Effect of Different Abiotic Stresses on Allium Cepa Plants: Results from a Field Study of Two Different Seasons

Abstract

Abiotic factors have the capacity to influence the nature and quantity of secondary metabolites. Alteration of environmental factors during plant growth can affect the production of bioactive phytoconstituents. A six-month field study was carried out in two different seasons to assess the effect of different abiotic stresses on bioactive compounds, i.e. flavonoids and phenols and plant yield of selected Allium species, i.e. Allium cepa L. (AC). (Family Amaryllidaceae). AC plants were grown for six months from November to April and for another six months from May to October on three different soil types (i.e. black, red, clay-loamy) and various stresses (salinity, water deprivation, flooding, fertilizer, metal, shade) were applied on the plants. At the end of the season, plants were collected, dried, and plant yield was determined. Hydroalcoholic extracts of all samples were prepared. Plant yield, TFC, TPC were determined in all the extracts. The results show varied response of AC plants to different soil types, stresses, and seasons. AC plants cultivated on red soil with fertilization give higher biomass yield in both seasons. AC plants grown in black soil under metal stress have highest TFC, TPC. Hence these conditions may be recommended for incorporation in cultivation practices of these valuable medicinal plants to ensure commercial supply of plants with higher phenol and flavonoid content and better plant yield.