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September 11, 2009
· Potato blight mysteries unveiled by UK scientists
· Drought forcing Aussies to adopt dryland practices
· Cover crops can help optimize organic production
· Organic certification is almost all in the paperwork
· Forget the gardener, Toronto goes for urban farmers
Potato blight mysteries unveiled by UK
(FT.com) – Scientists have discovered the genetic reason for the adaptability and virulence of the potato blight organism, which caused the Irish famine of the 1840s and is responsible for an estimated £4bn ($6.6bn) a year of crop losses worldwide.
A large international research team announced the decoding
of the genome of the pathogen, Phytophthora infestans, on Wednesday at the British Science Festival in
Guildford,
The genome is big for a micro-organism and has an extraordinary structure that enables it to follow a “two-speed” strategy to outwit its plant hosts.
One part contains conventional genes and evolves slowly. The other, larger part contains many repeated stretches of DNA together with genes involved in plant infection, which can mutate swiftly.
“This two-speed genome structure might enable P. infestans to adapt rapidly to host plants while the core set of genes for the basic biology of the organism remain conserved,” said Sophien Kamoun, a study lead author and head of the Sainsbury Laboratory in Norwich. “Something similar has been observed in other pathogens but this is the most extreme case.”
P. infestans looks like a microscopic fungus but is known to be a variety of water mold. These are more closely related to the malaria parasite than true fungi.
Scientists had been puzzled by the speed with which it
adapts to new plant hosts, including potatoes painstakingly bred to fend off
infection. Blight has re-emerged as a pervasive threat to potatoes – the
world’s most important non-cereal crop – and tomatoes worldwide. A damaging new
strain called Blue 13 is present in potato fields in the British Isles and
northern
“We now have a comprehensive view of the P. infestans genome, revealing the unusual properties that
drive its remarkable adaptability,” said Chad Nusbaum,
of the Broad Institute in
Plant scientists expect to complete the genomes of the
tomato and potato next year. Then they will be able to match up the strengths
and weaknesses of the pathogen and its hosts, in the quest for treatments for
blight. “The genomes will give us an idea of the plants’ immune system and how
they respond to infection,” said Paul Birch, of the
But Prof Kamoun warned that science was unlikely to eliminate the threat of blight. “As plant pathologists we know you should never bet against the pathogen,” he said.
Drought forcing Aussies to adopt dryland practices
(theage.com.au) – IF AUSTRALIA'S severe dry spell has an upside, it is the number of engineering companies that have emerged with better ways to help people manage water.
Black & Veatch, a big US group with expertise in urban
water systems, set up in
Regional communities, particularly those in the
Mr Fagan is leader of
sustainability in the Asia Pacific for MWH, a company based in
In the Murray-Darling, MWH sees the future in various aspects of forestry, using native species, mainly different forms of Mallee eucalypt, for carbon-negative biomass, and even carbon sinks.
Mr Fagan's vision is to plant native vegetation - the Mallee eucalypt - in wind rows that still allow traditional farming, and eventually create a chain of 50 smaller biomass power stations that could be easily integrated into the electricity grid.
Farmers could also look at other product streams, such as eucalyptus oil, from the trees. ''You can take the oil out and still use the wood for biomass,'' he said.
Mr Fagan, who worked on the Murrumbidgee irrigation project with the late Dick Pratt,
said
Niche markets with a better grade oil were possible, such as pharmaceutical grade eucalyptus oil. Eucalyptus oil was also used as an industrial solvent for ethanol-based fuels.
Mr Fagan said to produce eucalyptus oil on its own in the face of cheap, price competition was not feasible. ''You'll get done,'' he said. But combined with energy production, and even agrichar when it was burnt, it could create five or six income streams. ''This changes the economics of the industry. You can select the Mallee species for oil or biomass or a combination of both.''
Mr Fagan said the idea was not to plant large blocks of trees, which could have an impact on water run-off. Trees created windbreaks and shade, and helped the soil retain moisture. But establishment costs were high, so there was a need for scale, he said.
John Williams, adjunct professor of agriculture and natural
resources at
The mallee trees coppiced very
well, said Professor Williams, who is also a former chief of
They could produce a variety of products ranging from oil to charcoal and solvents that could be used in paints. ''They are also more sustainable from a water use perspective,'' he said.
Cover crops can help optimize organic production
(cfbf.com) – Using cover crops to improve soil and manage pests has become an integral part of many organic farming systems, especially with the cost of approved organic fertilizers and other materials suitable for organic production agriculture.
Long-term success in organic agriculture requires optimizing
the natural processes on the farm, including using cover crops, said Mark Van
Horn, director of the Student Farm at the Agricultural Sustainability Institute
at the
"If you rely mainly on products, then the success of your organic program would be short-lived," he said.
Cover crops can offer a number of benefits. They can provide nitrogen, increase soil organic matter and improve nutrient availability by increasing soil biological activity, he noted.
They can also improve soil tilth and structure, prevent soil erosion and increase the rate of water infiltration and availability. Many cover crops effectively suppress weeds and provide mulch to conserve soil moisture. They may also be used to provide habitat and food sources for beneficial insects while reducing other soil-borne pests.
"But cover crops don't come free," he said.
Cost of seed, energy and labor to plant cover crops may make them less attractive to some farmers. Another potential disincentive is water use, especially for farms that are struggling with current water shortages.
Van Horn warned that if cover crops are not managed effectively, they could actually increase weed problems, insects and pathogens in the soil. Cover crops that decompose slowly may also initially tie up nutrients needed by the cash crop. Another challenge of using a cover crop is finding a window of time when a cash crop is not being grown.
Choosing the right cover crop is critical, Van Horn said. Before growing a cover crop, he advises farmers to ask why they're growing it, what to grow, when to grow it and how it will be managed.
