CA1122425A - Process for the manufacture of biologically active granules - Google Patents

Abstract

Abstract of the Disclosure:
Biologically active and abrasion-resistant pellets or granules are prepared by adding di- or polyisocyanates or the pre-polymers thereof and H-active compounds selected from the group of water and/or organic di- or poly(hydroxy-and/or amino) compounds or mixtures thereof capable of undergoing polycondensation to a mixture of carrier material and biologically active substance, granulating or pelleting the mixture obtained and allowing the pellets or granules to harden at a temperature in the range of from 10 to 60°C.

Description

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- 2 - HOE 77/F 195 It has been proposed to produce pesticides~contain-ing granules of different sizes with the use of natural mineral carriers or of carriers of vegetable origin. High polymeric natural substances and compounds on the basis of plastics materials have also been used for this purpose.
James ~. Polon has reported in Pesticide Formulations, edited by Wade Van Valkenburg, Marcel Dekker Inc. New York, pages 1~6 to 205, 1~73 about the technique of the produc-~ tion of granules from mineral carriers and their properties.
- 10 Attempts have been made to delay the release of the active substances by using high polymeric plastics materials instead of natural porous carriers. It has also been experimented to absorb pesticides on the aforesaid natural carrier materials of mineral or vegetable origin and then to envelope the products obtained with substances that are more or less soluble in water.
The said granules serve the purpose to absorb pesti-cidal agents, to deposit same and, after application, to release same more or less slo~ly to the surroundings. In this manner the active ingredients are able to act on animal or vegetable pests over a prolonged period of time.
The active ingredient can be released in different ways.
When it has a sufficient volatility and is bound only~
slightly to the carrier material, it can be set free by direct dif~usion. When, however, the active ingredienk is sparingly volatile and the carrier material is sufficiently hydrophilic, environmental moisture can wet the carrier material, penetrate into the said material and set free the 29 active substance.

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- 3 - HOE 77/F 195 F`inally, it is also possible to embed the active in-gredient in carrier materials that decompose slowly without and/or with external influence, whereby the effective substance is slowly set free. It is also possible, of course, to release the effective substance by any combi-nation of the described processes.
~ F-OS 2,238,912 describes polymer masses which can be decomposed by water and possess urea-like structures in their polymeric chain molecules, which masses can be liquld or solid. The liquid polymers may be transformed by a heat treatment into hard and brittle solids. These modifications are a result of molecule enlargement and cross-linking reactions. The biologically active substance can be elther incorporated lnto the polymer itself or it can be encap-sulated by the polymer. Owing to the necessary thermal treatment at elevated temperatures, the process is exclusi-vely limlted to those active substances that do not undergo any irreversible reaction with the ureas or pQSSi-ble additives under the specified conditions.
GB-PS 903,159 descrlbes the manufacture of pellets or small granules from a natural or synthetic wax, additives and a volatile insecticide (DDVP). After application, the insecticide is slowly set free and gets in the surroundings of the pests in gaseous form.
N1~-PS 6,909,123 relates to formulations using poly-ethylene wax having a molecular weight of about 2,000, a density of about 0.5 kg/l and a melting point of about 100 tQ 105Qc. In an autoclave an insecticide is added to the 29 molten wax at at temperature above its melting point.

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~ L~ HOE 77/F 195 After solidification of the wax, a formulation is obtained ~hich slowly releases the insecticide.
DE-OS 2,452,217 is concerned with the incorporation of organo-phosphorus insecticides into matrices on the basis of terpene-phenol resin. The resins having a soften ing point of at least 100C are obtained b~ reaction of different terpenes, for example dipentene, ~-pinene, - limonene and various turpentine fractions, with phenols in the presence of a condensation catalyst. In this manner the incorporated insecticide is protected against damaging external influences, for example humidity, and slowly released to the surroundings at a rate depending on the size of the active surface and other conditions.
The use of polyvinyl chloride, polyamide, polyur-ethane and other plastics materials in pesticidal formulations has been reported by N.Cardarelli, Controlled Release Pesticides Formulations, CRC Press Inc. 1976, pages 139 et seq.
G.B. Aquino and M.D. Pathak, J.Econ.Entom, 69, ~, page 6~6 (1976) describe experiments with insecticides in the cultivation of rlce. In this case insecticides are applied to the root region of rice plants in gelatin capsules or ln the form of simple granules ? in order to retard the release of the active substance to the plants. This ~ethod is very important in the cultivation of rice in view of the fact that during the peri.od of growth the rice plants must be continuously supplied with insecticides, which is done in conventiorlal manner by repeated spraying at about two weeks 29 intervals.

