Crop protection, antibiotic

Antibiotics are substances produced by microorganisms that inhibit growth of plant diseases in very dilute concentrations. Cycloheximide, actidione, and streptomycin are the most diffuse antibiotics available for crop protection. Streptomycin is used as dust. 

Dichloroacetic acid, CHCI2-COOH, is produced by hydrolyzing dichloroacetyi chloride, which is obtained by the oxydation of trichloroethane. Dichloroacetic acid and its derivatives (esters) are intermediates in organic synthesis for pharmaceuticals, antibiotics and crop protection agents. 

But wait. Let s remember that chemicals have virtually transformed the modern world in extraordinarily beneficial ways. During the past 100 years the chemical industry has offered up, and we have eagerly consumed, thousands of highly useful materials and products. Among these products are many that have had profoundly beneficial effects on human health - antibiotics and other remarkable medicinal agents to prevent and cure diseases, pesticides to protect crops, preservatives to protect the food supply, plastics, fibers, metals and hundreds of other materials that have enhanced the safety and pleasures of modern... 

Remark Biopesticides are used elsewhere, as well. Certain bacteria can be sprayed on strawberries and other fruit crops to protect them against late frosts. Other bacteria, fungi, and yeasts are used to control diseases of stored fruits. Beneficial bacteria, called probiotics, can be fed to humans and animals to relieve the symptoms of diseases and maladies. Probiotics can produce useful biochemicals (such as vitamin K in the human gut), attack harmful viruses and bacteria through natural antibiotics, and crowd out harmful microbes. Competitive exclusion is a powerful weapon that has only begun to be used to advantage. 

Kasugamycin has been developed as a specific and effective antibiotic to control rice blast since 1965. The antibiotic controls the disease when applied at 20 ppm in aqueous solution and shows both protective and curative activity [20]. Kasugamycin has been used to control rice blast on a large scale. In practice, the antibiotic is predominantly used as a dust at 0.3% of the active ingredient. In addition, seed treatment with 2% wettable powder of kasugamycin protects rice plants against blast for one month. The antibiotic exhibits a high crop safety no phytotoxicity has been observed. 

In the 19 th century chemistry was viewed as the central discipline around which physics and biology gravitated. The medical revolution with the synthesis of drugs and antibiotics coupled with the development of chemicals protecting crops and the expansion of organic chemistry in every aspect of life increased the life expectancy from 47 years in 1900 to 75 years in the 1990s and to over 80 years in 2007. 

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