 |
|||
 |
" I heard it |
||
January 5, 2010
· Cold snap has Florida growers feeling the heat
· GM crops included in British future food plan
· Honeybees learn differences in food temperature
· Whiteflies sabotage alarm system of plants – study
· Water! New book asserts it’ll be worth fighting over
Cold snap has Florida
(Miami Herald)
– From nursery growers in the Redland to strawberry farmers 250 miles north in
With temperatures expected to dip to 30 degrees in some
inland sections of South Florida Tuesday morning and the low- to mid-20s in
``As an industry, we're all very, very concerned,'' said Redland nursery owner Steven Leonard. ``I haven't slept the last couple of days, and probably won't for the next three or four.''
That's because after a brief but slight warm-up, another
major cold front could roll through by the weekend as well. The National
Weather Service predicts
For tourists, the unusual extended cold snap might cost them a good tan to show off back home. For the state's shrinking farming belt, it could be much costlier.
At stake for Leonard: Some 200 varieties of foliage worth $1.5 million at his 26-acre Sturon Nursery -- most of them tropical species highly vulnerable to frost. Sub-freezing temperatures would be ``lethal,'' Leonard said.
BELOW FREEZING
Portions of western Miami-Dade, Broward and
Forecasters and the Florida Department of Agriculture warned that Florida's two biggest cash crops -- citrus, with a harvest worth about $1 billion a year, and strawberries, fetching about $400 million -- could see even colder temperatures at the peak of the harvest season.
Industry representatives said little damage was reported
from Monday night's first frigid wave across
Andrew Meadows, a spokesman for Florida Citrus Mutual, said temperatures dropped to 26 in some groves but not for the four hours or more it takes to damage the fruit. Meadows said growers are optimistic but ``we'll all be watching the thermometer for the next several nights.''
GETTING COVERED
Ted Campbell, executive director of the Florida Strawberry
Growers Association, said growers in
Because they grow low to the ground and won't freeze until
it hits 28 degrees, strawberries can weather the cold better than many crops,
Freezing days are fairly typical in
COLD OF '89
The last time Leonard recalls it being so cold for so long in the Redland was 1989, which caused ``massive'' losses to the agriculture industry, he said.
``We will see some damage immediately, and then a week from now, we'll really see the extent of it,'' he added.
That's why he's getting such little sleep. It's the coldest at night, and so Leonard and his staff have worked around the clock, monitoring conditions and reacting in turn.
When temperatures near the freezing mark, Sturon will blast the crops with 70-degree water to fend off frost.
Some plants will also be covered with blankets, although that isn't possible with many varieties -- such as the 18-foot palm trees.
As of late Monday, there had been minimal damage to Sturon's two nurseries, but that could change the colder it gets.
GM crops included in British future food plan
(IrishExaminer.com) – BRITAIN’S first major food strategy for 60 years, which Environment Secretary Hilary Benn will launch at the Oxford Farming Conference today, will call for a sea change in the way people think about farming.
The document will also recommend a move towards accepting GM crops to create a "sustainable and secure food system for 2030.”
Rising to the Challenge is the theme of the conference, which will explore how farmers can respond to the immense agricultural challenge of feeding a world population of 9 billion by 2050 with minimal environmental impact.
The British Government strategy, which will set out its food plans for the next 20 years, will warn that agriculture must brace itself for sudden shocks, including natural disasters, volatile commodity prices and uncertain fuel supplies.
It will encourage consumers to throw less food away and to adopt leaner and healthier diets, to promote higher crop yields and to urge food producers to reduce the impact they have on the environment.
The strategy will also warn: "It is now clear that we face a big challenge in feeding the world. With a growing population, climate change and the pressure we are putting on land, we will have to produce more food sustainably.
"We also need to provide the right information for people to make more informed choices about what they eat. Diet will have a huge impact not only on our health and our economy, but most importantly on sustainability."
Prime minister Gordon Brown will
say in a foreword to the report that
He will say food production must increase "without damaging the air, soil, water and marine, resources, biodiversity and climate that we all depend on.
