http://modernfarmer.com/2014/04/microbes-will-feed-world-real-farmers-grow-soil-crops/
Out on the horizon of agriculture’s
future, an army 40,000 strong is marching towards a shimmering goal.
They see the potential for a global food system where pesticides,
herbicides and fertilizers are but relics of a faded age.
They are not farmers, but they are
working in the name of farmers everywhere. Under their white lab coats
their hearts beat with a mission to unlock the secrets of the soil —
making the work of farmers a little lighter, increasing the productivity
of every field and reducing the costly inputs that stretch farmers’
profits as thin as a wire.
‘Producing
more food with fewer resources may seem too good to be true, but the
world’s farmers have trillions of potential partners that can help
achieve that ambitious goal. Those partners are microbes.’
The American Society of Microbiologists (ASM) recently released a treasure trove of their latest
research and
is eager to get it into the hands of farmers. Acknowledging that
farmers will need to produce 70 to 100 percent more food to feed the
projected 9 billion humans that will inhabit the earth by 2050, they
remain refreshingly optimistic in their work. The introduction to their
latest report states:
“Producing more food with fewer resources may seem too good to be
true, but the world’s farmers have trillions of potential partners that
can help achieve that ambitious goal. Those partners are microbes.”
Mingling with Microbes
Linda Kinkel of the University of Minnesota’s Department of Plant
Pathology was one of the delegates at ASM’s colloquium in December 2012,
where innovators from science, agribusiness and the USDA spent two days
sharing their research and discussing solutions to the most pressing
problems in agriculture.
“We understand only a fraction of what microbes do to aid in plant
growth,” she says. “But the technical capacity to categorize the vast
unknown community [of microorganisms] has improved rapidly in the last
couple of years.”
Microbiologists have thoroughly documented instances where
bacteria,
fungi,
nematodes — even viruses — have formed mutually beneficial associations
with food plants, improving their ability to absorb nutrients and
resist drought, disease and pests. Microbes can enable plants to better
tolerate extreme temperature fluctuations, saline soils and other
challenges of a changing climate. There is even evidence that microbes
contribute to the finely-tuned flavors of top-quality produce, a
phenomenon observed in strawberries in particular.
“But we’re only at the tip of the iceberg,” says Kinkel.
In the Field
Statements such as, “There are 10 to the 6th fungal organisms in a gram of soil!” and, “This bacterial
biofilm
has tremendous communication properties!” are breakroom banter among
microbiologists, but what does it all mean for farmers? The answers
reach back into the millennial past of agriculture, back to the dawn of
life on earth.
Whenever a seed germinates in the wild or a crop is planted by a
farmer, the microbial community that helps that species to grow and
thrive is mobilized. Chemical signals enter the soil via the exudates of
the plant and a symphony of underground activity commences. Genetic
information is exchanged; the various microbial players assume their
positions on the tissues of the plant; often, one microbe colonizes
another, providing a service that helps the first microbe to assist the
plant whose roots it is embedded in.
Though this elaborate dance takes place without any input from humans, we have been tinkering with it for a long time.
For example, the process of
nitrogen fixation
in plants of the legume family (which includes beans, peas, peanuts and
many other crop plants) is one of the little bacterial miracles that
makes our planet habitable. Anyone who has ever observed the roots of a
legume knows that they are covered in strange white or pinkish growths,
about the size of ants, which appear to be an infection of some sort.
Undoubtedly, ancient farmers had an intuitive understanding that these
warty protuberances had something to do with the noticeable ability of
legumes to improve the soil, but it wasn’t until the late 19th century
that the mystery began to unfold.
While Louis Pasteur was discovering how to preserve milk and becoming
famous as the father of microbiology, a relatively unknown colleague of
his with a penchant for plants was making another discovery, of perhaps
even greater historical importance. In 1888,
Martinus Beijerinck,
discovered that tiny bacteria called Rhizobia infect the roots of
legumes, causing the swollen nodules. Rather than an infection that
weakens the plant, the nodules are the fertilizer factories of the plant
kingdom, disassembling atmospheric nitrogen — which plants are unable
to use — and refashioning it in a soluble, plant-friendly form.
Rhizobia are key ingredients of the earth’s verdancy and harnessing
the bacteria to improve soil fertility has long been one of the
cornerstones of sustainable agriculture. Yet, modern day microbiologists
are now aware of scores of other equally profound plant-microbe
interactions, discoveries they believe will have a big impact as human
populations continue to soar on a planet of finite resources.
Making the Translation
In her lab at the university, Kinkel experiments with antibiotic
bacteria that suppress plant pathogens and tests various soil management
strategies to see their effects on microbial communities. In Colombia,
microbiologists have learned to propagate a fungus that colonizes
cassava plants and increases yields up to 20 percent. Its
hyphae —
the tiny tentacles of fungi — extend far beyond the roots of the
cassava to unlock phosphorus, nitrogen and sulfur in the soil and siphon
it back to their host, like an IV of liquid fertilizer.
In
Colombia, microbiologists have learned to propagate a fungus that
colonizes cassava plants and increases yields up to 20 percent
Though microbiologists can coerce soil to produce extraordinary plant
growth in their labs and test plots, transferring the results to
everyday agricultural practices is not a straightforward process.
“Connections to farmers are a weak link,” Kinkel laments, alluding to
a “snake oil effect” where farmers have become leery of salesmen
hawking microbial growth enhancers that don’t pan out in the field. “The
challenge of [these] inoculants,” she says, “is they may not translate
in all environments.”
Though researchers continue to develop promising new microbial
cocktails, there is an increased focus on guiding farmers to better
steward the populations that already exist in their soil. Kinkel is
working on an approach she believes will help farmers sustain optimal
microbial communities by ensuring they have the food they need — carbon —
at all times. She calls it ‘slow release carbon’, but it’s not
something farmers will see in supply catalogs anytime soon. Kinkel says
she has access to resources for her academic research, but lacks a
“deliberate pipeline for product development.”
It Takes a Global Village
The 26 experts from around the world convened at the ASM colloquium
concluded their discussions with a bold goal for the future of
agriculture: They’ve challenged themselves to bring about a 20 percent
increase in global food production and a 20 percent decrease in
fertilizer and pesticide use over the next 20 years.
With an indomitable belief that science will do its part to make this
dream a reality, the scientists are looking to their corporate and
regulatory counterparts to build a pipeline of information to farmers.
They’re hoping that top-down investments in research and technology will
meet directly with grassroots changes in the culture of farming —
without all the snake oil-vending agribusiness interests in the middle.
Ultimately, they envision a future where farmers again trust in the
unseen forces of the soil — instead of the fertilizer shed — for answers
to their challenges.
Een wormenbak is een ideale methode om keukenafval te recyclen tot een rijke donkere, naar bosgrond ruikende grond of bodemverbeteraar. Het grote voordeel van wormencompost is dat men hem zowel binnen- als buitenshuis kan maken. Zo kunnen ook mensen die op een appartement wonen hun groente- en fruitafval composteren.