April 18, 2012
Advocates of his "no-till farming" technique say it could provide the low-cost, environmentally-friendly crops the agricultural industry has sought for many years.
Starkey's cropland looks like a tangle of corn stalks, crimson clover and ryegrass, far different from the impeccably-plowed fields of most farms.
"Over a period of 12 years, we're now 100 percent no-till," said the corn and soybean farmer, who also is a supervisor with the Hendricks County Soil and Water Conservation District.
The biggest departure from traditional farming involves the plowing, also known as tilling.
Plowing aerates the soil, eliminates weeds and helps with nutrient recovery.
However, plowing also erodes the soil and kills part of the organic life that grows in it.
No-till farming helps to rebuild the "nutrient capital" of farmland that now is dependent on fertilizers, Starkey said.
The technique, also known as "conservation farming," started about 20 years ago by following the "three pillars" of the method: cover crops, no-till and crop rotation.
Cover crops refer to plants like clover, ryegrass and alfalfa that form a carpet to protect the soil from erosion while also trapping nitrogen from the air and storing it in nodules on the roots of plants to fertilize the ground.
In April, just before the sowing of seeds, weed killer is sprayed on the cropland.
"When we actually kill these legume plants, these nodules then become an organic source of nitrogen that breaks down much more slowly than commercial fertilizer," said Barry Fisher, a no-till farming expert for the US Agriculture Department's National Resources Conservation Service.
"That's a time release form of nitrogen... that will spoon feed the nitrogen to the corn crop coming here," Fisher said.
Cover crops maximize the use of the soil's natural fertilizers, which can be a better alternative than manufactured fertilizers sinking into groundwater after heavy rain, he said.
Direct seeding for cash crops requires special tractors that dig narrow furrows, inject the seeds and close the hole in one motion, without scarring the land.
No-till crops like corn and soybeans feed off the rich nutrients in decomposing plants from the previous season and from cover crops.
"Conservation tillage systems, with today's planting
equipment, with today's technologies... have been yielding consistently the
same" as traditional farming, said Tony Vyn, professor of agronomy at
About 35 percent of US crops are grown with no-till farming, according to the US Agriculture Department. For soybeans, about half the crops are raised with no-till techniques.
The federal government is encouraging no-till farming by providing subsidies for cover crop seeds and the special equipment they require, which can run up to 50 percent of the cost.
(EurekaAlert!) – In the race to breed better crops to feed the increasing world population, scientists at The University of Nottingham are using maths to find out how a vital plant hormone affects growth.
Gibberellin is a hormone which plays a key part in development throughout the plant, from the root to the flowers and leaves. The hormone works within a complex network of molecules inside the plant, translating signals from the environment into responses in the plant so it can adapt and survive.
Many of the crop varieties developed during the global agricultural 'green revolution' of the 1960s were found to have genetic mutations in this important pathway. Now a team of scientists has applied mathematical approaches to understand how this 'green revolution' hormone works to control plant growth. They have then been able to show how these interactions result in changes in hormone levels that could be key to breeding improved crop varieties in the future.
Leading the research at
A second piece of research in this area has looked at the gibberellin distribution along a growing root, a factor which also affects growth and development. A team led by Professor of Theoretical Mechanics at The University of Nottingham, John King, has used multiscale mathematical modelling to probe how the gibberellin signalling network controls root growth. Work by researcher Leah Band revealed that dilution of gibberellin in rapidly expanding cells can explain why growth finally ceases.
The study led by Dr Owen highlights the importance of interactions between several key feedback loops within the gibberellin signalling network. Professor King's team combined that signalling network with a model for the elongation of a root, to predict how DELLA proteins (key components within the gibberellin signalling network which normally suppress growth), increase along the root, which explains experimental observations of growth rates.
Both studies have just been published in the leading academic journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).
(USDA-ARS) – A U.S. Department of Agriculture (USDA) scientist has shown researchers and plant breeders a better way to handle the massive amounts of data being generated by plant molecular studies, using an approach that should help speed up development of improved crop varieties.
Jean-Luc Jannink, who is with the Agricultural Research Service (ARS) Plant, Soil and Nutrition Research Unit at the agency's Robert W. Holley Center for Agriculture and Health, in Ithaca, N.Y., has demonstrated that by using a statistical approach known as Genomic Selection (GS), scientists can capture and exploit more of the data produced by the growing number of studies focused on DNA sequences found in plant genomes. GS is currently used in cattle breeding.
ARS is the principal intramural scientific research agency in USDA. This research supports the USDA priorities of improving agricultural sustainability and promoting international food security.
Scientists and plant breeders increasingly use molecular tools to develop improved crop varieties. By identifying genes associated with desirable traits, they don't have to wait to observe crops grown from seeds.
But molecular tools require analyzing massive amounts of data, and important traits like drought tolerance and yield are the result of the combined actions of multiple genes, each with a small effect. These genes are called quantitative trait loci (QTLs), and the conventional Marker-Assisted Selection (MAS) approach to handling molecular data has limited power to detect small-effect QTLs and estimate their effects.
Jannink's recommended GS approach exploits more data by including all of the small-effect QTLs and estimating the effects of all of the known genetic markers in a plant population.
Jannink and his colleagues recently constructed statistical models, using both GS and MAS approaches, and compared how well they could predict values associated with 13 agronomic traits in crosses made from a "training population" assembled for the study. They gauged the model's accuracy by comparing their predictions with field observations of 374 lines of wheat.
The results showed the GS approach was more accurate at predicting trait values. Jannink had similar success in a study using oats. Both studies were published in The Plant Genome. The work is expected to speed up molecular breeding efforts and should prove extremely useful, given the pace of advances in DNA technology.
