Impact of tillage system, rotation and fungicide application on seed yield and protein content of wheat and field pea

Non-Peer ReviewedThe impact of tillage system, increasing broadleaf crop rotation frequency and foliar fungicide use on diseases, seed yield and protein content of wheat and field pea were determined in the second cycle of three 4-year rotations at Melfort from 1998 to 2001. A 4-replicate split-split plot design was used with three tillage systems (zero tillage (ZT), minimum tillage (MT) and conventional tillage (CT)) as main-plots, three rotations (1. barley-canola-wheat- barley; 2. barley-pea-wheat-canola; and 3. canola-pea-flax-barley) as sub-plots and foliar fungicide treatments (treated or untreated) as sub-sub plots. Tillage system had little impact on diseases in either wheat or field pea. In the drought year of 2001, seed yield of wheat was greater under ZT or MT than under CT. The trend for field pea was similar in 2001. In other years there was no difference in yield for either crop among tillage systems . Protein content of wheat was often greater under ZT than under MT and/or CT, but tillage system did not have a consistent effect on protein content in field pea seed. Rotation was not a major factor in disease severity of either wheat or field pea. Rotation had an effect on seed yield of field pea only in 2001, but there was no effect on seed yield of wheat in any year. For wheat, protein content in seed was greater in 3 of the 4 years (1998, 1999 and 2001) when it followed field pea than when it was grown after canola. Rotation had little effect on protein content in seed of field pea. Foliar fungicide application had the greatest impact on disease control and seed yields, although benefits varied from year to year. Fungicides increased field pea yield by 32 and 16% in 1998 and 2000, respectively and wheat yield by 19, 13 and 9% in 1998, 1999 and 2000, respectively. There was no yield increase for either crop by application of foliar fungicide in the drought year of 2001. For wheat, protein content in seed decreased with fungicide application, but the effect was significant only in 1998. For field pea, protein content in seed decreased with fungicide application in 1998 and 2000, most likely due to a dilution effect from increased seed production. In summary, foliar fungicides had the greatest impact of the factors examined to reduce plant disease symptoms and increase seed yield of either crop, however the magnitude of the yield increase varied among crop years depending on environmental conditions. Most importantly, the study indicated that increasing the frequency of broadleafed crops in a rotation did not result in increased diseases or lower yield of field pea

Impact of tillage system, rotation, and fungicide application on field crop production (1998-2001)

Non-Peer ReviewedThe impact of tillage, rotation, and fungicides on diseases and seed yield of wheat, barley, field pea, flax and canola was determined in the second cycle of 3, 4-year rotations at Melfort between 1998 and 2001. A 4-replicate split-split plot design was used with tillage systems (conventional, minimum and zero) as main-plots, three rotations (1 - canola, wheat, barley, barley; 2 - canola, barley, pea, wheat; and 3 - canola, pea, flax, barley) as sub-plots and fungicide treatments (treated or untreated) as sub-sub plots. Tillage system had little impact on diseases of any crop, although yield was greater under zero tillage than conventional or minimum tillage for most crops in the drought year of 2001. Rotation was not a major factor in disease severity of any of the crops except barley in Rotation 1, where it was grown for two consecutive years. Rotation did have an impact on yield of barley, which followed flax in Rotation 3 due to the water use of flax in 2000, which reduced barley yield in the drought year of 2001. Fungicide application had the greatest impact on disease control and yields although benefits varied among crop species and environments

Biomass accumulation and nutrient uptake of cereals at different growth stages in the parkland region of Saskatchewan

