For hydroponics studies in drought conditions using chickpea, polyethylene glycol (PEG 6000) is commonly used to induce osmotic stress, mimicking drought conditions. The concentration of PEG 6000 can vary depending on the severity of drought stress you aim to simulate, and different studies have reported varying concentrations.

Here are some typical concentrations from the literature:

The * depends on the level of drought stress you aim to induce. For chickpea, which is relatively drought-tolerant, a concentration between 5% and 10% PEG 6000 is often used to simulate moderate drought stress without causing excessive osmotic stress that could be detrimental to the plant's health.

You may want to experiment with these concentrations and adjust based on the physiological response of the chickpea plants, as response to PEG-induced stress can vary depending on the specific experimental setup and the genetic variability of the chickpea cultivar.

Thankyou Raghad Mouhamad for you reply. I am working on different varitieties of Chickpea lines so I should aim for moderate to terminal stress.