characteristics

this disease mainly harms flowers and fruits. The damaged flowers and fruits were waterlogged in the early stage, then softened gradually, and the surface of the affected parts was covered with gray-green mold. Eventually, flowers and fruits will rot. In the later stage, the diseased part sometimes grows black sclerotia.

regularity

The pathogen is Botrytis cinerea. Pathogens overwinter on the sick and disabled, or in the soil and spread by airflow. Bacteria like high humidity and low temperature conditions, the optimum temperature is 18-23℃, the relative humidity is above 9%, and it is suitable for onset in weak light. Protected cultivation, cloudy days in winter and spring, low temperature, high density, poor ventilation and light transmission, high humidity, so the disease is more serious.

control

(1) strengthen field management. Clean up the sick and disabled, keep the field clean, prevent the spread of germs and control the temperature.

(2) The water should be irrigated under the film or drip irrigation, and the humidity at night should be less than 8%. When the humidity is high, measures should be taken to reduce the humidity.

(3) In the later stage of production, the old leaves should be cleaned in time, and ventilation and light transmission should be increased to make the plants grow healthily and increase the disease resistance.

(4) chemical control. Spray 1,-1,5 times of 5% chlorphenamine wettable powder and 4 times of 5% mancozeb wettable powder once every 6-7 days for 2-3 times.

Cotton rot

Features

It mainly damages fruits, sometimes leaves, stems and other parts. At the beginning of the fruit disease, it was oval and dark green with water immersion. Under the condition of air drying, the diseased spot is slightly depressed and does not expand quickly, only the subcutaneous pulp is rotten and the surface is covered with white mold. When the temperature is high and the humidity is high, the diseased spots spread rapidly, and the whole fruit turns brown and soft rot, and the surface is covered with white mold layer, which causes the diseased melon to rot in the field. When the leaves are damaged, they are dark green and round, forming irregular water-soaked lesions. When the humidity is high, they are soft and rotten like scalding water.

Regularity

Cotton rot of zucchini is caused by fungal infection of pythium melongenae. The pathogen overwinters in the soil as oospores, germinates under suitable conditions in the following spring, and produces sporangia and zoospores, or directly grows bud tubes to invade the host, and then produces sporangia and zoospores on the diseased remains, which are spread by rain or irrigation water and invade the fruits, and finally forms oospores in the diseased tissues for overwintering. Bacteria are mainly distributed in the topsoil, and the bacteria increase rapidly after rain or high humidity. Low soil temperature and high humidity are conducive to the disease.

prevention and control

(1) use high border cultivation to avoid flooding, drain water in time after heavy rain, and pad the melons after fruiting to prevent them from getting wet and getting sick.

(2) increase the antibiotic bacteria in the soil, inhibit the growth of pathogenic bacteria and reduce the damage.

(3) chemical control: at the initial stage of the disease, spray with 1 times of 2% agrotis once every 1 days for 2 ~ 3 times continuously.

fruit deformity

causes

improper control of water and fertilizer. Cucurbita pepo is easy to form a pointed-billed melon due to insufficient water and fertilizer in the early stage, a thin-waisted melon due to insufficient water and fertilizer in the middle stage, and a slender and crooked melon due to insufficient water and fertilizer in the later stage. However, in the medium term, excessive water and fertilizer are easy to form a big belly melon; Poor pollination, uneven distribution of pollen, so that the parts with insufficient pollination are concave, forming deformed melons; Too high or too low temperature will affect photosynthetic efficiency, make the nutrition insufficient and inhibit the normal development of fruits; Cucurbita pepo's own female flowers are defective or bisexual to form fruits, which become deformed melons.

Dwarf

This type of variety has short vines and short internodes, and is relatively early. The vines are 3 ~ 6 cm long. The first female flower is inserted in the 3rd to 8th nodes, and then it appears every 1st to 2nd nodes or every node. The main varieties are mosaic zucchini, standing zucchini and a nest of monkey zucchini.

Semi-creeping

This type of variety has a slightly longer internode, with a vine length of 6-1 cm. The first female flower of the main vine is planted on the 8th-11th node, which is a medium-mature variety. Most of these varieties are local varieties. For example, the flower-skinned zucchini in Linyi, Shanxi Province, and the semi-sprawling naked zucchini newly bred by the Vegetable Research Institute of Shanxi Academy of Agricultural Sciences. The cultivation of this type of zucchini is rare. However, with the continuous improvement of the cultivation techniques of zucchini, the proportion of semi-trailing zucchini planted in greenhouse will increase.

creeping

this type of plant has strong growth potential and long internodes, and the main vine can reach more than 15 ~ 4 cm. The first female flower of the main vine generally appears after the 1th node, which is a late-maturing variety. Cucurbita pepo has stronger disease resistance and heat resistance than dwarf type, but weak cold resistance. The fruit parts are scattered, the maturity period is not concentrated, the harvest period is longer, the fruit meat is tender, the fiber is less, the quality is good, the weight of a single fruit is 2 ~ 2.5 kg, and the total output is higher. Suitable for summer cultivation. The main varieties are stupid zucchini, pull-seedling zucchini and sprawling zucchini in Jiaocheng, Shanxi.

There are two varieties of zucchini, namely pearl melon and stirred melon. The growth and development of Cucurbita pepo is similar to that of pumpkin, with strong growth potential and short, upright and open plant type. The fruit is spherical, and the skin is dark green and bright with gray-green spots. The fruit grows fast and the growth period is short, and the weight of a single melon can reach 3 grams 5 ~ 7 days after flowering. One plant can bear three commercial melons at the same time, and the number of fruits set and picked per plant is more, so the continuous fruiting performance is good. Cultivation requires fertilizer and water.

Cucurbita pepo is another variety of zucchini. It is planted in Shandong, Hebei and other places. This variety has strong growth potential, small leaves, deep notch, oval fruit and single melon weighing .7 ~ 1 kg. Mature melons have dark yellow skin, light yellow skin, orange background and dark brown longitudinal stripes. The flesh of melon is thick and light yellow, and the tissue of melon flesh is fibrous. Old melons are often used for food. Generally, after the whole melon is boiled or steamed, it is cut horizontally, and the melon meat is stirred with chopsticks into vermicelli or jellyfish skin, which can be eaten when it is cold, so it is called stirred melon.