Changes in flower yield, essential oil yield and oil composition after soil and foliage zinc and iron fertilization in German chamomile

Abstract

In order to analyze the effects of zinc (Zn) and iron (Fe) on growth, yield, oil production and oil quality of German chamomile, an open field experiment was conducted at the Research Center, CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Pantnagar, Uttarakhand, India in 2019–2020 and 2020–2021. The experiment was set according to Randomized block design (RBD) with 7 treatments and three replications. Treatments were as follow: T₁: control (without Zn or Fe fertilizers), T₂: Foliar Fe spray @ 0.5%, T₃: Foliar Fe spray @ 1.0%, T₄: Foliar Zn spray @ 0.5%, T₅: Foliar Zn spray @ 1.0%, T₆: Mixing of Zn in soil @ 30 kg/ha before transplanting, T₇: Mixing of Fe in soil @ 30 kg/ha before transplanting. Foliar spray of zinc (Zn) and iron (Fe) was conducted twice before flowering throughout the crop growth period. Obtained results showed that the plant height, canopy, number of flowers, fresh & dry flower yield, oil production, oil content and oil composition were radically increased and improved by foliar spray and soil mixing of Zn and Fe, compared to control. The maximum fresh flower & dry flower yield, oil content, and oil production were recorded in the treatment of foliar spray of Zn @ 0.5% followed by 1.0% in 2019–2020 and 2020–2021. The results also showed that Zn and Fe improved the oil quality and increased the concentration of major compounds like chamazulene, Z-spiroether, α-bisabolol oxide-A & B in oil compared with control.

Keywords:

• Essential oil
• foliar application
• German chamomile
• iron
• zinc

Acknowledgments

The authors are grateful to Director, CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Lucknow and Scientist In-Charge, CSIR-CIMAP, Research Center, Pantnagar for encouragement and imparting necessary facility and support to perform this work.

Disclosure statement

The authors report there are no competing interests to declare.