Why doesn t lettuce attract insects, why don t insects eat lettuce

<> first, it is not insect-free: the insect pests of green vegetables are usually green worms from the eggs laid by vegetable butterflies, and some are insect pests caused by snails and aphids, and lettuce will also grow insects, but the probability of insects will be much smaller than that of other green vegetables;

Second, the influence of the season: some seasons are natural enemies for insects, and some seasons are paradise for insects, usually winter lettuce will not be affected by insect pests, the main reason is that many insects are frozen to death due to the winter temperature;

Third, pesticides are used: although lettuce is not favored by rapeseed butterflies and green insects, it has attracted the attention of snails and aphids because of its full moisture, so if such pests are encountered, lettuce growers have to take measures to use some pesticides to control pests, so as to achieve the purpose of making lettuce free of insects.

Hello! Lettuce also has worms, but the chance of worms is much smaller than that of other greens.

Lettuce is actually a common name for leaf lettuce, so the lettuce contained in the lettuce stems and leaves makes the taste bitter, and the insects naturally don't like to eat it, so the reproduction on lettuce is naturally less.

Lettuce likes to be cool, generally at 15-20 degrees of growth and development is the best, the yield is the highest, the quality is the best, so the general vegetable farmers in the process of breeding lettuce, will take measures to maintain an optimal temperature in the greenhouse.

And this temperature bug can still survive, but relatively rarely. In order to avoid insect infestation, pesticides are usually sprayed.

In general, lettuce is not really insect-free, but due to its own secretion of lettuce, pesticide treatment and seasonal reasons are relatively few.

Lettuce contains lettuce and erucic acid, a white milky liquid that is slightly bitter and repellent from insects; It has a special odor and has a destructive function on the insect body. People have an enzyme that can destroy erucic acid, so there is no harm in eating lettuce. In addition, rapeseed, bitter horseweed, oilseed lettuce, lettuce, sweet potato leaves, etc. are all insects that are unwilling to eat.

Only in extreme cases, such as when there are no other plants, will insects visit these plants.

First, it is not insect-free: the insect pests of green vegetables are usually green insects from the eggs laid by vegetable butterflies, and some are insect pests caused by snails and aphids.

The second yard fights Liang 2, seasonal influence: some seasons are natural enemies for insects, some seasons are paradise for insects, usually winter lettuce will not be affected by insect pests, the main reason for the delay is that many insects are frozen to death due to the winter temperature;

Third, pesticides are used: although lettuce is not favored by rapeseed butterflies and green insects, it has attracted the attention of snails and aphids because of its full moisture, so if such pests are encountered, lettuce growers have to take measures to use some pesticides to control pests, so as to achieve the purpose of making lettuce free of insects.

Lettuce does not grow worms because lettuce seeds contain lettuce and erucic acid.

The reason why lettuce does not have worms (or rarely worms) is because lettuce contains lettuce and erucic acid, and its taste is slightly bitter, which is a harmful substance for insects, and it will cause damage to its internal speech after eating, so insects are generally reluctant to eat lettuce, and only in extreme cases such as when there are no other plants to eat, insects will eat lettuce.

Growth habits

Lettuce likes a cold environment, neither cold tolerant, nor heat tolerant, the suitable temperature for growth is 15 -20, and the growth period is 90-100 days. The seeds are more resistant to low temperatures and germinate at 4 o'clock. The suitable temperature for germination is 18-22, and almost no germination when it is higher than 30.

During the growth period of the plant, it likes a cool climate, and the most suitable growth is 15-20, with high yield and excellent quality; Consistently higher than 25, poor growth, coarse and old, slightly bitter leaves. However, it is also quite hardy, and even short-term sub-zero temperatures do not hinder growth.

Lettuce has a well-developed root system, wax on the leaf surface, and is quite drought tolerant, but it is cultivated on fertile and moist soil, with high yield and good quality. The pH value of the soil is considered suitable.

Main categories

Lettuce can be divided into bulb lettuce, wrinkled lettuce and erect lettuce according to the growth form of the leaves.

Knot ball lettuce

The main characteristic of lettuce is that its apical leaves form leaf balls. The leaves are entire, serrated or deeply lobed, the leaf surface is smooth or shriveled, and the apical leaves form leaf globules, round or rounded. The main varieties are Dahu 659, Qianwei 75, Salinas, Beishan No. 3, Mamic, Emerald and so on.

Wrinkled leaf lettuce

The main characteristic of wrinkled leaf lettuce is that it does not bulb. Basal leaves, the leaves are oblong, the petioles are long, the leaf margins are wavy or deeply lobed, the leaf surface is shrunken, and the clusters of leaves are like large flowers. The main varieties are "Red Sail" purple leaf lettuce, safflower leaf lettuce, green wave, Dongshan lettuce and so on.

Erect lettuce

The main characteristics of erect lettuce are narrow and long, upright growth, full or serrated leaves, thick leaves, coarser flesh, and poor flavor. This variant has fewer varieties and is not widely distributed in the country, and is rarely cultivated in the country.

<> lettuce does not have worms (or rarely worms) because lettuce contains lettuce and erucic acid, and its taste is slightly bitter, which is a harmful substance for insects, and it will cause damage to its internal organs after eating, so insects are generally reluctant to eat lettuce, and only in extreme cases such as when there are no other plants to eat, insects will eat lettuce.