~2~5 The present invention provides a prQCess for the manufacture o~
biologically active pellets or granules which comprises the steps of adding to a ~uxture of a biologically active substance useful in agriculture and carrier material therefor an isocyanate material selected from diisocyanates, polyiso-cyanates and mixtures and prepolymers thereof and water, a polyhydric alcohol, a polyvalent amine or an alkanol am m e as an H-active co~ound reactive with said isocyanate material to form solid polyurethane-polyureas, compacting the resulting composition at high pressure into pressure resis-tant granules or pellets and thereafter causing said isocyanate material and H-active compound to react at a temperature of 10 to 60C to form a solid polyurethane-polyurea polymer, preferably 20 to S0C and more preferably at room temperature.
Suitable carrier materials in the process of the invention are all materials generally used in the ma~ufacture of granules, such as pre-fabricated and conminuted, solid, fully synthetic or partially synthetic organic high polymers/ materials of mineral, vegetable or animal origin, as well as inorganic; carriers. In order not to affect the solid quality, carrier materials of mineral or vegetable origin are preferred, especially those that stem from soil or rot easily.
As mineral or inorganic carrier materials there are mentioned by way of examples all types of silicic acid, diatomaceous earth, kieselguhr, silicates and silicate-containing substances such as clay, mica, pumice; chalk, magnesium carbonates, clays, sparingly soluble phosphates such as Thomas meal and all types of coal.
Suitable fully synthetic or partially synthetic organic high polymers are, for example, urea resinsr such as urea-formaldehyde resins, cellulose derivatives such as C

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cellulose ethers, polyvinyl alcohols or modified polyvinyl alcohols such as partially saponified polyvinyl acetates or propionates.
As carriers of vegetable origin there can be used in the first place saw dust, chipped straw from cereals, especially from corn and rice, peat and crushed corncobs.
The use of mineral and vegetable carriers has the advantage that they disintegrate or rot after use so that they do not constitute an additional burden to the envlronment, whereas some thermoplastic or duroplastic materials remain in the soil as foreign substances which cannot be degraded biologically. This fact i5 especially important in those cases in which for technical reasons the proportion of carrier material to active ingredient must be very high.
As biologically active materials there can be used soil-active compounds such as systemic insecticides, herbicides, fungicides, nematocides or algicides, as well as growth regulators and fertilizers or mixtures of the said biologically active substances. 'rhey can be used as such or dissolved in organic solvents, optionally with the addition of emulsifiers, wetting agents, hydrophobizing substances or - other ingredients known from formulation ~echniques. Biocides and growth regulators, which are not liquid at a temperature above 0C
and are sparingly soluble in water, are preferably used in organic solution. In analogy with the wetting powder technique, they are preferably added to the mixtures according to the invention in ad-sorhed form, advantageously on a highly active adsorbent.

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~ 7 ~ HQ~ 77~ 195 Suitable di- or polyisocyanates which undergo a poly-addition reactis3rl h~ith the H-active compounds to forn. a binding agent that hardens the pellets or granules are, ~or example, aliphatic, aromatic, heterocyclic, cylcoali-pnatic and araliphaic di- and polyisocyanates such as ethylene diisocyanate, 1,4~tetramethylene diisocyanate, hexamethylene diisocyanate, 1,12-dodecane-diisocyanate, 2,4 and 2,6-toluylene diisocyanate, diphenylmethane-2 and -4,~'-diisocyanate3 naphtahlene 1,5-diisocyanate;
chlorinated aryLpolyisocyanates, phenylene diisocyanates, diphenyl diisocyanates, xylylene-1,4-diisocyanate, toluene-2,4,6-triisocyanate, xylylene-1,4-diisocyanate, eyclohexy-lene-1,2- and -1,4-diisocyanate, 4,~',4"-triphenylmethane-triisocyanate, technical grade polymethylene pclyphenyl isoeyanate tPAPI(R)).
~ speeially good results are obkained with NCO pre-polymers from the aforesaid isocyanates, for example with di- or polyols of a mean moleeular weight of 5CO to 10,000. For the manufaeture of such pre-polymers there can be used, for examplet diols or polyols having from 3 to 6 hydroxyl groups per molecule or corresponding hydroxyl ; groups-containing polyesters, polyethers, polyester amides, polycarbonates and/or polyaeetals.
NCO pre-polymers are reaetion products of di- and polyisocyanates with diols or polyols or other eompounds eontaining a plurality of OH groups. The di- or- polyiso--eyanates are used in stoiehiometric excess so that the reaetion product3 formed still eontain a suf~icient number of ~ree NCO (isocyanate) groups that may reaet liixe 3~ po]yisoeyanates.

