S.Seifullin Kazakh Agro-Technical University
Technical faculty
Department of Agricultural and post-harvesting Machines
LABORATORY WORK
) on subject) on subject on subject «Adjustment and linkage of Agricultural machines»
Theme: Pest control machinery
Astana 2012
Considered and approved at the meeting of Methodological Council of S.Seifullin Kazakh Agro-Technical University Protocol №___ «___»_______________2012 |
«APPROVED» Chairman of Methodological Council of S.Seifullin Kazakh Agro-Technical University Protocol №___ _____________A.M.Abdyrov «___»_______________2012
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Authors: Yeskhozhin К. – Candidat of Techical Sciense, Associate Professor of the Department of Agricultural and post-harvesting Machines.
Educational-methodical __________ is designed for training on discipline "Fundamentals of tractors" for students on specialty 5B080600 - "Agricultural techniques and technology"
Educational-methodical instructions are made according to the working curriculum of specialty.
Methodical instructions are intended for students of specialties 5В080600 – « Agricultural techniques and technology» and includes laboratory occupation tasks and independent work, educational literature lists and control questions for self-examination.
Reviewers: Doctor of Technical Science, Professor S.O. Nukeshev;
Reviewed and recommended at a meeting of the Department of Agricultural and post-harvesting Machines .
Protocol № ___, of "__" ___________ 2012.
Reviewed and recommended at a meeting of the methodical commission of Technical Faculty.
Protocol № ___, of "__" ___________ 2012.
Purpose of the work:
1. To study the Pest Control Methods.
2. To study the construction of Non-Chemical Techniques and its important functions.
3. To study the Chemical Control Methods
2. To study the construction of Spraying Equipment, Sprayers, The Parts of a Sprayer, The Sprayer Circuit, components and its functions.
4. Controls and adjustments
1. Pest Control Methods
In agricultural production a pest is anything that impedes or competes with the desired crop. The pest may be other plants (weeds), insects, fungi or diseases. Control of these pests is accomplished by chemical means, nonchemical treatments, or a combination of measures sometimes known as integrated pest management (IPM). IPM strives for pest control using biological, chemical and physical means that are effective, economical and environmentally friendly.
Non-Chemical Methods. These methods usually have low environmental impact but may be expensive, time-consuming or laborious. The high cost of chemicals, concerns about public health, environmental impact of chemical controls, and the growing popularity of clean agriculture and organic farming are all factors that have promoted the use of traditional and new nonchemical pest control methods.
In developed countries particularly for horticultural and fresh produce crops, there is growing interest in these methods, even though they may be less profitable than chemical controls. Traditional nonchemical pest controls have primarily focused on physical treatments.
Chemical Control Methods. Chemicals that control pests, i.e., pesticides, can be classed as either contact or systemic. Chemicals that control by contact must be in direct contact with the pest they are to control. Systemic chemicals are absorbed into the plant by roots and leaves, and cause interference with the ongoing growth process of the pest. Chemicals may be applied to the soil or to the foliage as liquids (sprays) or as solids (dust and granular).
2. Non-Chemical Techniques
Mechanical Weeding. Weeding equipment roots out and removes weeds from the soil. Its use is becoming increasingly widespread, with improved effectiveness, on row-cultivated crops, including winter cereals, vineyard and orchard crops.
The hoeing machine may be tractor-mounted or pull type. Tines or rotary hoes are fixed to the frame and penetrate the upper crust of the soil (≈ 5 cm deep) uprooting weeds from the soil portion between the rows. The treatment is effective on dry, compact soil, and a stable working depth is maintained by small wheels. Hoeing is usually combined with banding applications of herbicides in the pre- and post-emergence stages. Rows treated may vary from 2 to 8 and speeds from 2 km/h to 8 km/h.
Blade cultivators are equipped with spikes that terminate with a horizontal blade, often tine or ducksfoot shaped. These operate between rows, breaking the upper soil crust, and at a depth ≤5 cm beneath the surface, cutting weed roots and rhizomes. A similar cutting effect is obtained with a vertical disk weeder. Care must be taken in setting the operating distance from the crop to avoid damaging its root system. These types of implements also are used for operating along the tree rows in orchards. Special sensing devices detect the presence of a tree trunk and cause the implement to be shifted to the side, so that it can circumvent the plant.
Figure 1.241. Brushing machine.
