Critical phosphorus concentrations in oilseed rape (Brassica napus) and Indian mustard (Brassica juncea) as affected by nitrogen and plant age

1991 ◽  
Vol 31 (1) ◽  
pp. 107 ◽  
Author(s):  
A Pinkerton
Keyword(s):  
Oilseed Rape ◽  
Stem Elongation ◽  
Indian Mustard ◽  
Critical Values ◽  
Plant Age ◽  
Sand Culture ◽  
Mustard Seed ◽  
P Deficiency ◽  
N Supply ◽  
Oil Concentration

Oilseed rape and Indian mustard were grown in sand culture experiments in a glasshouse to derive values for a tissue test for the diagnosis of phosphorus (P) deficiency. Seven rates of P, combined factorially with 3 rates of nitrogen (N), were used to determine critical P concentrations. Suitable tissues to sample for a diagnostic test were the whole shoot of both species at any stage, or the youngest fully expanded leaf of rape and leaves 4-6 of mustard at the rosette stage. Critical P concentrations depended on both plant age and N supply. The critical values reported here for rape agreed closely with critical values found previously in tissues of field-grown crops of similar phenological age. Critical P levels in whole rape shoots adequately supplied with N decreased from 0.29% at the early rosette stage to 0.21% at the late rosette or yellow bud stage, while critical values in mustard fell from 0.25% at the early rosette stage to 0.18% at stem elongation to full flower. Critical P concentrations for prediction of seed yield were slightly higher (0.05% higher at the rosette stage). A nutrient supply with high P and high N reduced the seed oil concentration of both species; a low P and high N supply reduced the oil concentration in rape seed but increased it in mustard seed.

Critical sulfur concentrations in oilseed rape (Brassica napus) in relation to nitrogen supply and to plant age

1998 ◽  
Vol 38 (5) ◽  
pp. 511 ◽  
Author(s):  
A. Pinkerton
Keyword(s):  
Oilseed Rape ◽  
Seed Yield ◽  
Critical Values ◽  
Sand Culture ◽  
Culture Experiment ◽  
Total N ◽  
N Supply ◽  
S Deficiency ◽  
Time Required ◽  
Time Critical

Summary. Oilseed rape was grown in a sand culture experiment in a glasshouse to derive values for plant testing for the diagnosis of sulfur (S) deficiency and for the prediction of seed yield. Five rates of S, combined factorially with 4 rates of nitrogen (N), maintained constant throughout the experiment, were used to determine critical concentrations of S fractions and ratios (total S, St; sulfate-S, SO4; total N/total S, N/St; SO4/St). The most satisfactory indices of rapeseed S status for diagnosis or prediction were St and SO4. Whole shoots and youngest fully expanded leaves exhibited similar critical values in plants at the rosette stage, and critical values (St = 0.20–0.25%; SO4 = 230–460 mg/kg) changed little with time. Critical values for N/St changed with time, required 2 analyses, and gave no indication of the degree of deficiency when used to predict yield. Critical values of SO4/St depended on N supply, so 3 analyses were needed. It is argued that high critical values reported previously for prediction of seed yield have been obtained when there was a decline in soil-available S and plants relied on S taken up during early growth.

Nitrogen management to optimise canola production in Australia

2016 ◽  
Vol 67 (4) ◽  
pp. 419 ◽  
Author(s):  
R. M. Norton
Keyword(s):  
Seed Oil ◽  
Stem Elongation ◽  
N Uptake ◽  
Oil Quality ◽  
Growth Period ◽  
Yield Potential ◽  
N Budget ◽  
N Supply ◽  
Oil Concentration ◽  
N Management