Z~Z5 - 8 - ~30E 77/F 195 The production of the isocyanate pre-polymers is des-cribed, for example by R.Viewe~, A.~ochtlen in Kunst~toff-~andbuch, volume VIl, Polyurethane, Carl Hanser Verlag, Munich 1966, pages 45 at seq.
A suitable H-active compound to be used as polycon-densation component for the specified isocyanates or their pre-polymers is in the first place, water, especially the water or moisture contained in the carrier materials. Fur-ther suitable polycondensation components are, for example polyhydric alcohols, polyvalent amines or alkanol amlnes.
Other reaction components for reactin~ with the NCO pre-polymers are high molecular weight polyols or polyamines, for example (poly)-hydroxy-polyethers, polyesters and poly-amides.
Suitable polyhydric alcohols are, for example, ethy-lene glycol, 1,2- and 1,3-propylene glycol, butylene glycol isomers, hexanediol, octanediol, 2-methyl-1,3-propanediol, glycerol, butanetriol, trimethylolpropane, hexanetriol, pentaerythritol, mannitol, sorbitol ? polyethylene glycols, polypropyleneglycols and polybutylene glycols.
emulsiflers, wetting agents, hydrophobizing substances or ~ ydroxylpolyesters that can be used are obtained by reacting polycarboxylic acids with polyhydric alcohols.
Suitable polycarboxylic acids are, inter alia, malonic acid, succinic acid 7 glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, isophthalic acid, and hexahydrophthalic anhydride. The specified polycarboxylic acids can be reacted with the polyhydric alcohols mention-ed above by way of examples.
Suitable poly~ster amides can be o~tained, f`or example, "

by reacting tile polyvalent, saturated and unsaturated carboxylic acids mentioned above or the anhydrides there~
of with polyvalent, saturated or unsaturated amino-alco-hols, diamines and polyamines.
Suitable polycarbonates can be prepared, for example, by reacting simple diols with diaryl carbonates or phos-gene.
Polyacetals to be used according to the invention may be prepared in known manner by reacting diols or polyols with formaldehyde.
Suitable amines as polyaddition components are also the following di- and polyamines: ethylenediamine, tri-methylenediamine, tetramethylenediamine, pentamethylene-diamine, hexamethylenediamine, diethylenediamine, tri-ethylenetetramine, tetraethylenepentamine, m-phenylene-diamine, p-phenylenediamine, piperazine, methylpiperazine, diethanolamine, diisopropanolamine and triethanolamine.
Depending on the chosen components, the aforesaid iso-cyanates react with the H-active compounds to polyurethanes, polyureas or polyurethane-ureas and thus form in situ the agent binding or holding together and/or embedding the individual particles of the carrier materials and the active ingredients. The polymerization speed can be ac-celerated in known manner by adding small amounts of basic amines, a]kyl tin compounds, alkali metal hydroxides, phe-no~.ates and/or alcoholates as catalysts. The proportions of the polymeri~ation components are chosen in known manner, preferably for one isocyanate group approximate]y one OH
29 or NH2 group should be available.

