In summerdark spots appear on walnut leavesSuch spots can also be seen on ripening walnut fruits. When the nuts mature, the skin does not crack, but the black one sticks and dries up.The nuts on the tree are black and the inside is rottingDo you have this walnut problem too? Seewhy walnuts turn blackand how to deal with it!
Why do walnuts turn black?
Fig. 1945irenka, forum.PoradnikOgrodniczy.pl
The blackened and rotting fruit of a nut cannot be saved anymore Such nuts cannot be eaten. Therefore, during the harvest, it is necessary to review the fruits and discard the blackened ones. Fortunately, there are always a lot of he althy nuts that we can enjoy: -)
We can and must save the whole tree, becauseblackening and rotting of nutscan be caused by two serious diseases
The first iswalnut anthracnoseIt is caused by the fungus Gnomonia leptostyla. Symptoms of this disease are most often observed on the leaves and fruits of the walnut. Yellow spots appear on the leaves, mainly between the veins, which then darken until the leaf finally turns brown and dries up. Infected leaves may fall prematurely from trees in autumn.
Similar stains also appear on walnut fruit, often concentrated on one side of the fruit.Nuts with black spots do not mature and fall offStains may also appear on walnut shoots.
Very similar symptoms are caused by another disease, which is easily confused with anthracnose.It is thewalnut blotchcaused by the bacterium Xanthomonas campestris pv. juglandis. In the case of bacterial blotch, however, we will not observe the white bloom of mycelium within the spots, which is usually associated with anthracnosis. The stains that appear will also be a bit smaller.
It is also worth looking at the walnut shoots. In the case of anthracnose, spots appear on the shoots, which darken with time.In the case of bacterial blotch, streaks do not appear on the shoots, but rather streaks .
In both cases, it is necessary tocut shoots with symptoms ofinfection, especially the branches most severely affected by the disease. It is also extremely importantraking and removing leaves that have fallen under the walnut , because it is on the leaves that the pathogen winters and then re-infects the tree in the spring.
Spraying is also necessary . We fight bacterial disease with the use of Miedzian 50 WP and Miedzian Extra 350 SC. The tree should be sprayed twice, at two-week intervals, from the moment of bud break to flowering.female flowers.
In the case of walnut anthracnose, Miedzian will also be helpful. The firstspraying with Miedzian against anthracnose is carried out at the beginning of May, as soon as the first developed leaves appearThe second one just before the flowering of female flowers.
Spraying against blackening of walnuts
Fig. Target
Apart from Miedzian, it is also worth spraying with the fungicidal agent Signum 33 WG. We can use it from the beginning of the flowering phase until the end of the fruit development phase, by spraying two sprays with an interval of 14 days.
All the above-mentionedpreparations against walnut diseasescan be ordered in our store tutorial. We guarantee an attractive price and fast shipping. To view the offer, press the button below.
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