Agronomic interventions affect the growth, yield, and essential oil composition of German chamomile (Matricaria chamomilla L.) in the western Himalaya

German chamomile (Matricaria chamomilla L.) makes favourable use of environmental conditions when sown at the optimum time; however, less information is there in the literature about agronomic interventions in the Indian western Himalaya. Therefore, a field study was conducted for two successive years (2018-2019 and 20192020) to examine the effects of agronomic interventions on agro-morphological characters, essential oil (EO) yield, and chemical constituents of German chamomile cultivated in the Indian western Himalayan region. The experiment consisted of twelve treatments comprising of four sowing times (November 20, December 10, December 30, and January 20) in combination with foliar application of 3 salicylic acid (SA) levels (0 ppm, 25 ppm, and 50 ppm) replicated thrice in a factorial complete randomized block design (FRBD). Agro-morphological and yield characteristics were significantly higher in early sowing and SA applications but decreased with later sowing times. Days taken to develop each development stage declined with late sowing and vice-versa, while essential oil yield was 29.96 and 8.99% higher in early sowing (November 20) and 50 ppm SA application, respectively. Significantly higher alpha-bisabolol oxide A (5.80%) and bisabolone oxide A (14.74%) were recorded in late sowing (January 20) and early sowing time (November 20), respectively. The outcomes from the study presents innovative knowledge, a solution for farmers and industrialists to satisfactorily produce German chamomile by sowing at the proper time to get maximum yield and quality essential oil.

Automated summary

The study demonstrated that early sowing and salicylic acid (SA) application are beneficial for improving agronomic traits and yield of German chamomile in the Indian western Himalayan region, while these traits decrease with delayed sowing times. Additionally, sowing time and SA application influence the essential oil yield and chemical constituents of German chamomile.