2.1. Field trial
Afield trial was conducted in 2010 at the Interdepartmental
Centre for Agro-Environmental Research“E. Avanzi”(CIRAA) of the
University of Pisa. CIRAA is located on the northern coast of Tuscany, 8 km SW of Pisa and 1 km E of the Tyrrhenian Sea on the
southern side of the Arno river (lat. 42
41
0
, long. 10
23
0
). Climatic
conditions are typical of Mediterranean areas. Mean monthly air
temperature varies from 11
C in February to 30
C in August.
Rainfall is concentrated in autumn (OctobereNovember) and
spring (MarcheApril).
Thefield experiment was established on a clay loam soil, characterized by 27.7% clay, 32.6% sand, 39.7% silt and 2.9% organic
matter. The proximity to the Arno River determines a high water
table in the site, which reduces crop water stress during summer.
Two high-oleic sunflower hybrids (PR64 H31 and PR65 H41,
hereafter named H31 and H41) were sown on the 23rd of April,
2010. The experiment was laid out as an openfield trial, with asinglefield divided in two main plots corresponding to each hybrid.
Crop management was carried out following the common agronomic practices adopted in the region[31].
At physiological maturity, when average seed moisture was
lower than 20%, four sampling areas of 1.2 m
2
per hybrid were
harvested. In the laboratory, fresh weight of total above ground
biomass (AGB) and grain was determined. Dry weight was determined after drying subsamples of the different plant organs in an
oven with forced ventilation at 80
C for 72 h.
Seed samples from a conventional sunflower hybrid (Coralia)
grown at CIRAA were collected at crop maturity and used in the
seeds processing phase in order to compare the performance of
high-oleic varieties with a conventional hybrid