Seedless Cherimoya, the Next Banana?

Mark Twain called it "the most delicious fruit known to man." But the cherimoya, or custard apple, and its close relations the sugar apple and soursop, also have lots of big, awkward seeds. Now new research by plant scientists in the United States and Spain could show how to make this and other fruits seedless.

Going seedless could be a big step for the fruit, said Charles Gasser, professor of plant biology at UC Davis.

"This could be the next banana -- it would make it a lot more popular," Gasser said. Bananas in their natural state have up to a hundred seeds; all commercial varieties, of course, are seedless. A paper describing the work is published March 14 in the journal Proceedings of the National Academy of Sciences.

Researchers José Hormaza, Maria Herrero and graduate student Jorge Lora at the Consejo Superior de Investigaciones Cientificas in Malaga and Zaragoza, Spain, studied the seedless variety of sugar apple. When they looked closely at the fruit, they noticed that the ovules, which would normally form seeds, lacked an outer coat.

They looked similar to the ovules of a mutant of the lab plant Arabidopsis discovered by Gasser's lab at UC Davis in the late 1990s. In Arabidopsis, the defective plants do not make seeds or fruit. But the mutant sugar apple produces full-sized fruit with white, soft flesh without the large, hard seeds.

The Spanish team contacted Gasser, and Lora came from Malaga to work on the project in Gasser's lab. He discovered that the same gene was responsible for uncoated ovules in both the Arabidopsis and sugar apple mutants.

"This is the first characterization of a gene for seedlessness in any crop plant," Gasser said.

Seedless varieties of commercial fruit crops are usually achieved by selective breeding and then propagated vegetatively, for example through cuttings.

Discovery of this new gene could open the way to produce seedless varieties in sugar apple, cherimoya and perhaps other fruit crops.

The discovery also sheds light on the evolution of flowering plants, Gasser said. Cherimoya and sugar apple belong to the magnolid family of plants, which branched off from the other flowering plants quite early in their evolution.

"It's a link all the way back to the beginning of the angiosperms," Gasser said.

The work was funded by grants from the Spanish government, the European Union and the U.S. National Science Foundation

Read more »

Agriculture and Food,

{[['']]}

Dairy Farmer Finds Unusual Forage Grass

A U.S. Department of Agriculture (USDA) grass breeder has rediscovered a forage grass that seems just right for today's intensive rotational grazing.

A farmer's report of an unusual forage grass led Michael Casler, an Agricultural Research Service (ARS) geneticist at the agency's U.S. Dairy Forage Research Center in Madison, Wis., to identify the grass as meadow fescue. Meadow fescue has been long forgotten, although it was popular after being introduced about 50 to 60 years before tall fescue.

ARS is USDA's principal intramural scientific research agency.

Casler has developed a new variety of meadow fescue called Hidden Valley, and its seed is being grown for future release.

Non-toxic fungi called endophytes live inside meadow fescue, helping it survive heat, drought and pests. Unlike the toxic endophytes that inhabit many commercial varieties of tall fescue and ryegrass, meadow fescue does not poison livestock.

Charles Opitz found the grass growing in the deep shade of a remnant oak savannah on his dairy farm near Mineral Point, Wis. He reported that the cows love it and produce more milk when they eat it. Casler used DNA markers to identify Opitz's find.

Meadow fescue is very winter-hardy and persistent, having survived decades of farming. It emerged from oak savannah refuges to dominate many pastures in the Midwest's driftless region, named for its lack of glacial drift, the material left behind by retreating continental glaciers.

Casler and his colleagues have since found the plant on more than 300 farms in the driftless region of Wisconsin, Iowa and Minnesota. Geoffrey Brink, an ARS agronomist working with Casler, discovered that meadow fescue is 4 to 7 percent more digestible than other cool-season grasses dominant in the United States.

In another study, meadow fescue had a nutritional forage quality advantage over tall fescue and orchardgrass that may compensate for its slightly lower annual yield further north, as reported in the Agronomy Journal. Also, the yield gap begins to close with the frequent harvesting involved in intensive grazing.

Read more »

Agriculture and Food,

{[['']]}

Large Regional Changes in Farmland Area Predicted

The effects of climate change and population growth on agricultural land area vary from region to region, according to a new study by University of Illinois researchers

Regions with relative high latitudes -- China, Russia and the U.S. -- could see a significant increase in arable land in coming years, but Africa, Europe and India and South America could lose land area.

