Index | Search | Home | Table of Contents
Jasso de Rodriguez, D., B.S. Phillips, R. Rodriguez-García, and J.L. Angulo-Sánchez. 2002. Grain yield and fatty acid composition of sunflower seed for cultivars developed under dry land conditions. p. 139142. In: J. Janick and A. Whipkey (eds.), Trends in new crops and new uses. ASHS Press, Alexandria, VA.
Diana Jasso de Rodriguez, Bliss S. Phillips, Raúl Rodriguez-García, and José Luis Angulo-Sánchez
Mexico imports about 85% of oilseed for edible oil extraction, sunflower is an option for local oilseed production, particularly in dry land areas due to good root system development. Sunflower oil quality is high due to its fatty acid composition which is dependent on climatic conditions.
The content of sunflower oil has about 110 g kg-1 of saturated fatty acids (16:0 and 18:0). In typical cultivars, the major fatty acids are 18:1 and 18:2, depending on the duration of high temperatures during the growth and development stages of the seed. Fatty acid composition of the oil determines its use as an industrial or edible oil (Osorio et al. 1995). Although the oil of cultivar sunflower seed is considered of good quality for edible purposes, the development of cultivars with high oleic acid content is, at the present, an important improvement (Martínez et al. 1993). It is necessary to know the accumulation of linoleic acid of oil in order to establish the relationships among oil content, quality, and temperature (Goyne et al. 1979). Studies have been carried out on sowing dates in sunflower (Helianthus annuus L., Asteraceae) from 1969 to 1971 (Johnson and Jellum 1972), in order to evaluate the optimal sowing date for seed yield, percentage of oil, composition of fatty acids, and other plant traits. Better seed yields, and oil, were obtained when sunflower was sowed from the middle of March until April. Other characteristics were not significantly affected, but those in the sowing made from June to July. It has been demonstrated that the sowing date may have a bigger effect on yield, and quality of sunflower seed.
In studies performed in the North of Australia by Keefer et al. (1976) and Garside (1984). May sowing of the late maturing Hysun 30 was the best combination, yielding 2.3 tonnes (t)/ha but quality and oil content were higher in the April sowing, (47% and 57% respectively). The April and July dates had acceptable yields, 1.8 and 2.0 t/ha respectively; and oil content (45% to 47%). In contrast Miurhead (1974) obtained similar yields in sowing from the July 22 to Dec. 31.
In the arid and semi-arid areas of Mexico precipitation is scarce, and producers require adapted sunflower cultivars. The objective of this study was to evaluate the grain yield and fatty acid oil composition of sunflower seed in 5 cultivars grown under dry land conditions in Northern Mexico.
The sowing trial was carried out at the Experimental Field of the University Antonio Narro on June 21 2000, under a random block design with four replications. The distance among furrows was 0.8 m, and among plants 0.25 m for a density of 50,000 plants/ha, plot size was 48 m2. Cultivars evaluated were Gordis, San-3C, Sane 1278, and Sane 23578 (developed at the University Antonia Narro) and Rib 77 (control).
Irrigation was applied only after sowing to promote emergence. The evaluated parameters were: number of leaves, plant height, head diameter (in three dates of development of the cultivation, taking 6 plants at random per parcel); dry weight, grain yield (in harvest, sampling the plants in 3 m2); oil content, fatty acid composition, and protein content.
In each of the sampling dates, plants were taken to the laboratory and oven dried at 65°C, for dry weight determination. Heads were severed from the plants and then threshed, grain humidity was determined, and then grain yield calculated. Protein content was determined in the Kjeldahl digestor and oil content and fatty acid composition was determined through liquid chromatography in the New Crops Research laboratory, NCAUR/ARS/USDA, Peoria Illinois.
During the experiment, maximum temperatures ranged from 30.0° to 32.0°C, and minimum temperatures from 7.0° to 14.8°C, with average temperatures from 20.3° to 22.8°C (Table 1). There was precipitation in July and August, when the crop was in the vegetative and flowering stages; total precipitation was 164 mm during the crop cycle (Table 1).
Table 1. Temperature and rainfall recorded from June 21 to Sept. 28, 2000.
During the flowering stage San-3C had the highest number of leaves (34); Sane 1278 and Sane 23578 had 27 leaves each (Fig. 1). San-3C was tallest (1.44 m) by the end of flowering (Fig. 2). San-3C had the largest head diameter (15.7 cm), followed by Gordis and Sane 1278 (Fig. 3). At grain filling, Rib 77 and Sane 23578 tended to reduce head diameter. At harvest, the dry matter yield was 9.5 t/ha for Rib 77 (Fig. 4), followed by San-3C (8.7 t/ha), Gordis (6.2 t/ha), Sane 23578 (5.51 t/ha), and Sane 1278 (5.12 t/ha).
|Fig. 1. Number of leaves at three stages of sunflower development.||Fig. 2. Plant height at three stages of sunflower development.|
|Fig. 3. Head diameter at three stages of sunflower development.
San-3C had the highest grain yield (2.3 t/ha) (Fig. 5). Thompson and Hennan (1994) reported yields of 4.3 t/ha (for cultivars sown in late October) and 2.9 t/ha (for cultivars sown in late January), in irrigated experiments. Yields of 2.3 t/ha, without irrigation suggests sunflowers as an alternative crop for this region.
|Fig. 4. Dry weight production at harvest for sunflower cultivars.
||Fig. 5. Grain yield of sunflower cultivars.|
Oil content analyzed at grain filling and harvest (Fig. 6) indicated a slight decrease from grain filling to harvest (25% to 40% depending on cultivar). The low oil content may be due to the short grain filling stage caused by the lack of irrigation and high temperatures during this period. Thompson and Hennan (1994) report oil percentages of 43.8%, for cultivars sown in late January if they are well watered during their development.
The composition of sunflower seed fatty acids from grain filling to harvest differs depending on fatty acids and cultivar (Table 2). Linoleic acid was less than commercial oil but higher than the 62% required for margarine (McLeod et al. 1990; Thompson and Hennan 1994). Protein content was highest at harvest (Fig. 7) but differed slightly among sampling dates.
|Fig. 6. Oil content of sunflower cultivars evaluated at grain fill
||Fig. 7. Protein content of sunflower cultivars evaluated at grain fill and harvest.|
Table 2. Fatty acid composition of sunflower seed at two sampling stages.
|Sampling stage, varieties,
and check control
|Fatty acids (%)|
|16:0 Palmitic||18:0 Stearic||18:1 Oleic||18:2 Linoleic|
|Sunflower oil commercial||6.0||4.6||17.8||69.2|
|High oleic sunflower||3.6||4.8||78.9||10.2|
The grain yield of San-3C (2.3 t/ha) is outstanding in view of the drought conditions. Cultivars with yields of 1.4 to 1.5 t/ha represent an alternative for farmers in the Arid and Semi-arid Areas of Mexico. The fatty acid composition of cultivars developed at the University Antonio Narro, is similar to that of commercial sunflower oil and linoleic acid levels (>62%) exceed requirements for the margarine industry. These results indicated that sunflower cultivars developed at the University Antonio Narro have commercial quality.