Maataloustieteellinen Aikakauskirja Vol. 59: 25—29, 1987 Studies on fertilization of dill (Anethum graveolens L.) and basil (Ocimum basilicum L.) 11l Oil yield of basil affected by fertilization HÄLYÄ, S. Dept, of Horticulture, University of Helsinki, SF-00710 Helsinki, Finland Abstract. Basic fertilization and nitrogen top-dressing of basil was studied in 1984 and 1985 at the Department of Horticulture, University of Helsinki. The total N doses applied were 0, 0.2, 0.4, 0.8, 1.2 and 1.6 kg N/100 m 2. In 1984 the plants were of a mixture of different fenotypes and two of those formed 85 % of the crop-stand. In 1985 the variety grown was ’Budakalasz’. The optimum basic fertilization proved to be a compound fertilizer at the rate (NPK) of 0.4—0.16—0.68 kg/100 m 2. The content of volatile oils in dried herb ranged from 0.32 to 1.46 %. The total oil content was not significantly affected by fertilization except in 1984 when the fertilization decreased the oil content in the other of those two major fenotypes. Index words; calcium nitrate, compound fertilizer, basil nitrogen Introduction The general aim of the studies on fertiliza- tion of herbal plants has been the,optimizing of application level in respect to both the herb yield and aroma content and composition. The results found in different studies are, to some extent, conflicting. Pluck (1954) has stated that increase in fertilization will first increase the aroma content, and after a certain optimum level decrease that. The studies of Hornok (1980, 1983) on herb plants confirm this. On the contrary, Nykänen (1986) has found that nitrogen (N) application will first decrease and in larger doses increase the aroma production and also change the aroma composition. The edafic factors have been found to influence more the herb yield than the aroma, and in addition, having more ef- fect on the amount of the total aroma than on the composition of aroma causing com- pounds (Pluck 1954). Weichan (1948) has reported that the fer- tilization has minor effect on the aroma con- tent of basil. Ruminska (1978), instead, re- ported that increasing NPK-fertilizing will in- crease both thebasil yield and the amount of the volatile oils. Wahab and Hornok (1981) 25 JOURNAL OF AGRICULTURAL SCIENCE IN FINLAND https://www.c-info.fi/en/info/?token=N25tZWwHeEz3cuCm.Gz0jj5eaKNG84zQ61UvWCw.zXf0Jw8FHo-Ns9sTtLg5kwr8Vrb8QwSsF0T7jVyQ4x7GgnAPG7FXsoInaks2dlmIyoO5QkiLBkBSyTu6k_82h2f6F8FnFRN-c2rsBRO3NVYFLR3RSZtqWIgi_Ql41oDgeBU2DxWeO3OxmSqo9g-svUz8fTh5dWpO5omkLdsCdf0t stated, according to the studies carried out in Hungary, that the rates of 1.2—1.0—1.0 kg NPK/100 m 2 give the best result in respect to both the herb yield and aroma of basil. Later Hornok (1983) found that K is of minor im- portance and the optimum dose of NPK was higher, 2.4—1.5—1.2 kg/100 m2 . N de- creased the linalool content, and K instead, increased the contents of linalool and estragol. The effects of fertilization of herbal plants have been mostly studied in Middle Europe. Research in this field is necessary also in northern conditions especially now that there is a growing interest in herb production in Nordic countries. A study on the effects of different levels of basic fertilization and N top-dressing on basil was carried out in two successive years (1984—85) in Finland. The ef- fects on both the herb yield and aroma was studied. The detailed results on herb yield are reported separately (Hälvä and Puukka 1987). greenhouse, was transplanted into the open- field after a month in spacings of 20 x 25 cen- timeters. The crops were grown using general farming practices and harvested at the begin- ning of flowering (Hälvä and Puukka). The amount