- 10 ~ HOE 77/F 195 The components of the mixtures according to the in-vention are in~en~ely mixed, in some cases advantageously with the addition of up to equal parts by weight of orga-nic solvents, calculated on the isocyanate component, and further processed on devices or machines known for granu-lation, pelletation or consolidatior..
The granules or pellets obtained are then stored for some time, for example several hours or several days, at room temperature or at higher temperature if a more rapid hardening is desired. The end of the hardening can be readily ascertained by determination of the coefficient of resistance. In general, hardening is complete after 1 to 5 days.
The composition of the granules or pellets can vary within wide limits. In general, their corltent of biocides and growth regulators is in the range of from 0.5 to 10 ~
; by weight, preferably 0.5 to 5 % by weight, calculated on the finished product, inclusive of 1 to 10 % by weight of an organic solvent, if any, and the required emulsifiers.
In the case of highly active compounds the proportion there-of can be reduced to 0.5 to 2 ~ by weight. The proportion the solid fertilizers, for example organic fertilizers, urea or mineral fertilizers, may be as high as 50 % and the fertilizer may partially replace the carrier rnaterial.
Thc proportion of binding agent consisting of a mix-ture of di- or polyisocyanate ol isocyanate prs-polymer and H-active compound is normally in the range of from 1 to 30 ~ by welg'lt, preferably 5 to 20 ~ by weight, rnore pre 29 ferably 6 to 12 % by weight. If necessary, the c~amponents ...... . . , ~ , . ~ ... . . . . . .

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~2Z425 of the binder are dissolved or suspended in ~p to equal parts by weight of an organic solvent. Suitable organic solvents are~ for example, those generally used in isocyanate chemistry. As regards the carrier material, the formulations generally contain about 30 to 70% by weight thereof, calculated on the granules ready for use.
Ihe process of the invention makes it possible to incorporate iTI granules or pellets of any desired size hyclrophobic as well as hydro-philic substances in such a manner that they migrate into the soil after a prolonged period of time only and are then taken up by the roots of the plants. Plant protecting agents having a limited stability in water may be additionally encapsulated in microcapsules before they are processed into pellets or granules. As embedding substances for the microcapsules, products are preferably used which ensure a slow release of the active compound or are slowly dissolved by water or the moisture in the soil and set free the active ingredient.
The process of the present invention offers, inter alia, the following advantages:
1) Several actLve ingredients can be applied in one working step.
2) The pellets or granules prepared by the process of the invention have a depot effect and, therefore, repeated applications accord-ing to conventional methods during the season can be dispensed with.
3) The plant is continuously supplied with the necessary active substance over a definite period of time.

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4) The active substances are utilized almost completely.
A possi~le polluting effect 011 the environment by ex-cess amounts of the active substance is avoided.

5) By the use of the aforsaid natural mineral and/or vege-table carrier materials minor amounts of foreign sub-stances only come into the soil, which may practically be neglected.

6~ With the use of the specified binders the fine-grained and soft mineral and vegetable carriers and active in-gredients are transformed into non dusting, abrasion-resistant pellets of a high mechanical strength which do not disintegrate, for example on the transport, dur-ing storage and application.

7~ The utilization of the moisture naturally contained in the formulation components for hardening (polycondensa-tion) makes it possible to produce completely dry gra nules and pellets.
;~ The following examples illustrate the invention but they are not intended to limit it thereto, since extensive variations of the substances and components to be used and ` the proportions thereof are possible. The seleckion of the individual substances depends on the desired properties of the granules or pellets to be made therefrom.
EXAMPLES OF PRRPARATION
E X A M P 1 E 1:
21 g of sa~ dust having a moisture content of 15 %
wer-e mixed with 20 g of kaolin and 70 g of urea (as ferti-lizer) and the mixture was grountl in a pinned disk mill 29 (type Condux C SI 150) to particles having a mean diameter k .
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of less than 500 microns. 0.5~ of castor oil oxethylate having l~O ethylene oxide units as emulsifier and 9.5 g of kieselguhr 12/0 were blended with a mixture of 2 g of 2-sec.butylphenyl-N methylcarbamate and 6 g of a mixture of saturated hydrocarbons having a boiling range of from 255 to 380C (Essobayol 90) and, after the addition of 10 g of` a toluylene-diisocyanate pre-polymer, prepared from toluylene diisocyanate, trimethylolpropane, butanediol and propylene glycol in a molar ratio of 8:3:1:1 in 12 g of xy-lene/ethyl glycol acetate (1.3), the mixture was blendedagain.
On a rotary pelleting machine operating under a pres-sure of 5,000 kg per die pellets having a weight of about 2 g and a diameter of 20 mm were produced from the mixture.
The pellets had reached their maximum resistance to pres-sure exceeding 15 kg/cm after a storage time of 2 to 3 days at room temperature. When the pellets were stored at about 50C, the same resistance to pressure was reached after 10 to 15 hours.

