Peach Genome Released, Pear Ripening Gene, Carbon Sequestration

Peach Genome Provides High-resolution Model for Fruit Breeders

Realizing a decade-long dream, an international team of scientists publicly released the peach genome sequence, the first genome completed for crops in the Rosaceae family. Improvement of traits such as enhanced flavor and disease resistance are now a more efficient prospect for peach and other tree fruit. This new resource will enable targeted, DNA-informed breeding, an approach to developing tasty and nutritious fruit that is both more precise and more economically viable than traditional breeding.

Knowledge of the genetic makeup of the peach could have far-reaching implications for the future of peaches and related Rosaceae plants such as almonds, blackberries, apples, cherries, plums, raspberries, roses, strawberries and trees such as poplar, citrus and chestnut.

“Having access to the genome sequence can save researchers literally years of work,” said Dorrie Main, associate professor of bioinformatics in the WSU Department of Horticulture and Landscape Architecture. Main, who has been working on the peach genome project since 2001, said that making the data publicly available means that scientists investigating genes controlling important traits in peach or other plants will be able to use the information immediately.

WSU sweet cherry breeder Nnadozie Oraguzie is excited about the release. “This information will be of immediate value in my breeding program and allow us to make much quicker progress to develop superior new cultivars for Washington and Oregon cherry growers.”

Jim McFerson, manager of the Washington Tree Fruit Research Commission, agreed. “It is tremendously exciting to know that WSU, OSU and USDA researchers will now have access to this critical genomic tool, which has direct applicability to our breeding and physiology programs in apple, cherry, and pear. Our investment in bringing world-class faculty and cutting-edge technology to the Pacific Northwest is paying off. It gives both our researchers and industries a real competitive advantage as well as contributing to the world’s scientific knowledge base.”

“There’s an impression that the DNA sequence will encourage plant genetic modification,” said Cameron Peace, assistant professor of tree fruit genetics in the WSU Department of Horticulture and Landscape Architecture. “That’s unlikely in tree fruit, because there is so much useful diversity out there, such as that stockpiled in collections or hiding in abandoned old orchards and the wild forests of Asia. Previously, breeders could only judge genetic worth by tree performance and fruit appearance, but with the DNA information from the peach genome the genetic potential of every tree can be examined directly. This unlocks a deep treasure chest, putting the riches of biodiversity into our hands.”

“With its small size and high resolution, the peach genome serves as a model. As we’ve been able to identify many interesting genes for breeders, the same genes in other crops can be readily detected and deciphered,” Main said. “The DNA code for ripening or juiciness, for example, is the same in many plants. Understanding the fundamental biology of fruit quality allows enhancement of these attributes for each crop.”

Bioinformaticists such as Main couple the number-crunching power of computers with advanced mathematical techniques to analyze DNA and identify functioning genes. Currently, she and her colleagues are involved in integration and dissemination of genomic information for many species of plants, ranging from cacao to almond to roses.

Pear Gene Discovery Will Benefit Growers, Consumers

Two of the most popular and prevalent pears grown in the Pacific Northwest are Bartlett and D’Anjou. While the reticent D’Anjou actually needs near-freezing temperatures to initiate ripening, the Bartlett is not so demure. A crop of Bartletts will get very ripe, very fast, all at once.

This frustrates consumers because it means the Bartlett season is short, and the pears become overripe before they can be eaten. It also frustrates growers.

“The Lewiston Tribune last fall had an article featuring a local Bartlett grower who was literally giving away cases of pears because they all ripened simultaneously and out of control,” said Christopher Hendrickson, a graduate student in the WSU Department of Horticulture and Landscape Architecture.

Now, WSU scientists have discovered a gene they believe plays a role in pear ripening. So that quick-to-ripen and easily bruised Bartlett pear may actually make it out of the orchard and home from market without turning brown and mushy.

Working on pear research in the lab of Amit Dhingra, assistant professor and scientist in the Department of Horticulture and Landscape Architecture, Hendrickson and his colleagues are running tests to verify the gene’s function. The research is supported by Pear Bureau Northwest.

Discovery of the ripening gene is important because targeted mutation to help curtail the impulsive Bartlett’s ripening regime (and perhaps coax a bit more flavor from the reserved D’Anjou) is both more precise and quicker than traditional breeding techniques.

“This targeted and hastened crop improvement is expected to have significant impacts for regional pear growers and national pear consumers,” Hendrickson said.

–by Cynthia King, WSU Today

Ag Practices, Policies Can Help Sequester Carbon, WSU Scientist Says

The right combination of agricultural practices and definitive government policies could go a long way toward increasing carbon sequestration on the farm, according to WSU researchers.

Chad Kruger, interim director for WSU’s Center for Sustaining Agriculture and Natural Resources, who coordinated the Climate Friendly Farming Project, says that three basic changes in traditional agricultural practices could dramatically improve farmers’ ability to keep carbon.

“Basically, we’re talking about three things,” Kruger said. “We need to reduce disturbance of the soil, produce more biomass and make sure that biomass and plant residue make it into the soil.”

Kruger said low-till or no-till production minimizes carbon oxidation and erosion – especially important in the dryland farming areas of the Palouse and elsewhere in the state. “We don’t know everything about the fate of carbon in erosion, but we definitely know we’re better off if the soil stays on the hillside.”

That isn’t the only factor in carbon sequestration, though.

“The most important factor is getting more carbon into the soil,” Kruger said.

One way is to make sure that the plant residue from current crops stays in the field, he said. “Field burning, tillage that oxidizes carbon, baling of residue — all reduce the available carbon inputs.”

Another way to increase carbon in the soil is to increase the amount of biomass produced. “Farmers are thinking differently about the types of crops we can grow,” Kruger said. “Our dryland options are limited by rainfall, but in an irrigated system we have a lot of options.”

One of those options is cover cropping, which entails growing a “sacrifice” crop that will be mowed or tilled in, which in turn provides longer-term carbon storage. Kruger offers one caveat to that option — increasing carbon input might also increase nitrogen, and nitrous oxide, in the system. Nitrogen management is an environmental issue facing many growers.

Another option is to bring organically based amendments to the soil. “We need to look beyond traditional amendments such as manure,” Kruger said. “We need to look at compost, paper, municipal solid waste and biochar to increase carbon sequestration. The possibilities are really wide open, and not a lot of research has been done yet.”

Understanding Carbon Markets Workshop

Kruger is a featured speaker at the “Understanding Carbon Markets” workshop being held at Malo, Wash., on April 24. That workshop is being sponsored by WSU Ferry County Extension, Ferry County Commissioners and the Malo Grange.

The complexities of emerging carbon markets for farmers, ranchers and forest owners will be the focus of an April 24 workshop offered by WSU Ferry County Extension, the Ferry County Commissioners and the Malo Grange.

“The buzz about carbon sequestration, greenhouse gas emissions and carbon markets is growing louder, but often lacks clarity,” said Emily Burt, Extension educator in Ferry County. “This workshop will help give landowners and managers an opportunity to learn about the realities of emerging carbon markets, and how carbon sequestration and greenhouse gas emissions relate to their property.”

Presenters at the workshop will cover a variety of topics, including how to keep carbon on the farm, rangeland or forest to reduce the emission of greenhouse gases as well as the economics of carbon market policies such as cap and trade carbon credits. One session, “Selling Carbon Credits from Your Forest, A Real World Example,” will feature the experiences of a real landowner in marketing and selling carbon credits.