Problems in soilless (cocopeat) cucumber

Question

We are cultivating seedless cucumbers in Cocopeat Growbags under polyhouses, as the soil is heavily infested with root knot nematodes.

We had noticed that our plants have started increasingly showing abnormal growth (it is increasing/spreading), photos attached. We are noticing that the leaves become dark green and start bunching on top together. We have tried treating with excess boron and micro-nutrients, but the problem is spreading. We have shown it to local experts but they have been unable to identify the issue. Can someone advise as to whether the issue is a nutrient problem or some disease??

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Answer 1

The main causes of growth distortions in plants are viruses, herbicide/toxin damage, and specific nutrient deficiencies. There are several viruses that affect cucumbers, listed in this article:
http://vegetablemdonline.ppath.cornell.edu/factsheets/Viruses_Cucurbits.htm
Check whether anyone around you could be spraying herbicides or other toxic chemicals.
You have probably already looked into or treated for zinc or copper deficiency, but if not, those are possibilities:
http://agropedia.iitk.ac.in/content/deficiency-symptoms-nutrients-and-their-remedies-cucumber