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In the manner described in Example 1, pellets having a weight of about 2 g and a diameter of 10 mm were produc-ed from the following components: 30 g of dry saw dust, 10 g of kaolin, 65 g of N-P-K mineral fertilizer 12:12:18, 5 g of ethylene glycol, 2 g of triazophos, 5 g of the hydrocar-bon mixture as used in Rxample 1, 1 g of castor oil oxethy-late with 40 ethylene oxide units, as emulsifier, 10 g of kieselguhr, 11 g of technical grade polymethylene poly ~ 29 phenylisocyanate (PAPI(R)) in 12 g of xylene/ethyl glycol ~ r~ k Z~L2~
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- 14 ~ HOE 77/F` 195 acetate (1:3). Af`ter a stora~e time of 2 days at room temperature ttle pellets had a maxirr~um resistance to preS
sure exceeding 15 k~/cm2. When the pellets were store-l at about 50C, the same resistance to prS~ssure co~lld be reached after 10 to l2 hours.
E X A ~i P L E 3:
In the manner described in Example 1, pellets having a diameter of 10 mm and a weight of 1 g were produced in an .- excenter press under a pressure of 5,000 k6 per die from 25 g of crushed corncobs, 40 g of dried aluminum oxide, 1 : g of 2-sec.butylphenyl-N-methylcarbarnate, 5 g of the hydrocarbon mixture as used in Example 1, 1 g of calcium isododecylbenzenesulfonate, 10 g of diatomaceous earth, 10 g of a prepolymer from toluylene diisocyanate and hexanetriol and 8 g of methylnaphthalene. After a storage time of 1 to 2 days at room temperature, the pellets had a maximum resistance to pressure over 15 kg/cm2.
E X A M P L E 4:
In the manner described in Example 3 pellets having a diarneter of 20 mm and a weight of 2 g were produced in an excenter press from 40 g of saw dust having a moisture con-tent of 20 %, 10 g of kaolin, 10 g of urea ~as fertilizer), 1 g of triazophos as microcapsules embedded in 1.5 g of carboxymethyl. cellulose, 8 g of the hydrocarbon mixture as used in Example 1, 1 g of calcium isododecylbenzene sul-fonate~ 10 ~ vf` diphenylmethane-4,4'-diisocyanate in 15 ~
of xylene/ethyl glycol acetate (1:3). After a storage time of 1 day at room temperature the maximum resistance to pres-29 sure of the pellets was found to be over 15 kg/cm2.

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- 15 - E30E 77/E_~95 E X A M P 1. ~ 5:
15 g of crushed corncobs, 45 g of kaolin, 1 g of pyrazophos, 4 g of commercial grade toluene, 1 g of castor : oil oxethylate with 36 ethylene oxide units as emulsifier, : 5 10 g of dia~omaceous earth, and 10 g of the pre~polymer as used in Example 1 in 10 g of xylene/ethyi glycol acetate 3) were mixed as described in Example 1 and from the mixture pellets having a diameter cf 20 mm and a weight of :about 2 g ~ere produced on an excenter press under a ~ressure of 5,000 kg per ~.ie~ After a storage time of 2 days at room temperature, the pellets had a maximum resistance to pressure of over 15 k~/cm .
E X A M P L E 6:
On a rotary peletting machine operating under a pres~
sure of 5,000 kg per die pellets having a weight of 2 g and a diameter of 20 mm were produced in the manner described .
in Example 1 from a mixture consisting of 30 g of dry sa~
~ust, 15 g of pumice, 40 g of N-P K mineral fertilizer 12-12-18, 4 g of hexamethylenediamine, 2 g of 2~sec.butylphe~
nyl~N-methylcarbamate, 6 g of technical grade xylene, 0.5 g of calcium isododecylbenzenesulfonate, 10 g of diatoma- :
ceous earth and 10 g of the pre-polymer specified in Example 1 in 12 æ of xylene/ethyl glycol acetate (1:3). After a storage time of 1 day at room temperature, the pellets had reached their maximum resistance to pressure of over 15 kg/
cm .

