Effect of Site Specific Nitrogen Management on Seed Nitrogen—A Driving Factor of Winter Oilseed Rape (Brassica napus L.) Yield

It has been assumed that the management of both soil and fertilizer N in winter oilseed rape (WOSR) is crucial for N accumulation in seeds (Nse) and yield. This hypothesis was evaluated based on field experiments conducted in 2008/09, 2009/10, 2010/11 seasons, each year at two sites, differing in soil fertility, including indigenous N (Ni) supply. The experimental factors consisted of two N fertilizers: N and NS, and four Nf rates: 0, 80, 120, 160 kg ha−1. Yield, as governed by site × Nf rate interaction, responded linearly to Nse at harvest. The maximum Nse (Nsemax), as evaluated by N input (Nin = Ni + Nf) to WOSR at spring regrowth, varied from 95 to 153 kg ha−1, and determined 80% of yield variability. The basic reason of site diversity in Nsemax was Ni efficiency, ranging from 46% to 70%, respectively. The second cause of Nse variability was a shortage of N supply from + 9.5 soil to −8.8 kg ha−1 to the growing seeds during the seed filling period (SFP). This N pool supports the N concentration in seeds, resulting in both seed density and a seed weight increase, finally leading to a yield increase.

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Dynamics of Growth and Nitrogen Capture in Winter Oilseed Rape Hybrid and Line Cultivars under Contrasting N Supply

Agronomy ◽

10.3390/agronomy10081183 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1183 ◽

Cited By ~ 1

Author(s):

Yangyang Zhang ◽

Piaopiao Lu ◽

Tao Ren ◽

Jianwei Lu ◽

Li Wang

Keyword(s):

Oilseed Rape ◽

Seed Yield ◽

Field Experiments ◽

N Uptake ◽

Genotypic Variation ◽

Utilization Efficiency ◽

Winter Oilseed Rape ◽

N Accumulation ◽

N Supply ◽

Parental Lines

Cultivation of winter oilseed rape hybrids has been introduced as a promising solution to improve the nitrogen use efficiency (NUE) and to reduce the large N balance surpluses in this crop. To achieve a better understanding of the underlying physiological mechanisms, field experiments were conducted over two years to investigate the dynamics of growth and N capture in an oilseed rape hybrid and its parental lines under both low (0 kg ha−1) and high (180 kg ha−1) N supply. The results showed that the dynamic trajectories of crop growth and N capture could be accurately characterized by logistic equation using growing degree days as the independent variable. At both N rates, the oilseed rape hybrid outperformed the parental lines in seed yield and aboveground biomass accumulation, which was more closely associated with the longer duration (td) of the rapid growth period (RGP), than with the higher maximum growth rate (vm). N uptake was the main factor driving genotypic variation in seed yield, with an increasing importance of N utilization efficiency at high N supply. The hybrid had significantly higher N uptake than the parental lines at both low and high N supply, because of larger vm for N accumulation during the RGP, which may present a scope for genetically improving NUE in oilseed rape. High N application enhanced crop biomass production and N accumulation, as a result of prolonged td and larger vm during the RGP. The initiation of RGP for N accumulation occurred after overwinter period, which could not be accelerated by high N supply, suggesting rational distribution of N fertilizer with reduced basal dose. However, larger amounts in spring would be beneficial for a better synchronization to crop N demand with lower environmental risks.

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Soil Extracellular Enzyme Activities and Uptake of N by Oilseed Rape Depending on Fertilization and Seaweed Biostimulant Application

Agronomy ◽

10.3390/agronomy9090480 ◽

2019 ◽

Vol 9 (9) ◽

pp. 480 ◽

Cited By ~ 6

Author(s):

Anetta Siwik-Ziomek ◽

Małgorzata Szczepanek

Keyword(s):