The brushing machine is effective during the early stages of weed development. This implement is mounted on a tractor whose PTO drives a set of robust brushes (15–50 cm wide or more), which rotate on a vertical or horizontal axis (Fig. 1.241). The gap between brushes is adjustable; they operate between rows on the upper soil layer (<5 cm deep), uprooting weeds and carefully removing their roots from the soil, thereby excluding all possibility of resprouting. Optimal results are achieved with low speeds of rotation, a tractor forward speed of 2–6 km/h, and soil that is not too dry or compacted. A special guard protects the crops from the soil that is removed. The operator must wear adequate protection against the dust that is raised.
Figure 1.242. Manual Weeders.
The light spiked chain harrow also can be used on non-row-cultivated crops. It consists of a set of narrow, flexible, vertical steel bars. The spikes scratch the soil with a pressure that can be adjusted in accordance with the crop’s stage of development. This makes it possible, with careful adjustment, to operate during the pre-emergence stage without damaging the crop. At post-emergence, when the crop is deeper-rooted than the weeds, the best results are obtained in the earliest stages of weed development. Harrowing is less effective on wet or stony soil and is totally ineffective against deep-rooted perennial weeds. An optimal tractor speed 7 km/h and a large working width (6–24 m) make it possible to achieve high work rates.
There also are a number of smaller and simpler traditional tools based on the same principles as the machines described above (Fig. 1.242) that can be manually driven or animal drawn: the single or two-row rotary weeder, the wheel hoe, the three-tine wheel hoe. These are all low-cost types of equipment used on small farms in developing countries; the resulting quality of work is good but they are highly labor-intensive (0.01 ha/h to 0.10 ha/h).
Thermal Treatments. Heat can also be effectively used for weed and pest control. In the flame weeding technique, the area between rows and close to the crop is flamed using a gas burner that advances at a low-medium speed (2–7 km/h). The heat of the flame causes the breakup and subsequent withering of weed tissues. On the ground, the increase in temperature only extends to a depth of a few millimeters. The flame weeding equipment (Fig. 1.243) consists of a boom supporting the burners, a gas (liquid propane) tank and a delivery system.
The best results are obtained on weeds in the early stages of development. If the weeds are advanced, the treatment will require increased fuel consumption. Timeliness is an important constraint on this technique. If disregarded, costs will increase and it may not be successful.
The flame weeding operation has minimal environmental impact, but is too expensive to perform on the entire crop surface (gas consumption 150–200 kg/ha). It becomes economically feasible only when used in conjunction with other operations; flaming being restricted to the area near the rows that cannot be mechanically weeded (gas consumption 20–70 kg/ha).
Soil solarization consists of placing clear plastic mulch over moist soil for a period of 1–3 months during the summer. Solar radiation raises the soil temperature, which inactivates some fungi and kills most weed seeds and nematoda. The treatment is effective if the upper layers of the soil are held at high temperature for a total time τ that is sufficiently long. Typical values are: T = 40°C for т > 50 h; T = 45°C for т > 24 h; T = 50°C for т > 12 h.
Solarization fails if the soil does not acquire enough heat (in fact its use is recommended only in warm or tropical climates) or the soil moisture content is too low. Preliminary irrigation sometimes may be necessary.
The plastic film is laid using tractor-mounted equipment consisting of a frame supporting a spool and two lateral furrowing discs. The tractor moves at 1.5-3 km/h, unrolling the film from the spool onto the soil, while two cylinders press its edges into the furrow that has just been opened, and then cover it with soil.
Vacuum. Collection by vacuum has proved effective on insects and larvae of sufficiently large size, and in particular on potato beetles and grasshoppers. Tractor-mounted suction equipment has been developed: a hydraulically powered impeller blasts a violent air jet towards the upper part of the plants, while simultaneously generating a suction airflow at ground level. Insects and larvae are blown off leaves and fall onto the ground, where they are collected by vacuum suction. At a forward speed of 5 km/h, collection efficiency is «90% for insects and «80% for larvae. Suction is not effective against eggs.
Biological Pest-control Equipment. A more frequent pest-control practice is inundation with predators and parasites. Biological agents such as predators’ eggs, larvae, mites, ladybugs etc. are commonly supplied mixed with inactive material or organic grit (bran, sawdust, hulls etc.). The mix is often distributed manually by walking workers, who gently shake a discrete amount onto the foliage at regular intervals. Application rates are low, ranging in general from a few dm3/ha to 20–30 dm3/ha of mix.
Equipment for ground and aerial application has also been developed, and performs the following functions: it maintains the homogeneity of the contained mixture, releases the mix at an adjustable rate, protects the biological agents from any consequential damage, and improves on the work rates achievable with manual labor. In general, such equipment consists of a reservoir without an agitation system that is chilled to reduce organism activity. The mixture is metered by a variable-speed electric motor.