How to chemically control garlic diseases

I. Growing period

(1) To control garlic rust, in years with abundant rainfall, check the disease foci promptly in early spring and carry out timely prevention. Generally use 15 percent Fenxiuning wettable powder at 1000 times dilution, or 15 percent Fenxiuning wettable powder at 1500 times dilution plus 70 percent mancozeb wettable powder at 1000 times dilution for the first control in early April, then control once more after 10 to 15 days, generally controlling 2 to 3 times depending on the severity of the disease.

(2) To control garlic leaf blight, leaf spot, gray mold, etc., use 75 percent chlorothalonil wettable powder at 800 times dilution, or 64 percent sandofan wettable powder at 500 times dilution, or 50 percent copper succinate-glutarate wettable powder at 500 times dilution, or 50 percent iprodione wettable powder at 1500 times dilution. Begin control in late November or late March depending on the field disease situation, and apply 2 treatments in spring.

(3) To control viral diseases, using virus-free garlic gives the best control effect; field plants are strong with dark leaf color, and generally no spraying is needed. Secondarily, in the early stage of disease, spray 1.5 percent Zhibingling at 1000 times dilution, or 5 percent Junduqing at 300 times dilution.

(4) To control bacterial soft rot, in the early stage of disease spray leaves with 72 percent agricultural streptomycin soluble powder at 4000 times dilution, or 77 percent Keshade wettable fine granule at 500 to 800 times dilution, about once every 7 days, and apply 2 to 3 consecutive treatments depending on the disease situation.

II. After harvest and during storage

This mainly involves controlling storage-period diseases such as blue mold, gray mold and purple blotch. At present the following measures are mainly adopted:

(1) Stop irrigation 5 days before harvest to prevent the garlic skin from rotting and becoming unsuitable for storage.

(2) During harvest, avoid mechanical damage as much as possible, promptly clear away diseased plant residues, carry them out of the field, and compost them in a concentrated high-temperature pile or waterlogged compost, which helps reduce sources of disease and lower the chance of disease occurrence.

(3) The harvested garlic should be dried in the sun promptly, peeled according to commercial garlic requirements, and rotten garlic, green garlic, etc. should be picked out.

(4) For cold-storage preservation, after entering the warehouse, fumigate and disinfect with "Lüda" brand fruit and vegetable smoke agent, which can effectively control further damage to garlic bulbs from late-stage and storage diseases.