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Diseases of Agricultural Plants
Plants, like animals, are subject to diseases of various kinds. It has been estimated that some 30, 000 different diseases attack our economic plants; forty are known to attack corn, and about as many attack wheat. The results of unchecked plant disease are all too obvious in countries which have marginal food supplies. The problem will soon be more widespread as the population of the world increases at its frightening rate. Even in countries which are now amply fed by their agricultural products there could soon be critical food shortages. It is easy to imagine the consequences of some disastrous attack on one of the major crops; the resulting famines could kill millions of people, and the resulting hardship on other millions could cause political upheavals disastrous to the order of the world.
Some plants have relative immunity to a great many diseases, while others have a susceptibility to them. The tolerance of a particular plant changes as the growing conditions change. A blight may be but a local infection easily controlled; on the other hand it can attack particular plants in a whole region or nation. An example is the blight which killed virtually every chestnut tree in North America. Another is the famous potato blight in Ireland in the last century. As a result of that , it was estimated that one million people died of starvation and related ailments.
Plant pathologists have made remarkable strides in identifying the pathogens of the various diseases. Bacteria may invade a plant through an infestation of insect parasites carrying the pathogen. A plant can also be inoculated by man. Other diseases might be caused by fungus which attacks the plant in the form of a mold or smut or rust. Frequently such a primary infection will weaken the plant so that a secondary infection may result from its lack of tolerance. The symptoms shown may cause an error in diagnosis, so that treatment may be directed toward bacteria which could be the result of a susceptibility caused by a primary virus infection.
1. How many diseases are known to attack wheat?
A. Around 30, 000.
B. Around 140.
C. Around 29, 960.
D. Around 40.
2. According to this passage, which of the following would a plant disease result in if left unchecked?
A. A world war.
B. Border conflicts.
C. Rations of grain and meat.
D. Social upheavals.
3. What is the main idea of the second paragraph?
A. Some plants have relative immunity to a great many diseases, while others have a susceptibility to them.
B. The tolerance of a particular plant changes as the growing conditions change.
C. A blight killed virtually every chestnut tree in North America.
D. A blight may be a national infection.
4. According to the passage, some plant diseases can be prevented by
A. killing parasites.
B. inoculation.
C. killing insects.
D. improving growing conditions.
5. Which of the following statements is not true?
A. Some plant diseases may be caused by bacteria.
B. Some plant diseases may be caused by pathogens.
C. Some plant diseases may be caused by fungus.
D. Symptoms are always helpful in identifying diseases.
The Business of Weddings
Every couple who goes to the alter believes that they will make that trip only once in their lives. They want the day to be perfect, and they are asking for much more than good weather. They want the most beautiful clothes, the freshest flowers. Moreover, her family who will foot the bill is not in any mood to economize.
A quick look at any bride magazine will reveal that plenty of attractive goods and services compete for a share of the wedding budget. Besides the obvious choices of rings, dresses, flowers, and photographs, there are the less apparent expenses: a lavish cake, a rehearsal dinner, a reception, music for both the ceremony and the reception, tips, and even napkins and matchbooks printed with the couples names and the wedding date.
As the arrangements are generally complicated, there are plenty of services that can be hired to help with the planning and execution of the every aspect of the wedding: planning the photographs, selecting the wedding rings, choosing the flowers, picking the honeymoon spot, and so on. One magazine lists over 350 such pamphlets published of course by businesses who have something to offer. Considering that weddings do more than 12 billion dollars worth of business annually in the US alone, such activity isnt surprising.
What is surprising is that no one company dominates the industry. it seems that when people plan for a day as special to them as a wedding, they resist standardization. They turn instead to the small local suppliers known to them or to their friends. Family members of friends often serve as photographers, caterers and musicians. This not only helps bring the wedding cost down, but makes it more personal.
What about the couple that doesnt want to take in this billion-dollar industry? They can go to city hall and get married for less than the price of a hamburger.
1. What does the expression this billion-dollar industry refer to?
A. The budgets of weddings.
B. The business of weddings.
C. The planning and execution of weddings.
D. The high wedding expenses.
2. Which of the following is not mentioned?
A. The wedding budget.
B. The wedding breakfast.
C. The wedding date.
D. The wedding cost.
3. Not a single company can dominate the industry because
A. people resist standardization.
B. parents want to reduce the wedding cost.
C. many couples cant afford more than the price of a hamburger.
D. family members are surprised at the complicated arrangements.
4. Which of the following can best replace the phrase foot the bill in the first paragraph?
A. play football
B. bring the bill
C. approve the bill
D. pay the bill
5. The writers attitude towards the annual 12-billion-dollar business of wedding appears to be
A. positive.
B. negative.
C. indifferent.
D. objective.
Diseases of Agricultural Plants
Plants, like animals, are subject to diseases of various kinds. It has been estimated that some 30, 000 different diseases attack our economic plants; forty are known to attack corn, and about as many attack wheat. The results of unchecked plant disease are all too obvious in countries which have marginal food supplies. The problem will soon be more widespread as the population of the world increases at its frightening rate. Even in countries which are now amply fed by their agricultural products there could soon be critical food shortages. It is easy to imagine the consequences of some disastrous attack on one of the major crops; the resulting famines could kill millions of people, and the resulting hardship on other millions could cause political upheavals disastrous to the order of the world.