– By mating with nearly 100 males, queen bees on isolated islands avoid
inbreeding and keep colonies healthy. The results, published in the current
issue of PLoS ONE, focused on giant honey bee colonies on
"We believed that the island bees would show evidence of the founder effect, or random genetic changes in an isolated population, on a unique sex determination gene from the mainland bees," he said. "At first we were surprised when we couldn't document this effect. Looking at it further, I asked myself, 'Why didn't I think of this before?'"
When compared to bees, humans have a rather simplistic sex-determination process. In females, the two sex-determination chromosomes are the same, and in males the two chromosomes are different. With bees, however, the combinations of complementary sex determination genes, or CSDs, determine the sex and the societal role of the bees.
One particular gene can have alleles -- the "flavor" of genes. In humans, they dictate hair and eye color. In bees, though, they are responsible for creating females (worker bees), fertile males (that mate with the queen) or infertile males (diploid males which serve no purpose).
The voila moment came once Huang estimated the bees' mating habits and the potential of CSD allele combinations. That's when he understood why he couldn't confirm the founder effect. Keeping the CSD mix diverse is one of the keys to maintaining a healthy hive, he said.
The island queens carry around 40 CSD alleles. Since they mate with nearly 100 males -- each also harboring around 40 alleles -- the high number of healthy genetic combinations keeps the gene pool diverse. By using natural selection to create healthy offspring, the bees perpetuate a healthy colony.
In comparison, if the island bees adopted the breeding habits of fire ants, with queens mating with a single male, inbreeding could wreck the off-shore claves or distinct populations of bees. The devastating change would reduce the fitness of the hive, decreasing the female workforce, as well as lowering the number of mating males.
What would be left would be an unhealthy hive with higher numbers of diploid or infertile males, with the same alleles, Huang said.
By extending his research beyond
"We failed to find any clustering of the bees' CSD
alleles according to their geographical origin; the
(The Washington Post) -- “Let’s throw some bombs,” a young woman calls out, waterproof floral purse swinging on her shoulder and Laura Ingalls braids flying behind her as a band of 25 followers cheer, “Cool!”
They rush toward a drab vacant lot in Shaw. Some climb up onto the back of a truck to get better aim at their target. But these bombers aren’t likely to appear on any terrorist list or even get arrested. They’re throwing “seed bombs,” golf-ball-size lumps of mud packed with wildflower seeds, clay and a little bit of compost and water, which they just learned to make at a free seed-bombing workshop for Washington’s guerrilla gardeners.
The benign bombing is part of a larger phenomenon known as
activist gardening that is taking off this spring in cities such as
“Guerrilla gardening is urban gardening and food justice. It’s just this really cool mix,” says Emmy Gran, 25, who is teaching seed-bombing in a floppy sun hat at a recent Saturday morning workshop in the courtyard of Old City Green, a gardening store in Shaw. “But it’s controversial, too. If you see an abandoned, neglected lot and you decide to do something about it by planting vegetables and herbs, are you an occupier? It’s kind of radical, in some ways.”
And every radical movement needs graffiti. Gran hauls out her Cuisinart to make the green “spray-paint” required for gardening activism’s biodegradable moss graffiti. Ingredients: moss, a half teaspoon of sugar and beer or yogurt which, when blended, will stick to walls. (“You can also use buttermilk,” she adds.) With a light rain starting to fall, the group walks over to a curb near the garden store and uses the gloppy mixture to write “Nourish, Grow, Shaw” in big, moss-green letters.
Activist gardening is the latest face of social justice in the
District. Forget living in a tent in
“It’s all a lot less devious than it seems,” says Ellen
Abramowitz, 22, who works for the
One flower at a time
Gran tells her students — most of whom were born in the
1980s — that guerrilla gardening dates from the late-1960s establishment of
People’s Park in
“I think it’s also a democratic statement and an experiment
in re-creating space,” says
They’re doing it one flower at a time. The bombs will — in theory — bloom into bachelor’s buttons and baby’s breath, forget-me-nots and marigolds when the truffle-size balls hit, then expand. It also helps if there’s a healthy spring rain, said Scott Aker, head of horticulture for the U.S. National Arboretum. If the bombs are launched into a sunny space where there’s not too much other vegetation present, then he gives the seeds a 70 percent chance of blooming. “But either way, it sounds like great fun,” Aker says. “On your commute, you can toss one out the window.”
District police say that guerrilla gardening technically constitutes unlawful entry, a misdemeanor. But, says D.C. police spokeswoman Gwendolyn Crump, “nothing like this has come to our attention.” Although there have been reports of gardens being bulldozed to make way for development, gardeners say the issue of small-scale gardening is typically hashed out between property owners and the people doing the planting.
Permits for planting
Not everyone at Gran’s workshop is a guerrilla gardener.
Some of the young people attending the class — run by
This spring Sarah McLaughlin, 25, and her boyfriend Josh
Singer, 31, started a community “parken” on a 2.7-acre parcel of unused land
“We’re a real D.C. love story,” McLaughlin says with a laugh
as Singer puts his soil-stained arm around her after a long day of gardening.
The couple fell in love at the Occupy D.C. camp in
“We saw the land near where we have a group house, and we
wanted to use green space to build community,” says Singer, who’s wearing an “I
Dig Trees” T-shirt under his Carhartt jacket. So far, McLaughlin and Singer
have helped the community plant 59 garden plots in
Singer has put $3,000 in soil and other supplies on his credit card. But he hopes the garden will flourish and that he will eventually obtain sufficient funding and grants to add a dog park, a butterfly/native plant garden and an outdoor classroom.