Civil and environmental engineering professor Ximing Cai and graduate student Xiao Zhang published their findings in the journal Environmental Research Letters.

While most other studies of climate change and agriculture have focused on projected crop yields, the Illinois researchers assessed global and regional land availability. Using international land and climate datasets and remote-sensing land-use maps, they systematically studied worldwide changes in soil temperature and humidity with a resolution of one square kilometer.

"This study presents the main patterns and trends of the distribution of potential arable land and the possible impacts of climate change from a biophysical perspective," Cai said. "The possible gains and losses of arable land in various regions worldwide may generate tremendous impacts in the upcoming decades upon regional and global agricultural commodity production, demand and trade, as well as on the planning and development of agricultural and engineering infrastructures."

Cai and Zhang's model allowed them to address the many sources of uncertainty in trying to predict climate change, such as levels of greenhouse gas emissions, climate model uncertainty and ambiguity in land-use classification. They applied the model to several projected scenarios to uncover both regional and global trends in land availability.

When considering effects of climate change, residential sprawl as population grows and natural conservation, the global total of potential arable land in all scenarios decreased by the end of the 21st century, by a margin of 0.8 to 4.4 percent. However, much larger changes were predicted regionally. For example, arable land area could increase by 37 to 67 percent in Russia, while Africa could lose up to 18 percent of its farmland.

"Although the magnitudes of the projected changes vary by scenario, the increasing or decreasing trends in arable land area are regionally consistent," Cai said.

Next, the researchers will conduct more detailed regional studies to confirm their global findings. They hope to use their projections to evaluate world food production, demand and trade, and the corresponding implications for policies and investments.

The Energy Bioscience Institute at the U. of I. and the U.S. Department of Agriculture supported this work.

Read more »

Agriculture and Food,

{[['']]}

Anaerobic Digestion on Farms Could Turn Agriculture Green

Research carried out by the Rural Economy and Land Use Programme has shown that small scale digesters on farms could be profitable for farmers, good for the environment and help the UK meet targets on green energy and greenhouse gas emissions.

A typical dairy farm could supply most of the electricity it needs to milk the cows, by converting their manure into energy. And it would help the Government to hit green energy targets and cut greenhouse gas emissions, according to researchers from the UK research councils' Rural Economy and Land Use Programme.

The interdisciplinary project, based at the universities of Southampton and Reading, has researched the potential for small-scale farm-based anaerobic digestion plants. It found that relatively small digesters could be economically viable when fed with mixtures of animal slurries and imported wastes or energy crops, and had the potential to boost the profits of both arable and dairy farms.

Wider adoption of the technology would also help farming to become greener. Digesting the slurry produced by one dairy cow has the potential to reduce methane emissions by 25 kg, and generate 1000 kWh of electricity per year -- equivalent to three months' electricity consumption for an average household,

The digestate left at the end of the process is a valuable fertiliser if spread on the land, reducing the amount of money farmers spend on artificial fertilisers -- and also saving the CO₂ emissions involved in their production.

Anaerobic digestion is a very flexible technology, which may be used to process a wide range of agricultural crops, crop residues, animal wastes and imported food wastes, into usable energy.

The team also researched public attitudes to the building of anaerobic digestion plants in rural areas. Consumers tended to support the idea, particularly if cattle and pig manures were used to feed the digester, but most were also happy for food crops to be used. They thought that the most important benefit was that the digesters provide an alternative to landfill for organic waste, including waste food.

Professor Charles Banks from the University of Southampton who led the research said: "Other European countries have forged ahead with this technology. But although the UK Government has expressed its support, this has still not led to widespread adoption of the technology on farms.

"This research has shown that there is an economic incentive for farmers, but further encouragement may be necessary, and perhaps some financial support for demonstration projects. Widespread adoption could provide multiple benefits, not just for the farmer but also for the environment."

Read more »

Agriculture and Food,

{[['']]}

Plasticity of Plants Helps Them Adapt to Climate Change

An international study, with Spanish participation, has shown that the phenotypic plasticity of plants, which enables them to change their structure and function, helps them to adapt to environmental change. This research will make it easier to anticipate plants' response to current climate change.

