Field Operation Management and Disease Control of Flowers

As soon as many flower farmers mention disease prevention and control, they are "spraying medicine" (spraying pesticides), "what kind of medicine", "a few covers, a few spoons". However, chemical control is only one of the methods of disease control, if the field operation is not managed properly, spraying fungicides alone can not control the disease economically and effectively. Flowers are crops with higher economic value, and their cultivation concept should also be promoted. In the cultivation mode of comprehensive management, disease management is one of them, but it is not an independent one. It can not be operated and managed with the concept of spraying disease only. Only comprehensive management ability to achieve comprehensive prevention and control of flower diseases.

Pathogeny

Diseases caused by abiotic organisms are called non-communicable diseases or physiological diseases because they are not contagious to each other. Diseases caused by fungi, bacteria and other pathogens are contagious and are called infectious diseases.

Etiology of physiological diseases

Inappropriate temperature, unsuitable light, water imbalance, unsuitable nutritional conditions, excessive salinity of soil, harmful gases and substances, unsuitable pH of soil and so on will affect the normal growth and development of flowers and lead to diseases. Therefore, it can be known that physiological diseases can not be effectively controlled by "medication".

Causes of infectious diseases

The pathogens causing flower diseases are fungi, bacteria, viruses, nematodes, mycoplasmas, viroids, parasitic seed plants and so on. Whether these pathogens damage flowers or not and the degree of damage depends on the pathogens, flowers themselves and external environmental conditions, so it can be known that "medication" alone can not completely control infectious diseases.

The disease will occur and spread only when pathogens, susceptible flowers and suitable environment exist at the same time; if there are susceptible flowers and pathogens in the greenhouse, but there are no suitable environmental conditions, the disease will not emerge. Therefore, the basic countermeasure of disease control is how to break this triangular relationship, so that the three can not emerge in the cultivation shed at the same time, such as reducing the density of pathogenic organisms or even completely eliminating, planting disease-resistant varieties, changing the cultivation environment and so on.

Effect of field operation management on disease control

Greenhouse management

Anthracnose and bacterial diseases often occur in high temperature and humid environment, while Botrytis cinerea occurs in cold and humid climate. Powdery mildew is more likely to occur in facility cultivation with poor ventilation. Therefore, the regulation of environmental factors such as temperature, relative humidity, ventilation, light, soil humidity and PH value in the cultivation shed is particularly important for the prevention and control of the disease.

Regular maintenance of ventilation and light transmission in the greenhouse is a very important external condition to restrain the occurrence of diseases. Even in the cold winter, the lateral membrane or window should be opened at noon every day to lower the humidity in the shed and the appearance of the plant, otherwise it will cause diseases in a large area by March, such as eye spot of carnation, leaf spot of carnation, gray mold of African chrysanthemum and so on.

Low light intensity makes plant overgrowth more susceptible to disease, summer shading to avoid the damage of strong light, but excessive shading will make the branches of flowers softer, light intensity should be controlled in the degree suitable for plant growth and development.

Plant management

The wound caused by transplanting and heart removal can become the entry point of bacteria. Pick the heart on a sunny day as far as possible to facilitate wound healing and avoid the invasion of pathogens. When carrying out cultivation operations such as heart picking and cutting, tools should be often disinfected to avoid spreading germs through fingers and tools as far as possible.

Reasonable adjustment of plant row spacing can effectively reduce the occurrence of diseases.

Irrigation management

Drip irrigation, furrow irrigation or water supply near the soil surface can effectively control the occurrence of diseases by avoiding the splash of irrigation water and bringing pathogenic bacteria or bacteria to healthy plants. Be careful not to allow water to stay on the petals or leaves. Although it is a very small amount of water, it is an important factor for most pathogens to germinate, invade plant tissues and breed. In addition, it is easy to cause burns if you encounter high temperatures in the hot sun.

Too high soil humidity will cause the decrease of soil water content and oxygen content, increase the concentration of carbon dioxide, and enhance the root damage caused by pathogens causing root rot, while the soil humidity is too low, and the seedling blight caused by Rhizoctonia is more serious. In addition, off-site cultivation is also a cultivation method to avoid the occurrence of epidemic disease.

Fertilization management

Plant growth needs nutrients, but the application of too much fertilizer causes damage to the plant, such as high EC value, plant yellowing and poor growth caused by fertilizer damage. The selection of fertilizer varieties varies according to flower varieties, and the nutrient requirements of different varieties of flowers will be different. The strength of plant growth will also affect the probability of disease occurrence.

Health management

Field sanitation can be said to be the easiest and most effective control strategy. Removing diseased plants, diseased leaves and weeds and taking them away from the cultivation field for destruction can reduce or even completely eliminate the density of pathogens in the field, and cannot deposit plant residues somewhere in the base and allow them to erode, because these residues will become hotbeds for the breeding of germs. rely on the wind to blow and splash, increase the chance of healthy plants to be susceptible to disease.

Once the pathogen of systemic diseases such as bacterial disease, virus disease or blight invades the plant, it is not easy to control. The whole plant of the susceptible plant (together with root zone soil or matrix) should be pulled out as soon as possible and taken away from the cultivation field to be destroyed. in order to avoid the spread of the disease. If only part of the branches and leaves of the emerging disease are removed, not only the goal of restraining the spread can be achieved, but the pathogen may be infected by pruning tools or root-to-root contact with nearby healthy plants. virtually, the pruning of diseased tissue is turned into pathogen vaccination, but the spread of the disease is accelerated. Besides, a clean cultivation environment is not only easy to manage, but also looks relaxed and happy.