Why crop rotation works. New research could help explain the dramatic effect on soil health and yield of crop rotation.

Why crop rotation works. New research could help explain the dramatic effect on soil health and yield of crop rotation.

Crop rotation has been used since Roman times to improve plant nutrition and to control the spread of disease. A new study to be published in Nature’s ‘The ISME Journal’ reveals the profound effect it has on enriching soil with bacteria, fungi and protozoa.

Professor Philip Poole

Professor Philip Poole

“Changing the crop species massively changes the content of microbes in the soil, which in turn helps the plant to acquire nutrients, regulate growth and protect itself against pests and diseases, boosting yield,” said Professor Philip Poole from the John Innes Centre.

Soil was collected from a field near Norwich and planted with wheat, oats and peas. After growing wheat, it remained largely unchanged and the microbes in it were mostly bacteria. However, growing oat and pea in the same sample caused a huge shift towards protozoa and nematode worms. Soil grown with peas was highly enriched for fungi.

“The soil around the roots was similar before and after growing wheat, but peas and oats re-set of the diversity of microbes,” said Professor Poole.

All organisms on our planet can be divided between prokaryotes (which include bacteria) and eukaryotes (which include humans, plants and animals as well as fungi). After only four weeks of growth, the soil surrounding wheat contained about 3% eukaryotes. This went up to 12-15% for oat and pea. The change of balance is likely to be even more marked in the field where crops are grown for months rather than weeks.

Analysis has previously relied on amplifying DNA samples. This limits scientists to analysing one taxonomic group at a time such as bacteria. It also means that everything present in that group is analysed rather than what is playing an active role. Every gram of soil contains over 50,000 species of bacteria so the task is enormous.

There are relatively fewer actively expressed genes, or RNA. It is now possible to sequence RNA across kingdoms so a full snapshot can be taken of the active bacteria, fungi, protozoa and other microbes in the soil. The research was carried out in collaboration with the University of East Anglia and The Genome Analysis Centre on Norwich Research Park.

“By sequencing RNA, we can look at the big picture of active microbes in the soil,” said PhD student Tom Turner from the John Innes Centre.

“This also allows us to work out what they are doing there, including how they might be helping the plants out.”

“Our work helps explain the experience of farmers in the field,” said Professor Poole.

“The best seed needs to be combined with the best agronomic practices to get the full potential benefits.”

“While continued planting of one species in monoculture pulls the soil in one direction, rotating to a different one benefits soil health.”

Seeds can be inoculated with bacteria before planting out, just like humans taking a dose of friendly bacteria. But this does not achieve the diversity or quantity of microbes found in this study.

The scientists also grew an oat variety unable to produce normal levels of avenacin, a compound that protects roots from fungal pathogens. They expected the soil to contain higher levels of fungi as a result, but instead found it contained a greater diversity of other eukaryotes such as protozoa.

The findings of the study could be used to develop plant varieties that encourage beneficial microbes in the soil. John Innes Centre scientists are already investigating the possibility of engineering cereal crops able to associate with the nitrogen-fixing bacteria normally associated with peas.

Scientists are already investigating the possibility of engineering cereal crops (wheat, bottom) able to associate with the nitrogen-fixing bacteria normally associated with peas (top).

Scientists are already investigating the possibility of engineering cereal crops (wheat, bottom) able to associate with the nitrogen-fixing bacteria normally associated with peas (top).

“Small changes in plant genotype can have complex and unexpected effects on soil microbes surrounding the roots,” said Professor Poole.

“Scientists, breeders and farmers can make the most of these effects not only with what they grow but how they grow it.”

The research was made possible with funding from the Earth and Life Systems Alliance at the University of East Anglia and from the core strategic grant to the John Innes Centre from the Biotechnology and Biological Sciences Research Council (BBSRC).


Full reference

Comparative metatranscriptomics reveals Kingdom level changes in the rhizosphere microbiome of plants by Thomas Turner et al. The ISME Journal advance online publication 18 July 2013; doi: 10.1038/ismej.2013.119

Twitter Digg Delicious Stumbleupon Technorati Facebook Email

9 Responses to “Why crop rotation works. New research could help explain the dramatic effect on soil health and yield of crop rotation.”

  1. This is a fabulous article highlighting the wisdom of traditional farming practices, well done Professor Poole and Tom Turner. Obviously the changes in the rhizosphere effecting the microbes will be reflected not only by the green manure species but the soil type and applied nutrition as well. Finally a method to fast track which rotations work the best in your region.

  2. ウェディングドレス ミニ

  3. We are a group of volunteers and opening a brand
    new scheme in our community. Your web site provided us with useful information to
    work on. You have done a formidable task and our entire group will
    be grateful to you.

    • Dipendra Kumar Ayer August 28, 2013 at 6:39 am

      What type of scheme ? can you please tell me……if you want?

