Thomas G. Chastain

Here’s an article just published by our seed production team on nitrogen’s effect on seed yield and other seed production characteristics in yellow mustard.  Trials were conducted on this crop over a 3-year period at OSU’s Hyslop Farm by Alyssa DuVal, a former graduate student and current instructor in the department.  Yellow mustard is a potential seed crop for the high rainfall areas of western Oregon and unlike many other Brassica family crops, there is no threat of crossing of yellow mustard with the region’s vegetable seed crops.

Yellow mustard crop pods prior to harvest. (Photo by T.G. Chastain)

This article was published in Agronomy Journal and can be found at the link below:

Duval, A.S., T.G. Chastain, C.J. Garbacik, and D.J. Wysocki.  2017.  Nitrogen affects seed production characteristics in yellow mustard (Sinapis alba L.).  Agron. J. 109:995-1004.

Key findings of the article:

  • Applied N increased seed and oil yield in yellow mustard in a high rainfall environment.
  • Seeds m–2 was the most influential factor in determining seed yield in yellow mustard.
  • Applied N increased height, biomass, tissue N content, leaf area index, and crop growth rate.

Thomas G. Chastain

Several scales have been constructed for use in assigning developmental stages to crop plants.   The BBCH (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie) scale is used to ascertain the developmental stages of crops and is based on the Zadoks scale for cereals but has been standardized and extended to many other crops including dicots.

The uniform nature of the BBCH scale has encouraged the wide-spread use of this system by agronomists and by agricultural practitioners alike.  One advantage of the BBCH scale is the simplicity of staging of crop plants because only one scale (with minor modification) is needed for multiple species.

Ten principal stages form the basis for the scale in each crop.  Below is a table showing the adaptation of the scale for grass seed crops.

Stage Description – BBCH scale
0-9 Seed germination/bud development
10-19 Leaf development
20-29 Tiller development
30-39 Stem elongation
40-49 Booting
50-59 Inflorescence emergence/development
60-69 Flowering/pollination
70-79 Seed development
80-89 Seed maturation and harvest
90-99 Senescence

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A new nutrient management guide for tall fescue seed crops has been published by OSU’s seed production research and extension team.  The 42-page publication (EM 9099) is a product of many years of  field work in tall fescue seed crops by the members of the research and extension team.

Tall fescue cover

The nutrient management guide covers the impacts of application of nutrients on seed yield, seed yield components, crop growth and development, plant growth regulator use, pests, and others.  Extensive use of tables, figures, and appendices supplement this comprehensive guide to tall fescue seed crop nutrient management.

The publication can be accessed at the link below:

Tall Fescue Grown for Seed: A Nutrient Management Guide for Western Oregon, EM 9099

Thomas G. Chastain

Why is lodging important in grass seed crops?

Under certain conditions, the tiller cannot support the weight of the developing inflorescence and seed. The tiller lodges or falls to the ground, especially when there are high levels of nitrogen fertilizer and soil moisture present (Fig. 1). Both conditions are common in Oregon’s commercial grass seed production fields in the spring.

Figure 1. Lodging in ryegrass. (T.G Chastain photo)

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A new publicPicture1ation on nutrient management in perennial ryegrass seed crops has just been released by OSU’s grass seed production research and extension team.  The publication (EM 9086) is a product of many years of  field work in grass seed crops by the members of the research and extension team.  The nutrient management guide covers the impacts of application of nutrients on seed yield, seed yield components, crop growth and development, plant growth regulator use, pests, and others.  Extensive use of tables, figures, and appendices supplement this comprehensive work on perennial ryegrass nutrient management.

The publication can be accessed at the link below:

Perennial Ryegrass Grown for Seed (Western Oregon) EM 9086

Here’s  a new article from our research group on trinexapac-ethyl plant growth regulator (PGR) effects in perennial ryegrass seed crops that will be published in Field Crops Research.  This PGR is marketed as Palisade, Moddus, and several generic products.  The trials were conducted from 1998 to 2012 at OSU’s Hyslop Farm.

Figure 1.  Lodging in ryegrass.
Figure 1. Lodging in ryegrass.

The study reports several important findings:

  • Application of trinexapac-ethyl PGR reduced stem length and controlled lodging in perennial ryegrass across nine diverse lodging environments in the Willamette Valley of Oregon.
  • Trinexapac-ethyl PGR consistently increased seed yield and harvest index in perennial ryegrass regardless of the severity of lodging.
  • Timing trinexapac-ethyl applications between BBCH stages 32 and 51 produced the best seed yield results.
  • Seed yield increases resulting from trinexapac-ethyl application were attributable to a greater number of seeds spikelet-1 (seed number) and improvements in seed set.

 

Click on the citation below to go to the article:

Chastain, T.G., W.C. Young III, T.B. Silberstein, and C.J. Garbacik.  2014.  Performance of trinexapac-ethyl on seed yield of Lolium perenne in diverse lodging environments.  Field Crops Research 157:65-70.