The effects of weather, seed rate and cultivar on lodging and yield in winter wheat

Abstract

SUMMARYWinter wheat cultivars Apollo, Hornet, Longbow and Norman were each sown at 50, 100, 200, 400, 800 and 1600 seeds/m2 in a field experiment conducted in Northern Ireland over the 1989/90 crop year. No growth regulators were applied and the wheat received 178 kgN/ha top-dressing in the spring. Hourly rainfall, windspeed and wind direction data were recorded and lodging was visually assessed from the end of May to harvest. Lodging first occurred in the 1600 seed-rate plots as the ears were emerging in early June and then progressively increased in the 800, 400 and 200 plots during June, July and August. Lodging did not occur suddenly but took several hours, with the stems first lying at an angle before lodging completely. Stem buckling or breakage did not appear to be the principal form of structural failure. The longest strawed cultivar, Longbow, lodged most severely. The shorter-strawed Norman also lodged badly in contrast with Hornet which had a similar straw length. Apollo, which was taller than Norman and Hornet and produced more ears per square metre than the other cultivars, lodged least but tended to lean at c. 30° from the vertical. Lodging occurred during or within 24 h of periods of rainfall which, in many cases, coincided with windspeeds at crop height averaging > 25 km/h and occasionally > 50 km/h. Lodging also occurred following rainfall when the windspeed did not exceed 16 km/h. The grain yield was negatively correlated with the average lodging from ear emergence to harvest, there being a 1 t/ha decline in yield for each 10% increase in average area lodged. The 50 and 100 seed-rate plots yielded 10 t/ha and had little or no lodging. The decline in yield with increased lodging and seed rate was attributed to the effect of lodging rather than to seed rate and was associated with a fall in the number of grains/ear and 1000-grain weight from 56 and 53·5 g at the lowest seed rate to 15 and 42·7 g at the highest, respectively. A comparison of the plants from lodged and unlodged plots of the 1600 and 800 seed rates, and subsequently of the 800 and 400 seed rates, indicated that at the higher seed rate, lodged plots had less fresh weight per unit area, basal internodes with smaller diameters, fewer support roots per stem, and a lower root dry weight per stem.

Chemical Regulators of Gibberellin Status and Their Application in Plant Production

“…The use of anti-lodging products in wheat has been banned in Sweden in 1987 in order to reduce production intensity and, thereby, lower the negative impacts agriculture may have on the environment. Not least due to this, a reduction of wheat productivity by approximately 25% has resulted in comparison to countries with similar production Pinthus, 1973;Anderson, 1979;Jung and Rademacher, 1983;Hoffmann, 1992;Easson et al, 1993;Berry et al, 2004;Baker et al, 2014 and after results of BASF field trials). conditions such as Denmark, Germany or the UK (data from FAOSTAT).…”

“…Therefore, products containing trinexapac-ethyl and prohexadione-calcium or the ethylene-releasing ethephon are preferentially used to reduce the risk of lodging in this crop. Additional information on lodging in small grains and on the use of anti-lodging agents in cereal production can be found in Easson et al (1993), Berry et al (2004), Rademacher (2010b), Berry and Spink (2012) and Baker et al (2014). Different anti-lodging products are listed in Table 12.2.…”

Effect of dose and timing of application of different plant growth regulators on lodging and grain yield of a Scottish landrace of barley (Bere) in Orkney, Scotland

“…This outcome suggested that the mechanism by which PGR increased resistance to lodging may not be related to StL alone. Other lodging related stem traits such as SD (Easson et al, 1993), SWCM (Zuber et al, 1999) as well as EW (Tripathi et al, 2003) were investigated in Trial 2. It has been reported that a higher SD is an indication of lodging resistance (Mukherjee et al, 1967) but the Trial 2 results showed no evidence that PGRs affected SD.…”

Grain yield and associated photosynthesis characteristics during dryland winter wheat cultivar replacement since 1940 on the Loess Plateau as affected by seeding rate

“…Seven wheat cultivars released from 1940 to 2004 that were once widely grown on the Loess Plateau were grown in field experiments during the 2011-2012 growing season at the Changwu experiment station in China using three seeding rates (100, 250, and 350 seeds m growth (Gooding et al, 2002) and lodging (Easson et al, 1993). No marked differences are reported among varieties regarding the responses of grain yields to variations in plant density (Arduini et al, 2006;Brian et al, 2011).…”