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Tests with two grades of winter-oil emulsion differing in percentage content of paraffinic hydrocarbons showed that the grade with the higher content possessed the better ovicidal properties. This result was confirmed in field trials. Orchard Trials (a) Fungicides: Control of Brown-rot of Peaches. —Best results were secured with dichloronaphthoquinone. Applications at blossoming of 1 lb. to 2 lb. to 100 gallons increased crop yield, while pre-harvest sprays not only protected fruit up to the picking stage but resulted in less disease development in storage. On Golden Queen, and to a lesser extent on Paragon, pre-harvest sprays caused grey blemishes on the skin. (b) Fungicides: Control of Black-syot of Apples.—Sprays based on phenyl mercury ammonium lactate and phenyl mercury chloride gave better control and caused less foliage injury than the standard sulphur sprays. Ferric dimethyldithiocarbamate and tetramethylthiuram disulphide gave control equal to or better than standard spray; they were slightly less efficient than the mercury sprays but caused less foliage damage. With the above four test materials, appearance of fruit was better than that from standard sprays, except in one case where mercury sprays retarded development of fruit colour. (c) Fungicides: Control Brown-spot and Grease-spot of Passionfruit. — Further trials on control of brown-spot and grease-spot of passionfruit have shown that Cuprox at 3 lb. to 5 lb. per 100 gallons is less efficient than Bordeaux mixture (3-4-50). Cuprox caused considerable damage to vines, retarding growth and reducing yield of fruit. Insecticides. —Trials with dichlorodiethyldichlorethane (DDD) on apples have shown it to give highly effective control of leaf-roller. Treatments applied in the early summer have been shown to be of major importance in control of this pest. Use of DDD has given a marked increase in woolly-aphis populations as compared with DDT, observations suggesting that use of the former had resulted in a greater reduction in the population of the parasite Aphelinus mali. Gamma isomer of benzene hexachloride (BHC) has given outstanding control of woolly-aphis. Winter applications on apples of wettable powders at dilutions equivalent to 5 oz. to 10 oz. gamma isomer to 100 gallons have kept trees virtually clean for the whole summer. Applications during the summer of 4 oz. gamma isomer to 100 gallons have also given control, but in all cases tainting of fruit occurred. Where, in place of the crude benzene hexachloride used in the above trials, 95 per cent, pure gamma isomer has been employed in preparing sprays, tainting of fruit appears to be eliminated. In experiments for control of red-mite, Selocide, Arathane, parathion and tetraethyl pyrophosphate (TEP) have been compared as summer sprays. Selocide has given highly efficient results. Both Arathane and parathion applied immediately after the blossom period gave control up to mid-summer, after which severe infestations developed. TEP killed adult and nymph stages, but re-infestation rapidly developed. Vegetable Field Trials Fungicides.—Various fungicides have been tested for control of late-blight on tomatoes. Treatments with copper oxychloride plus the adhesive polyethylene polysulphide gave better control than copper oxychloride alone. Bordeaux mixture still remains the most effective fungicide. On beans for control of

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