Why do tomatoes get black spots at the blossom end?
This trouble is called blossom-end rot. It is not caused by a definite disease organism, but seems to be physiological in its nature- a failure of moisture to reach the tender tissues at the blossom end. The trouble may be due to a lack of rainfall, droughty soil, or alternating dry and wet spells. The trouble is often followed by secondary mold or fungus infection. It sometimes occurs when the soil is not particularly dry, either because the root system is defective or because there is not enough oxygen in the soil for proper moisture intake. Control is by any measure that ensure adequate water supply, such as irrigation, maintaining organic matter in soil; in some cases, improved drainage.
What is meant by “resistant” varieties of tomatoes?
These varieties have been bred to resist the attack of the common fusarium wilt. They are attacked by the disease but do not succumb to it. There are no immune varieties. Among the resistant varieties are varieties that are identified by the initials VFN and VF. All are highly resistant. Those with an N are resistant to nematodes.
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