European Journal of Agronomy 12 2000 127–141 www.elsevier.comlocateeja
Influence of sulfur on apparent N-use efficiency, yield and quality of oilseed rape Brassica napus L.
grown on a calcareous soil
J. Fismes a, P.C. Vong a,, A. Guckert a, E. Frossard b
a Laboratoire Agronomie et Environnement ENSAIA-INRA, 54505 Vandoeuvre le`s Nancy cedex, France b Ecole Polytechnique Fe´de´rale de Zurich, Eschikon 33, CH-8315 Lindau, Switzerland
Accepted 4 October 1999
Abstract
In the Lorraine region, major soils used for winter oilseed rape are calcareous. Across two pot and two field experiments, we studied the influence of sulfur applied at different levels on apparent N-use efficiency ANU , yield,
glucosinolate GLS and oil content of seeds. The soil received a constant dose of 200 kg N ha−1 as ammonium nitrate, urea or cow slurry and three levels of S: 0, 30 and 75 kg ha−1 as ammonium thiosulfate ATS, MgSO4 or
ATS plus MgSO 4
. Apparently, oilseed rape is a N-inefficient crop as revealed by low ANU values which varied within 36 and 53
from field experiment versus 25 and 61 under controlled conditions. In both cases, S additions improved
N-use efficiency only at the highest dose of 75 kg S ha−1, which is not attained by ATS with 35 kg S ha−1 10 vv.
S fertilization increased the GLS contents that were found to be negatively correlated with plant NS uptake ratios observed at maturity. The most important increase in GLS content by 52
was noted with cow slurry in the pot experiment. But, as a whole, the GLS levels remain below the European norm of 18 mmol g seed−1. Moreover, the
oil content DM of seeds decreased but the total production increased when the soil was fertilized with N and
with or without S. The results showed that N and S nutrition during the growth were tightly linked. Their interactions, as reflected by plant uptake, are synergistic at optimum rates and antagonistic at excessive levels of one of the both.
Collectively, the results indicate that S fertilization is required to improve N-use efficiency and thereby maintaining a sufficient oil level and fatty acid quality. © 2000 Elsevier Science B.V. All rights reserved.
Keywords: Ammonium thiosulfate; Apparent N-use efficiency; Glucosinolate and oil content; N and S interactions; N and S nutrition; Oilseed rape
1. Introduction Ceccoti, 1996. Consequently, the poor efficiency
of N caused by insufficient S needed to convert N into biomass production may increase N losses
Nitrogen and sulfur are both involved in plant from cultivated soils Schnug et al., 1993.
protein synthesis. The shortage in S supply for Oilseed rape Brassica napus L. is an important
crops decreases the N-use efficiency of fertilizers oilseed crop in the Northern agricultural region of
France. In the region of Lorraine, major soils used
Corresponding author. Tel.: +33-383-59-58-98;
for this crop are calcareous, rich in organic-N and
fax: +33-383-59-57-99.
organic-S, but a deficiency in available S at the
E-mail address: phuy-chhoy.vongensaia.inpl-nancy.fr P.C. Vong
beginning of the growing season is often detected.
1161-030100 - see front matter © 2000 Elsevier Science B.V. All rights reserved. PII: S 1 1 6 1 -0 3 0 1 9 9 0 0 05 2 - 0
128 J. Fismes et al. European Journal of Agronomy 12 2000 127–141
This could be due to either important losses of in calcareous soils when S supply was above
30 kg ha−1, and an application of 60 kg S ha−1 sulfates by leaching during the winter, which can
reach 80 kg ha−1 Suhardi, 1992, or slow min- increased the GLS content by 20
. However, with the general widespread use of double O cultivars,
eralization hampered by both low spring temper- ature and alkaline nature of these soils Merrien,
reasonable levels of GLS can be achieved owing to the ability of these cultivars to store Zhao
1988. Nutritionally, oilseed rape and Brassica species
et al., 1993a and to regulate Fismes et al., 1999 the excess of S in pod walls. Based on these
in general require S during their growth Zhao et al., 1993a, for the synthesis of both protein
observations, sufficient S supply to maintain the optimum yield is required. For this purpose, ATS
and naturally occurring glucosinolates. Oilseed rape is thus particularly sensitive to S deficiency,
is gaining in use, because besides the inhibitory actions on N, it contains high S concentration
and in the last 10 years, significant yield responses to S application jointly with N have been achieved
Goos, 1985. In field studies, apart from maize Graziano
and Parente,
1996, bromegrass
Janzen and Bettany, 1984; Merrien, 1988; Zhao et al., 1993b; Withers and O’Donnel, 1994;
Lemond et al., 1995 and recently tall fescue Sweeney and Moyer, 1997, its extension to other
MacGrath and Zhao, 1996. In general, higher plants assimilate N and S in
crops such as rapeseed is scantily reported in the literature. On the other hand, there is a substantial
amounts proportional to that incorporated into amino acids and proteins, which suggests that N
body of information on plant N nutrition and the data related to both N and S are still very poor,
and S requirements are closely interrelated Rendig et al., 1976; Friedrich and Schrader, 1978.
at least for rapeseed. Accounting for the above observations, this work aimed to examine how
Increasing N fertilizer rates aggravate S deficiency of oilseed rape and reduce seed yield when avail-
increasing levels of S fertilization in such a calcare- ous soil could affect the efficiency of N utilization
able S is limiting Janzen and Bettany, 1984. A NS ratio value 16 in plant tissues indicates that
and thereby the yield and the quality of seed, in particular the GLS and oil content. It also gives
S is insufficient for protein formation in maize Cassel et al., 1996 and tall fescue Sweeney and
further information about the links which exist between N and S nutrition at the main stages of
Moyer, 1997 and the excess of unassimilated NO−
3 –N, amides or free amino acids accumulates
plant growth. Sexton et al., 1997. Conversely, N addition
increases seed yield in S-sufficient conditions, and an optimum oil quality and maximum yield
2. Materials and methods