"We need to feed more people globally, many of whom want or need to eat a better diet. We need to tackle increasing obesity and encourage healthier diets."
Conference chairman Heather Peck said agriculture faces a huge challenge – feeding 9bn with less land, water, and oil, as well as greater climatic extremes.
The conference will also debate how businesses manage risk in the context of increased production and consumer and environmental demands.
Kerry Group chief executive Stan McCarthy will give a speech addressing how to manage a world-class food business built from strong co-operative roots
Professor Patrick Wall,
Honeybees learn differences in food temperature
(UCSD via ScienceDaily.com) – Biologists at UC San Diego have discovered that honeybees can discriminate between food at different temperatures, an ability that may assist bees in locating the warm, sugar-rich nectar or high-protein pollen produced by many flowers.
While other researchers had previously found hints that bees might have the ability to do this, the UCSD biologists provide the first detailed experimental evidence in a paper that will be published in the December 1 issue of the Journal of Experimental Biology.
"We show that honeybees have the ability to associate temperature differences with food," said James Nieh, an associate professor of biology who headed the study. "This information may help guide bees looking for food by allowing them to distinguish which bees are returning to the hive with the highest quality of food."
"Body temperature is seen in terms of its net caloric benefit to the other foragers," said Nieh. "The warmest forager in the nest is the one most likely to be visiting of the sweetest, highest quality food."
Nieh and researchers in his laboratory last year published a paper showing that bumblebees returning to their nests with higher quality pollen were warmer than bees that collected pollen with less protein. That gave the UCSD scientists evidence that bees may change their body temperature to reflect food quality, even for food that they do not consume and that has no direct metabolic impact on the bee.
Knowing that honeybees sense the temperature of returning foragers with their antennae, while these foragers conduct elaborate dances within the hive to communicate food location, Nieh and his colleagues wondered whether bees also sensed the temperature of their food. With the help of two undergraduate students, Tobin Hammer and Curtis Hata, he sought to find out whether bees possessed this ability.
Training bees to stick out their tongues in return for a sugary reward when the team touched a warm surface to a bee's antenna, the researchers found that bees could learn to identify warmth with food. Next, they tested whether the bees could learn to associate temperature differences with a food reward and discovered that this was also the case.
However, while the bees' abilities to recognize the temperature difference increased dramatically as the differences in temperatures rose, the scientists discovered that the bees were better at recognizing warm temperature differences than they were at cold temperature differences. In fact, the bees' abilities were twice as good at recognizing differences of 10 degrees Celsius above room temperature than they were at recognizing differences of minus 10 degrees Celsius below room temperature.
The researchers point out in their paper that this enhanced ability to distinguish warmer temperature differences could be an advantage for gathering nectar in many flowers. During the day, they note, temperatures in the centers of daffodils can be up to 8 degrees Celsius warmer than they are outside the flowers.
"A honeybee's ability to associate positive temperature differences with nectar rewards could also have a natural role inside the nest," the researchers conclude in their paper. "Honeybee foragers can elevate their body temperature after returning from a high-quality food source, and foragers returning from natural nectar or pollen sources increase their thoracic temperature when the colony has need for these resources."
The study was supported by the UC San Diego Opportunities for Research in Behavioral Sciences Program, which is supported by the National Science Foundation. ORBS is a program for high school students and undergraduates that provides research experience for students who are traditionally underrepresented in the sciences.
Whiteflies sabotage alarm system of plants
(ScienceDaily.com) – When spider mites attack a bean plant, the plant responds by producing odours which attract predatory mites. These predatory mites then exterminate the spider mite population, thus acting as a type of "bodyguard" for the plant. However, if the plant is simultaneously attacked by whiteflies, insects that are related to aphids, the plant becomes less attractive to the predatory mites and therefore more vulnerable to spider mites.
