VII. Translate this text without the dictionary and find out the answers to the questions given below. Using fungicides efficiently for effective disease management in orchards
Tree fruit growers are well aware of the complex of pathogens that produce disease on leaves, branches, and fruit spanning the season from bud break to postharvest. There are 10 or more major diseases of apple trees alone. Managing these pathogens at levels below economic injury requires the integration of cultural and sanitation measures with prudent use of agricultural chemicals.
In this section we focus on different fungicide-use options for efficient and effective disease management. It is assumed that acceptable pruning (обрізка), fertilization, and sanitation measures known to reduce inoculum (інокулят, посівний матеріал) levels are being used and that minimal fungicide rates to maintain low disease levels are desirable.
Types of Fungicides
Pesticides used for managing fungi-caused fruit diseases are either fungicidal (they kill fungi) or fungistatic (they inhibit fungal growth). Fungicides can be separated into two categories: protectants and systemics.
Protectant fungicides protect the plant against infection at the site of application. Their characteristics are as follows:
• They provide protection against infection.
• They do not penetrate into the plant.
• They require uniform distribution over the plant surface.
• They require repeated application to renew deposit.
• They have a multisite mode of action against fungi.
• Fungi are not likely to become resistant to protectant fungi cides.
Some common protectant fungicides are Bravo, captan, copper, Dodine, Ronilan, Rovral, and sulfur.
Systemic fungicides prevent disease from developing on parts of the plant away from the site of application. Their characteristics are:
• They penetrate into the plant.
• They move within the plant.
• They often control disease by eradication.
• They often have a very specific mode of action against fungi.
Some systemic fungicides are Bayleton, Benlate, Funginex, Nova, and Rubigan.
Modes of Action
Fungicides can act on fungi by (1) inhibiting energy production (e.g., sulfur, copper, manzate, and captan), (2) interfering with cell structure (e.g., Dodine), and (3) interfering with growth (e.g., Benlate, Funginex, Bayleton, Nova, and Rubigan).
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1. Why is it so important to integrate cultural and sanitation measures with prudent use of agricultural chemicals to manage the plant pathogens?
2. What differences are there between Protectant fungicides and Systemic fungicides?
3. How can fungicides can act on fungi?
VIII. Translate this text without the dictionary and find out the answers to the questions given below.
European Red Mite
Description and life cycle
The European red mite (кліщ червоний плодовий), Panonychus ulmi (Koch), a major tree-fruit pest attacking apples, stone fruits, and pears, is considered by many growers throughout Pennsylvania to be the most important apple pest. The mite was introduced into North America from Europe in the early 1900s and is now established in most fruit-growing areas.
The rate at which mites develop is primarily temperature dependent. Hot, dry weather favors development, while cool, wet weather delays mite activities. Overwintering eggs are laid in groups on roughened bark, in crevices and cracks, and around bud scales on twigs and branches. Eggs begin to hatch at prepink bud (відокремлення пуп’янок) stages and continue throughout bloom. Young mites move to newly opened leaves where they feed, mature, and reproduce. The first generation requires approximately three weeks to develop; summer generations are completed in 10 to 18 days.
Each female is capable of laying 35 eggs during her average life span of 18 days. Eight to 10 generations occur during the year.
Mites feeding on leaves cause injury to the tree by removing leaf tissue. The most serious injury occurs in early summer when trees are producing fruit buds for the following season. Moderate to heavily infeсted trees produce fewer and less vigorous fruit buds. Mites feeding on leaves also reduce the ability of leaves to manufacture enough food for desirable sizing of fruit. Characteristic brown foliage that, in severe cases, becomes bronze, results from heavy mite feeding.
Mite predators (хижаки), such as predaceous mites and the black ladybird beetle (Сонечко), Stethorus punctum, are generally distributed in commercial apple orchards and contribute significantly to control of mites.
Managing mites in the apple integrated pest management program
Our integrated pest management program for apples depends largely on a miticide (акарицид) to suppress mites until the Stethorus punctum population reaches levels high enough to regulate the mite population below economic injury levels. This black ladybird beetle is a voracious predator of European red mites. By conserving Stethorus in their orchards, growers in much of Pennsylvania often can reduce the number of pesticide applications to control mites. To use this beetle, several practices must be followed:
• Pesticides that are toxic to the beetle should be avoided .
• The alternate row middle pesticide application method is recommended, but certain conditions will dictate the use of complete sprays. These conditions include extremely high mite pressure, use of a pesticide of questionable efficacy, and weather conditions conducive to a rapid increase in the mite population.
• The population densities of the mites and the beetles must be known in order to determine if the beetle population is sufficient to overcome the mite population or if the aid of a miticide is needed.
Stethorus adults emerge from overwintering sites in and around orchards between the half-inch green and petal (пелюсток) fall stages of apple development and quickly move into the trees to begin feeding on overwintered mite eggs. As foliage develops on the fruit trees and mites begin to hatch and disperse onto the leaves, the beetles follow to feed on these motile mites.
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1. What weather favors the European red mite activities?
2. When do the European red mite eggs begin to hatch?
3. What damage do European red mites make for orchard trees?
4. What is the main European red mite predator?
5. What practices must be followed to use the black ladybird beetle in orchards?
6. How do black ladybird beetles contribute to control of red mites?
GRAMMAR EXERCISES