Pesticides in Rural Prosperity: Perceptions and Ground Realities (Part 1)

Plant diseases are known since time immemorial. Epiphytotics of certain diseases such as Late Blight of potato in Ireland in 1845, Coffee Rust in 1875 in Sri Lanka, Bengal famine in 1942 in India, are some of them which caused untold miseries and changed the history of mankind. Plant pests are responsible for approx 40 percent reduction in yield worldwide (Oerke et al., 1994). As per Assocham Study, India is losing annually INR 50,000 crore due to various pests and diseases (TNN/Feb 14, 2014), excluding annual post-harvest losses amounting to INR 2.5 lac crore, in addition to spoilage  of  21 million tonnes of wheat – equivalent to entire production of Australia (PTI, Jan 10, 2013) due to poor storage infra-structure. Pesticides have been successfully used worldwide since 19th century (Pimental et al 1967; Home and Page, 2000) for plant protection and public health. I earnestly believe that they shall be used in future also as most effective arsenal against plant pests in view of development of relatively safer and eco-friendly fungicides. Pesticides came under serious criticism with the publication of Silent Spring in 1962 by Rachel Carson, who apprehended threat to mankind and environment... Frank Graham (1970) too held similar view on pesticides in his book ‘Since Silent Spring’. Another publication, ‘Silent Spring Revisited’ by American Chemical Society (1987) also corroborates the views of Rachel Carson. However discovery of pesticides due to scarcity of food led to development of wide range of pesticides without taking cognizance of her revelation.

Today we have specific fungicides which can control, downy mildew, powdery mildew and a variety of diseases as listed in the Table 1.  Bordeaux mixture, copper oxychloride, Sulphur discovered in 19th century still hold the ground. Discovery of dithiocarbamates as potent fungicides marked the beginning of second generation fungicides, which include very widely used fungicides like zineb and mancozeb. The other important fungicides considered to be part of 2nd generation are captan, captafol, dinocap etc. The first systemic fungicide carboxin and oxycarboxin made their debut in 1966 and marked the beginning of third generation fungicide. Carbendazim, a benzimdazole fungicide appeared two years later. Subsequently phenylamides, and fosetyl-Al aimed at controlling Oomycetous fungi were discovered. In spite of outbursts against pesticides by Rachel Carson in 1962 the process of discovery   continued and   unbelievable, effective and    safer fungicides    such as, SBIs,  MBIs (tricyclazole pyroquilon etc.), strobilurins etc. were developed. Today with the availability of relatively safe and effective fungicides of 4th generation including novel fungicides, most of the diseases can be effectively controlled and crop yields can be improved. While phenylamides and fosetyl-Al have revolutionized control of downy mildews and phytophthoras, SBIs have offered control of diverse group (tricyclazole pyroquilon etc.), strobilurins etc. were developed. Today with the availability of relativly – safe and effective   fungicides of 4th generation including novel fungicides, most of the diseases can be effectively controlled and crop and crop yields can be improved. While phenylamides and fosetyl-Al have revolutionized control of downy mildews and phytophthoras, SBIs have offered control of diverse group of fungi, MBIs to rice blast and strobilurins unusually wide array of crop diseases from all four classes of plant pathogens, namely  Ascomycetes, Basidiomycetes, Deuteromycetes and Oomycetes. In view of specifically effective fungicides, farmers do not want to take risk of going the other way.


Today indiscriminate use of pesticides has undoubtedly adversely affected ecological balance resulting in pest resurgence, aggravation of minor pests, pesticide resistance, and environmental pollution and more importantly their residues in food and feed posing serious health hazards to man and animal. In view of the situation, people started to believe that pesticides are responsible for the hazards forgetting whether pesticides are really responsible or it is man for misuse and abuse of pesticides and forgetting how pesticides have supported realizing higher yields. As savior of plants and environment, I would call upon all concerned to have restrained in using pesticides and avoid misuse and abuse, which does not mean keeping pesticides at bay. One may use as per need, on recommendation of plant doctor, and not pesticide dealers.