ICM experiments with barley in Saskatchewan

Non-Peer Reviewe

Tolerance of HY320 and hard red spring wheat to soil incorporated herbicides

Non-Peer ReviewedField experiments were conducted at Kernen and Goodale farms near Saskatoon in 1985 and 1986 to compare the tolerance of HY320 and Katepwa spring wheats to triallate and trifluralin herbicides. HY320 and Katepwa were seeded at each site in both years at 90 and 67 kg/ha respectively. 1985 experiments were conducted at one seeding depth. In 1986, three seeding depths were examined at each site. Each herbicide was applied after seeding at 1× and 2× the maximum recommended rate. A tank-mixture of the two products was also tested at 1× and 2× rates. Incorporation to a depth of approximately 5 cm was accomplished using two passes of a diamond harrow. Treatments were replicated four times. In 1985, significant differences in yield and plant stand were1measured for Katepwa at Goodale and Kernen, respectively. There were no significant differences in HY320 yield or plant stand and it out-yielded Katepwa at both sites. Significant differences in yield resulted from the herbicide treatments in both varieties and sites in 1986. Highest yields were recorded in the untreated checks and the lowest in the 2× tank-mix treatments. As in 1985, HY320 out-yielded Katepwa at both sites. In 1986, shallow seeding resulted in reduced yields of both Katepwa and HY320. The tolerance of HY320 to these products appears to be similar to that of Katepwa

The effect of dilution water quality on herbicide efficacy

Non-Peer ReviewedThe antagonistic effect of Ca2+ and Mg2+ ions on the efficacy of glyphosate (Roundup) has been well documented for some time but there is relatively little information available on the effect of other ions on glyphosate or other herbicides. Field trials were conducted at Saskatoon in 1989 and 1990 to determine the effect of dilution water ion content on the efficacy of several herbicides. Water sources examined were: Saskatoon (surface, fresh, low mineralization), Goodale (artesian well, hard, high Ca2+ and Mg2+), Zelma (well, hard, high Fe3+), Outlook (well, soft, high Na+), Unity (well, soft, medium HCO3-), Maple Creek (well, soft, high HCO3-) Recommended and less than recommended rates of selected herbicides were applied in four replicate field trials using standard flat fan nozzles that delivered 130 L/ha (1989) or 110 L/ha (1990) of spray mixture. Herbicide X water combinations that have resulted in reduced weed control as compared to Saskatoon water as the check are: glyphosate (Roundup) X Goodale or Zelma, sethoxydim (Poast) X Unity or Maple Creek, clethodim (Select) X Unity or Maple Creek, 2,4-D amine X Goodale, Outlook or Unity. Imazamethabenz (Assert) was not affected initially but plants treated with water from Unity or Maple Creek recovered more rapidly than those treated with Saskatoon water. Fenoxaprop-ethyl (Excel), 2,4-D ester, and glufosinate ammonium (Ignite, Harvest) were not affected by water source

Response of barley cultivars to plant growth regulators

Non-Peer Reviewe

The effect of seeding depth and soil incorporated herbicides on spring wheat

Non-Peer Reviewe

Weed management systems in spring wheat

Non-Peer ReviewedTrials were conducted at two locations near Saskatoon during 1989 to compare the effectiveness of three weed management systems in spring wheat. A conventional weed management system (pre- and post-emergent herbicides plus tillage) was compared to a conservation weed management system (herbicides and no tillage) and a cultural system (tillage and no herbicide). Each system was used in Katepwa spring wheat seeded at early (May 11) and late (May 29) seeding dates. Herbicides applied prior to crop emergence were pre-selected. Post-emergent herbicides were selected on the basis of the weed populations at each site. The Kernen site was a heavy clay soil which had been summerfallowed the previous year. The Sutherland site was a clay loam soil which was seeded to wheat during 1988. A heavy population of green foxtail (Setaria viridis) dominated the Sutherland site. The Kernen site had a light population of annual broad-leaved weeds. Average grain yields at both sites were in the range of 2000 kg/ha. However, none of the three management systems resulted in increased grain yield. Early seeding resulted in significantly higher weed populations and grain yields at both sites. The average cost of seedbed preparation and weed control operations showed that the conventional, conservation and cultural systems ranked from highest to lowest, respectively. In the absence of a yield response to any system during 1989, the check plots produced the highest net return

Pre-emergence tillage in field pea effective, but timing critical

Non-Peer ReviewedOn the semi-arid prairies, it is generally recommended to seed field pea early and at a depth of 4 to 7.5 cm. Crops that emerge before weed emergence are more competitive than crops emerging at the same time or after weed emergence. Delayed seeding to control late-emerging weeds and seeding at shallower depths to promote rapid emergence may be an alternative weed management strategy. The objective of this experiment was to identify combinations of seed date, seed depth, and pre-emergent weed control to optimize yield of field pea grown without the use of herbicides

Field pea seed residues: the potential for low cost weed control

Non-Peer ReviewedPlant growth suppression trials were undertaken with soil sampled 18 mo apart (2008, 2009) from two locations affected by field pea seed residues. Test plant species were grown in the residue-affected soil and compared to residue-unaffected soils, sampled from nearby fields. Germination was either fully inhibited or emergence delayed by more than one week in residue-affected soil. Dry matter accumulation of test species grown in residue-affected soil was significantly reduced compared to dry matter of these species grown in unaffected soil (P <0.0001). Canola and field pea were inhibited more than wheat and green foxtail over both years. Greenhouse trials also revealed that germination of wild oats was inhibited in the residue-affected soils, although overall, wheat and grassy weeds were less affected than dicots. Significant reductions of weed species diversity and abundance were correlated to residue-affected soils (P <0.0001) when compared to control soils using multi-response permutations procedures. In bioassays in sterile media, germination of wheat and canola seed was inhibited, using aqueous extracts of weathered pea seeds or extracts of the residue-affected soil. An allelopathic response was proposed to explain these results

Seasonal weed response to integrated crop management systems

Non-Peer ReviewedWeed plant density was monitored to determine the effect of various integrated crop management systems on weed population levels and evaluate the efficacy of the various management practices. The management systems studied primarily varied tillage and herbicide inputs. Weed plant density was determined in spring, prior to in-crop management and after in-crop management in each year of the study. Also, weeds were counted after in-crop management prior to the establishment of the management systems. Multivariate analyses were used to determine the response of the weed communities to the management systems. Principal response curves were used to illustrate seasonal fluctuations and trends in weed densities. Stinkweed, lamb’s-quarters, wild buckwheat, redroot pigweed, wild mustard and Russian thistle are best controlled with in-crop herbicide applications. These species increased over time in the no herbicide high tillage system and low herbicide systems. Winter annuals, perennials and early spring annuals were found to increase in the lower herbicide zero-tillage systems. These species tended to be found in high densities in the spring and not effectively controlled in-crop