Thanks a million. I think this problem is not related to lack of calcium. Because lack of calcium causes blossom end rot in fruits. As you see, these cankers have been caused in the middle of the fruit.
Hi Elaheh: When the problem is common in the field that mean its is environmental or physiological problem, but when the infections is as spot area in the field that mean mostly, the causal agent is pathogen.
and you can direct test by microscopic to confirm if it is an anthracnose
I think that boron deficiency which can promote the occurrence of anthracnose. Boron is an essential element for welding the carpel during fruit development.
I am afraid I didnt understand your mean. Do you think if this problem is related to boron deficiency or anthracnose or both of them?
Dr Athayde, As you know anthracnose disease cant establish on the leaves of plant but if leaves of plant is Infected by colletothricum, it must be seen on the older leaves. is it true?
on the other hand, the symptom of boron deficiency must be seen on the younger leaves of plant.
Do you think if this method is a way to help we diagnose the cause of this problem?
Hi, in most cases these symptoms on tomato fruits are associated with low temperatures during flowering and fruit set or virus infection. Boron and calcium deficiency is reflected in the blossom end rot.
My first bet is boron defficiency, usually responsible for healed cracks exposing the placenta and the seeds. Water supply, temperature and nutritional balance probably predispose the plant to this disorder. I do not think there is any biotic agent involved. The distribution of affected plants is an aid to a precise diagnostic. General distribution in the field suggests a physiological disorder in contrast to a virus disease, for example.
Elaheh, do know the soil characteristics? Boron deficiency made worst by:
sandy soils, alkaline soils, soils low in organic matter, high levels of nitrogen and high levels of calcium. Have you noticed there are other symptoms?? With severe boron deficiency, the growing points of main shoot and laterals die. The younger leaves remain small, are curled inwards and deformed. They show chlorotic spots between the veins which are yellow to orange and the veins themselves can become yellow or purple. The older leaves appear yellowish green.