Cereal lodging

Plant growth regulators (PGRs) are synthetic compounds which can be used to reduce lodging in several crop species. 

Plant growth regulators (PGRs) are synthetic compounds which can be used to reduce lodging in several crop species including cereals and oilseed rape. They are most commonly used for this purpose in north and western European countries and in North America (Rademacher, 2000). In the UK, about 90% of the winter wheat is treated with PGRs.

PGRs can be classified into two main groups: inhibitors of gibberellic acid biosynthesis and ethylene-releasing compounds. The most commonly used inhibitors of gibberellic acid biosynthesis in cereal crops are chlormequat chloride, mepiquat chloride, trinexapac-ethyl, and prohexadione-calcium [Rademacher, 2000]. Ethephon is the most commonly used ethylene-releasing compound on cereals [Rademacher, 1993]. Plant growth regulators have been shown to be a cost-effective method of reducing the incidence of lodging. PGRs applied before the emergence of the ear reduced lodging in almost all of the vast number of published experiments that have studied their effect and in which lodging occurred, with reductions in the percentage area lodged of anything up to 70% [Berry et al., 2004]. The primary mechanism by which PGRs have been shown to reduce lodging risk is by reducing crop height, with height reductions of up to 40% [Berry et al., 2004]. The variation on plant height reduction is probably caused by interactions between the type of active ingredient, the cereal species together with the stage of plant development, and the environmental conditions when the chemical is applied. No evidence has been found for PGRs to increase the strength of the stem or of the anchorage system [Berry et al., 2000; Crook et al., 2000], although it must be recognized that only two studies have investigated the effects of PGRs by directly measuring stem and anchorage strength. Chlormequat has been shown to be effective at reducing lodging in winter and spring wheat, oats, and rye but less effective on barley [Humphries (1968; Matthews & Thompson, 1983)]. Barley undergoes large height reductions in response to a mixture of ethephon and mepiquat chloride [Herbert, 1982; Stanca, 1979].

Berry PM, Sterling M, Spink JH, Baker CJ, Sylvester- Bradley R, Mooney S, Tams A, Ennos AR (2004) Understanding and reducing lodging in cereals. Adv Agron 84:215–269

Berry PM, Griffin JM, Sylvester-Bradley R, Scott RK, Spink JH, Baker CJ, Clare RW (2000) Controlling plant form through husbandry to minimise lodging in wheat. Field Crops Res 67:59–81

Crook MJ, Ennos AR (1995) The effect of nitrogen and growth regulators on stem and root characteristics associated with lodging in two cultivars of winter
wheat. J Exp Bot 46:931–938

Herbert CD (1982) Growth regulation in cereals chance or design? In: McLaren JS (ed) Chemical manipulation of crop growth and development. Butterworth Scientific, London, pp 315–327

Humphries EC (1968) CCC and cereals. Field Crop Abstr 21:91–99

Matthews S, Thompson WJ (1983) New roles for growth regulators in cereal production. In: Wright DW (ed) The yield of cereals. Royal Agricultural Society of England, London, pp 25–31

Rademacher W (2000) Growth retardents: effects on gibberellin biosynthesis and other metabolic pathways. Annu Rev Plant Physiol Plant Mol Biol 51:501–531

Rademacher W (1993) PGRs- present situation and outlook. Acta Hort 329:296–308

Stanca AM, Jenkins G, Hanson PR (1979) Varietal responses in spring barley to natural and artificial lodging and to a growth regulator. J Agric Sci (Camb) 93:449–456

Related Organisations

Content below is from across the PEP community and is not necessarily endorsed by Stewards or by PEP

Connected Content

Lodging

Lodging is the permanent displacement of plant stems from their vertical position and usually only occurs after flowering. It commonly occurs in many crop species including all cereals, oilseed rape, maize and sunflowers. Lodging can reduce yield by up to 80% and causes several knock-on effects including reduced crop quality, greater grain drying costs, and slower harvest. It is a problem that limits crop productivity in both developed and developing countries.

