Synergistic insecticidal compositions
This is a division of Ser. No. 08/459,196, filed Jun. 2, 1995, now U.S. Pat. No. 5,534,543 which is a division of application Ser. No. 08/199,233, filed Feb. 22, 1994, now U.S. Pat. No. 5,491,168. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention is directed to mixtures of propargite and synthetic pyrethroids, which exhibit synergistic activity as pesticides. 
     Thrips palmi is a transplanted insect from Southeast Asia which has caused serious damage to cucumber, watermelon, melon, eggplant and green pepper in recent years. It has no strong natural enemy, and is believed to cause more serious growth damage or fruit damage than any other known insect. Compounds such as sulbrophos, oxamil, carbosulphane, cypermethrin, pemfracalp, BMPC, DMTP, cyfulbenzron, etc. have been used in the past. However, none of them has had a sufficient protective effect. 
     SUMMARY OF THE INVENTION 
     The compositions of the present invention contain an active ingredient comprising a mixture of A) propargite, and B) a synthetic pyrethroid. The present invention also comprises a method for controlling undesirable insects which comprises applying an effective amount of a composition according to the present invention to a locus to be protected. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The propargite portion of the active ingredient is a well known insecticide sold under the trademark OMITE (Uniroyal Chemical Company) and has the chemical name 2-(4-tert-butylphenoxy) cyclohexyl prop-2-ynyl sulfite. Examples of the synthetic pyrethroid active ingredient are cyfluthrin, fenpropathrin, cyhalothrin, fluvalinate, tralomethrin, etofenprox, flucytirinate, cypermethrin, permethrin, and fenvalelate. 
     In the insecticide compositions of the present invention, the propargite component may be present in the amount of from 3 to 1,000 ppm, or more preferably 100-400 ppm. The synthetic pyrethroide type component may be present in the amount of from 1 to 1,000 ppm, or more preferably 10-200 ppm. 
     Propargite, which is one of the effective components of the insecticide offered by the present invention, shows almost no effect against minami-kiiro-azamiuma (also known as Thrips palmi) by itself. In addition, synthetic pyrethroide type insecticides, which is also one of the effective components of the insecticide compounds offered by the present invention, does not show sufficient effect against minami-kiiro-azamiuma by itself even in the case of cypermethrin which has obtained the Agricultural Chemical Registration in Japan. The compositions offered by the present invention give superior effectiveness which cannot be obtained by each component alone. 
     As it is described in the application example, common forms of agricultural agents such as aqueous solutions, emulsions, dry-flowable, flowable, or smoke agent which contain the propargite and the synthetic pyrethroide type insecticides may be prepared. Alternately, agents which contain the individual active ingredients are prepared and then mixed together later. 
    
    
     The present invention is explained in detail by reference to the following examples. 
     EXAMPLE 1 
     
         ______________________________________                                    
Propargite               30 parts                                         
Tralomethrin              1 part                                          
White Carbon (Silica)     2 parts                                         
Diatmaceous Earth        58 parts                                         
Alkylbenzene sodium sulfonate                                             
                          2 parts                                         
Lignin sodium sulfonate   7 parts                                         
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     The above components were uniformly mixed, and dissolved in water to obtain a 31% aqueous solution. 
     EXAMPLE 2 
     
         ______________________________________                                    
Propargite               30 parts                                         
Tralomethrin              1 part                                          
Xylene                   44 parts                                         
Dimethylformamide        15 parts                                         
Alkylbenzone calcium sulfonate                                            
                          4 parts                                         
Polyoxyethylene-alkylphenylether                                          
                          6 parts                                         
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     The above components were mixed and melted to obtain a 31% emulsion. 
     EXAMPLE 3 
     A mixed aqueous solution of propargite (BPPS) and synthetic pyrethroid type insecticides was diluted to the concentrations shown in Table 1, and sprayed on individually potted 20-30 am tall greenhouse grown eggplants (kind: Kokuyo) which were severely infested by minami-kiiro-azamiuma by using a portable sprayer until the liquid started to drip from the leaves. The number of adult and larvae of minami-kiiro-azamiuma were counted before the spraying and a few days after the spraying, and its effectiveness compared with the effectiveness obtained by spraying them individually. The results are shown in Table 1. 
     
