Nitrogen, phosphorous and potassium levels affected growth indices, leaf gas exchange parameters and biomass production of henna (Lawsonia inermis L.) ecotypes

Lawsonia inermis L., with medicinal and industrial applications, belongs to the family of Lythraceae and grows in warm and arid regions. This study was carried out to explore the effects of nitrogen (urea; N), phosphorous (single superphosphate; P) and potassium (potassium chloride; K) fertilizers (N: P: K, 0:0:0, 100:50:50, 200:100:100, 300:200:150 kg ha(-1)) on photosynthesis and growth of three henna ecotypes (such as Shandad, Roodbar and Bam) in Kerman and Shandad climatic conditions. The obtained results showed that photosynthesis parameters, some growth indices and biomass production improved with increase in fertilizer levels. The highest values of leaf gas exchange parameters including net photosynthesis rate, leaf stomatal conductance, and transpiration rate were obtained from Shandad ecotype. The net photosynthesis rate, leaf area index, crop growth rate, specific leaf weight, leaf area duration, biomass duration, and dry matter production were further in climatic conditions of Shandad. The most important variables that significantly affected henna leaf production were transpiration rate (in climatic conditions of Shandad) and biomass duration (in both of Kerman and Shandad climatic conditions).