Arbuscular Mycorrhizal Fungi (AMF)

The attention placed on soil health in agriculture has been receiving more and more attention in recent years primarily due to our improved understanding of the interactions between soil health and overall crop performance in both arable and horticultural systems. This has led to increased soil monitoring and analysis as well as the adoption of alternative farming methods such as cover-cropping and min-till plowing to improve overall soil longevity. However, this increased adoption of more sustainable practices is heavily restricted to organic systems as conventional farming continues to be heavily reliant on high-input chemical fertilizers. Thus the presence of native Arbuscular Mycorrhizal Fungi, (AMF) has been steadily decreasing in soils for decades which has only increased our reliance on these high-input chemical systems, further locking us into a business-as-usual model going forwards. As yield loss from pest pressure and disease susceptibility continue to threaten global food security, costing an estimated $300 billion a year, the race to find the best long-term solutions that pragmatically improve whole system resilience to biotic and abiotic factors is in our midst. Could AMF be part of the solution going, forwards? Here is what we know so far and some recent breakthroughs in the science surrounding it.  

About text formats
Write whatever you want here - this is the main section. You can add links, add pictures and embed videos. To paste text from elsewhere use CTRL+Shift+V to paste without formatting. Add videos by selecting 'Full HTML' below, copying the 'embed html' from the source page (eg Youtube), clicking 'Source' above and pasting where you want the video to appear.
You can upload an image here. It can be jpg, jpeg, gif or png format.
Upload requirements
File

You can upload a file here, such as a pdf report, or MS Office documents, Excel spreadsheet or Powerpoint Slides.

Upload requirements
Authors Order
Add Authors here - you can only add them if they already exist on PEP. Just start writing their name then select to add it. To add multiple authors click the 'Add another item' button below.

Please ensure that you have proof-read your content. Pages are not edited further once submitted and will go live immediately.

Configure the meta tags below.

Use tokens to avoid redundant meta data and search engine penalization. For example, a 'keyword' value of "example" will be shown on all content using this configuration, whereas using the [node:field_keywords] automatically inserts the "keywords" values from the current entity (node, term, etc).

Browse available tokens.
Basic tags

Simple meta tags.

The text to display in the title bar of a visitor's web browser when they view this page. This meta tag may also be used as the title of the page when a visitor bookmarks or favorites this page, or as the page title in a search engine result. It is common to append '[site:name]' to the end of this, so the site's name is automatically added. It is recommended that the title is no greater than 55 - 65 characters long, including spaces.
A brief and concise summary of the page's content, preferably 150 characters or less. Where as the description meta tag may be used by search engines to display a snippet about the page in search results, the abstract tag may be used to archive a summary about the page. This meta tag is no longer supported by major search engines.
Advanced

Meta tags that might not be needed by many sites.

Geo-spatial information in 'latitude; longitude' format, e.g. '50.167958; -97.133185'; see Wikipedia for details.
Geo-spatial information in 'latitude, longitude' format, e.g. '50.167958, -97.133185'; see Wikipedia for details.
Robots
A comma-separated list of keywords about the page. This meta tag is used as an indicator in Google News.
Highlight standout journalism on the web, especially for breaking news; used as an indicator in Google News. Warning: Don't abuse it, to be used a maximum of 7 times per calendar week!
This meta tag communicates with Google. There are currently two directives supported: 'nositelinkssearchbox' to not to show the sitelinks search box, and 'notranslate' to ask Google not to offer a translation of the page. Both options may be added, just separate them with a comma. See meta tags that Google understands for further details.
Used to rate content for audience appropriateness. This tag has little known influence on search engine rankings, but can be used by browsers, browser extensions, and apps. The most common options are general, mature, restricted, 14 years, safe for kids. If you follow the RTA Documentation you should enter RTA-5042-1996-1400-1577-RTA
Indicate to search engines and other page scrapers whether or not links should be followed. See the W3C specifications for further details.
Sets a cookie on the visitor's browser. Can be in either NAME=VALUE format, or a more verbose format including the path and expiration date; see the link for full details on the syntax.
Tell search engines when to index the page again. Very few search engines support this tag, it is more useful to use an XML Sitemap file.
Control when the browser's internal cache of the current page should expire. The date must to be an RFC-1123-compliant date string that is represented in Greenwich Mean Time (GMT), e.g. 'Thu, 01 Sep 2016 00:12:56 GMT'. Set to '0' to stop the page being cached entirely.
Open Graph

The Open Graph meta tags are used to control how Facebook, Pinterest, LinkedIn and other social networking sites interpret the site's content.

