Phloem transport of amino acids in two Brassica napus L. genotypes and one B. carinata genotype in relation to their seed protein content

SUMMARYCanola (Brassica napusL.) meal is widely used in animal feed as a protein source, and its quality relies on protein and amino acid content. However, little information is available regarding amino acid regulation in canola seed with nitrogen (N) application. The present study is aimed to evaluate the effect of N rate and genotype on canola seed amino acid concentrations under field conditions. A split-plot design comprising four N rates (0, 120, 240 and 360 kg N/ha) and three genotypes differing in seed protein content were used in 2010/11 and 2011/12. The results showed that increasing N rate decreased seed oil content linearly but increased seed protein content in all of the genotypes. The total amino acid concentration and absolute concentrations of individual amino acids in canola seed also improved significantly with the N rates in all of the genotypes. Regarding the proportions of amino acids, a group that included glutamic acid (Glu), proline (Pro) and arginine (Arg) dominated and occupied > 0·30 compared with other amino acids. The ratio of amino acids in this group increased by 8·3% with 360 kg N/ha compared with the control. However, the proportions of the other amino acids showed negative responses to the N rates. The results of regression analysis of the responses of individual amino acids to N rate indicated that Glu, Pro and Arg had a greater improvement potential with application of N fertilizer, as revealed by higher slopes in the linear equations compared with the other amino acids. Additionally, the concentrations of sulphur-containing amino acids, methionine and cysteine, were also a potential target for improving with N application because these are always deficient in major crops. In conclusion, N application cannot only improve seed protein content but also enhance deposition of amino acids such as Glu, Pro and Arg.

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Species and varietal differences in the proteins of rapeseed

Canadian Journal of Botany ◽

10.1139/b69-097 ◽

1969 ◽

Vol 47 (5) ◽

pp. 679-685 ◽

Cited By ~ 28

Author(s):

A. J. Finlayson ◽

R. S. Bhatty ◽

C. M. Christ

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Brassica Napus ◽

Amino Acid Composition ◽

Protein Content ◽

Acid Composition ◽

Brassica Campestris ◽

Sulfur Deficiency ◽

Brassica Napus L ◽

Sulfur Containing

Two proteins, previously described by the authors as BI (S020, buffer 12 S) and AIVS (S020, w 1.7 S) have been isolated from eight varieties of rapeseed belonging to Brassica campestris L. and Brassica napus L. species. These proteins have similar chromatographic and electrophoretic characteristics but differ in amino acid composition, particularly with regard to the sulfur-containing amino acids. One of the rapeseed samples was obtained from plants grown on sulfur-deficient soil. The sulfur deficiency produced, in the mature seed, a much reduced protein content and appeared to affect the structure of the protein BI.

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Placement, rate and source of N, seedrow opener and seeding depth effects on canola production

Canadian Journal of Plant Science ◽

10.4141/p03-174 ◽

2004 ◽

Vol 84 (3) ◽

pp. 719-729 ◽

Cited By ~ 18

Author(s):

S. S Malhi ◽

K. S Gill

Keyword(s):

