Fruit worms are very common phenomena, but some fruits have no insect eyes on the surface, and only after eating do they find maggots inside, why is this? If you eat these bugs or eggs that appear "out of thin air", will they parasitize the human body?
The pests that appear inside the fruit are the larvae of fruit flies, which generally lay eggs on the surface of the fruit, and the hatched larvae will burrow into it to absorb nutrients. But sometimes we find that there is no damaged fruit on the surface, and these larvae will appear inside, what is the reason for this?
Try to think, what kind of fruit is most prone to this phenomenon? There is no doubt that the apple is counted, but the watermelon is not easy to appear fruit fly larvae. This is because fruits such as apples and watermelons are protected to varying degrees during their formation. This protection is not made by humans to prevent insect pests, but by the plants themselves to resist insect pests.
Usually, the seeds of angiosperms are developed from the ovary of the flower, which is equivalent to the mother's womb, and the environment is very closed, and insects cannot directly lay eggs in the ovary. If this pattern of development is followed, fruit flies do not have the opportunity to lay eggs inside apples.
But the apple is not completely developed from the ovary, but by the closed ovary and the exposed flower tray on the outside. If we cut the apple from the middle, we will see that the core seed of the apple is surrounded by "three circles", which are called the fruit core line. Strictly speaking, the part inside the core line is the real apple fruit, which is the seed and peel developed from the ovary wall, and the edible part outside is the flesh of the fruit from the flower holder. Fruit flies take advantage of this loophole, laying eggs between the flowering and fruiting periods of the apple, waiting for the apple's flower tray to slowly grow and close, and finally wrap the eggs in it.
Similarly, pears and apples have the same fruit development structure, which is also prone to this situation. Some viewers may be curious, peaches and apples are different in structure, completely developed from the ovary, why is it that peaches that are not damaged in appearance are easy to eat bugs?
This is because fruit flies will lay eggs on the surface of the peach or on the leaves close to the fruit, so that the peach is easy to pick with the leaves when it is plucked from the tree, and then the leaves are pulled out when it is shipped, and sometimes it is pulled out with the handle, and the worm will eat along the "wound" of the peach and climb in.
Completely different from these three fruits, there are many insects lurking in the bayberry, but it is not large. These bugs do not arise from the inside, but burrow into the bugs that lay eggs on the outside, and the common little white insects are the larvae of fruit flies. The insect-prone physique of bayberry is also known to everyone, its outer layer of the outer layer of the outer fruit peel cell column protrusions, the formation of soft and juicy tissue, is equivalent to the orange pulp turned over outside, which fruit fly can resist such a temptation. And the fruit structure of bayberry is also particularly easy to drill, not as hard as the peel of apples and pears, and it is easy to hide these small bugs.
These fruit fly larvae are really difficult to eat, how to deal with it is more hygienic? Since most fruit flies lay eggs on the surface of the fruit, it is important to wash the freshly bought fruit. Although the fruit fly larvae are relatively clean and do not carry any bacteria, they can completely adopt the "meat and vegetarian combination" eating method. However, fruit flies like to eat rotten food, and they will inevitably carry bacteria on their bodies, so washing fruits is only to wash away bacteria and avoid causing diarrhea. If you wash it once and are still not at ease, you can use methods such as peeling, cutting and freezing to kill the bugs.
Fruit flies' eggs and larvae live parasitically in fruit, so if we accidentally eat the eggs, can they parasitize in the stomach?
First, the larvae of fruit flies do not require much oxygen. Under completely enclosed conditions, raising fruit flies does not require a lot of oxygen. Therefore, fruit flies eaten into the digestive tract will not die due to lack of oxygen.
However, once the eggs of fruit flies enter the stomach, they often do not survive because they do not have a stratum corneum that can resist stomach acid. This is different from roundworms in our stomachs, which have a stratum corneum on the surface of their bodies that resists the erosion of digestive juices. In addition, fruit flies cannot develop or even die under conditions above 30 ° C, and the internal environment of the human body can often reach 37 ° C. Therefore, the fruit fly eggs that are eaten into it often have not hatched yet, and they become proteins and are absorbed.
However, this is not to say that fruit flies cannot parasitize eggs and larvae in humans. For example, in July 2005, Baicheng Central Hospital treated a father and daughter parasitized by fruit fly larvae. The father felt itchy in his eyes and showed no signs of relief after a week. After examination, it was found that thirteen white larvae were swimming in the upper vault of the eye, and there was a large amount of secretion in the conjunctival sac. The 6-year-old daughter found as many as 20 in her eyes, but fortunately, they went to the hospital in time to cause permanent damage to the eyes. This parasitic phenomenon is mainly caused by poor sanitary environment and poor hygiene habits, so it is common in Africa and is rare in China.
Although to us ordinary people, the fruit fly seems to just sound a little disgusting, troublesome to deal with, unlike its relatives flies, which can carry pathogens and directly threaten the safety of humans. However, the harm that fruit flies can bring is not small.
Take fruit-bellied flies, for example. Females can lay 400 eggs at a time. At 25 °C, the larvae of Drosophila melabini will molt for the first time after 24 hours and continue to grow to become second larvae. After three stages of larval development and four days of pupal stages, it only takes one day to develop into an adult worm and begin to eat. The food source of the larvae is mainly fruits with high sugar content, and the name of the fruit fly is also because of the love of eating fruit.
Fruit flies like to inject eggs on the fruit, and the melon fruit injected into the egg has no obvious symptoms of damage for a short time, but as the eggs hatch into larvae, the fruit surface of the victim will appear slightly wet and rotten, and the color becomes dull and dull. Huge numbers of fruit flies are spawning in orchards, multiplying and destroying agricultural products, making them lose their edible and economic value, and farmers bear huge economic losses.
The most worrying thing is the harm caused by biological invasions. During May this year, a courier for the American black-bellied fruit fly that attempted to enter the country illegally was seized from Qingdao, and the larvae, adults and eggs combined totaled about 7,000. It is not difficult to imagine how serious biological invasions will be caused by the unfortunate spread of so many extremely reproductive flies.
What exactly will these black-bellied fruit flies sent from the United States be used for? The "clothes" on the package label show that the person who sent the package is well aware of China's ban on the entry of foreign black-bellied fruit flies, which is obviously intentional.
In connection with the various means used by the United States to attack Our country using biological invasion, such as the "cotton bollworm" that almost destroyed China's cotton industry, and the "American white moth" that paid hundreds of millions of dollars and did not clean up, it is difficult to believe that the illegal entry of the black-bellied fruit fly this time is just a personal act of ignorance.
The crisis that a small fruit fly can erupt is enormous, and the Mediterranean fruit fly has caused great harm around the world. Native to West Africa, the fruit fly began to spread rapidly around the world after it was introduced to Spain in 1842, invading more than 80 countries and regions, endangering 250 species of fruits and vegetables. In 2015, test data from the Zhuhai Quarantine Bureau showed that a Mediterranean fruit fly female could reproduce up to 21.5 billion in three generations in 60 days, confirming that it is recognized as the most devastating pest in the world.
This is a creature that is more reproductive than rats and more difficult to kill. For us ordinary people, the way to resist flies and fruit flies is very simple, that is, to seal rotten food, throw away garbage and wash your hands frequently, and reduce the space for them to lay eggs and grow.