R, ls S(O) 1 lZ1; R 3 is alkyl or fialoalkyl; R 4 is selected froom the group conlsisting or hydrogen, halogn, -NR 5 R 6 -C(O)0R 7 alkyl, haloalkyl, -OR 8 -N=C(R 9 and -C(O)alkyl; R 5 and are independently selected from a hydrogen atom, alk l, haloalkyl -C(O)alkyl, -C(O)OR 7 -8(O)rCF 3 or R; and R 1 form together a divalent alkylene radical which may be interi-rupted by one or more hteroatoms 11) R 7 is selected from alkyl and haloulkyl; R 8 is selected from alkyl, haloalkyl and hydrogen; R 9 is selected from hydrogen and alkyl; Rio isselected from lhenyl or heteroaryl each of which is Pnsubstitutcd or substituted by one or miore hydroxy, halogen, -0-alkyl, -S-lylI, cyano, or alkyl or Iw colihi nations thcreolf X is selected f-om nitrogen and -C-R12; R 1 1 and R 1 2 are independently selected from halogen or hydrogen; R 1 3 is selected from halogen haloalkyl, haloalkoxy, -S(O)qCF 3 -SF; III I, q, r are independently selected from 0, 1, and 2; provided that when R, is I'dll, R3 is haloalkyl, R4 is NH2, Rii is Cl, Ri' is CF.; and X is N. 11. A pregerminagd rice seed according to claimi 10, wherein the heteroatoms in the definition of Rs and R 6 are selected from oxygen, nitrogen and sulfur. 12- A pregerminated rice seed acco-ding to claim 10, wherein the I-arylpyrazole of frula has one or more ofthe following features: R 1 is CN; 14 is-NRjR,; K 5 and( are independenctly sclccted from the hydrogen atom, alkyl. haloalkyl, C(O)alkyl, CNO)0R 7 X is C-R 12 or R 1 1 is selected from a halogen atomn, haloalkyl, hialoalkoxy, anld -81%. 13. A pregerminated i-ice seed according to claim 10 or claim 12, wherein the compound of formula is 5-amino-I -(2,6-dichloro-4-trifluoromethylphenyl)-4 trifiuoromethylsulfinyl-3-eyanopyrazole. LRAUlDZZ]02873.doc:sak 17. AUG. 2001 14:53 SPRUSON FERGUSON NO.5183 P. 13 s18 14. A method oF preparation of rice seed according to claim 1, comprising the following steps: pregerminating said seed in water containing substantially no phytoprotection product or plant growth reglulator at a tcmperature and For a period of S time sufficient to produce a radicle having a size such that said radicle is not substantially damaged in a subsequent seed treatment process; and mixing the pregerminated seed thus obtained with an efe6tive amount of plant growth regulator. IS. A method according to claim 14, wherein said pregerminated seed is treated iu in step by mixing with a cumposition comprising the plant growth regulator and a phytoprotectioll product. *16. A method according to claim 15, wherein the phytoprotection product is selected from acetamiprid, imidacloprid, carbofuran, chlorpyrifos, diflubezurolln csfenvalerate, lambda-cyhalothrin, an insecticidal I -aryl pyrazole, an insecticidal I 1-aryl is pyrrole, an insecticidal 1-aryl imidazole, mancozcb, benomyl, iprodione, fosetyl, Fosetyl- aluminumn, thiram, propiconazole, triticonazole, carboxin, metalaxyl, azoxystrobin, a copper fungicide, Bacillus thuringiensis, Bacillus subtilis, Pseudomonas. spp., Rhizobium spp., Azospirillun spp., Beauveria spp., an iron chelate, a zinc chelate and a manganese 2 chclate. 9 o 17. A method according to claim 15 or claim 16, wherein the pesticidally active ingredient is a 1-aryl pyrazole as derfined in claim 10 or imidacloprid.

18. A composition comprising a plant growth regulator and an insecticidal I- arylpyrazole, an insecticidal 1-arylpyrrole, or an insecticidal 1-arylimidazole when used in a method according to claim 14. 2 19. A composition according to claim 18, wherein -the insecticidal I -arylpyrazole is as defined in claim A composition according to claim 18 or claim 19, wherein the plant growth regulator is gibberellic acid and the insecticidal I -arylpyrazole is 5-arnino-l-(2,6-dichloro- 4-trill uoromethylphenyl)-4-tri fluoromethylsulfi nyl-3-cyanopyrazole.

21. A pregerminated rice seed, substantially as hercinbefore described with reference to any one of the Examples. [R\LJRZZ02873.doc:ank 17. AUG. 2001 14:53 SPRUSON FERGUSON NO. 5183 P. 14 19

22. A method of' prepiaration of rice scedI according to claiml 1, thle moth~lod substaihlly as hereinbelbre descibed with rcfi-encc to any one oF i e Exanlples'

23.~ Z A rgriac ice seed pr-epar-ed acco-diz tn the method of any one of claims 14 to 1 7 and 22. Dated 17 August, 2001 Rhone-Poulenc Agrochimie Patent Attorneys for the Applicant/Norninated Person SPRUSON FERGUSON lR:\I.113Z]J02873.dcc:aak