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This is nothing new because for example Masanobu Fukuoka has not only suggested this long time ago but also made succesful experiments in the Northern Africa.
Sorry for my broken English.
HOWDY
NOVEMBER 25, 2019
by Massachusetts Institute of Technology
https://phys.org/news/2019-11-coated-seeds-enable-agriculture-marginal.html
Providing seeds with a protective coating that also supplies essential nutrients to the germinating plant could make it possible to grow crops in otherwise unproductive soils, according to new research at MIT.
A team of engineers has coated seeds with silk that has been treated with a kind of bacteria that naturally produce a nitrogen fertilizer, to help the germinating plants develop. Tests have shown that these seeds can grow successfully in soils that are too salty to allow untreated seeds to develop normally. The researchers hope this process, which can be applied inexpensively and without the need for specialized equipment, could open up areas of land to farming that are now considered unsuitable for agriculture.
The findings are being published this week in the journal PNAS, in a paper by graduate students Augustine Zvinavashe ’16 and Hui Sun, postdoc Eugen Lim, and professor of civil and environmental engineering Benedetto Marelli.
The work grew out of Marelli’s previous research on using silk coatings as a way to extend the shelf life of seeds used as food crops. “When I was doing some research on that, I stumbled on biofertilizers that can be used to increase the amount of nutrients in the soil,” he says. These fertilizers use microbes that live symbiotically with certain plants and convert nitrogen from the air into a form that can be readily taken up by the plants.
Not only does this provide a natural fertilizer to the plant crops, but it avoids problems associated with other fertilizing approaches, he says: “One of the big problems with nitrogen fertilizers is they have a big environmental impact, because they are very energetically demanding to produce.” These artificial fertilizers may also have a negative impact on soil quality, according to Marelli.
Although these nitrogen-fixing bacteria occur naturally in soils around the world, with different local varieties found in different regions, they are very hard to preserve outside of their natural soil environment. But silk can preserve biological material, so Marelli and his team decided to try it out on these nitrogen-fixing bacteria, known as rhizobacteria.
“We came up with the idea to use them in our seed coating, and once the seed was in the soil, they would resuscitate,” he says. Preliminary tests did not turn out well, however; the bacteria weren’t preserved as well as expected.
That’s when Zvinavashe came up with the idea of adding a particular nutrient to the mix, a kind of sugar known as trehalose, which some organisms use to survive under low-water conditions. The silk, bacteria, and trehalose were all suspended in water, and the researchers simply soaked the seeds in the solution for a few seconds to produce an even coating. Then the seeds were tested at both MIT and a research facility operated by the Mohammed VI Polytechnic University in Ben Guerir, Morocco. “It showed the technique works very well,” Zvinavashe says.
The resulting plants, helped by ongoing fertilizer production by the bacteria, developed in better health than those from untreated seeds and grew successfully in soil from fields that are presently not productive for agriculture, Marelli says.
In practice, such coatings could be applied to the seeds by either dipping or spray coating, the researchers say. Either process can be done at ordinary ambient temperature and pressure. “The process is fast, easy, and it might be scalable” to allow for larger farms and unskilled growers to make use of it, Zvinavashe says. “The seeds can be simply dip-coated for a few seconds,” producing a coating that is just a few micrometers thick.
The ordinary silk they use “is water soluble, so as soon as it’s exposed to the soil, the bacteria are released,” Marelli says. But the coating nevertheless provides enough protection and nutrients to allow the seeds to germinate in soil with a salinity level that would ordinarily prevent their normal growth. “We do see plants that grow in soil where otherwise nothing grows,” he says.
These rhizobacteria normally provide fertilizer to legume crops such as common beans and chickpeas, and those have been the focus of the research so far, but it may be possible to adapt them to work with other kinds of crops as well, and that is part of the team’s ongoing research. “There is a big push to extend the use of rhizobacteria to nonlegume crops,” he says. One way to accomplish that might be to modify the DNA of the bacteria, plants, or both, he says, but that may not be necessary.
“Our approach is almost agnostic to the kind of plant and bacteria,” he says, and it may be feasible “to stabilize, encapsulate and deliver [the bacteria] to the soil, so it becomes more benign for germination” of other kinds of plants as well.
Even if limited to legume crops, the method could still make a significant difference to regions with large areas of saline soil. “Based on the excitement we saw with our collaboration in Morocco,” Marelli says, “this could be very impactful.”
As a next step, the researchers are working on developing new coatings that could not only protect seeds from saline soil, but also make them more resistant to drought, using coatings that absorb water from the soil. Meanwhile, next year they will begin test plantings out in open experimental fields in Morocco; their previous plantings have been done indoors under more controlled conditions.
More information: Augustine T. Zvinavashe el al., “A Bioinspired Approach to Engineer Seed Microenvironment to Boost Germination and Mitigate Soil Salinity,” PNAS (2019). www.pnas.org/cgi/doi/10.1073/pnas.1915902116
Journal information: Proceedings of the National Academy of Sciences
Provided by Massachusetts Institute of Technology
How gardeners are reclaiming agriculture from industry, one seed at a time
DECEMBER 18, 2019
by Helen Anne Curry, The Conversation
https://phys.org/news/2019-12-gardeners-reclaiming-agriculture-industry-seed.html
Agriculture has changed significantly in the past century. Bigger machines, bigger farms and bigger budgets allow fewer farmers to produce more food. Changes in science and policy have also resulted in an industry in which power over what we grow and eat is increasingly held by very few.