The Facebook Sharing Debugger lets you preview how your content will look when it's shared to Facebook and debug any issues with your Open Graph tags.

The URL of an image which should represent the content. The image must be at least 200 x 200 pixels in size; 600 x 316 pixels is a recommended minimum size, and for best results use an image least 1200 x 630 pixels in size. Supports PNG, JPEG and GIF formats. Should not be used if og:image:url is used. Note: if multiple images are added many services (e.g. Facebook) will default to the largest image, not specifically the first one. Multiple values may be used, separated by a comma. Note: Tokens that return multiple values will be handled automatically. This will be able to extract the URL from an image field if the field is configured properly.
The URL of an video which should represent the content. For best results use a source that is at least 1200 x 630 pixels in size, but at least 600 x 316 pixels is a recommended minimum. Object types supported include video.episode, video.movie, video.other, and video.tv_show. Multiple values may be used, separated by a comma. Note: Tokens that return multiple values will be handled automatically.
A alternative version of og:image and has exactly the same requirements; only one needs to be used. Multiple values may be used, separated by a comma. Note: Tokens that return multiple values will be handled automatically. This will be able to extract the URL from an image field if the field is configured properly.
The secure URL (HTTPS) of an image which should represent the content. The image must be at least 200 x 200 pixels in size; 600 x 316 pixels is a recommended minimum size, and for best results use an image least 1200 x 630 pixels in size. Supports PNG, JPEG and GIF formats. Multiple values may be used, separated by a comma. Note: Tokens that return multiple values will be handled automatically. This will be able to extract the URL from an image field if the field is configured properly. Any URLs which start with "http://" will be converted to "https://".
The type of image referenced above. Should be either 'image/gif' for a GIF image, 'image/jpeg' for a JPG/JPEG image, or 'image/png' for a PNG image. Note: there should be one value for each image, and having more than there are images may cause problems.
The date this content was last modified, with an optional time value. Needs to be in ISO 8601 format. Can be the same as the 'Article modification date' tag.
Links an article to an author's Facebook profile, should be either URLs to the author's profile page or their Facebook profile IDs. Multiple values may be used, separated by a comma. Note: Tokens that return multiple values will be handled automatically.
The date this content was published on, with an optional time value. Needs to be in ISO 8601 format.
The date this content was last modified, with an optional time value. Needs to be in ISO 8601 format.
The date this content will expire, with an optional time value. Needs to be in ISO 8601 format.
Twitter Cards

A set of meta tags specially for controlling the summaries displayed when content is shared on Twitter.

Notes:
  • no other fields are required for a Summary card
  • Photo card requires the 'image' field
  • Media player card requires the 'title', 'description', 'media player URL', 'media player width', 'media player height' and 'image' fields,
  • Summary Card with Large Image card requires the 'Summary' field and the 'image' field,
  • Gallery Card requires all the 'Gallery Image' fields,
  • App Card requires the 'iPhone app ID' field, the 'iPad app ID' field and the 'Google Play app ID' field,
  • Product Card requires the 'description' field, the 'image' field, the 'Label 1' field, the 'Data 1' field, the 'Label 2' field and the 'Data 2' field.
A description that concisely summarizes the content of the page, as appropriate for presentation within a Tweet. Do not re-use the title text as the description, or use this field to describe the general services provided by the website. The string will be truncated, by Twitter, at the word to 200 characters.
By default Twitter tracks visitors when a tweet is embedded on a page using the official APIs. Setting this to 'on' will stop Twitter from tracking visitors.
The URL to a unique image representing the content of the page. Do not use a generic image such as your website logo, author photo, or other image that spans multiple pages. Images larger than 120x120px will be resized and cropped square based on longest dimension. Images smaller than 60x60px will not be shown. If the 'type' is set to Photo then the image must be at least 280x150px. This will be able to extract the URL from an image field if the field is configured properly.
The MIME type for the media contained in the stream URL, as defined by RFC 4337.

Members

Pete Berry