Biochar effect on seed trigonelline content of fenugreek (Trigonella foenum-graceum L.) ecotypes under deficit irrigation

High demand for herbal medicines and the limited plant sources necessitates more research on these plants to increase their yield and effective compounds. The present study assessed the effect of biochar on yield and seed trigonelline content of fenugreek (Trigonella foenum-graceum L.) ecotypes under different irrigation regimes. Six branched fenugreek ecotypes including Dezful, Shushtar, Ardestan, Rehnan, Yazd and Khomeyni Shahr were treated by biochar application (at a rate of 7-8% of soil v/v) and non-application under two irrigation intervals of 4 (normal irrigation) and 8 (deficit irrigation) days using a split plot factorial experiment in a randomized complete block design with three replications. The study was conducted in the research field of Agricultural Biotechnology Research Institute of Iran in 2015. According to the results, biochar application increased the seed yield and biological yield under both irrigation intervals. The decreasing effect of increasing water intervals on seed yield, biological yield and trigonelline yield was observed in all ecotypes. Changes in seed trigonelline content did not follow a similar trend in different ecotypes. In summary, although biochar prevented the growth and yield reduction by decreasing water deficiency effects, itdid not have any significant effect on seed trigonelline content.