Initial studies on seed oil composition of Calendula and Lunaria R. J. Martin, N. G. Porter and B. Deo New Zealand Institute for Crop & Food Research Ltd, Private Bag 4704, Christchurch. Abstract Two arable oil seed crops, Calendula officinalis (calendula or pot marigold) and Lunaria annua (lunaria or honesty), were evaluated for their oil yield and composition in three preliminary trials at Lincoln. Fourteen cultivars of calendula had oil yields of c. 15%, with calendic acid ester levels ranging from 25 to 50%. As the calendula seed heads matured, seed size, oil content and calendic acid content of the oil all increased. Lunaria produced seeds with 30-35% oil, containing 21- 44% erucic acid and 6-20% nervonic acid. Additional key words: Calendula officinalis L., calendula, marigold, honesty, Lunaria annua L., seed yield, flower yield, calendic acid. Introduction binder in paints, coatings and cosmetics There is considerable worldwide (Muuse et al., 1992). A previous trial (Martin industrial interest in sourcing a range of fatty and Deo, 2000) looked at agronomic acids with specific properties from renewable production of calendula, but oil content of the resources, especially plants, for conversion seed was not measured. into value-added products such as lubricants, polymer additives or surfactants. Oils from Lunaria annua L. is a member of the current major oilseed crops contain only a Crucifer family, native to south eastern limited range of fatty acids, thus there is Europe. It is grown in many temperate interest in other oil seed species to extend the countries for its translucent fruit, which are range of fatty acids available from renewable ornamental when dried, and is variously sources. known as Honesty, Money Plant, Moonwort or Calendula (Calendula officinalis L.), Satin Flower. It is a biennial and has a cold also known as pot marigold, is an annual or temperature vernalisation requirement (Pierik, short-lived perennial herb native to southern 1967). Its seed contains high levels of oil that Europe that produces orange to yellow is rich in long chain erucic and nervonic acids flowers. It is commonly grown as an (Princen and Rothfus, 1984), both suitable as ornamental throughout the world and is lubricants. Nervonic acid may also have cultivated in southern and eastern Europe. It is pharmaceutical uses. There are violet to grown for a drug, calendulae flos, obtained purple and white flowering types of Lunaria. from the flowers, particularly the petals Overseas trials have yielded 1-2 t/ha of (Bisset, 1994). There is also interest in Lunaria seed with an oil content of around 30- growing calendula seed in New Zealand. The 35%, of which 44% was erucic acid and 23% seed has an oil content of 5-20% (Meier zu nervonic acid (Cromack, 1998; Mastebroek Beerentrup and Robbelen, 1987; Angelini et and Marvin, 2000). al., 1997; Cromack and Smith, 1998), of As an initial step to evaluating these which up to 60% is calendic acid – (8-trans, two plants for seed oil production, crops were 10-trans, 12-cis)-octadecatrienoic acid) grown in Canterbury and the oils content and (Angelini et al., 1997; Cromack and Smith, composition analysed. 1998). This seed oil has similar properties to tung oil and, therefore, could be used as a Agronomy N.Z. 35, 2005 129 Initial studies on seed oil compositions Materials and Methods the sowing of the trial. To prevent any initial Site Details weed growth, the area was sprayed with a pre- Three field experiments, Calendula emergence herbicide (400 g/litre trifluralin at Cultivar 2002-3, Calendula Time of Harvest the rate of 1.5 litres/ha). The trial was set out 2003-4 and Lunaria 2002-4, were conducted as a randomised complete block with 6 on a Templeton silt loam overlying sand (New replicates. The crop was sown on 16 October Zealand Soil Bureau, 1968) at the Crop & 2003 with a 9 row Oyjord Drill with rows Food Research Farm at Lincoln in Canterbury spaced at 15 cm apart, at a seed rate of 24 (172o29’E 43o39’S). kg/ha. The plot length was 10 m with plots The average soil fertility status (Quick separated by a tractor wheel mark. Seeding Test values) of the top 300 mm of the 2002-3 depth was 1-2 cm, and the crop was covered trial area, taken in March 2002 was pH 5.9, Ca using light harrows attached to the drill. The 9, K 15, P 21, S 10 , and Mg 14. Soil samples crop was irrigated with overhead sprinklers at taken on the 2003-4 trial area in May 2003 2-3 week intervals from November to early averaged pH 5.9, Ca 7, K 10, P 17, S 4, and March. 