The expansion of canola production in Australia coincided with an increase in cropping intensity and a reduction in pastures and tillage. These changes mean that nitrogen (N) is often recognised as the most limiting nutrient in canola production, and is the largest single input cost for many growers. Canola responds to added N by producing larger plants that results in a longer leaf area duration, building a larger photosynthetic canopy for seed filling. Although the crop can compensate for poor early growth, a larger canopy is able to compete more effectively against weeds and helps reserve water for crop transpiration rather than soil evaporation. Nitrogen uptake is most rapid during stem elongation, and the N acquired can be remobilised to developing pods and then to seeds. Unlike wheat, N uptake can continue until drought or high temperatures prevent further assimilate supply to the reproductive apex. Data from Australian experiments that measured N uptake over the whole growth period showed that each tonne of seed required ~80 kg N to be taken up, and this forms the basis of a budgeting approach for determining N supply. Typically, added N reduces seed oil concentration at a rate of between –0.03 and –0.13%/kg N. Despite this decline due to added N, oil yield usually increases and the overall value of the crop also increases. Nitrogen has little impact on oil quality or seed glucosinate concentration. The efficiency and effectiveness of N management depends first on selecting a rate appropriate to the water-limited yield potential. Most growers estimate the N rate required using an N budget based on supplying 80 kg N/t less indigenous N supply. The budgeted N can be split over two, three or even more applications with little loss in agronomic efficiency. Splitting application enables growers to make decisions about N when there is more certainty about seasonal conditions. Urea is the most common N source used, and unless there are particular loss processes that are likely to occur, it is cheap and effective. Suggested areas for future N research on canola are to develop tools that can assess in-crop N status, an evaluation of late season N product rate and timing particularly on seed oil concentration, N management for grazed canola, and the development of guidelines to identify, and then address, particular N loss pathways using enhanced efficiency fertilisers.

scholarly journals Gibberellic acid flower formation and stem elongation in Silene armeria.

1973 ◽  
Vol 21 (4) ◽  
pp. 245-255
Author(s):  
S.J. Wellensiek
Keyword(s):  
Gibberellic Acid ◽  
Stem Elongation ◽  
Flowering Plants ◽  
Plant Age ◽  
Flower Formation ◽  
High Concentration ◽  
Short Day ◽  
Long Day ◽  
Silene Armeria

Several selected S. armeria lines differing in their reaction to GA3 were treated with GA3 at various concentrations under short-day (SD) or long-day conditions. With SD treatment one application of GA3 at high concentration (10 000 p.p.m. or greater) induced flower formation in certain lines. Stem elongation increased with GA3 concentration and with plant age and was much greater on flowering plants than on non-flowering ones. [For previous related work see HcA 41, 4400.]. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Recovery of field-grown canola from sulfur deficiency

1996 ◽  
Vol 36 (1) ◽  
pp. 79 ◽  
Author(s):  
PJ Hocking ◽  
A Pinkerton ◽  
A Good
Keyword(s):  
Seed Yield ◽  
Seed Oil ◽  
No Reduction ◽  
Stem Elongation ◽  
Potassium Sulfate ◽  
Growth Stages ◽  
Flower Buds ◽  
S Deficiency ◽  
Oil Concentration ◽  
Seed Yields

Sulfate-sulfur was applied to sulfur (S)-deficient canola at several growth stages in a field experiment at Cargo near Orange, New South Wales. Applications of 0, 10 or 40 kg S/ha (S0, S10 and S40) as mixtures of potassium sulfate and potassium chloride were made at sowing, the 5-6 leaf rosette stage, flower buds visible, stem elongation and first flowering. The plots received either 80 or 160 kg nitrogen (N)/ha at sowing. Plants from the S0 plots showed symptoms of severe S deficiency during rapid stem elongation, and had a 52% reduction in seed yield and a 21% reduction in seed oil concentration compared with the S40 plants. Application of S10 at sowing, or topdressing S-deficient plants with this rate of S, was inadequate because, although seed oil concentrations were normal (39-42%), seed yields were 25% lower than those from plots that received S40. Topdressing S-deficient plants with S40 at either the 5-6 leaf rosette stage, flower buds visible or stem elongation resulted in the same seed yields and seed oil concentrations as obtained when S40 was applied at sowing. However, there was a 15% reduction in seed yield but no reduction in seed oil concentration when the S40 topdressing was delayed until flowering. Although S10 was inadequate to correct the S deficiency, there was no reduction in either seed yield or seed oil concentration when S10 was topdressed as late as flowering, when compared with this rate of S applied at sowing. Seed meal protein levels were increased by the S40 topdressings. Concentrations of S in seed from the S0 and S10 plants were below the critical value of 0.36% for canola. Seed N:S concentration ratios of S-deficient plants were greater than 10, but 7.5 for plants which received adequate S. Total glucosinolates in seed were increased by the application of S, but the levels were still well below the limit set for the canola standard.