The study, which has been published in Trends in Plant Science, provides an overview of plants' molecular and genetic mechanisms, which is important for ecologists, physiologists and molecular biologists, since it covers the prime requirements for anticipating plants' response to global change.

The results show that plants in natural and agricultural systems have "the capacity to adapt to a changing environment without requiring any evolutionary changes, which always happens over several generations," Fernando Valladares, one of the authors of the paper and a researcher at the National Museum of Natural Sciences (CSIC), said.

All plant species exhibit a greater or lesser degree of plasticity. "Various studies suggest that species from more heterogeneous and changing environments have greater degrees of plasticity. For example, plants from these environments have great root plasticity in order to be able to take better advantage of fertile and damp areas and to avoid sterile, dry ones," Valladares explains.

Plants' pigmentation, root length, leaf mass and efficiency of water use are some of the leading indicators used to study the phenotypic plasticity of plant organisms.

"The differences in plasticity and its mechanisms allow us to better understand why various plant species grow where they do. This will enable us to project their most likely ranges in climate change scenarios," the researcher says.

Less productivity, greater survival

The advantages of plants changing their structure and function in the face of environmental change "could lead to the selection -- in the case of crops -- of more plastic varieties, which may not necessarily be the most productive, nor have the most easily-predictable productivity," the scientist stresses.

According to Valladares, the next step is "to understand the mechanisms that underlie plasticity, such as epigenetics -- non-genetic factors that determine an organism's development -- and how this impacts on the biological efficacy of wild species or on the long-term yield of agricultural species."

Read more »

Agriculture and Food,

{[['']]}

Does Corn have an expiry date?

Many of us would not drink milk past the expiry date, maybe on a dare but even then many of you are probably a little uneasy with just the thought of this. As corn harvest is slowed down due to weather or full elevators I get that same uneasy feeling I get thinking of drinking spoiled milk. In 2010 we planted our corn early and had great heat and rains throughout the summer in much of the corn producing areas of Ontario and Quebec and yet we are somewhat surprised that the standability is starting to weaken. Could it be that we have went past the expiry date on corn stalks and roots?

I would say yes. Current moisture levels are below 20% and the corn was fully mature (black layer) over a month ago, so the plant has been dead for a while. Dead plant material rots. If you add moisture (heavy dews, frequent rains even frost) it rots faster, plain and simple. Add high winds and rotting stalks break. One of the main differences I see in traveling from a Western corn area (mid west US) to an Eastern corn area is the higher level of moisture and therefore rot organisms that the corn plant must survive. In the East our expiry date is less than the West. Also, how the plants partitions its energy resources (sugars) – yield or plant health affects the expiry date of corn. If every plant only has one 2 gallon pail of energy to use where is it going to use it (ex. 1/2 gallon for stalks, 1/2 gallon for roots and 1 gallon for grain) each hybrid is different on how it partitions its 2 gallon bucket. Generally, the very high yielding genetics put more of its bucket into grain and the stalks and roots may run out as we go later into the season (shorter expiry date). Average yield with consistent standability may use more of its 2 gallon bucket for stalks and roots and therefore stand longer but yield less (long expiry date).

So what do I do as a grower? Harvest your short expiry date hybrids early to maximize the yield of those hybrids. This fall select a portfolio corn genetics that have long and short expiry dates.

Have a safe harvest.

Source: http://nkcropbarometer.wordpress.com/

Read more »

Agriculture and Food,

{[['']]}

Harvest Tips for Mouldy Corn

Some area’s in Ontario are seeing a higher levels of ear mould this year. I have included the harvest tips used in previous years.

First using the inserted picture determine if you are at risk. A quick method of determining if you are at risk includes scouting 100 plants from the field (5 areas of 20 ears each). Fields with 25 % of the ears having mould growth should be harvested sooner rather
than later.

