Contents

Preface
I. Introduction
II. Classification of Plant Protection Devices
III. Sprayers
IV. High Volume and Low Volume Spraying
V. Calibration of Spraying Pump
VI. Dusting Machinery
VII. Dusting Vs Spraying
VIII. Fumigators
IX. Other Plant Protection Equipments
X. Care and Maintenance of Plant Protection Devices
XI. Precautions During Application of Pesticides. Appendix

Preface

We are losing foodgrains worth Rs 6 billion every year because of weeds, insect pests and diseases. At this point, protection of foodgrains which we produce is more important than production. For successfully tackling of these destructive agents, an integrated weed/pest/disease management systems should be adopted. Use of chemicals such as herbicides, pesticides and fungicides will be an integral part of these systems. For the safe and efficient application of these chemicals to field crops, use of various plant protection devices is unavoidable. This booklet exclusively deals with various plant protection devices including their structure, mechanism of operation, mode of operation, efficiency, etc. Besides, maintenance of plant protection devices, and precautions to be exercised while applying plant protection chemicals have also been discussed in this article.

Dr. K.T. Chandy, Agricultural & Environmental

I. Introduction

Success in pest control depends not only on the use of proper chemicals at the correct time, but also upon their proper and uniform application by judicious selection of plant protection appliances. Pesticides are generally applied to the plants as dusts, sprays, concentrates, fumigants, aerosols, granules, mist and used for seed dressing. These formulations are used on the crop foliage or to the soils with the help of plant protection appliances or equipments. The foliar applications are done by means of sprayers of dusters and soil applications are made by sprayers, dry chemical applicators, injectors, smoke generators, fumigators, seed dressers, aerosol projectors, rat trappers and bait containers. Treatment of cash crops by using aircraft is also commonly practiced in some countries, but rarely in India where the fields are usually smaller in size.

Efficient use of crop protection equipments is a very important factor to any pesticide application. In many cases, faulty use of equipment results in poor control of pests. The location of the pest or the most affected portion of the plant is first determined and then accordingly, the plant protection device is adjusted. Other essential requirement of any plant protection equipment is that it discharges the chemicals at a uniform and controllable rate. The equipment should also distribute the pesticide over the area being treated and it should be easily calibrated to apply a required dosage. Apart from economic considerations, the choice of an equipment also depends upon the physical structure and layout of the crops for e.g. both coffee and cotton require an extensive spray programme during their growth and as the height and leaf density increases, it becomes difficult to achieve adequate penetration of spray droplets inside the crops when these crops approach maturity.

II. Classification of Plant Protection Devices

Plant protection devices can broadly be classified into following. three categories: (i) sprayers, (ii) dusters, and (iii) fumigators. They are either hand operated or power operated.

Plant Protection Devices

1. Sprayers

A. Hand operated
1. Hand atomizer 2. Hand compression sprayer, 3. Paddle pump sprayer, 4. Knapsack sprayer pump 5. Stirrup sprayer, sprayer
B. Power operated
1. Hydraulic sprayer 2. Mist sprayer, 3. Fog or smoke sprayer, 4. Aerial spraying

2. Dusters
A. Hand operated
1. Hand duster 2. Hand rotary duster 3. Bellow duster
B. Power operated
1. Power duster


3. Fumigators
1. Cyno-gas pump
2. Soil injector