                                           TABLE 1                                 
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                    Number of Insects/4 leaves.sup.1)                     
            Concentration                                                 
                    O DAT.sup.2)                                          
                          4 DAT 7 DAT 11 DAT                              
Treatment.sup.3)                                                          
            (ppm)   A. L..sup.4)                                          
                          A. L. A. L. A. L.                               
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Control (No Treatment)                                                    
            --      59  79                                                
                          93 136                                          
                                152                                       
                                   183                                    
                                      104                                 
                                         626                              
Propargite (Pro.)                                                         
            400     48  80                                                
                          130                                             
                             76 176                                       
                                   212                                    
                                      106                                 
                                         546                              
Pro. + Tralomethrin                                                       
            400 + 10                                                      
                    28 179                                                
                           0  0  0  0  1  0                               
Tralomethrin                                                              
             10     31 108                                                
                          17 71 59 123                                    
                                      44 64                               
Pro. + Cypermethrin                                                       
            400 + 60                                                      
                    80 138                                                
                           0  0  0  0  6  0                               
Cypermethrin                                                              
             60     17 169                                                
                           7 31 16  57                                    
                                      49 46                               
Pro. + Cyhalothrin                                                        
            400 + 25                                                      
                    42 160                                                
                           0  0  0  0 12  0                               
Cyhalothrin  25     26 132                                                
                          35 153                                          
                                69 185                                    
                                      39 65                               
Pro. + Permethrin                                                         
             400 + 100                                                    
                    25 188                                                
                           6 12  9  16                                    
                                      10  4                               
Permethrin  100     42 138                                                
                          19 118                                          
                                32 183                                    
                                      41 51                               
Pro. + Fluvalinate                                                        
            400 + 50                                                      
                    12 206                                                
                          15 10  1  2 15  0                               
Fluvalinate  50     45  91                                                
                          58 196                                          
                                57 224                                    
                                      111                                 
                                         161                              
Pro + Fenpropathrin                                                       
             400 + 100                                                    
                    27 259                                                
                          11 15  2  9  6  4                               
Fenpropathrin                                                             
            100     22  86                                                
                          33 180                                          
                                70 130                                    
                                      57 52                               
Pro. + Etofenprox                                                         
             400 + 200                                                    
                    18  94                                                
                           9  3  4  10                                    
                                       9 12                               
Etofenprox  200     33  70                                                
                          56 71 62 244                                    
                                      77 131                              
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 .sup.1) 2 marked leaves/pot                                              
 .sup.2) DAT = Days after treatment                                       
 .sup.3) Sprayed on May 27, 1991                                          
 .sup.4) A. = Adults L. = Larvae                                          
 
    
     
                                           TABLE 2                                 
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                    Number of Insects/4 leaves.sup.1)                     
            Concentration                                                 
                    O DAT.sup.2)                                          
                          4 DAT 7 DAT 11 DAT                              
Treatment.sup.3)                                                          
            (ppm)   A. L..sup.4)                                          
                          A. L. A. L. A. L.                               
__________________________________________________________________________
Control (No Treatment)                                                    
            --      28 38 57 82 55 91 43 87                               
Propargite (Pro.)                                                         
            400     28 38 19 37 15 46 33 72                               
Pro. + Tralomethrin                                                       
            400 + 10                                                      
                    35 70  0  0  1  1  6  5                               
Tralomethrin                                                              
            10      19 57 11 42 19 69 44 41                               
Pro. + Cypermethrin                                                       
            400 + 60                                                      
                    60 102                                                
                           0  0  3  4  2  1                               
Cypermethrin                                                              
            60      16 24  9 36 29 28 55 20                               
Pro. + Cyhalothrin                                                        
             400 + 100                                                    
                    34 62  0  0  0  1  2  0                               
Cyhalothrin 100     18 45 11 56 21 58 18 34                               
Pro. + Cyfluthrin                                                         
            400 + 25                                                      
                    47 86  0  0  4  0  8  1                               
Cyfluthrin  25      27 97  8 28 35 104                                    
                                      45 17                               
Pro. + Fluvalinate                                                        
            400 + 50                                                      
                    40 91  0  1  4  7  8  4                               
Fluvalinate 50      43 72 29 94 36 80 32 83                               
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 .sup.1) 2 marked leaves/pot                                              
 .sup.2) DAT = Days after treatment                                       
 .sup.3) Sprayed on May 27, 1991                                          
 .sup.4) A. = Adults L. = Larvae                                          
 
    
     EXAMPLE 4 
     The effect of propargite (BPPS) and synthetic pyrethroid mixtures on minami-kiiro-azaiuma was studied in a manner similar to Example 3, except that the emulsion form of Example 2 was used. The results are shown in Table 2.