and composition of aroma compounds in dried herb were analysed by the method of head space gas chromatography as described by Hiltunen et ai. (1985). In 1984 the fresh samples were also determinated by high resolution gas chromatographic mass spectrometry (Nykänen 1986). The results on herb yields and nitrate concentrations (1984) are published separately by Hälvä and Puuk- ka (1987). The field trials were set up according to the method of completely randomized blocks with four replications and plots of 3 m 2. The data was studied by analyses of variance and re- gression. The means were separated by Tu- key’s HSD or Student-Newman-Keuls’s mul- tiple range tests (Steel and Torrie 1980). Materials and methods The effect of fertilizing on the herb yield of basil was studied during 1984 and 1985 at the Department of Horticulture, in the Uni- versity of Helsinki. Five treatments including the unfertilized control were applied in 1984. The soil, humous fine sand, was fertilized by 4 kg/100 m 2 compound fertilizer (NPK 10—4—17) before planting basil. The nitrogen top-dressing by calcium nitrate (NO3 -N 16, Ca 20) was broadcast two weeks later, except the largest dose which was split in two appli- cations. The first one was applied two weeks after planting and the second one after two more weeks. The total nitrogen rates were A: 0, C: 0.4, D: 0.8, E: 1.2 and F: 1.6 kg/100 m 2. In addition, in 1985 a treatment of B: 0.2 kg N/100 m 2 by the compound fertilizer (10 —4—17) was applied before planting (Hälvä and Puukka 1987). In 1984 the basil seeds were of a mixture of several chemotypes, and in 1985 the variety grown was ’Budakalasz’. Basil, started in a Results The basil plants in 1984 consisted of six clearly different fenotypes two of which were of the majority. Those with either violet flowers and thin, light green leaves (fenotype 1) or those with white flowers and thick, shiny leaves (fenotype 2) formed 85 % of the total crop stand and the results of these were anal- ysed separately. The contents of volatile oils ranged from 0.32 to 1.46 % in 1984, and from 0.93 to 1.14 % in 1985 (Fig 1). The fertilization had significant (p< 0.05) effect only on the oil con- tent of fenotype 2: the total oil content in the herb decreased the more fertilized the crop was. The response to nitrogen application is presented in Figure 2. The oil composition was not affected by the fertilization. The oil content was significantly (p<0.01) higher in the herb of fenotype 1 than in feno- type 2. The highest figure was reached with the smallest fertilization application (0.4 kg N/100 m2) and the lowest one with the 26 largest application (1.6 kg N/100 m 2) (Fig 1). Compounds methyl chavicol (estragol), lina- lool, /3-caryophyllene and eugenol were in highest amounts among the 14 compounds identified. The oil composition of the two major fenotypes was clearly different. Feno- type 1 was of methyl chavicol-type, and lina- lool and eugenol were in highest amounts in fenotype 2 (Table 1). In 1985 there were no significant differences in aroma content of the variety ’Budakalasz’ Table 1. The main compounds in the volatile oils of basil herb in 1984—85 according to the fertilization treatments. TRIAL/ A B C D E F F-values» compound ' abc FENOTYPE 1/1984 Methyl chavicol 68.6 75.9 75.3 73.8 78.6 2.22 271.5“* 0.63 j3-caryophyllene 6.6 7.2 5.1 4.9 5.2 0.48 2.0 1.22 Germacrene-D 4.7 3.6 3.2 3.2 3.5 1.26 0.2 0.96 Borneol 1.7 1.2 1.2 1.4 1.4 1.07 24.0*“ 0.27 1.8- 2.0 2.4 1.9 1.9 1.6 0.54 0.1 1.60 Eugenol 0.7 0.3 0.2 0.0 0.0 3.36 63.7*“ 2.03 Linalool 0.3 0.4 1.3 0.1 0.0 1.79 477.2“* 1.73 FENOTYPE 2/1984 Methyl chavicol 2.1 19.0 20.5 16.8 14.7 (3-caryophyllene 5.0 4.1 4.0 6.0 