Consider one of agriculture’s most basic inputs: the seed. Although there have long been farmers and merchants who specialised in growing and selling seeds, it wasn’t until the 20th century that people started talking about seed production as an industrial process. Thanks to changes in farming, science and government regulations, most of the “elite” seed that is bought and sold around the world today is mass produced and mass marketed—by just four transnational corporations.
This transition has made many people uneasy. As a result, a new movement is growing, one that aims to wrest power back through the renewal of an age-old agricultural task: setting aside some seeds from each season’s harvest to plant in the next. Community gardeners, home growers and small-scale farmers increasingly insist that seeds should be something they produce themselves, or get from a friend or neighbour, rather than something they buy off the shelf.
For some, seed saving is a way of keeping history alive, for example by growing the vegetables their grandparents enjoyed. For others, it’s a way to save money, or to connect with their community. And today, it is increasingly a political statement—a choice that allows consumers to avoid fruits, vegetables and other foods produced at an industrial scale. Depending on the grower, it may even be all of these—and more.
Many seed savers are motivated by the idea that their actions contribute to keeping diverse crop varieties from disappearing, especially those ignored by industrial farms or commercial seed companies in their pursuit of profit. Organisations such as the Heritage Seed Library (UK) and the Seed Savers Exchange (US), and the growers they represent, routinely connect the individual acts of growing, storing and sharing seed with a global conservation mission. In cultivating awareness of this connection, they have transformed a timeless task into a powerful political act.
So how exactly did this transformation occur? New historical research shows that concerned citizens and organisations worked hard to make it happen.
The Heritage Seed Library, today a part of the British non-profit Garden Organic, offers a case in point. This collection of 800 or so local and rare vegetable varieties has its roots in a campaign to save endangered vegetables that Garden Organic launched in the 1970s, back when it was known as the Henry Doubleday Research Association, or HDRA.
At the time, the HDRA was well established as source of expert advice on organic gardening in Britain. Its director Lawrence Hills had founded the organisation in 1954 to encourage gardeners to experiment with natural pest deterrents, green manures and other alternatives to the synthetic chemicals that were becoming common in agriculture.
Among the many subjects on which the HDRA offered advice from its earliest days was helping “own growers”—backyard gardeners, allotment holders, and others growing food to eat themselves—to decide what varieties to plant. Hills was adamant that newer types of tomatoes, carrots and green beans lacked the flavours of earlier generations and performed worse in small-scale cultivation.
He was therefore dismayed to learn in the early 1970s that changes in British agricultural regulations would make it difficult for seed companies to sell “old-fashioned varieties”. He feared, rightly, that the small market for such seeds would not justify the price that a company would now have to pay to register these for legal sale. If seed companies weren’t stocking them—and growers accustomed to buying their seed weren’t saving them—these old-fashioned varieties would simply disappear.
In a 1975 letter to the Times, Hills announced an initiative of the HDRA intended to address this impending extinction crisis: establishing a collection of Europe’s “vanishing vegetables” at the HDRA.
Hills asked fellow gardeners to help him locate as many uncommon varieties as possible. Ambitious as it was, that collection was only the start.
The HDRA soon began a campaign to start a “seed bank”. Hills envisioned that this long-term storage facility would gather and preserve vegetable varieties from around the world. In this sense, it would be just like a few already existing international seed banks, which ensured that diverse seeds would be available for plant breeders in the future. Unlike those seed banks (also called “genebanks”), the vegetable collection that Hills imagined would have a public-facing component, a “seed library” that any grower, regardless of professional expertise, would be able to access.
Both seed bank and seed library eventually came to fruition, though not in a single institution. When it became apparent during planning that a government-supported Vegetable Gene Bank would mainly serve professional researchers, Hills and HDRA staff organised The Heritage Vegetable Seed Library for Research and Experiment—later shortened to the Heritage Seed Library—to serve the needs of ordinary gardeners. Launched in February 1978, the library gave away seed of its rare varieties to subscribing members.
The Heritage Seed Library was the more innovative of the two projects, and arguably the more transformative of British vegetable conservation in the long term. This was because it emphasised the need for the active participation of individual gardeners to to achieve conservation goals. The library only functioned with the help of “seed guardians” who helped keep it stocked with seed. HDRA also encouraged library users to learn how to save their own seed.
Together with other HDRA initiatives, the seed library helped cement the idea that conservation of vegetable diversity would only succeed through the commitment of ordinary gardeners to purchasing, growing, saving and circulating seeds of useful or delicious varieties.
Today, many home and allotment garderners who save seeds see themselves as protectors of endangered plants—and their gardens as repositories of important biodiversity. They believe that their stewardship of vegetable diversity contributes to the possibilities for a better, fairer global food system in the future. The history of the HDRA reminds us that there was—and still is—work involved in connecting these individual acts of seed saving to the future of the world’s food.
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