Non-Peer ReviewedField experiments were conducted with spring wheat (cv. AC Barrie - CWRS and cv. AC Taber - CPS), barley (cv. AC Oxbow - malt and cv. AC Lacombe - feed) and oats (cv. CDC Boyer or CDC Pacer) in 1998 and 1999 at Melfort, Saskatchewan, Canada, to determine biomass accumulation and nutrient uptake in cereal crops at different growth stages, and their relationship. All cereal crops followed a similar pattern of biomass and nutrient accumulation, which increased at early growth stages, reached at maximum and then decreased at late growth stages. Cereal crops usually reached their maximum biomass at late milk to full ripening stages (72-90 days after emergence), although some cultivars had a several days difference between the two years. Maximum biomass accumulation rate was 164-204 kg ha-1d-1 for wheat, 211-308 kg ha-1d-1 for barley and 185-217g ha-1d-1 for oats. Maximum uptake of nutrients usually occurred at beginning of flower to late milk (63-82 days after emergence) in both years. Maximum accumulation rate of N, P, K and S was 2.0-4.7, 0.3-0.4, 2.4-5.1 and 0.3-0.5 kg ha-1d-1 for wheat, 2.4-5.2, 0.3-0.5, 3.1-7.6 and 0.4-0.8 kg ha-1d-1 for barley, and 2.7-3.6, 0.3, 4.2-4.7 and 0.4-0.5 kg ha-1d-1 for oats, respectively. Both seed yield and nutrient uptake were lower in 1999 than in 1998, due to differences in weather conditions in the growing season in the two years. In summary, maximum nutrient accumulation rate occurred earlier than maximum biomass accumulation rate, and maximum nutrient uptake occurred earlier than maximum biomass. This indicates that in order to get high seed yields, there should be sufficient supply of nutrients to ensure higher nutrient uptake rate at tillering to stem elongation growth stage first, then a higher biomass accumulation rate at early to late boot growth stage, a greater nutrient uptake at beginning of flower to late milk growth stage, and a greater biomass at late milk to full ripening growth stage. This also suggests that sufficient supply of nutrients from soil/fertilizers at early growth stages is of great importance for high-yield crop production systems

Biomass accumulation and nutrient uptake of oilseeds at different growth stages in the parkland region of Saskatchewan

Non-Peer ReviewedField experiments were conducted with canola (Brassica napus and B. rapa, cv. Quantum and Tobin), mustard (cv. AC Vulcan) and flax (cv. Norlin) in 1998 and 1999 at Melfort, Saskatchewan, Canada, to determine biomass and nutrient accumulation in oilseeds at different growth stages and their relationship to seed yield. In general, all oilseed crops followed a similar pattern in biomass accumulation and nutrient uptake, which increased at early growth stages, reached maximum and then decreased at late growth stages. Oilseed crops usually reached their maximum biomass at medium to end of pod forming growth stages (74-80 days after emergence), although Quest canola cultivar had a several day delay at early ripening stage (84 days after emergence) in 1998. Maximum biomass accumulation rate was 146-190 kg ha-1d-1 for canola, 158-182 kg ha-1d-1 for mustard and 174-189 kg ha-1d-1 for flax. Maximum nutrient uptake usually occurred at flowering to seed filling stage (59-85 days after emergence. Maximum nutrient uptake rate for N, P, K, S and B, respectively, was 2.3-4.5, 0.3-0.5, 2.5-5.7, 0.7-1.1 and 0.005-0.008 kg ha-1d-1 for canola, 2.3-3.9, 0.4-0.5, 2.6-4.9, 1.2-1.4 and 0.006-0.008 kg ha-1d-1 for mustard and 3.2-4.0, 0.3-0.4, 2.9-4.1, 0.3-0.5 and 0.004-0.009 kg ha-1d-1 for flax. Both seed yield and nutrient uptake in seed were lower in 1999 than in 1998, due to differences in weather conditions in the growing season in the two years. In summary, maximum nutrient accumulation rate occurred earlier than maximum biomass accumulation rate, and maximum nutrient uptake was earlier than maximum biomass. This indicates that in order to get high seed yields, there should be sufficient supply of nutrients to plants to ensure higher nutrient uptake rate at side shooting to bud forming stage, and then a greater biomass accumulation rate at early to late bud forming stage. This further suggests that adequate supply of nutrients from soil/fertilizers at early growth stages is of great importance for high-yield crop production systems

Biomass accumulation and nutrient uptake of pulses at different growth stages in the parkland region of Saskatchewan

