82 research outputs found
Yield and oil variability in modern varieties of high-erucic winter oilseed rape (Brassica napus L. var. oleifera) and Ethiopian mustard (Brassica carinata A. Braun) under reduced agricultural inputs
No full textIncreasing interest in vegetable oils for use in green chemistry has stimulated research into high-erucic Brassicaceae species such as winter oilseed rape (Brassica napus L. var. oleifera) and Ethiopian mustard (Brassica carinata A. Braun). The objective of this study was to determine the yield response of recently released cultivars of these species under high and low production inputs. The varieties Maplus and Hearty of B. napus, and BRK1 of B. carinata were cultivated with autumn sowing in a large-scale field trial at the experimental farm of the University of Padova in Legnaro (NE Italy, 45 degrees 21'N). The genotypes were compared under high and low input management systems: high input was characterised by conventional soil tillage, chemical weed control, and high N-P-K fertilization, and low input by minimum tillage, mechanical weed control, and limited N-P-K fertilization.
Oilseed rape varieties had greater seed yield than BRK1, and interactions with input level and cultivation year were significant. Maplus yielded most at high input (3.78 vs. 3.31 t ha(-1) DM at low; average of two years), whereas Hearty showed no significant differences between inputs (3.49 t ha(-1); average of years and inputs), indicating its better adaptability to extensive agricultural management. Yield performance of BRK1 B. carinata was very stable at varying agricultural managements, but not very high (2.73 t ha(-1) on average) - a fact that may limit its competitiveness with oilseed rape in autumn sowing, especially at higher latitudes. B. carinata was also more variable across the years than oilseed rape in terms of seed yield, oil content, and percentage of erucic acid. This was mainly due to the particular climatic conditions of the second year of the experiment (mild winter: hot, dry spring) which led to considerable winter elongation and pre-flowering, and later to incomplete seed filling. In these conditions, BRK1 had both lower oil seed content (36.7% vs. 47.1%) and erucic acid (41.3% vs. 49.1%) than oilseed rapes.
In general, with few exceptions, the reduction in inputs did not affect either seed oil content or the amount of erucic acid, regardless of variety and year, but seed crude proteins were reduced mainly because of N shortage. (C) 2009 Elsevier B.V. All rights reserved
Is the root system the key to higher nitrogen uptake in rapeseed? The case of a composite hybrid line.
No full textThe recently commercialised rapeseed CHL (composite hybrid lines) are reported to give an average increase of about 15% in grain yield compared with 'old' varieties in normal growing conditions in France. In Italy, this observation has not be confirmed, since CHL Synergy and a good-yielding variety Ceres generally have similar yields (average of 12 field trials). However, several differences in morphological and physiological characters have been identified in the two genotypes, especially at root level.
Both shoot biomass and the amount of shoot nitrogen in Synergy were slightly higher compared with Ceres for most of the growing season, until the end of winter. As regards the root system, Synergy shows evident hybrid vigour, having faster and, especially in early stages, greater weight and total length than Ceres, together with higher specific root length. These traits are a prerequisite for the uptake of greater amounts of nitrogen, which may eventually be leached.
Although an increase in plant density led to higher root length density in the first soil layer (0-30 cm) for both varieties, nitrate leaching of Synergy exceeded that of Ceres at the high plant density, thus indicating that this hybrid is more sensitive to competition for nitrogen uptake. The increase in nitrate uptake rate per unit root length (Vmax) found for the hybrid compared with the 'old' variety was accompanied by an unfavourable increment of affinity (1/Km), which may be responsible of a loss of efficiency at high plant density. The morphological and physiological modifications of the hybrid seem to be more useful for reducing nitrogen leaching rather than for increasing grain yield
Performance of Crambe abyssinica as new crop for non-food uses in North-East Italy
No full textHigh erucic acid oils are a potential source of raw material for some oleochemical transformations as well as for direct use in the production of erucamide – a slip agent for plastic films (Walker, 2004). High erucic acid rapeseed (HEAR) is the common Wgreen” source of erucic acid and it is mainly cultivated in central Europe. Crambe abyssinica Hochst ex R.E. Fries is another interesting crop for such industrial uses, capable of yielding even higher amounts of erucic acid than HEAR (Bondioli et al., 1998; Temple-Heald, 2004). Crambe has been studied for many years (Meijer et al., 1999), but its spread is still limited in our environment, because of its poor adaptability to the European continental climate (Fontana et al., 1998). This crop, native to the Mediterranean regions of North Africa, has positive agronomic traits, such as tolerance to drought and good adaptability to poor sandy soil. Conversely, it does not tolerate cold or waterlogging, so that solely spring sowing must be adopted in central and northern Europe. Aiming at testing the possibility of introducing Crambe abyssinica in the typical crop rotations of North-East Italy and establishing its yield potential, a two-year field trial was set up at the experimental farm of the University of Padova
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