Together with German colleagues, researchers from the
Laboratory of Entomology at
The research team studied the strength of the plant's "cry for help" through a chemical analysis of the plant odour blend and found that one of the odour components (beta-ocimene) is produced in much lower quantities if the plant is not only attacked by spider mites, but also by whiteflies. The production of the odour decreases because of a lower expression rate of the plant gene that codes for a crucial enzyme in the production chain. When the researchers added ocimene to the odour of plants which were attacked by both species, the attraction of predatory mites was restored.
This recent breakthrough demonstrates that there are also herbivores that can interfere with a plant's "cry for help," possibly because the whiteflies attempt to interfere with the plant's defence system. Spider mites also produce more offspring on a plant under attack by whiteflies. For a spider mite, there are therefore two reasons why a bean plant which is being attacked by whiteflies is better than a bean plant that is not being attacked: more offspring and fewer bodyguards. It is therefore no surprise that the researchers found that the spider mite preferred plants infested with whiteflies above plants without them.
The results of this study are significant for integrated crop protection in which a combination of methods can be used to fight various pests infesting a crop. Integrated crop protection offers effective possibilities for environmentally safe pest control, and is based on a solid knowledge of the crop system and its complex of enemies. Once it becomes clear which insects weaken plant defence systems and which strengthen them, more focused research on environmentally-safe pest control will be possible, and people will no longer be caught off guard by unexpected interference from some pest species.
The fact that plants "cry for help" at all was discovered by the Wageningen research group in 1988. Since that time, various laboratories worldwide have continued studying this topic and it is now known that many -- if not all -- plants apply this type of defence. The research conducted worldwide has focused primarily on the situation in which plants are only attacked by a single herbivore. In nature, the situation is much more complex, however. Plants are involved in a continuous arms race with herbivorous insects which exploit the plant as food in a variety of ways. Spider mites suck the contents of parenchyma cells. Contrary to what their name suggests, whiteflies are not actually flies at all, but sap-sucking insects related to aphids, which suck from the vascular tissue located deeper in the plant. Some insects reinforce the plant's defence system which protects it from other predators.
Water! New book asserts it’ll be worth fighting over
(npr.org) – Just as wars over oil played a major role in 20th-century history, a new book makes a convincing case that many 21st century conflicts will be fought over water.
In Water: The Epic Struggle for Wealth, Power and Civilization, journalist Steven Solomon argues that water is surpassing oil as the world's scarcest critical resource.
Only 2.5 percent of the planet's water supply is fresh, Solomon writes, much of which is locked away in glaciers. World water use in the past century grew twice as fast as world population.
"We've now reached the limit where that trajectory can no longer continue," Solomon tells NPR's Mary Louise Kelly. "Suddenly we're going to have to find a way to use the existing water resources in a far, far more productive manner than we ever did before, because there's simply not enough."
One issue, Solomon says, is that water's cost doesn't reflect its true economic value. While a society's transition from oil may be painful, water is irreplaceable. Yet water costs far less per gallon — and even less than that for some.
"In some cases, where there are large political subsidies, largely in agriculture, it does not [cost very much]," Solomon says. "In many cases, irrigated agriculture is getting its water for free. And we in the cities are paying a lot, and industries are also paying an awful lot. That's unfair. It's inefficient to the allocation of water to the most productive economic ends."
At the same time, Solomon says, there's an increasing feeling in the world that everyone has a basic right to a minimum 13 gallons of water a day for basic human health. He doesn’t necessarily have an issue with that.
"I think there's plenty of water in the world, even in the poorest and most water-famished country, for that 13 gallons to be given for free to individuals — and let them pay beyond that," he says.
Solomon says the world is divided into water haves and
have-nots.
In his book he writes, "Consider what will happen in
water-distressed, nuclear-armed, terrorist-besieged,
overpopulated, heavily irrigation dependent and already politically unstable
Solomon notes some good water news, too. The
"Our water use between 1900 and 1975 actually tripled relative to population growth," he says. "Since 1975 to the present day, it has flat-lined. And we still had a population increase of about 30 percent and our GDP continued to grow. So it's an amazing increase in water productivity."
End Transmission