Non-Peer ReviewedField experiments was conducted with pea (cv. Carnival and Swing), lentil (cv. Laird and CDC Milstone) and bean (cv. CDC Camino) in 1998 and 1999 at Melfort, Saskatchewan, Canada, to determine biomass and nutrient accumulation in pulses at different growth stage and their relationship to seed yield. Pulse crops followed a similar pattern in dry matter and nutrient accumulation, which increased at early growth stages, reached maximum and then decreased at late growth stages. Pulse crops usually reached their maximum biomass at medium pod forming to early seed filling stages (75-82 days after emergence). Maximum biomass accumulation rate was 175-215 kg ha-1d-1 for pea, 109-140 kg ha-1d-1 for lentil and 53 kg ha-1d-1 for bean. Maximum uptake of nutrients usually occurred at flowering to seed filling stages (59-85 days after emergence). Maximum accumulation rate of N, P, K and S, respectively, was 4.6-4.9, 0.4-0.5, 5.0-5.3 and 0.3 kg ha-1d-1 for pea, 2.4-3.8, 0.2-0.3, 2.0-3.4 and 0.2 kg ha-1d-1 for lentil and 1.1, 0.1, 1.5 and 0.1 kg ha-1d-1 for bean. Both seed yield and nutrient uptake in seed were lower in 1999 than in 1998, due to differences in weather conditions in the growing seasons in the two years. In summary, maximum nutrient accumulation rate occurred earlier than maximum biomass accumulation rate, and maximum nutrient uptake was earlier than maximum biomass. This indicates that in order to get high seed yields, there should be sufficient supply of nutrients to plants to ensure higher nutrient uptake rate at side shooting to bud forming stage, and then a greater biomass accumulation rate at early to late bud forming stage. This further suggests that adequate supply of nutrients from soil/fertilizers at early growth stages is of great importance for high-yield crop production systems

Management for optimum yield of open pollinated and hybrid canola

Non-Peer ReviewedNewer open pollinated (O.P.) and hybrid canola varieties provide higher yield potential but the management strategies necessary to achieve optimum yield are not well understood. To better understand the levels of inputs required to optimize yield and to enhance producers ability to optimize return on their investment a three year study was conducted at Melfort, Indian Head, and Scott during 1999, 2000 and 2001 with the following objective. Objective: To evaluate the effect of seeding rate, fertilizer addition and fungicides on the optimum yield potential of hybrid and open pollinated canola in the Thick Black, Thin Black and Dark Brown Soil Zones

Nitrogen response and nitrogen use efficiency of high yielding canola cultivars

Non-Peer ReviewedSeveral new canola varieties have much higher yield potential than those grown in the past. For example, the yield potential of highest yielding varieties listed in the Varieties of Grain Crops booklet for 2001, published by Saskatchewan Agriculture and Food are as much as 35% greater than for the check variety AC Excel. One question that arises is whether such varieties require greater inputs of fertilizer nutrients, particularly nitrogen (N), to realize optimum economic returns

Structural and Magnetic Properties of Trigonal Iron

First principles calculations of the electronic structure of trigonal iron were performed using density function theory. The results are used to predict lattice spacings, magnetic moments and elastic properties; these are in good agreement with experiment for both the bcc and fcc structures. We find however, that in extracting these quantities great care must be taken in interpreting numerical fits to the calculated total energies. In addition, the results for bulk iron give insight into the properties of thin iron films. Thin films grown on substrates with mismatched lattice constants often have non-cubic symmetry. If they are thicker than a few monolayers their electronic structure is similar to a bulk material with an appropriately distorted geometry, as in our trigonal calculations. We recast our bulk results in terms of an iron film grown on the (111) surface of an fcc substrate, and find the predicted strain energies and moments accurately reflect the trends for iron growth on a variety of substrates.Comment: 11 pages, RevTeX,4 tar'd,compressed, uuencoded Postscript figure

Resolving local and global kinematic signatures of satellite mergers with billion particle simulations

Large scale structure and cosmolog