Munnu Singh

Herbage, oil yield and oil quality of patchouli [Pogostemon cablin (Blanco) Benth.] influenced by irrigation, organic mulch and nitrogen application in semi-arid tropical climate

A field experiment was conducted during 1999 and 2000 at Bangalore in the semi-arid tropical climate of South India, to study the influence of irrigation, organic mulch and nitrogen application on its growth, herbage, oil yield and quality of patchouli [Pogostemon cablin (Blanco) Benth.] grown on Alfisol. Irrigation at 1.0 IW:CPE ratio (irrigation water:cumulative pan evaporation), 5 t ha−1 distilled waste material of palmarosa, or 200 kg N ha−1 produced maximum herbage and oil yields. Organic mulch reduced weed biomass significantly. The oil content varied from 0.61 to 0.73%. The highest oil content was recorded with irrigation at 0.8 IW:CPE ratio, no mulch and 100 kg N ha−1. The quality of the essential oil with 50.66–54.31% patchouli alcohol, 9.86–10.26% α-bulnesene and 4.27% α-patchoulene was found to be good and readily accepted in the market.

Effects of N and K on growth, herbage, oil yield and nutrient uptake patterns in rosemary (Rosmarinus officinalis L.) under semi-arid tropical conditions

Summary Essential oil of rosemary (Rosmarinus officinalis L.) possesses good olfactory properties and is suitable for use in perfumes, soaps and fragrances. Field experiments were conducted over 2 years (2003-2005) in an area experiencing a semi-arid tropical climate, to study the influence of two N levels (150 or 300 kg N ha–1 year–1) and three K levels (41.5, 83.0 or 124.5 kg K ha–1 year–1), or no fertiliser, on the growth, herbage and oil yields and nutrient uptake patterns of rosemary. The results showed that application of 300 kg N ha–1 year–1 produced higher herbage and oil yields in rosemary, compared with 150 or 0 kg N ha–1 year–1. The application of 83.0 kg K ha–1 year–1 produced maximum herbage and oil yields, compared with 0 or 41.5 kg K ha–1 year–1. Total N and K uptake levels were increased significantly by the application of N and K. Nitrogen uptake increased by 85.2% and 137.7%, and K by 80.9% and 123.9%, respectively, with the application of 150 or 300 kg N ha–1 compared to controls (no N). Similarly, N uptake increased by 96.1%, 130.2% and 113.6%, and K by 79%, 124.3% and 110.4%, respectively, with the application of 41.5, 83.0, or 124.5 kg K ha–1 compared to controls (no K). Oil content and oil composition were not influenced by nitrogen or potassium levels.

Effects of plant spacing, fertilizer, modified urea material and irrigation regime on herbage, oil yield and oil quality of rosemary in semi-arid tropical conditions

Summary Field experiments were conducted in an area experiencing a semi-arid tropical climate to study the influence of plant spacings (45 30 cm, 45 45 cm and 45 60 cm), fertilizer levels (0, 10 t vermicompost, 5 t vermicompost + 150 : 25 : 25 kg N, P, K ha–1) and 300 : 50 : 50 kg N, P, K ha–1, modified urea material (Prilled urea and 20% (DCD) coated urea) and three soil moisture regime (0.25, 0.50 and 0.75 IW : CPE ratios – IW is the depth of irrigation water and CPE was the cumulative pan evaporation) on herbage, oil yield, oil content and oil quality of rosemary. Results revealed that closer plant spacing of 45 30 cm, application of 300 : 50 : 50 kg N, P, K ha–1, DCD coated urea and irrigation at 0.50 IW : CPE ratio produced maximum herbage and oil yields of rosemary. Content and quality of oil were not influenced by plant spacing, fertilizer or irrigation regime.

Long-term studies on yield, quality and soil fertility of lemongrass (Cymbopogon fiexuosus) in relation to nitrogen application

SummaryA field experiment was conducted over five years (1992–97) at Bangalore (13.58N, 77.558E, 930.m above mean sea level) to study the effect of nitrogen application (0, 50, 100 and 150.kg N ha–1 year–1) on yield, oil quality and soil fertility of lemongrass (Cymbopogon fiexuosus) in the semi-arid tropical conditions of South India. Fresh herbage yield of lemongrass differed significantly between years; the yields increased up to the second year after which they started to decline. During the five years, the response to nitrogen was linear, while still maintaining the same content and quality of essential oil. The oil content and chemical composition of oil did not change as the crop aged. Application of nitrogen and phosphorus maintained the fertility of the soil while potassium depletion was noticed.Summary A field experiment was conducted over five years (1992–97) at Bangalore (13.58N, 77.558E, 930.m above mean sea level) to study the effect of nitrogen application (0, 50, 100 and 150.kg N ha–1 year–1) on yield, oil quality and soil fertility of lemongrass (Cymbopogon fiexuosus) in the semi-arid tropical conditions of South India. Fresh herbage yield of lemongrass differed significantly between years; the yields increased up to the second year after which they started to decline. During the five years, the response to nitrogen was linear, while still maintaining the same content and quality of essential oil. The oil content and chemical composition of oil did not change as the crop aged. Application of nitrogen and phosphorus maintained the fertility of the soil while potassium depletion was noticed.

