June 2007. Cucumbers in Vanuatu grow well for the first few weeks then begin to yellow, finally wither and die. They are sprayed routinely for pumpkin beetle, powdery mildew, downy mildew and anthracnose.
Pythium can kill young cucumbers if the soil is too wet, Fusarium rot (footrot) can be an issue and so can nematodes, wireworms or other beetle larvae. All these need to be considered.
Need also to consider nutrition, possibly K or Mg? However, the tomatoes in the background look quite green and healthy. The suggestion was to pull up a plant and check the root system. If the root system looks sound, then water the plants and apply fertilizer. If the foliage looks normal, then perhaps the K and to a lesser extent the Mg was being translocated.
Later, it was realised that the seeds used were originally hybrids, and perhaps the symptoms were due to replanting these a number of times, increasing susceptibility to (root) disease. Plants from a new batch of hybrid seed grew well.
|