Organic certification is all in the paperwork
(burlingtonfreepress.com) -- Behind the lettuce, beans and zucchini that sit in bins at Amanda Gervais’s farmstand was a lot of planning and paperwork.
Before the heads of broccoli and Swiss chard ever emerged from the ground, Gervais had to document their origin, feed and caring. She has maps that prove she rotated the crops from the previous year, lists that tell what kind of seeds they started from, invoices that show how much organic fertilizer she used.
Record-keeping is a big part of life for a certified-organic farmer.
Some 540 farms in
The number of organic farmers in
“If I’m going to grow something, I wouldn’t spray pesticides and herbicides,” she said, noting her crops surround the North Hero home where she, her husband and two young children live.
Still, Gervais’ farm is certified organic for vegetables but not for the eggs her chickens produce or the pigs she raises. That, she said, would be cost-prohibitive for her farm’s size, so she settles for following many organic practices without the seal of certification.
Why certification?
North Hero resident Barbara Purinton
stopped at Gervais’
Purinton said she’s become more attentive about where her food comes from and how it’s grown.
“I’m more aware of what I’m putting into my body,” she said, adding, “It tastes better.”
Without certification, which Gervais has had since 2007, she could not sell her vegetables as organic. At a farmstand on her own property, where she can meet customers one-on-one, that’s not necessarily a big deal, but to sell to wholesalers she needs certification.
That requirement is what keeps Shoreham vegetable farmer Will Stevens going back every year to renew his organic certification, but it’s not what drove him to become certified more than two decades ago, he said. Instead, he joined the world of organic farming in 1987 to learn better farming techniques.
The network of information to which it connected him was invaluable, he said. The process he had to go through taught Stevens how to plan ahead for two years, how to fertilize his land and, perhaps most important, how to keep meticulous records.
“It made us better growers,” Stevens said. “That we had to keep records was a good thing.”
Those records proved important in a surprising way. In 1997, a neighboring farmer sprayed herbicides, and, because of faulty equipment, the chemicals strayed onto Stevens’ crops. With the records he kept, he was able to prove the size of his loss. “That helped us with the insurance claim,” Stevens said.
Forget the gardener, Toronto
(thestar.com) – Go to the backyard, pick, eat – it's the ultimate in local food.
The Young Urban Farmers, a trio of business school grads,
are on top of the trend. They set up and tend vegetable gardens in
"We're like a fast-track method," says Chris Wong, 23, a co-founder of the new company with the motto: "Fresh food from your backyard without the work."
Once upon a time, vegetable gardens seemed to be the preserves of immigrants and frugal folks. Now, even the time-challenged and well-to-do can have their own vegetable gardens without the pain of planting, pruning, getting their hands dirty or exercising any black thumbs.
"Some of them (clients) like to do the harvests themselves, and if friends or family are there, they can show off a little bit," Wong adds.
We are on a leafy crescent uptown. Despite all the landscapers, contractors, pool maintenance men and dog walkers, there's that peaceful hush in the neighbourhood.
"I guess you could call it atypical in terms of career paths that many of our classmates took," Wong muses about his growing business as he examines runner beans, assesses the ripeness of a bell pepper, clips herb sprigs and plucks tomatoes.
He replaces the wire net "critter guard" around a vegetable patch before delivering a handful of tomatoes and herbs, along with a handwritten progress report, to Shari Wilson, who comes to the patio.
At another stop nearby, Wong brushes through foliage to get at a bumper crop of cherry tomatoes, and talks about setting up a kids' program with a plant diary that would incorporate reading, writing and math. The idea was inspired by 3-year-old Sasha Cumming. She is always keen to help with the picking – and eating.
Mom Sofia Cumming looks on, with baby Dylan, 1, squirming on her hip. She and her husband are well-travelled academics who decided to put down roots here two years ago.
Cumming was dismayed that her daughter thought everything came from stores – she even asked where they bought Daddy.
"I wanted her to be aware that it's possible to grow vegetables in the garden," Cumming says. "It's more of an educational value than anything else....Realistically, you will tend to buy most of your vegetables at the shop. But every little bit counts."
The Young Urban Farmers create their own soil mix, and never use chemicals, fertilizers or pesticides. Their gardens are planted in wooden boxes, each divided into 16 compartments for different plants. Tomatoes, herbs and strawberries are most popular choices.
The concept is similar to Square Foot Gardening. Popularized in the early 1980s, this movement involved small, intensively planted gardens that particularly suited beginners and those with disabilities, cut down on the need for weeding, and saved both water and work.
The Farmers' planters, typically four by four feet, can be pushed together like puzzle pieces. Most customers, however, have opted for just one.
"We've had more than enough," says Cumming. She waves goodbye as she crosses the street, basket in hand, to share the bounty, once again, with the neighbours.
The Farmers visit clients two or sometimes three times a week. They usually ride from garden to garden on bicycles. How green is that? And nowadays, they don't need much more than a pair of scissors for snipping.
"We have a very hands-on approach," Wong says.
These are the full-service gardens, where the Farmers do all
the work, from seeding to weeding, watering to harvesting. They had 14 to tend
this season. Most are in the pocket between Avenue Rd. and
One planter is $495 with full-service, $155 with basic service, but Wong says prices will increase.
The Farmers – Wong and fellow Queen's University grads Nancy
Huynh and Jing Loh – toil from February to September.
They aren't just learning on the job. Wong says they've helped to grow fruit
and veggies in their own gardens since they were kids. He lives at his parents'
house in
He is, of course, a big fan of vegetable gardens.
"You can see a direct correlation between the effort you put in and the results," he says. "Hopefully, we'll inspire more people to start their own vegetable garden."
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