Agronomic Characteristics of Confectionery Sunflower

 Grown in Florida, USA

 Victor E. Green, Jr.
 Agronomy Department, IFAS
 University of Florida
 Gainesville, FL 32611, USA


 Testing of confectionery (non-oilseed) sunflower cultivars
between 1978 and 1980 in north-central Florida on drought
sandy soils permitted the agronomic characterization of 22
cultivars. These striped, large-seeded varieties are used for
confection either in the shell or shelled, salted or unsalted or
as bird feed, usually in the shell. Testing was performed at two
locations and plantings were made in February, March, April,
and Augsut. The data show that sunflower could be added to
the crops used in the multiple or relay systems of crop culture
common in this area. The chief obstacle to successful
sunflower culture in this area is the Alternaria leaf and stem
black spot disease caused by the fungus Alternaria helianthi


(Hansf.) Tubaki and Nishihara. The first epiphytotic of this
disease to occur in the USA was in these and adjacent plots
near Gainesville, Alachua County, Florida. Meteorological
data including monthly rainfall, growing degree days (GDD)
calculated from monthly maximum and minimum tempera-
tures, and total radiation and photosynthetically active radia-
tion are shown tabularly for 1978-1980.
Keywords: Helianthus annuus L., sun-nuts, birdseed, non-
oilseed sunflower, striped sunflower seed, linoleic acid, fatty
acids, sunflower oil, Alternaria helianthi leaf and stem black
spot disease.


 Seed of the confectionery sunflower, Helianthus annuus L.,
cultivars are large, enclosed loosely in large striped achenes and
are usually used either as feed for tame or wild birds or are used as
a snack for humans. They are sold shelled or unshelled, and
salted or unsalted. Due to the deep rooting characteristics of
sunflower and the ability of the species to withstand frost as seed-
lings or as maturing plants, confectionery cultivars offer a source
of good food supplement in most areas of the world.
 Green and Robertson (1983) pointed out that the 'sun-nuts' of
this type sunflower had almost identical fatty acid composition as
oilseed hybrids. Although the total oil content of the achenes
which contain the sun-nuts is smaller in the confectionery hybrids
than in the oilseed hybrids, since no genetic selection has been
used for high or low oil content in the confectionery hybrids, it
would seem preferable to grow the large-seeded, striped hybrids
in which the nuts are loosely bound in the achenes, so that the
nuts could easily be removed from the hulls by the teeth or by
impact hullers than have a lower energy requirement. The
resulting nuts have high oil and high protein contents, and offer
a good source of nutritive calories, especially for peoples in the
developing countries of the world. The hybrids can be grown
anytime during the year where water is available, the land is not
subject to flooding, and the growing period is free from extremes
in weather. Birds can be a problem when growing this crop.
Sunflower seeds are high in linoleic acid, an essential fatty acid in
human nutrition. There is probably not a more palatable linoleic
acid source than roasted and salted sun-nuts.
 The objective of this research was to locate and test confec-
tionery sunflower hybrids in north-central Florida over a 3-year
period to determine whether it would be agronomically feasible
to recommend the crop commercially

MATERIALS AND METHODS
 Eleven tests including 22 cultivars, two of which were open-
pollinated varieites, were conducted from 1978 to 1980. Four
tests in 1978 were planted in March, April, and two in August. In
1979, there were four tests planted in February (two), April, and


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August. In 1980, two tests were seeded in March, an one in mid-
August. The exact dates and cultivars are seen in Table 1. The
tests of 2 April 1979, and 6 March and 14 August 1980, were
planted at the Campus Agronomy Farm. The remaining tests
were planted eight miles west at the Green Acres Farm.
 Rows always ran north and south to facilitate hand harvest and
were always about 91 cm. (36 inches) apart. Prior soil treatments
were plowing and disking. Each time Treflan herbicide from
Elanco Corporation and Furadan insecticide /nematicide from
FMC Corporation were applied into the soil at the recommended
rates a few weeks before the seed were dropped. Fertilizer
treatments included pre-plant application of 672 kg. of 4-8-16 in-
cluding micronutrients necessary for plant production in north-
central Florida. Side dressings of ammonium nitrate were applied
before the plants reached the toolbar height, to facilitate
coverage of the incorporated material. Amounts varied according
to the amounts of rainfall received before lay-by time, ranging
from 112 to 336 kg per hectare. Seed were hand planted in suffi-
cient quantity so that the plots could be hand thinned to a stand
of about 55,000-62,500 plants per hectare. Cultivation was
seldom necessary due to pre-plant herbicides and the covering of
side-dressed nitrogen fertilizer. All tests were planted in ran-
domized complete blocks with either four or six replications.
 During the growing season the following data were collected:
planting and emergence dates, heading and physiological maturi-
ty dates, plant heights, stand counts, bird and insect damage,
disease index, and lodging. At maturity, seed heads were
counted in the center row of 3-row plots and in the two center
rows of 4-row plots. The heads were measured as to their
diameter. The heads were cut, bagged, dried to constant weight,
threshed, and the seed were transferred to the laboratory where
the following procedures were accomplished: screening over hard-
ware cloth to remove pieces of the heads, cleaning in a Bates
Aspirator to remove empty achenes and dust, and selecting
samples for moisture determination and weights per unit
volume. Finally, 200 seed from each sample were weighed. Clean
seed per plot weights were extrapolated to hectare yields.


 PROCEEDINGS of the CARIBBEAN FOOD CROPS SOCIETY-VOL. XX