A) Prioritize your corn harvest and storage. If producers have 2009 crop corn still left on the farm it is important to not mix it with potentially mouldy corn from this harvest. Livestock producers, especially hog, will want to scout fields, sample and test for mycotoxins in order to store their cleanest corn for feeding purposes. Cash croppers are advised that the same process of keeping clean corn segregated from mouldy corn may result in some increased marketing opportunities over the upcoming months.
B) As a general rule, harvest infected fields early. Mycotoxin levels have the potential to build the longer you leave the corn in the field. Once corn moisture is below 18%, mould fungi become dormant and cease to produce mycotoxins.
C) High temperature drying stops mould growth and mycotoxin production but does not reduce mycotoxins already present. Optimum temperature for mould growth is 28oC; mould stops growing at >30 degrees C. Quick drying is preferred over low heat drying. Be wary of low temperature in bin dryers for mouldy corn and be sure proper ventilation requirements are met for storing dry corn.
D) Leave tip kernels attached to the cob if possible by running the combine at full capacity with concave settings open and cylinder speed set low. Screens on the bottom of the grain elevator, the bottom of the return elevator and on the unload auger will also help screen out the fines.
E) Set the combine to provide high levels of wind to blow out the lighter infected kernels. Gibberella ear rot infection results in kernel damage. As noted above, cob pieces and the fines (kernel tips and red dog) contain higher concentrations. Be careful combine
adjustments do not result in kernel damage. The sample could be downgraded and increase potential storage problems.
F) Additional post-combine grain cleaning with rotary screen type cleaners has been shown to be effective in reducing mycotoxin levels in the remaining grain. This
method has the most significant impact on grain samples with low to moderate mycotoxin levels.

Check your fields before you harvest and develop a plan if you do see ear mould infection. Have a safe harvest.

Source: http://nkcropbarometer.wordpress.com/

Read more »

Agriculture and Food,

{[['']]}

First Documented Case Of Pest Resistance To Biotech Cotton

A pest insect known as bollworm is the first to evolve resistance in the field to plants modified to produce an insecticide called Bt, according to a new research report.

Bt-resistant populations of bollworm, Helicoverpa zea, were found in more than a dozen crop fields in Mississippi and Arkansas between 2003 and 2006.

"What we're seeing is evolution in action," said lead researcher Bruce Tabashnik. "This is the first documented case of field-evolved resistance to a Bt crop."

Bt crops are so named because they have been genetically altered to produce Bt toxins, which kill some insects. The toxins are produced in nature by the widespread bacterium Bacillus thuringiensis, hence the abbreviation Bt.

The bollworm resistance to Bt cotton was discovered when a team of University of Arizona entomologists analyzed published data from monitoring studies of six major caterpillar pests of Bt crops in Australia, China, Spain and the U.S. The data documenting bollworm resistance were first collected seven years after Bt cotton was introduced in 1996.

"Resistance is a decrease in pest susceptibility that can be measured over human experience," said Tabashnik, professor and head of UA's entomology department and an expert in insect resistance to insecticides. "When you use an insecticide to control a pest, some populations eventually evolves resistance."

The researchers write in their report that Bt cotton and Bt corn have been grown on more than 162 million hectares (400 million acres) worldwide since 1996, "generating one of the largest selections for insect resistance ever known."

Even so, the researchers found that most caterpillar pests of cotton and corn remained susceptible to Bt crops.

"The resistance occurred in one particular pest in one part of the U.S.," Tabashnik said. "The other major pests attacking Bt crops have not evolved resistance. And even most bollworm populations have not evolved resistance."

The field outcomes refute some experts' worst-case scenarios that predicted pests would become resistant to Bt crops in as few as three years, he said.

"The only other case of field-evolved resistance to Bt toxins involves resistance to Bt sprays," Tabashnik said. He added that such sprays have been used for decades, but now represent a small proportion of the Bt used against crop pests.

The bollworm is a major cotton pest in the southeastern U.S. and Texas, but not in Arizona. The major caterpillar pest of cotton in Arizona is a different species known as pink bollworm, Pectinophora gossypiella, which has remained susceptible to the Bt toxin in biotech cotton.

Tabashnik and his colleagues' article, "Insect resistance to Bt crops: evidence versus theory," will be published in the February issue of Nature Biotechnology. His co-authors are Aaron J. Gassmann, a former UA postdoctoral fellow now an assistant professor at Iowa State University; David W. Crowder, a UA doctoral student; and Yves Carrière, a UA professor of entomology. Tabashnik and Carrière are members of UA's BIO5 Institute.

"Our research shows that in Arizona, Bt cotton reduces use of broad-spectrum insecticides and increases yield," said Carrière. Such insecticides kill both pest insects and beneficial insects.

