Hello. The symptoms observed on the leaves in the inserted pictures could be caused by a phytopathogenic disease, possibly bacteriosis, as well as by the attack of mites. In this case it is recommended to remove the severely affected leaves and carry out a first treatment with an insecticide-acaricide such as , in a dose of 5 ml/10 L water, applied by foliar spraying. To increase the effectiveness of the insecticide, it is recommended to add an adjuvant such as , in a dose of 2 ml/10 L to the solution. 7 days after this treatment, a second treatment with a fungicide such as , in a dose of 20 g/10 L water is recommended. It is advisable to spray the solutions as finely as possible, so as to achieve an even distribution on the plant, both on the underside and on the topside of the leaves, as well as on the stem. It is advisable to prepare a volume of solution corresponding to a single treatment (respecting the mentioned dosage), as the already prepared mixture does not have a shelf life longer than 24 hours. The treatments can also be applied to the other plants on the premises (if any). At the same time as the treatments are carried out, in order to provide the plant with the necessary nutrients and to revitalize it, it is also advisable to apply a fertilizer such as , by watering, according to the instructions on the product label.
If, after completion of the treatments, you still notice the presence of fine webs, 7-10 days after the completion of the second treatment, you may consider a third treatment with . Given the current condition of the plant, it is not possible to predict its future development.