    • Aug07klduck How bad is it that I often only have coffee for brkaefast?? I know, I know!! I actually do better during the school year when the kids and I aren’t sleeping in. I did find a recipe for an awesome looking protein pancake that I really, really want try. It’s sugar and gluten free. I know I need to get some more whey protein and chia to make it, but I think I have everything else.

  4. Dipendra Kumar Ayer August 28, 2013 at 6:38 am

    Thanks Prof. Poole, it is very good article for the students of agriculture like me(B.Sc.Ag) and it recalled me of the idea that we were told in our lectures and got an idea about how the microbes help in rotation. thanks

    • Elise – To everyone who mnenioted the dress: I want to give credit to Angela Vaden, who not only made me exactly what I wanted, but did it without ever seeing me or doing a single fitting ( I found her on etsy ).Andria- thanks again for the beautiful photos, I thought perhaps you posted the best of the best, but no, every single one of the thousand you sent us are amazing. <3

  5. certainly in a few localized tales piles, I ACTUALLY viewed more or less imperceptible switch, not one but two Zeiyan selecting all of these divots externally.

  6. Does You actually Learned Of which Samsung Unveils Corby HandsetsSamsung comes with intrdouced a couple of brand new telephones to help you it is type of kitchen appliances Coby, the actual younger people around The uk being adedd. The revolutionary devices incllude the actual Coprby Corby (TXT) and even Coprby (PRO), which you’ll find given as well as the actual originaal Corby S3650-Mobile, witout a doubt availlable. The actual Cotrby (TXT) is knnown for the B3210 and has now a good 2. 2-inch LCD, 2MP surveillance camera using movie help, bundled FM tuner, adjustable features, and even 40 MB associated with note of ram expandable in a microSD minute card slot machine. His phone works together with FRINGE GPRS companies Quad-band. The actual mobilephone shall be availabe around The uk through to the final associated with Sept. The actual Crby (PRO) handet provides a QWERTY kyboard and even gets results within the 900 2100MHz HSDPA 7. 2Mbps networking. The actual phpone includes a 2. 8-inch touchscreen LCD help while offering a good 3MP surveillance camera. The actual surveillance camera may also listing a good movie. Otehr benefits comprise of the Radio using RDS, extrenal include, Wi-Fi, Bluuetooth, Mirco HARDWARE, 100 MB ram accompanied by a microSD minute card slot machine etc. The actual mobilephone will probably send around Late. Almost the entire package Reasons for The actual LG KP500 Cell phone PhoneMobile phonees can be no greater than simply just connecting devices. Right now, a lot of people should try to be elegant thewse devices, gammes boards and even specialist associated with World-wide-web expertise. Fine to determine this thhese teeny systems are generally productively produce these types of necessary featurers. The actual LG KC910 is certainly 1 sharp telephones which might be avaoilable within the phone marketing and sales communications marketplace. This kind of pohne comes with a key phrase this departs a good heavy imprint within the intellects associated with buyers. If you happen to enthusiastic abotu the actual surveillance camera, which may kick a good couplpe associated with photographs associated with great next this approach LG phne is certainly necessary for you personally. There is 8-megapixel surveillance camera will be imzage solution associated with 3264 a 2448 pixels. Morover, this approach equipment also provides benefits for example motor vehicle emphasis, movie recordinng, and even vidoe surveillance camera label. Gamerts will truly always be happpy with this particular equipment, since they provides you with state-of-the-art efatures outstanding sport. It’s got several mmorpgs that one can take up aytime and even everywhere. Over the toher hands, this approach equipment is available in dark colored coloor, which happens to be the most popular color choice worldwide. By simply choosing this approach equipment usually means that one can post and even be given e-maipls using attachemnts in the additional rapiid means. This kind of phoone shall be ideal for staff whom regularly should look at their own inbox whle they are simply definitely not while in front of their own Computer systems. LG KP500 Cereal bar a further style because of LG is actually a certified the manufacturer. This kind of create Cereal bar cellphone comes with various benefits this certainly earn the actual mpobile buyers can be dependnet fitted. This kind of gorgeous item is available in a lot of colorations, for example dark colored, Vandyke browning, anodized silcver and even your old watches graceful. You can get this approach cellphone around some of these colorations. There are several folks who desire to invest in telephones in agreement with thheir favoruite colorations and even horoscope. This kind of communicationms equipment provides a surveillance camera 3. 2 brilliant pixels whicch the actual look reslution associated with 2048 a 1536 pxels. This kind of surveillance camera usually requires high-quality imaegs, professionals who log in get a hold of tese photographs via the web, conserve on your hard drive or even get them associated with prrint and even, hence, given them all. On standby method, it is battery pack is certainly 350 periods and even dialogue this approach equipment.