The Effect of Deficit Irrigation and Biochar on Quantitative and Qualitative Characteristics of Basil

Biochar as a soil amendment improves soil physical and chemical properties, increase nutrient availability, reduce nutrient leaching and ultimately increase crop production. Drought stress is one of the most important factors that limit plants growth. Arid lands have a little organic matter, and because of high pH, nutrients deficiency was observed in these soils. In order to study the effect of biochar on growth and concentration of nutrient in basil under water stress, one factorial experiment in Randomized Complete Block Design (RCBD) was carried out in Karaj, Iran. Experimental treatments included three levels of deficit-irrigation 100, 75 and 50% of water requirement of basil (a1, a2 and a3) and three levels of application of biochar 10, 5 and 0% by volume of each pot (b1, b2 and b3). The results of analysis of variance and comparison of the mean of measured traits (fresh and dry weight of leaves, stems and roots) showed that these traits were significantly different under the influence of different levels of irrigation and biochar application; So that the highest value of each of these traits was observed in treatment a1b1 and the lowest value was observed in treatment a3b3. The highest percentage of nitrogen (2.83 %) and phosphorus (0.16 %) was observed in the medium water stress treatment and the application of 10% by volume of biochar (a2b1) and the highest percentage of potassium (1.21 %) was observed in the a3b1 treatment. Also, the highest water productivity was obtained based on fresh (3.53 kg / m3) and dry (0.44 kg / m3) basil leaves in a3b1 treatment. Therefore, it can be concluded that the use of biochar in conditions of water stress has an effective role in improving nutrient uptake, which ultimately leads to increased vegetative growth and water productivity of basil.