Effects of nitrogen, phosphorus and potassium on herbage, oil yield, oil quality and soil fertility status of lemongrass in a semi-arid tropical region of India

Summary Field experiments were conducted in an area experiencing a semi-arid tropical climate at Bangalore, India. The effects of phosphorus (at 0, 17.75 and 35.50 kg ha–1 year–1), potassium (at 0, 33.2, 66.4 and 99.6 kg ha–1 year–1) and, in another experiment, nitrogen (at 100 and 200 kg ha–1 year–1) and potassium (at 0, 33.2 and 66.4 kg ha–1 year–1) were studied on herbage and oil yield of lemongrass [Cymbopogon flexuosus (Steud.) Wats.] and on soil fertility status. The results revealed that application of 200 kg N ha–1, 35.50 kg P ha–1 and 66.4 kg K ha–1 produced significantly higher lemongrass herbage and oil yields compared with controls. The content and composition of the oil were not influenced by N, P and K application. Soil fertility status was maintained by the application of fertilisers compared with soil in control plots.

Effect of soil moisture regime, nitrogen and modified urea materials on yield and quality of geranium (Pelargonium graveolens) grown on alfisols

Two field experiments were conducted during 1996–98 at Bangalore, India to study the effect of soil moisture regimes (0·3, 0·6 and 0·9 IW:CPE ratios) irrigation water:cumulative pan evaporation (IW:CPE) ratios and three rates of nitrogen application (0, 100 and 200 kg/ha) and in another experiment, three soil moisture regimes (0·3, 0·6 and 0·9 IW: CPE ratios), two rates of nitrogen application (100 and 200 kg/ha) and modified urea materials [prilled urea (PU) and dicyandiamide coated urea (DCDCU)] on oil content, herbage, oil yield and quality of geranium grown on altisols. Soil moisture maintained at 0·6 IW:CPE ratio significantly increased the herbage and oil yields of geranium. Application of 200 kg N/ha gave the maximum herbage and oil yield compared with those obtained from 0 and 100 kg N/ha. DCDCU produced higher yield than PU. The concentration and quality of essential oil were not influenced either by soil-moisture regime, rates or carriers of N.

Effect of irrigation and nitrogen on herbage, oil yield and water use of lemongrass (Cymbopogon flexuosus) on alfisols.

A field experiment was conducted with lemongrass ( Cymbopogon flexuosus ) at Bangalore, India during 1993–95 under three oil moisture regimes (0·75, 0·50 and 0·25) irrigation water:cumulative pan evaporation (IW:CPE) ratios and four rates of nitrogen application (0, 50, 100 and 150 kg ha −1 ). The soil moisture regime maintained at 0·75 IW:CPE ratio significantly increased crop growth characters such as plant height, leaf area index, herbage and essential oil yields, compared with those having 0·25 and 0·50 IW:CPE ratios. An application of 100 kg N ha −1 was found to be optimal for crop yield. Oil content and quality of oil were not affected by irrigation and nitrogen rates.

Effects of nitrogen, potassium and soil moisture regime on growth, herbage, oil yield and nutrient uptake of South American marigold (Tagetes minuta L.) in a semi-arid tropical climate

Summary Two field experiments were conducted between 2001 and 2003 to study the effects of different nitrogen levels (0, 100 and 200 kg N ha–1) and potassium levels (0, 41.5 and 83.0 kg K ha–1) and, in a parallel experiment, soil moisture regimes [0.25, 0.50 and 0.75 irrigation water:cumulative pan evaporation (IW:CPE ratios)] and three nitrogen levels (0, 100 and 200 kg N ha–1) on growth, herbage, oil yield and nutrient uptake of South American marigold (Tagetes minuta L.). The application of nitrogen at 200 kg ha–1 significantly increased plant height, fresh weight, leaf/stem ratio, leaf + flower/stem ratio, herbage (biomass) yield, oil yield, oil content, and N, P and K uptake compared to controls without nitrogen fertiliser. Plant height, herbage yield, oil yield, and N, P and K uptake increased significantly at 83.0 kg K ha–1 compared to controls without K fertiliser. A soil moisture regime at an IW:CPE ratio of 0.5 significantly increased herbage, oil yield and nutrient uptake compared with an IW:CPE ratio of 0.25. Oil quality was not influenced by N, K or soil moisture regime.

Irrigation and Nitrogen Requirement of Lemongrass [Cymbopogon flexuosus (Steud) Wats] on a Red Sandy Loam Soil under Semiarid Tropical Conditions

Abstract A field experiment was conducted with lemongrass [Cymbopogon flexuosus (Steud) Wats] cv. Cauvery at Bangalore, India, during 1993-94 to study the effect of three soil moisture regimes (0.80, 0.53 and 0.40) irrigation water: cumulative panevaporation (IW:CPE) ratio and four levels of nitrogen (0, 50, 100 and 150 kg/ha). Soil moisture regimes maintained at 0.80 IW:CPE ratio significantly increased crop growth, herbage and essential oil yields as compared with those having 0.40 or 0.53 IW:CPE ratio. Application of 100 kg N/ha was found to be the best with respect to the yield of the crop. Quality of the essential oil in terms of its two major constituents, citral and geraniol were not affected by soil moisture regimes or nitrogen application. Oil content was not affected by soil moisture regime or nitrogen application. It was concluded that lemongrass should be irrigated at 0.80 IW:CPE ratio with an application of 100 kg N/ha in the semiarid tropical region of India.

Relative efficiency of prilled urea and urea-supergranules in Java citronella (Cymbopogon winterianus Jowitt)

A two-year field study was carried out to compare the efficiency of prilled urea and urea-supergranules in the cultivation of a perennial aromatic grass, citronella (Cymbopogon winterianus Jowitt) in a sandy loam soil. Application of 300kg Nha−1 year−1 increased the herb and essential oil yields. Urea-supergranules significantly increased the yields over prilled urea.