Effects of foliar-applied nitrogen fertilizer on oilseed rape (Brassica napus)

2013 ◽  
Vol 153 (1) ◽  
pp. 42-55 ◽  
Author(s):  
C. A. WHITE ◽  
S. E. ROQUES ◽  
P. M. BERRY
Keyword(s):  
Oilseed Rape ◽  
Seed Yield ◽  
Field Experiments ◽  
N Uptake ◽  
Yield Increase ◽  
Uptake Efficiency ◽  
Foliar N ◽  
Seed Protein Concentration ◽  
Oil Concentration ◽  
The Uk

SUMMARYThe aim of the present study was to evaluate the effects on yield, oil concentration and nitrogen (N) uptake efficiency of N fertilizer applied to the foliage of oilseed rape during and soon after flowering. Four field experiments were conducted in the UK during the 2008/09 and 2009/10 seasons which investigated six rates of soil-applied N (ammonium nitrate) ranging from 0 to 280 or 320 kg N/ha with each treatment followed by 0 or 40 kg/ha of foliar N applied as a solution of urea at the end of flowering. Each experiment also investigated five rates of foliar N ranging from 0 to 120 kg N/ha applied at the end of flowering and five timings of foliar N (40 kg N/ha) from mid-flowering to 2 weeks after the end of flowering.Foliar N at 40 kg N/ha applied at the end of flowering significantly increased the seed yield in three of the four experiments. The seed yield increase across all four experiments was 0·25 t/ha (range of 0–0·41 t/ha). In two experiments, the increase in seed yield in response to foliar N occurred irrespective of whether it followed sub-optimal or super-optimal rates of soil-applied N; in one experiment there was a greater response at sub-optimal soil-applied N rates. The foliar N treatment reduced the seed oil concentration by 11 g/kg and increased seed protein concentration by 11 g/kg. Similar yield responses were observed for foliar N applications between mid-flowering and 2 weeks after the end of flowering. The efficiency with which foliar N was taken up into the plant varied between 0 and 100% with an average uptake efficiency across the four experiments of 61%.

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

Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1364 ◽  
Author(s):  
Remigiusz Łukowiak ◽  
Witold Grzebisz
Keyword(s):  
Oilseed Rape ◽  
Field Experiments ◽  
Winter Oilseed Rape ◽  
Brassica Napus L ◽  
N Accumulation ◽  
Yield Increase ◽  
N Supply ◽  
Site Diversity ◽  
Rate Interaction ◽  
N Pool

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.

Productivity and break crop effects of winter-growing oilseeds

1991 ◽  
Vol 31 (5) ◽  
pp. 669 ◽  
Author(s):  
JF Angus ◽  
AFvan Herwaarden ◽  
GN Howe ◽  
Herwaarden AF Van
Keyword(s):  
Water Use ◽  
Stem Elongation ◽  
Wheat Yield ◽  
Indian Mustard ◽  
Canopy Cover ◽  
Shoot Density ◽  
Wheat Crop ◽  
First Year ◽  
Crop Species ◽  
Previous Crop

Productivity, water use and nitrogen (N) use of the oilseeds canola, Indian mustard and linseed were compared with those of wheat and oats in a field experiment in the Riverina. In the following year wheat was grown on the same land and the same attributes were measured. In the first year, wheat productivity exceeded that of all other crops in terms of yield, dry matter production, uptake and the production value (expressed in the common units of the mass of glucose assimilated) of grain and straw. There was no association between productivity and water use, but the cereals had greater canopy cover and, presumably, a greater proportion of the water was transpired rather than evaporated from the soil. In the following year the wheat yield varied with the previous crop species in the order Indian mustard > canola > linseed > oats > wheat. The advantage of the oilseeds to the subsequent wheat crop was evident in terms of shoot density from the stem elongation stage. At the time of maturity, wheat following Indian mustard had extracted more soil water than wheat following canola or wheat following wheat. The early growth advantage to wheat following oilseeds was presumed to be associated with less soil-borne disease. The advantage to wheat following linseed did not persist after anthesis. The advantage to wheat following Indian mustard over wheat following canola appeared to be partly due to greater depletion of subsoil water during the later phases of growth.