Oilseed Rape ◽

Field Experiments ◽

Extracellular Enzyme ◽

Winter Oilseed Rape ◽

N Accumulation ◽

Development Stages ◽

Npk Fertilizer ◽

Fertilizer Rates ◽

Insufficient Knowledge ◽

Npk Fertilization

The present study has aimed at enhancing the insufficient knowledge of functional soil enzymes properties influenced by inorganic fertilization and biostimulant application to increase the uptake of nitrogen affecting the winter oilseed rape yield. Field experiments were conducted in Poland (53° N, 18° E) in Alfisol (USDA). In this experiment, the NPK rates applied were as follows: high 180 N, 70 P and 160 K 132 N (kg ha−1) or low 144 N, 35 P and 66 K (kg ha−1); fertilization with elemental S 36 or 0 (kg ha−1); and the seaweed biostimulant Kelpak was applied or there was no such treatment. Due to low NPK fertilization rates, the activity of dehydrogenases, peroxidases, and catalase increased in subsistent generative development stages from flowering to ripening. At the ripening stage, the activity of these enzymes, as well as nitroreductase activity, were inhibited by high NPK fertilizer rates. The seaweed biostimulant application and S fertilization increased N accumulation in plants of oilseed rape in generative development, by 16% and 13%, respectively, as compared with the lack of these treatments. The application of S increased the uptake of nitrogen in shoots and in whole oilseed rape plants only after application of higher rates of NPK.

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Dry matter and nitrogen partitioning and translocation in winter oilseed rape (Brassica napus L.) grown under rainfed Mediterranean conditions

Crop and Pasture Science ◽

10.1071/cp12401 ◽

2013 ◽

Vol 64 (2) ◽

pp. 115 ◽

Cited By ~ 17

Author(s):

A. N. Papantoniou ◽

J. T. Tsialtas ◽

D. K. Papakosta

Keyword(s):

Brassica Napus ◽

Oilseed Rape ◽

Dry Matter ◽

Winter Oilseed Rape ◽

Brassica Napus L ◽

N Accumulation ◽

Growing Seasons ◽

Pod Development ◽

Net Assimilation ◽

Mediterranean Conditions

For crops grown in Mediterranean environments, translocation of pre-anthesis assimilates to the fruit is of great importance, because hot and dry conditions during fruit ripening diminish net assimilation rate and nitrogen (N) uptake. This field study was conducted to assess the pattern of dry matter and N accumulation and the role of assimilate translocation in pod development of oilseed rape plants in a Mediterranean environment. Four cultivars of winter oilseed rape (Brassica napus L.), i.e. three hybrids (Royal, Exact, Excalibur) and an inbred line (Fortis), were grown for two growing seasons (2005–06 and 2006–07) in northern Greece. On average, 581, 1247, 1609, and 2749 growing degree-days (GDD) were required for six leaves, stem elongation, 50% anthesis in main stem, and physiological maturity in the first year, and 539, 1085, 1601, and 2728 GDD in the second year. The R2 of the modified Richards function indicated that aboveground biomass and N accumulation were described with high approximation efficacy. The across-cultivars genotype mean maximum predicted total aboveground dry matter and N content were 1368.8 and 21.4 g m–2 in 2006 and 1655.1 and 25.4 g m–2 in 2007. In 2007, dry matter and N translocation from vegetative tissues to pods were 464.4 and 21.0 g m–2, and significantly higher than the corresponding values recorded in 2006 (264.4 and 17.0 g m–2). These differences were due to greater amounts of dry matter and N accumulating at anthesis and the greater sink capacity of plants (pod number) in 2007. The fact that pod development occurred in a period when N accumulation by oilseed rape plants had stopped led to high values of contribution of pre-anthesis N accumulation to pod N content in both years (92.8% in 2006 and 96.6% in 2007). Results indicated that hot and dry weather post anthesis reduced dramatically the net assimilation rates; thus, translocation of pre-anthesis assimilates was crucial for pod development. The results demonstrate that variation in weather conditions between growing seasons is one of the main causes of seasonal variation in oilseed rape productivity under Mediterranean conditions.

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Segregation of Triazine-Resistant Chloroplasts after Introduction into Winter Type Oilseed Rape (Brassica napus L.) by Protoplast Fusion

Zeitschrift für Naturforschung C ◽

10.1515/znc-1990-0530 ◽

1990 ◽

Vol 45 (5) ◽

pp. 478-481

Author(s):

R. Hain ◽

J. E. Thomzik

Keyword(s):

Brassica Napus ◽

Plant Growth ◽

Protoplast Fusion ◽

Oilseed Rape ◽

Field Experiments ◽

Rflp Analysis ◽

Winter Oilseed Rape ◽

Brassica Napus L ◽

X Irradiation ◽

Spring Type

Abstract Triazine-resistant chloroplasts of the Canadian spring oilseed rape variety OAC Triton were transferred into four German winter oilseed rape lines and two cultivars of double-low quality by means of protoplast fusion. X-irradiation has been used to reduce the amount of nuclear D N A of the spring type cultivar and to promote cybrid formation. RFLP-analysis showed that some regenerants and their progeny carried both types of chloroplasts. In some instances regenerants and progeny containing mixtures of both chloroplasts not kept under selective conditions lost their triazine-resistant chloroplasts completely during further plant growth. Preliminary results of greenhouse and field experiments indicate that volunteer plants can be eliminated by application of 150-300 g/ha metribuzin (SencorR, Bayer AG) in a stand of triazine-resistant oilseed rape of double-low quality.