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BIOL.ûGICAL_X_MPLFS
_X A M P L E I:
Greenhouse tests To demonstrate the biological effect of the pellets 5 experirr.ents 1 and 2 were carried out in a greenhouse.
EXPERI~IENT 1:

_ . . _ . _ 6 week old rice plants and one pellet, prepared as described in Example 1 and corresponding to 25 mg of 2-sec.-butylphenyl-N-methylcarbamate as active ingredient, 10 were transplanted into containers. Each plant was infest-ed with 20 rice cicadas (Nilaparvata lugens) each 3, 7, 10, 14, 17, 21, 2LI, 28, 31, 35, 389 42 and 45 days after transplanting. Each time one dày after the respective inl`estation, the plants were controled. During the 15 experiment the test plants infested with the insects were kept at a tenmperature of +25C and a relative humidity of about 60 %. The results are summarized in Table 1.
infestation aftercontrol after % mortality (average .~ days days of` 3 repetitions) 7 8 `33 Il2 43 73 z~
- 17 - HOE '17/F 1g5 EXPERIMENT 2:
Under the conditi.ons of Experiment 1, the effect of pellets which had been prepared as described in Example 2 ; and contained 25 mg of triazophos as active substance per pellet was tested. The results are summarized in Table 2.

infestation aftercontrol after % mortality (a~erage - daysdays _ _ _ of 3 repetitions)_ ` 7 8 38 :~ 10 11 60 . 21 22 85 24 25 ~8 .`~ .
E X A M P L E II:
Fleld _tests On the basis of the test results obtained in the green-house according to Example 1,experirnents 3 and 4 were carried out in the open field with rice cicadas (Nilapar-~ata lugens). The pell.ets were given in one dose 3 days af~er transplantation of the young rice plants (3 DAT) and Z~

worked about 5 cm deep into the root region. The amount applied was 2.0 kg of active substance per hectare for 160,000 hills per hectare.
Under otherwise identical conditions, this corresponded in Exp0riments 3 and 4 to an amount of active ingredient of 12.5 Mg per pellet, pre-pared according to ~xa~les 1 and 2.
As comparative agent theTe was used in Experiments 3 and 4 commercial BPMC granules (Hopein* 4 G) containing 4 %
of 2-sec.-butylphenyl-N-methylcarbamate as active ingredient.
The first application of the granules was made as usual 12 days after transplantation ~12 DAT) with 1.0 kg of active ingredient per hectare, followed by thre0 further applica-tions at intervals of 15 days each, so ~hat a total amount of 4.0 kg o active ingredient was applied per hectare.
The plants were controlled 15, 19, 27, 30, 45, 71, 75, 79 and 86 days after transplantation (DAT). The results ; are summarized in Table 3 (experiment 3~ and in table 4 ~experiment 4).

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Claims (8)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for the manufacture of biologically active pellets or granules which comprises the steps of adding to a mixture of a biologically active substance useful in agriculture and carrier material therefor, an isocyanate material selected from diisocyanates, polyisocyanates and mixtures and prepolymers thereof and water, a polyhydric alcohol, a polyvalent amine or an alkanol amine as an H-active compound reactive with said isocyanate material to form solid polyurethane-polyureas, compacting the resulting composition at high pressure into pressure resistant granules or pellets and thereafter causing said isocyanate material and H-active compound to react at a temperature of 10 to 60°C to form a solid polyurethane-polyurea polymer.

2. The process of claim 1, wherein the granules or pellets are allowed to harden at a temperature of from 20 to 50°C.

3. The process of claim 1, wherein the granules or pellets are allowed to harden at room temperature.

4. Granules or pellets composed of a solid polyurethane-polyurea polymer, a biologically active substance useful in agriculture and a carrier material therefor, produced by the process of claim 1.

5. Method of combating pests which comprises applying to the infested plants or soil an effective amount of pellets or granules as claimed in claim 4 and containing a pesticide as biologically active substance.

6. Method of combating pests in rice fields, which comprises using an effective amount of granules or pellets as claimed in claim 4 and containing a pesticide as biologically active substance.

7. Method of fertilizing which comprises using an effective amount of granules or pellets produced according to claim 1, in which the biologically active substance is a fertilizer.

8. Methods of combating pests and fertilizing which comprises using an effective amount of granules or pellets produced according to claim 1 containingas biologically active substance a mixture of plant protecting agents and a fertilizer.