Effect of Different Fertilizers on Crop Growth, Oil yield and Chemical Composition of Lemongrass (Cymbopogon citrates (DC.) Stapf)

Abstract

Purpose: Lemongrass (Cymbopogan citrates (DC) Stapf. ) is ranked among the top ten oil bearing crops in the world and the essential oils of lemongrass are widely used in pharmaceutical, cosmetics, food and fl avor, agriculture industries and possess an array of medicinal uses. Aromatic grasses respond well to application of manures and fertilizers. However, farmers do not use fertilizer. Therefore, it is very important to fi nd out the possibility to increase oil yield and improve the quality of essential oil by applying inorganic and organic fertilizer. Therefore, a study was conducted to investigate the eff ect of fertilizers on crop growth, bio mass production, oil yield and chemical composition of Lemongrass.Research Method: Three diff erent fertilizer mixtures (F1:compost only, F2: inorganic fertilizer (urea, triple super phosphate and muriate of potash at the rate of 278, 296 and 175kg/ha respectively) and F3: inorganic fertilizer + Compost) were used with (F0) control (without fertilizer). Randomized Complete Block Design (RCBD) was used as the experimental design. Number of leaves, tillers and plant height (cm) were recorded. Oil yield and chemical composition of fi ve months old plants were evaluated. Essential oil was extracted by hydro distillation and chemical composition of essential oil was analyzed by Gas Chromatography and Mass Spectrometry. Highest herbage yield (15.94 t ha-), dry matter yield (4.82 t ha-) and oil yield (fresh wgt. basis) (59.16 kg ha-) were recorded in the treatment of F3 (Compost 106.5g: Urea 2.96g: TSP 3.15g: MOP 1.86g per plant). Citral, β-Citral, Geraniol, α Pinene, cis -Verbenol were major chemical compounds identifi ed in oil. Findings: Research Limitations:The study focused on whether there were benefi ts of using organic and inorganic fertilizers for lemongrass cultivation. However, the research was done only for a limited number of fertilizer mixtures. Further research with diff erent fertilizer mixtures will off er most suitable mixture of fertilizers.Originality/Value: Present study revealed that, application of inorganic fertilizer along with compost result best growth performances and highest oil yield with high quantities of economically important major chemical constituents in lemongrass.

The effect of anaerobic digestate tea on the growth of lemon grass (Cymbopogan citratus)

“…An increase in leaf growth rate was also observed in another study conducted on the effect of fertilizers on the growth of the lemon grass. 29 Premathilake et al reported leaf numbers no higher than 65 leaves per plant at month 3 of their experiment with both the chemical and compost fertilizer used while at month 3 (12 weeks) of our experiment, the highest leaf number was 190 with respect to the 5.5 L m −2 digestate concentration and 60 for the lowest concentration of 0.6 L m −2 used. This could possibly be due to several parameters such as lower concentrations of nutrients in the fertilizers used in their study, the quality and nutrient content of digestate, levels of sunlight and air quality.…”

“…Furthermore, there was also no significant difference in the overall plant heights at the end of their 6 month experiment. 29 The results observed in our study can possibly be attributed to the supply of nutrients to the plants as provided by the digestate tea, where an increase in the nutrient supply resulted in an increase in growth rate. Increasing the amount of digestate tea beyond the 0.6 L m −2 application does not result in any further increase in the height of the plants as indicated in Fig.…”

“…Regardless of the fertilizer used, the lemongrass plants’ rate of growth increased steadily over 4 months, with a gradual decrease in rate thereafter. Furthermore, there was also no significant difference in the overall plant heights at the end of their 6 month experiment 29 …”

“…Similar observations were made by Premathilake et al . where they investigated the effect of both chemical and organic fertilizers on the growth of lemongrass plants, height being one of the growth parameters 29 . Regardless of the fertilizer used, the lemongrass plants’ rate of growth increased steadily over 4 months, with a gradual decrease in rate thereafter.…”

“…One interesting observation in particular is that at month 3, none of their tiller counts were over 12 regardless of the treatment used while in our study our lowest digestate concentration (0.3 L m −2 ) gave nine tillers and the highest (5.5 L m −2 ) gave 37 tillers. 29 This could be due to parameters outside of simple nutrient availability, such as temperature, humidity and general differences in the climates. This further highlights the importance of obtaining as much climate data as possible.…”