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Evaluation of Nitrogen Fertilization Systems Based on the in-Season Variability in the Nitrogenous Growth Factor and Soil Fertility Factors—A Case of Winter Oilseed Rape (Brassica napus L.)

Agronomy ◽

10.3390/agronomy10111701 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1701 ◽

Cited By ~ 1

Author(s):

Witold Grzebisz ◽

Remigiusz Łukowiak ◽

Karol Kotnis

Keyword(s):

Oilseed Rape ◽

Nitrogen Fertilization ◽

Field Experiments ◽

Positive Impact ◽

Maximum Yield ◽

High Yield ◽

Available Phosphorus ◽

Winter Oilseed Rape ◽

Brassica Napus L ◽

N Rates

Application of nitrogen (N) in contrastive chemical form changes availability of soil nutrients, affecting crop response. This hypothesis was evaluated based on field experiments conducted in 2015/16 and 2016/2017. The experiment consisted of three nitrogen fertilization systems: mineral-ammonium nitrate (AN) (M-NFS), organic-digestate (O-NFS), 2/3 digestate + 1/3 AN (OM-NFS), and N rates: 0, 80, 120, 160; 240 kg ha−1. The content of nitrogen nitrate (N-NO3) and available phosphorus (P), potassium (K), magnesium (Mg) and calcium (Ca) were determined at rosette, onset of flowering, and maturity of winter oilseed rape (WOSR) growth from three soil layers: 0.0–0.3, 0.3–0.6, 0.6–0.9 m. The optimum N rates were: 139, 171 and 210 kg ha−1 for the maximum yield of 3.616, 3.887, 4.195 t ha−1, for M-NFS, O-NFS, OM-NFS. The N-NO3 content at rosette of 150 kg ha−1 and its decrease to 48 kg ha−1 at the onset of flowering was the prerequisite of high yield. The key factor limiting yield in the M-NFS was the shortage of Ca, Mg, O-NFS—shortage of N-NO3. Plants in the OM-NFS were well-balanced due to a positive impact of the subsoil Mg and Ca on the N-NO3 content and productivity. The rosette stage was revealed as the cardinal for the correction of WOSR N nutritional status.

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Sources of Nutrients for High-Yielding Winter Oilseed Rape (Brassica napus L.) during Post-Flowering Growth

Agronomy ◽

10.3390/agronomy10050626 ◽

2020 ◽

Vol 10 (5) ◽

pp. 626 ◽

Cited By ~ 3

Author(s):

Witold Grzebisz ◽

Witold Szczepaniak ◽

Stanisław Grześ

Keyword(s):

Brassica Napus ◽

Oilseed Rape ◽

Field Experiments ◽

Nutrient Management ◽

Seed Density ◽

Winter Oilseed Rape ◽

K Uptake ◽

Brassica Napus L ◽

Net Uptake ◽

Excessive Accumulation

Nutrient management by winter oilseed rape (WOSR) during the seed filling period (SFP) is crucial for seed density (SD), which subsequently determines seed yield (Y). This hypothesis was evaluated based on data from field experiments (2008-2010), with six treatments with sequentially added nutrients (0, NP, NPK, NPKMgS1(1/3 total MgS rate—spring applied), NPKMgS2 (total MgS rate autumn applied); NPKMgS3 (2/3-autumn, 1/3-spring). Nutrients accumulated in seeds were revealed as the most reliable WOSR trait, determining SD and Y. Yield was defined by the amounts of K and Mg in seeds. The amount nutrient remobilized from vegetative WOSR tissues was sufficient to cover the crop requirements during SFP for N, P, and Zn, but not for Ca, K, Mn, and Cu. The post-flowering K uptake resulted in PD, and SD increase, which subsequently resulted in a concomitant net uptake of Ca and Mg. The excessive accumulation of Ca, as well as Cu, and Mn in seeds due to a shortage of Mg, subsequently resulted in both SD and Y depression. The efficient exploitation of WOSR yielding potential as defined by SD, is possible, provided during the SFP reveals a net K and Mg uptake.

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