100kg/ha N was applied as urea (46% Mg 13. Soil physical characteristics on an N) on 19 November, just prior to the start of adjacent area have been given by Martin et al. flowering. The urea was irrigated in with 25 (1992). mm water on the same day. The crop was hand weeded once prior to full flowering. Calendula cultivar trial 2002-2003 Six stages of seed head maturity (from Seeds of thirteen garden cultivars of completion of flowering until seed dried and Calendula officinalis were sourced from shedding) were identified for sampling companies in New Zealand, Australia and purposes to test oil composition. These stages United Kingdom. Two semi-commercial lines were: (NZ1 and NZ2) were obtained from New 1. Petals totally dried and fallen off and Zealand sources. All 15 lines were sown on 4 the seed-head formed; whole head still December 2002. A randomised block design green, and seed still soft. was used with 4 replications of single rows of 2. Change of sepal colour to light brown; each cultivar. There were 15 cm between the stamens folding in. rows and 15cm within the row, and 15 seed 3. Seeds hard to the touch and turning were sown per row. darker brown; sepals all drying out. The crop emerged between 15 and 30 4. Whole head light to dark brown; seeds December, and was top-dressed with urea (100 hard and all still closely held together. kg N/ha) on 30 January. The trial area was 5. Seed-head matured, seeds all dark irrigated (10-35 mm on 11 occasions) to keep brown and closed together. Sepals soil moistures above 20% gravimetric soil totally dry and falling off. moisture in the top 15 cm and weeded as 6. All seeds very dry, head starting to required to keep weed competition to a shed seed if plant lightly shaken. minimum. The plants were in bud on 15 February and in full flower by 1 March. The Twenty randomly selected heads were trial was hand harvested on 30 April. harvested from the middle five rows of each plot at each stage of maturity between mid- Calendula time of harvest trial 2003-4 February and mid-March. Due to severe weed Two Calendula cultivars (NZ1 and infestation in parts of the trial, only the high NZ2) were sown in the 2003-04 season at seeding plus nitrogen treatments within Lincoln. The area received 3 t/ha of 30% cultivars in two replicates were sampled from potassic super incorporated in the soil prior to the trial. Agronomy N.Z. 35, 2005 130 Initial studies on seed oil compositions Seed heads were dried at 30 oC in an alcohol-iso-octane phase. 250 µl samples of airflow drier before manually extracting the the iso-propyl alcohol-iso-octane containing seed. Seeds in ten-gram samples of seed from the FAMEs were removed to vials for each maturity stage were counted and retained immediate analysis by HP 6890 gas for oil analysis. chromatograph, using the following operating conditions: Lunaria Trial 2002-4 Column – 30 m, 0.32 mm i.d., 0.25 µm Six different cultivars of Lunaria film, HP Innowax fused silica capillary annua seed, sourced from companies in New column Zealand, Australia and United Kingdom, were Injection – splitless mode, automatic th sown at Lincoln on the 4 of December 2002 injector in a randomized block trial with six cultivars Carrier gas – hydrogen, constant flow, trial replicated 4 times. In each plot, 10 seeds 60 cm/sec per row were sown by hand at 15cm spacing Temperatures (oC) – inlet 230, detector between and within rows. 250, oven 150 initial to 190 at 4/minute, There was about 50% emergence over then to 230 at 10/minute. all the lines by 30 January, when 150 kg N/ha Peak detection was determined by was applied as urea. Some plants had to be flame ionisation detector. FAME levels are removed because they showed virus expressed as peak area percentages without infections, and other plants were damaged by correction for detector response. Methyl wind or sheep. This reduced plant populations palmitate, stearate, oleate, linoleate, α- and γ- by up to 50% in some plots. The plants were linolenates and calendate were identified by sprayed twice with Orthene before bud GCMS. Methyl myristate arachidate, behenate, development to prevent aphid attack. Buds erucate and lignocerate were identified by developed in late September and the plants comparison of retention times with a were all flowering by 20 October. Seed pods commercial AOCS#3 set of FAME standards formed by 24 November and the trial was (American Society of Oil Chemists, 1999). harvested on 15 January. The results were analysed with analysis of variance using the GenStat Oil yields and composition statistical package (GenStat Committee, 2003). All samples were dried at 30 oC and The time of harvest trial was analysed as a split ground. Moisture levels were determined on plot with cultivars as main plots and harvest at least 2 g ground samples on a Sartorius date as subplots.