5.3 Gerraacrene-D 3.5 4.0 2.8 3.3 3.8 Borneol 3.3 2.4 2.5 2.1 3.1 1.8- 1.9 1.8 2.1 1.3 2.5 Eugenol 3.5 4.0 2.8 3.3 3.8 Linalool 46.7 34.7 38.8 40.7 33.9 ’BUDAKALASZ’/1985 Linalool 57.4 56.8 55.8 59.4 59.6 58.5 0.18 Eugenol 14.6 13.6 12.5 11.6 10.9 9.1 0.55 Thymol 5.8 5.8 5.9 5.1 6.4 6.9 1.20 Methyl chavicol 4.1 3.4 3.8 3.9 4.8 4.6 1.31 j3-caryophyllene 1.6 1.4 1.5 1.5 1.5 1.3 0.22 1.8- 1.2 1.2 1.1 1.3 0.8 0.9 0.68 7-terpinene 0.4 0.3 0.6 0.4 0.3 0.3 0.72 * 1984: F(4,12) a = fertilization, F(l,15) b = fenotype, c = interaction 1985: F(5,23) a = fertilization Fig. I. Volatile oil contents in basil herb affected by ni- trogen application (1984: fenotypes 1 and 2, 1985 ’Budakalasz’). Fig. 2. Response of the volatile oil contents (fenotype 2) to the nitrogen applications (1984). 27 caused by basic fertilization, calcium nitrate top-dressing or nitrogen. The main compounds in the oil were linalool and eugenol as presented in Table 1. Two components found in traces only, /3-pinene (r= —0.701 + ++) and myrsene (r = —0.532+ +), were affected by thefertilization doses applied the contents of both of these compounds decreased with the increase in nitrogen application. The meth- yl chavicol content slightly increased with ni- trogen fertilization (r =0.407 + ). Discussion The optimum fertilization application for basil in the Finnish climate on a soil in good nutritional condition proved to be a basic fer- tilization at the rate of 0.4—0.16—0.68 kg NPK/100 m 2 which is smaller than what has been reported in southern countries. In the north low temperatures and a short growing season restrict the growth of cold-sensitive plants like basil. These plants must be first grown in greenhouses and later transplanted out-of-doors shortening thus the growing pe- riod in the field. Accordingly, less fertilization is needed outdoors than in the southern con- ditions. The average volatile oil content and com- position were not considerably affected by the fertilization applied. The plants without fer- tilization had the highest amount of the vola- tile oils. Nykänen (1986) also found the highest total oil contents in the herbs grown without fertilization. The comparison between the results in different studies is most com- plicated because of different analysing meth- ods. In addition, the variation between the contents of the individual samples in the above mentioned report was extremely wide, and the conclusions on the effect of fertilization re- mains indistinctive. Neither the two main fenotypes were separated in the work of Ny- känen (1986), and the oil was thus named linalool-estragol while in the present study fenotype 1 was found to be of estragol-type and fenotype 2 of linalool-eugenol-type. The decrease in the volatile oil content (fenotype 2) by increase in fertilization con- flicts with the results reported by Ruminska (1978) and Wahab & Hornok (1981) who have stated that increasing fertilization will also increase the aroma. Many scientists like Guenther (1949), Gildmeister and Hoff- mann (1961) and Jansen (1981) have reported earlier on the differentoil composition of dif- ferent basil chemotypes. This feature stresses the importance of plant breeding and variety testing of herb plants. Basil with significant amount of linalool and estragol or just estra- gol are preferred by the food industry (Zola and Garnero 1973). Acknowledgements. The author wishes to thank Lee- na Puukka and Heikki Vuorela for the technical assist- ance. The work was supported by the Academy of Fin- land and the Tiura foundation. References Pluck, H. 1954. The influence of the soil on the content of active principles in medicinal plants. J. Pharmacy Pharmacology 6: 153—163. Gildmeister, E. & Hoffman, F. 1961. Die Äterischen Ole, 7. 