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Solid formulations such as dust, wettable powder or granules, the active ingredient is mixed with inert material. The concentration is expressed as:

Active ingredient (%) in the total weight of commercial product.

Calibration is the process of measuring and adjusting the amount of pesticide your equipment applies or delivers to a specific area. The purpose of calibration is to ensure your equipment is applying the correct amount of material uniformly over a given area.

Equipment is manufactured to be adjustable. Charts or tables may be provided to assist the operator in making adjustments to the settings. These recommended settings, however, are only approximate and may not be appropriate for all situations. Therefore, your equipment must be calibrated periodically. This depends on the type of equipment and the frequency of use. The application rate of the sprayer is affected by travel speed, nozzle size, and sprayer pressure. Equipment is calibrated by making a trial run on some premeasured area and measuring the output. For example, using a hand-held sprayer, spray a premeasured test area with water using the same pressure and techniques (i.e., travel speed and equipment) you would use when applying the pesticide. After spraying the test area, determine how much water was used. This volume can then be used to calculate the amount of water and pesticide needed to cover the intended application area.

The time invested in calibrating your equipment is time well spent. Accurate calibration to determine the application rate under your operating conditions is important for cost, efficiency and safety.

The objective of correct pesticide application cannot be achieved without good quality Plant Protection Equipment. A sound designed machine shall be proficient as far as pesticide distribution and delivery to the target in minimum time with least wastages is concerned. Hence, the machines should be tested to ascertain that they are:

i) Common Maintenance

Clean outer surface with brush or cotton waste by using plenty of water or kerosene oil.

Oil the moving or rubbing surfaces of parts with lubricating oil or grease.

Filter the chemical solution/ fuel oil mixture while pouring into the tanks. Make the caps or lids leak-proof with gaskets.

Flush the equipment with clean water to wash inside parts of containers, tubes and nozzles to be free from chemicals.

Any sprayer nozzle essentially breaks the liquid into small droplets and throws them. All nozzles in the field produce rangesof droplets of different size called spray spectrum. The hydraulic nozzles have wide range of size of droplets whereas the rotary nozzles have narrow range. Adroplet of 400 µm diameter is 1000 times bigger in volume than a droplet of 40 µm. The volume of spherical droplets can be worked out as 4/3 µr3. So if the droplet size of aspraying system could be reduced to half, then there will be 8 fold increases in the number of droplets and the coverage will also increase.

Majority of the pesticides are applied as sprays. The liquid formulations of pesticide either diluted or directly are applied in small drops to the crop by different types of sprayers. Generally the wettable powder, EC formulations are diluted suitably with water which is a common carrier of pesticides. However, in few cases oil is used as carrier of pesticides.

Spraying nozzle is a device for emitting spray liquid, breaking it up into small droplets and throwing the droplets away from the nozzle orifice. Different designs of nozzle are used to produce appropriate droplet size spectrum. In order to break the liquid into droplets energy is needed. The spray nozzles therefore are classified as:

Pesticide Dusting

The dusting powders are low concentration ready to use type, dry formulations containing 2 to 10% pesticide. The inert material or dry diluents is talc, soapstone, attapulgite, etc. and it is non toxic. The sulphur dust is not diluted with inert material.

Sprayer is an equipment in which the spray fluid is broken up into fine droplets and ejected under pressure. Actually, the function of the sprayer is to provide the spray fluid with some energy so that it can be broken into fine droplets through the nozzle and propelled to the target. The energy can be produced manually or with the help of any other source of power. There are a variety of sprayers.

Type of Sprayers: There are a variety of sprayers.

The Effectiveness of a Pesticide in Controlling a Disease and Pest Depends on

Using the right pesticide for the target disease & pest.

Applying the pesticide at the right time.

Applying the pesticide in the right amount.

Applying the pesticide to the right place.

The behavior of pesticides is dependent on many factors, so be sure to consider everything from light and temperature to moisture and pH and recognize that all the factors will impact the active ingredient. Here is some information on these topics, and others, which will improve pest management success.

1.Identification: The first step to disease and pest management success is the proper identification of the insect, disease or weed pest. Without identification of the pest, controls may be misused or improperly timed.

2.Time of Application: Time of application of pesticides plays major role in optimizing pesticidal performance. Early morning or late afternoon are the best times to spray. Dust formulations should be apply in early morning hours (6 am).In the case of foliar spray, it should be done in morning hours between 8 am to 11 am. Avoid spraying during the heat of the day.

