Fusarium Wilt Melon

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

Fusarium melon wilting was first discovered in the United States in 1931. Currently, you can meet with this ailment in a huge number of districts and regions. It is especially harmful in the territory of Central Asia, causing, in the event of a strong infection, crop losses of up to 60 - 70%, and sometimes even up to 92%. You can often encounter a similar nuisance in the Transcaucasus, as well as in the Volga region. The fungus, the causative agent of this scourge, is able to persist in the soil for several years, which significantly increases the harmfulness of fusarium wilting

A few words about the disease

Fusarium wilting can manifest itself at all stages of melon development. Most often, it is characterized by plant dwarfism, rapid drying of shoots and withering of leaves.

Melon roots and stems affected by fusarium wilt at first have a completely healthy appearance, although at the same time they often turn brownish, and root hairs gradually disappear on the roots. A little later, chestnut-brownish specks begin to form at the roots of the infected cultures. However, sometimes such spots may be absent - it all depends on the type of melons and the conditions for their cultivation. In places of the spots formed on the roots of plants, longitudinal stripes diverging up and down gradually appear, and their length in some cases can reach seventy centimeters.

Chlorotic spot is formed on the affected leaves, and chlorosis of the leaf blades often leads to their deformation. All leaves quickly lose their turgor.

In most cases, plants attacked by fusarium wilt die prematurely. And if the ill-fated disease begins to develop at the stage of fruit formation, then the fruits will not ripen. As for the fruits that have managed to develop normally on diseased plants, they lose their taste and become suitable only for livestock feed.

The most significant changes during the development of this harmful scourge are characteristic of the early stages of crop development, when they grow with greater intensity. In the phase of formation of the third to fourth leaves, the greatest water loss usually occurs.

The causative agent of fusarium wilt is a pathogenic fungus, the mycelium of which is located mainly in the vascular system of plants. And it can be preserved both on post-harvest melon residues and in the soil. The best temperature for the development of a pathogen is considered to be the range from twenty-three to twenty-five degrees, and the minimum temperature should not fall below twelve degrees. In this case, the optimal soil moisture should be in the range from forty to eighty percent of its total moisture capacity.

During the growing season, the spread of the harmful fungus occurs by micro- and macroconidia. The mycelium that has penetrated into plants is mainly concentrated in the vessels, provoking their blockage and subsequent intoxication. This explains the rather rapid wilting of plants. To a large extent, the development of the disease is facilitated by irrigation with cold water, low soil moisture and low temperatures (ranging from sixteen to eighteen degrees).

How to fight

The main measures to combat fusarium wilt of a melon are in a competent crop rotation, as well as in the breeding and selection of varieties resistant to the ill-fated disease.

It is advisable to try to bring the acidity of the soil to a mark of 6, 5 - this will help slow down the development of fusarium wilting. For the same purpose, nitrate nitrogen is also introduced into the soil.

It will also be useful to carry out a five-fold foliar feeding of growing melons with a 1.5% solution of ammonium nitrate or a 5% solution of superphosphate.

Before planting, seeds are dusted with "Trichodermin" or etched in "Baktofit" solution. And among biological preparations in the fight against fusarium wilting of melons, Planriz has proved itself quite well.