Investigation of the effect of some elements (B, Mo, Co and Pb) on growth, productivity and quality of Cymbopogon citratus L

摘要

Two pot experiments were conducted in Dokki, Egypt, during two successive seasons (1998/99 and 1999/2000) to study the effect of various levels of heavy elements, B (as boric acid at 20, 40, 60 and 80 ppm), Mo (as ammonium molybdate at 20, 40, 60 and 80 ppm), Co (as cobalt sulfate at 0.5, 1.0, 5.0 and 10.0 ppm) and Pb (as lead acetate at 5, 10, 15 and 20 ppm) on the growth, yield and chemical constituents of lemon grass (C. citratus). The different levels of B, Mo and Co promoted the vegetative characters including plant height, number of tillers, fresh and dry weight of herb. Pb caused unfavourable effect on most of the vegetative growth, specially at high levels (15 and 20 ppm). Total carbohydrates, crude protein, photosynthetic pigment and essential oil percentage recorded positive responses with various levels of B or Mo. However, application of Pb at 15 and 20 ppm led to marked decreased in the chemical constituents. The various effects of the application of these elements on the essential oil constituents, and macro- and microelement uptake of lemon grass are presented.