3.Water Quality and pH: Primary factors important in water quality are pH and alkalinity (bicarbonates). Most of the pesticides show high efficiency in slightly acidic to slightly basic water pH (i.e. 6.5 to 7.5). Many water sources in alkaline pH (<7.0). Alkali pH (7.5>) is always harmful for pesticides. High pH levels are responsible for alkaline hydrolysis, a process that breaks down the active ingredient in many insecticides, fungicides and herbicides.Add a buffer agent to lower spray solution to a pH of 5.5-6.5. This will give better initial knockdown and longer residual action.

Antibiotics are substances which are produced by micro-organisms and which act against micro-organisms. It is also defined as secondary metabolites produced by microorganism, which inhibits the growth of another microorganism. Most antibiotics known uptill now are products of actinomycetes and some are from fungi and bacteria. The use of the antibiotics in managing plant diseases, particlulaty the disease caused by bacteria, mycoplasma and ricketsia, is well demonstrated and are thought to be effective means because of their selective action directed towards causal agents not to the infected host. The mode of action of the antibiotics varies depending on site of action which in turn detrmines their specificity towards given target host (Table 12). Some time mixture of antibiotics are in practice in managing the diseases to reduce delay the chances of resistance development against a particular antibiotic by the causal agent. The most useful antibiotic mixture is streptocycline, which contains streptomycin and tetracycline.

1. Bordeaux Mixture

It was invented in the Bordeaux region of France by PM Millardet (1982).

Also called Bordo Mix.

Mixture of Copper sulfate (CuSO₄), Slaked lime and Water.

It is known locally in France as Bouillie Bordelaise.

Before applying fungicides in field at large areas, it is required to be thoroughly investigated under laboratory conditions for its efficacy on pathogen, subjected. Basic methods of testing these chemicals against subjected pathogen, under laboratory conditions are described here.

1. Poisoned Food Technique

Principle

The principle involved in this technique is to poison the medium with fungicides and then allow a teat fungus to grow on such medium. The test may be conducted both on solid and liquid medium.

Pesticides sustain food production and control disease and pests. They are vital for crop production and instrumental in continuous increase in food production. The consumption of pesticide in India is one of the lowest in the world. India uses a low amount of 0.5 kg/hectare pesticide compared to 7.0 kg/ hectare by USA, 2.5 kg/hectare by Europe, 12 kg/hectare by Japan and 6.6 kg/ hectare by Korea. However, despite the low consumption of pesticides, India has more problem of pesticide residues vis-a-vis other countries and these have entered into food products and underground water because of

Pesticide Toxicity

Chemical tactics to manage pests can include many types of compounds. Some merely repel or confuse pests. Some interfere with weed photosynthesis, insect molting processes or development in some way. Others, including some botanical and most conventional insecticides are broadly toxic to living systems. The term pesticide literally means “pest killer". Generally speaking, when using pesticides, we are trying to garner the advantages of using pesticides while minimizing the risk to humans and other non-target organisms. Risk to humans of pesticide use is often described as:

Definition

“Biological pesticides”, or “Biopesticides” as the name suggests, are naturally occurring substances that biologically control harmful pests, especially among field crops. These are naturally produced bio chemical materials basically non-toxic to the environment that can be employed in pest control. Biopesticides could mean living organisms (bacteria, virus, and algae), their products (biochemicals produced by them) and also plant byproducts. Biopesticides offer an ecologically effective solution to the harmful effects of synthetic pesticides.

Strobilurins are a group of chemical compounds used in agriculture as fungicides. They are part of the larger group of QoI inhibitors, which act to inhibit the respiratory chain at the level of Complex III.Some common Strobilurins are azoxystrobin, kresoxim-methyl, picoxystrobin, fluoxastrobin,oryzastrobin, dimoxystrobin, pyraclostrobin and trifloxystrobin. Strobilurins represented a major development in fungus-based fungicides. They were extracted from the fungus Strobilurus tenacellus. They have a suppressive effect on other fungi, reducing competition for nutrients; theyinhibit electron transfer inmitochondria,disrupting energy metabolism and preventing growth of the target fungi. Strobilurins are miracle fungicides ever developed with novel mode of action & mobility that qualifies the Unique New Generation Fungicides controlling Pathogen from diverse class.

Environmental protection Agency (EPA)has established category of pesticides called “Reduced Risk” pesticides to encourage the development, registration and use of products which could result in reduced risks to human health and the environment. New Generation pesticides are considered for “Reduced Risk” status if they have at least one or more of the following status: low risk to human health, low toxicity to non target organisms, low potential to contaminate ground water, surface water or other valued environmental resources and have the potential to expand the adoption and effectiveness of IPM.

There is a common practice of using the terms spurious, counterfeit, misbranded, illegal, sub-standard and others interchangeably and this often creates confusion among scientist, industrialist and extension officer. Spurious and counterfeit pesticides are the two major words used to describe all kind of anomalies in the pesticides. Hence, there is a need to have a clear understanding of these and differences between them.