To delay resistance, non-Bt crops are planted near Bt crops to provide "refuges" for susceptible pests. Because resistant insects are rare, the only mates they are likely to encounter would be susceptible insects from the refuges. The hybrid offspring of such a mating generally would be susceptible to the toxin. In most pests, offspring are resistant to Bt toxins only if both parents are resistant.

In bollworm, however, hybrid offspring produced by matings between susceptible and resistant moths are resistant. Such a dominant inheritance of resistance was predicted to make resistance evolve faster.

The UA researchers found that bollworm resistance evolved fastest in the states with the lowest abundance of refuges.

The field outcomes documented by the global monitoring data fit the predictions of the theory underlying the refuge strategy, Tabashnik said.

Although first-generation biotech cotton contained only one Bt toxin called Cry1Ac, a new variety contains both Cry1Ac and a second Bt toxin, Cry2Ab. The combination overcomes pests that are resistant to just one toxin.

The next steps, Tabashnik said, include conducting research to understand inheritance of resistance to Cry2Ab and developing designer toxins to kill pests resistant to Cry1Ac.

Although preparation of this article was not supported by organizations that may gain or lose financially through its publication, the authors have received support for other research from Monsanto Company and Cotton, Inc. One of the authors (B. T.) is a co-author of a patent application filed with the World Intellectual Property Organization on engineering modified Bt toxins to counter pest resistance, which is related to research published in 2007 (Science 318: 1640-1642. 2007).

Source

Read more »

Agriculture and Food,

{[['']]}

Technology Protects Cotton from Caterpillar's Appetite

The furry-looking insects start their development smaller than the head of a pin, but the caterpillars soon develop an appetite for cotton as big as the crop.

To demonstrate the insects' destructive power, Clemson University entomologist Jeremy Greene planted two cotton varieties -- one genetically modified to provide protection from caterpillars, one not -- in a demonstration field at the Edisto Research and Education Center.

The non-protected cotton was planted in a pattern that spelled the word "Tigers." Aerial photographs taken near harvest show that while the genetically modified crop survived intact, the unprotected plants provided three square meals a day for the crop-hungry herbivores.

The demonstration crop was planted in late May last year and grew through the summer.

"We wanted to show the kind of damage caterpillars can do when they're allowed to eat unprotected cotton freely," Greene said.

Cotton is a multimillion dollar crop in the Palmetto State involving hundreds of farms and thousands of jobs.

Nearly all cotton varieties planted in South Carolina contain genes found in the naturally occurring Bacillus thuringiensis, or Bt, that help the plant make its own insecticide.

Bt cotton is genetically modified with specific genes from Bacillus thuringiensis. Think of it as in-plant insecticide, Greene said. This technology has been commercially available since 1996, but improvements over the years have enhanced the control of major pests.

The plant makes the proteins just like the bacterium does. The particular strain of Bacillus thuringiensis available in cotton, which was planted for the demonstration, works only on immature lepidopterans, or caterpillars. Lepidoptera is the insect order for moths and butterflies. The toxic proteins have no ill effects on other organisms.

"During 2010, we had a very high population of bollworm that infested cotton acres at the Edisto research center," Greene said. "We planted a non-Bt variety where you see the word 'Tigers' and a two-gene Bt cotton where you see the fluffy white cotton lint."

The striking difference in appearance is due to bollworms eating all of the green cotton bolls in the non-Bt variety that did not have protection from the insects.

Greene applied no insecticides to control caterpillars in this field, so the difference between the Bt and non-Bt varieties is illustrated clearly.

A color-coded yield map, produced by precision agriculture specialist Will Henderson at the Edisto center, illustrates the crop after harvest using one of the center's pickers that is equipped with a yield monitor. The map shows "good" yields in green and "bad" yields in red.

The damage potential of important lepidopteran species, such as bollworm, is not new, Greene said. Moths have flown into fields, laid eggs and hatched as injurious caterpillars for decades.

Transgenic Bt technology and its improvement over the years are relatively recent advances that represent effective, economical and environmentally friendly control of these insects in agriculture, he said.

"We know what they can do to non-Bt cotton versus Bt cotton -- the photographs speak for themselves," Greene said.

Source

Read more »

Agriculture and Food,

{[['']]}