806 p. 4. Aufl. Berlin. Guenther, E. 1949. The Essential Oils, 3. 777 p. New York. Berlin. Hiltunen, R., Vuorela, H. & Laakso, I. 1985. Quanti- tative head space gas chromatograpy in the analysis of volatile oils in aromatic plants. Baerheim Svend- sen A. & Scheffer, J. J. (Eds). Essential oils and aro- matic plants, pp. 23—41. Dordrecht. Hornok, L. 1980. Effect of nutrition supply on yield of dill (Anethum graveolens L) and the essential oil con- tent. Acta Hort. 96, 1: 337—342. —, 1983. Influence of nutrition on the yield and content of active compounds in some essential oil plants. Acta Hort. 132; 239—247. Halva, S. & Puukka, L. 1987. Herb yield of dill and basil affected by fertilization. (In press). Jansen, P.C.M. 1981. Spices, condiments and medicinal plants in Ethiopia, their taxonomy and agricultural significance. Agric. Res. Rep. 906: 1—326. Nykänen, I. 1986. High resolution gas chromatographic 28 mass spectrometric determination of the flavor composition of basil (Ocimum basilicum L.) cultiva- ted in Finland. Z Lebensm. Unters. Forsch. 182: 205—211. Ruminska, A. 1978. Der Einfluss der Diingung auf den Wirkstoffgehalt und den Ertrag von Heil- und Gewiirzpflanzen. Acta Hort. 73: 143—164. Porter, N.G., Shaw, M.L., Shaw, G.J. & Ellington, P.J. 1983. Content and composition of dill herb oil in the whole plant and the different plant parts dur- ing crop development. New Zeal. J. agric. Res. 26: 119—127. Singh, R.S. 1971. Influence of soil salinity on produc- tion of seeds and essential oil content of dill (Anethum graveolens L.). Indian Oil Soap J. 36: 243—245. Singh, R., Singh, L.B. & Singh, C.P. 1971. Response of N and P on yield and essential oil content of dill in non-saline alkali soils. Fertilizer News. 16: 48—49. Steel, R.G.D. & Torrie, J.H. 1980. Principles and pro- cedures of statistics, a biometrical approach. 633 p. New York. SELOSTUS TILLIN JA BASILIKAN LANNOITUS 111 Lannoituksen vaikutus basilikan öljysatoon. Häivä, S. Helsingin yliopisto , Puutarhatieteen laitos, 00710 Helsinki Basilikan lannoitusta tutkittiin vuosina 1984 ja 1985 Helsingin yliopiston puutarhatieteen laitoksella. Kokeis- sa selvitettiin peruslannoituksen (NPK 10—4—17) ja kalk- kisalpietarina annetun typpilisän (N03—N 16, Ca 20) vai- kutusta basilika satoon ja haihtuvan öljyn määrään ja koostumukseen. Vaikutukset yrttisatoon raportoidaan erikseen (Hälvä jaPuukka 1987). Kokonaistyppimäärät olivat 0, 0.2, 0.4, 0.8, 1.2 ja 1.6 kg N/100 m 2, Peruslan- noitteet (Puutarhan Y3), 0.2 ja 0.4 kg N/100 m 2, levi- tettiin ennen basilikan istutusta ja lisälannoitteet annet- tiin kahden viikon kuluttua, paitsi suurin erä, joka an- nettiin kahdessa osassa kahden viikon välein. Sato korjattiin juuri basilikan kukinnan alkaessa. Haih- tuva öljy analysoitiin Helsingin yliopiston farmasian lai- toksella kaasukromatografisesti head space -menetelmällä. Vuonna 1984basilikakasvusto koostui pääasiallisesti kah- desta muista selvästi poikkeavasta fenotyypistä, joiden haihtuvan öljyn määrä oli 0.32—1.46 °7o. Toinen näistä oli pääkomponenttien mukaan estragoli-tyyppiä ja toi- nen linaloli-eugenolityyppiä. Vuonna 1985 viljelty lajike oli ’Budakalasz’. Sen öljypitoisuus oli00.91.143 —1.14 % ja koostui etupäässä linalolista ja eugenolista. Lannoitus vaikutti merkitsevästi vain toisen fenotyy- pin öljypitoisuuteen: sen määrä väheni sitä mukaa kuin lannoitusta lisättiin. Lannoitus ei muuttanut basilikan öl- jynkoostumusta. Fenotyyppien öljypitoisuudet poikke- sivat huomattavasti toisistaan. Tästä syystä maustekas- vien lajikejalostukseen tulisi lisätä huomiota, sillä vain harvoista lajeista on olemassa lajikkeita. 29