Plant phosphorus status has a limited influence on the concentration of phosphorus-mobilising carboxylates in the rhizosphere of chickpea

2005 ◽  
Vol 32 (2) ◽  
pp. 153 ◽  
Author(s):  
Madeleine Wouterlood ◽  
Hans Lambers ◽  
Erik J. Veneklaas
Keyword(s):  
Root Systems ◽  
External Factors ◽  
Sand Culture ◽  
P Deficiency ◽  
Cicer Arietinum L ◽  
Split Root ◽  
Chickpea Cultivar ◽  
Phosphorus Status ◽  
Carboxylate Exudation ◽  
P Supply

Two experiments were conducted to investigate whether carboxylate exudation by chickpea (Cicer arietinum L.) is a response to phosphorus (P) deficiency or a constitutive trait. The effect of P supply on carboxylate concentrations in the plant and in the rhizosphere of chickpea cultivar Heera was studied in a sand culture. Plants were grown in pots supplied with 200 mL of solution containing 0–500 μm P every 3 d. Malonate was the main carboxylate exuded, and the main carboxylate in roots; shoots contained mainly citrate and malate. Contrary to what has been reported for other species, carboxylate concentrations in the rhizosphere decreased only slightly at high P supply, but they were still substantial. The effect of P supply on the rate of exudation was studied in a split-root sand culture. Root systems were split into two pots, one root half received no P and the other half received 200 mL of solution containing 0–500 μm P. The rhizosphere of both root halves contained similar concentrations of carboxylates, even when the plants received a different supply of P. Our results indicate that carboxylate exudation is determined by internal P rather than external factors. The fact that chickpea roots always exude carboxylates indicates that exudation in this species is largely constitutive.

Determinants of oil concentration and seed yield in canola and Indian mustard in the lower rainfall areas of Western Australia

2004 ◽  
Vol 55 (3) ◽  
pp. 367 ◽  
Author(s):  
P. Si ◽  
G. H. Walton
Keyword(s):  
High Temperature ◽  
Water Deficit ◽  
Seed Yield ◽  
Western Australia ◽  
Indian Mustard ◽  
Sowing Date ◽  
Early Flowering ◽  
High Rainfall ◽  
Percentage Points ◽  
Oil Concentration

Oil concentration and seed yield of canola (Brassica napus) are usually low and variable when grown in the lower rainfall areas of Western Australia. This paper identifies determinants of oil concentration and seed yield in these areas. Through a series of cultivar × sowing date experiments at 5 lower rainfall locations and one high rainfall location as comparison, we evaluated the impact of sowing date, cultivar, and location on these 2 key agronomic traits. We also examined relationships between oil concentration, seed yield, and post-anthesis duration, post-anthesis temperature, and post-anthesis rainfall with a view to investigate the adaptive requirements of canola for the lower rainfall areas.Cultivars differed in their capacities to produce oil and seed yield. The ranking of cultivars for oil concentration, and seed yield to a lesser extent, remained constant across sowing dates and locations. Both seed yield and oil concentration decreased with delayed sowing. On average, oil concentration was reduced by 1.1 percentage points and seed yield by 309 kg/ha for every 2 weeks delay in sowing. The magnitude of reduction in oil concentration from delayed sowing was far greater in a low rainfall site at Mullewa than in the high rainfall site at Mt Barker.Later sowings shortened post-anthesis duration. With a given sowing date, early flowering cultivars resulted in longer post-anthesis duration. Oil concentration increased by 1.2 percentage points for a 10-day increase in post-anthesis duration. Both oil concentration and seed yield increased with higher post-anthesis rainfall and lower post-anthesis temperature. The rates of increase were 0.7 percentage points for oil and 116 kg/ha for seed yield for every 10-mm increase in post-anthesis rainfall. The rates of reduction were 0.68 percentage points for oil and 289�kg/ha for seed yield for every 1�C increase in post-anthesis temperature. These relationships suggest that a combination of an early date of sowing with an early flowering cultivar would be essential for the production of high yield and high oil canola in the lower rainfall areas. Indian mustard (B. juncea) showed tolerance to high temperature and water deficit, but the low yield potential makes it uneconomical with early sowing. Further improvement in seed yield could be dependent on increased tolerance of canola to high temperature and water deficit during seed growth and development.

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