Protein Content ◽

Oil Content ◽

Seed Protein ◽

Negative Impact ◽

N Uptake ◽

N Fertilizer ◽

Yield Response ◽

Silty Clay ◽

Seed Protein Content ◽

Brassica Napus L

Seedrow-placement of N fertilizer can save money and time, but it can cause reduced emergence and yield. From 1998 to 2000, a field experiment was conducted on a silty clay loam (Black Chernozem) soil at Melfort, Saskatchewan. The objectives were to determine the influence of placement, rate and source of N, seedrow opener and seeding depth on the emergence, yield, N uptake, and seed protein and oil content of canola (Brassica napus L. ‘Quest’). The treatments were optimum (1.5 cm) and deep (4.5 cm) seeding depths in two main plots with 17 subplots of different combinations of N sources [urea and ammonium nitrate (AN)], rates (0, 40, 80 and 120 kg N ha-1) and placements (sideband and seedrow) using two seedrow openers (knives – 2 cm spread, and shovels – 20 cm spread). Sidebanding of 40, 80 and 120 kg N ha-1 and seedrow placement of 40 kg N ha-1 increased yield, N uptake and seed protein content, had no detrimental effect on emergence, and reduced seed oil content. Compared to sidebanding, seedrow placement of 80 and 120 kg N ha-1 generally reduced emergence, yield and N uptake, with relatively severe effect at higher N rate, but had no effect on seed protein and oil content. The yield and N uptake of canola responded up to 120 kg N ha-1 with sidebanding compared to 40 kg N ha-1 for yield and 80 kg N ha-1 for N uptake with seedrow placement. Deep seeding reduced emergence, yield and N uptake in many cases, had no effect on seed protein content and reduced oil content in some treatments. At low rates of N, emergence was generally better with knives, while shovels tended to be superior at higher rates of seedrow-placed N. In general, the negative impact of seedrow placement compared to sideband placement of N was more severe with deeper seeding, higher N rate and narrower width of seedrow placement band. In summary, the findings indicated that practices that placed seed and fertilizer in a way that maximized canola emergence and minimized seedling damage from fertilizer, consistently optimized seed yield response to N fertilizer. Key words: Canola, N placement, N rate, N source, seeding depth, seedrow opener

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Shikimate Dehydrogenase ‐1 2 Allozyme as a Marker for High Seed Protein Content in Rice

Crop Science ◽

10.2135/cropsci1990.0011183x003000040036x ◽

1990 ◽

Vol 30 (4) ◽

pp. 937-940 ◽

Cited By ~ 5

Author(s):

V. V. Shenoy ◽

D. V. Seshu ◽

J. K. S. Sachan

Keyword(s):

Protein Content ◽

Seed Protein ◽

Seed Protein Content ◽

Shikimate Dehydrogenase

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Modeling the Competitive Effect of Euphorbia dracunculoides and Astragalus sp. in Zero Input Rainfed Chickpea

Planta Daninha ◽

10.1590/s0100-83582018360100021 ◽

2018 ◽

Vol 36 (0) ◽

Author(s):

R.M. IKRAM ◽

A. TANVEER ◽

R. MAQBOOL ◽

M.A. NADEEN

Keyword(s):

Protein Content ◽

Critical Period ◽

Field Experiments ◽

Seed Protein ◽

Yield Loss ◽

Seed Protein Content ◽

Yield Losses ◽

Competition Period ◽

Crop Competition ◽

Weed Removal

ABSTRACT: Brown chickpea (Cicer arietinum L.) is one of the two chickpea types grown in Pakistan and other countries. The critical period for weed removal in a rainfed chickpea system is an important consideration in devising weed management strategies. Field experiments were conducted in the winter season of 2011 and 2012 to determine the extent of yield loss with different periods of weed crop competition. Seven weed crop competition periods (0, 45, 60, 75, 90, 105 and 160 days after sowing - DAS) were used to identify the critical period for weed removal in rainfed chickpea. Experimental plots were naturally infested with Euphorbia dracunculoides and Astragalus sp. in both years. Individual, composite density and dry weights of E. dracunculoides and Astragalussp. increased significantly with an increase in the competition period. However, yield and yield-contributing traits of chickpea significantly decreased with an increase in the competition period. Chickpea seed yield loss was 11-53% in different weed crop competition periods. Euphorbia dracunculoides and Astragalus sp. removed 39.9 and 36.9 kg ha-1 of N, 9.61 and 7.27 kg ha-1 of P and 38.3 and 36.9 kg ha-1 of K, respectively. Season long weed competition (160 days after sowing) resulted in 19.5% seed protein content compared with 24.5% seed protein content in weed-free chickpea. A Logistic equation was fitted to yield data in response to increasing periods of weed crop competition. The critical timing of weed removal at 5 and 10% acceptable yield losses were 26 and 39 DAS, respectively. The observed critical period suggests that in rainfed chickpea, a carefully timed weed removal could prevent grain yield losses.

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