Some plants have relative immunity to a great many diseases, while others have a susceptibility to them. The tolerance of a particular plant changes as the growing conditions change. A blight may be but a local infection easily controlled; on the other hand it can attack particular plants in a whole region or nation. An example is the blight which killed virtually every chestnut tree in North America. Another is the famous potato blight in Ireland in the last century. As a result of that , it was estimated that one million people died of starvation and related ailments.
Plant pathologists have made remarkable strides in identifying the pathogens of the various diseases. Bacteria may invade a plant through an infestation of insect parasites carrying the pathogen. A plant can also be inoculated by man. Other diseases might be caused by fungus which attacks the plant in the form of a mold or smut or rust. Frequently such a primary infection will weaken the plant so that a secondary infection may result from its lack of tolerance. The symptoms shown may cause an error in diagnosis, so that treatment may be directed toward bacteria which could be the result of a susceptibility caused by a primary virus infection.
1. How many diseases are known to attack wheat?
A. Around 30, 000.
B. Around 140.
C. Around 29, 960.
D. Around 40.
2. According to this passage, which of the following would a plant disease result in if left unchecked?
A. A world war.
B. Border conflicts.
C. Rations of grain and meat.
D. Social upheavals.
3. What is the main idea of the second paragraph?
A. Some plants have relative immunity to a great many diseases, while others have a susceptibility to them.
B. The tolerance of a particular plant changes as the growing conditions change.
C. A blight killed virtually every chestnut tree in North America.
D. A blight may be a national infection.
4. According to the passage, some plant diseases can be prevented by
A. killing parasites.
B. inoculation.
C. killing insects.
D. improving growing conditions.
5. Which of the following statements is not true?
A. Some plant diseases may be caused by bacteria.
B. Some plant diseases may be caused by pathogens.
C. Some plant diseases may be caused by fungus.
D. Symptoms are always helpful in identifying diseases.
The Business of Weddings
Every couple who goes to the alter believes that they will make that trip only once in their lives. They want the day to be perfect, and they are asking for much more than good weather. They want the most beautiful clothes, the freshest flowers. Moreover, her family who will foot the bill is not in any mood to economize.
A quick look at any bride magazine will reveal that plenty of attractive goods and services compete for a share of the wedding budget. Besides the obvious choices of rings, dresses, flowers, and photographs, there are the less apparent expenses: a lavish cake, a rehearsal dinner, a reception, music for both the ceremony and the reception, tips, and even napkins and matchbooks printed with the couples names and the wedding date.
As the arrangements are generally complicated, there are plenty of services that can be hired to help with the planning and execution of the every aspect of the wedding: planning the photographs, selecting the wedding rings, choosing the flowers, picking the honeymoon spot, and so on. One magazine lists over 350 such pamphlets published of course by businesses who have something to offer. Considering that weddings do more than 12 billion dollars worth of business annually in the US alone, such activity isnt surprising.
What is surprising is that no one company dominates the industry. it seems that when people plan for a day as special to them as a wedding, they resist standardization. They turn instead to the small local suppliers known to them or to their friends. Family members of friends often serve as photographers, caterers and musicians. This not only helps bring the wedding cost down, but makes it more personal.
What about the couple that doesnt want to take in this billion-dollar industry? They can go to city hall and get married for less than the price of a hamburger.
1. What does the expression this billion-dollar industry refer to?
A. The budgets of weddings.
B. The business of weddings.
C. The planning and execution of weddings.
D. The high wedding expenses.
2. Which of the following is not mentioned?
A. The wedding budget.
B. The wedding breakfast.
C. The wedding date.
D. The wedding cost.
3. Not a single company can dominate the industry because
A. people resist standardization.
B. parents want to reduce the wedding cost.
C. many couples cant afford more than the price of a hamburger.
D. family members are surprised at the complicated arrangements.
4. Which of the following can best replace the phrase foot the bill in the first paragraph?
A. play football
B. bring the bill
C. approve the bill
D. pay the bill
5. The writers attitude towards the annual 12-billion-dollar business of wedding appears to be
A. positive.
B. negative.
C. indifferent.
D. objective.
