Is Imprelis herbicide killing your trees?

The NYTimes is reporting that several tree deaths are being linked to the use of the new herbicide Imprelis.

Imprelis uses pyrimidine carboxylic acid (trade name Aptexor )
A recently approved herbicide called Imprelis, widely used by landscapers because it was thought to be environmentally friendly, has emerged as the leading suspect in the deaths of thousands of Norway spruce, eastern white pine and other trees on lawns and golf courses across the country.

Manufactured by DuPont and approved for sale last October by the federal Environmental Protection Agency, Imprelis is used for killing broadleaf weeds like dandelion and clover and is sold to lawn care professionals only. Reports of dying trees started surfacing around Memorial Day, prompting an inquiry by DuPont scientists.

Read more at the NYTimes Story on Imprelis

There have been several reports from both outside and within the state of Michigan of herbicide injury on Norway spruce and white pine following application of the turfgrass herbicide Imprelis (a.i. aminocyclopyrachlor). Damaged trees have symptoms consistent with growth regulator type herbicides. Injury includes curling and twisting of new growth. Pictures and comments of damage observed in Indiana can be viewed at Purdue Extension’s Plant and Pest Diagnostic Laboratory website.

Read more at the Michigan State Extension Office

DuPont is looking into this and recommends that you do not use Imprelis near spruces or white pines for now.

How much fertilizer do transplants need?

In hot humid climates nitrogen is always in short supply. If you, like me, also use pine mark or other mulches that break down rapidly there is even less nitrogen in the soil.

The plants you bring home to your landscape come from a well fed environment. To help them adjust keep up the fertilizer levels for the first six months. Two years later your plants will be stronger and healthier.

If you just use nitrogen as we often do down here the new plants may develop potassium and magnesium deficiencies. So be sure to use a good all around fertilizer.


The roots of container-grown ornamental plants primarily are concentrated within the original container substrate root ball during the establishment period following transplanting into the landscape. Plants growing in container substrates containing pine bark or peatmoss have higher nitrogen (N) requirements than in most landscape soils due to microbial immobilization of N by these organic components. However, use of high-N fertilizers, such as those used in container production of ornamentals, can cause imbalances with potassium (K) and magnesium (Mg) when used on palms in sandy landscape soils. Areca palm (Dypsis lutescens) and chinese hibiscus (Hibiscus rosa-sinensis ‘President’) that had been growing in containers were transplanted into a landscape soil to determine if high N fertilization during the establishment period could accelerate the rate of establishment without exacerbating K and Mg deficiencies. Although plants of both species had the darkest green color and largest size when continuously fertilized with high N fertilizer, this treatment did induce Mg deficiency in both species. Plant size and color for both species were highly correlated with cumulative N application rates, but also with initial N application rates, suggesting that high N fertilization during the first 6 months affected plant quality at 12 and 24 months after planting, even if high N fertilization was discontinued. However, continued use of a moderate N landscape palm maintenance fertilizer ultimately produced areca palm plants as good as those receiving high N during the establishment period.

Effects of Fertilization on the Growth and Quality of Container-grown Areca Palm and Chinese Hibiscus during Establishment in the Landscape

Sudden oak death

I’ve lost two oaks to Oak Wilt. Now we may loose more of our oaks to a new threat spreading across from the west coast.

It’s not just oak that are effected, bay laurels, rhododendron and viburnum are also susceptible.

In sudden oak death the leaves at the top die first, canker appear leaking reddish sap, then beetles attack the tree.

Sudden oak death and Phytophthora ramorum, both first recognized about a decade ago, have been the subject of hundreds of scientific and popular press articles. This document presents a comprehensive, concise summary of sudden oak death and P. ramorum research findings and management activities. Topics covered include introduction and background, identification and distribution, the disease cycle, epidemiology and modeling, management and control, and economic and environmental impacts. Sudden oak death and Phytophthora ramorum

Sudden oak death: A threat to Texas Forests

Check plants before you bring them home from the nursery and remove and destroy effected plants.

New plant hormone discovered that can help plants through stressful times

The discovery of a hormone acting like molecular glue could hold a key to bolstering plant immune systems and understanding how plants cope with environmental stress.

The study, which is featured in the Oct. 6 issue of Nature, reveals how the plant hormone jasmonate binds two proteins together — an emerging new concept in hormone biology and protein chemistry. The study also identifies the receptor’s crystal structure to provide the first molecular view of how plants ward off attacks by insects and pathogens.

In short, the work explains how a highly dynamic form of plant immunity is triggered, said Gregg Howe, biochemistry and molecular biology professor, who worked with fellow MSU professor Sheng Yang He on the study. The study is a collaboration between the MSU-Department of Energy Plant Research Laboratory and the University of Washington.

“In many respects, this receptor is novel in how it binds its target hormone to switch on gene expression,” Howe said. “Jasmonate appears to act as molecular glue that sticks two proteins together, which sets off a chain of events leading to the immune response. Determining the structure of the receptor solves a big missing piece of the puzzle.” read more

Jasmonate perception by inositol-phosphate-potentiated COI1–JAZ co-receptor

New spray may protect plants from drought

New VARI Findings Next Step to Growing Drought-Resistant Plants
September 28, 2010

Study could help produce alternative to genetically-engineered crops to combat global food shortages

Grand Rapids, Mich. (September 28, 2010) – New findings from Van Andel Research Institute (VARI) scientists could lead to environmentally-friendly sprays that help plants survive drought and other stresses in harsh environments to combat global food shortages. The study is a follow-up to findings published in Nature last year that were named among the top breakthroughs of 2009 by Science magazine.

“I think that the work established the methodologies and feasibilities of finding cheap and environmentally benign chemicals for agricultural application to improve the water use efficiency and drought tolerance of crops,” said Jian-Kang Zhu, Professor of Botany and Presidential Chair of Botany & Plant Sciences at the University of California, Riverside. “The work also provides a better understanding of ABA receptor function, which will help efforts in the genetic engineering of hardier crops.”

In a 2009 study published in Nature, VARI scientists determined precisely how the plant hormone abscisic acid (ABA) works at the molecular level to help plants respond to environmental stresses such as drought and cold. These findings could help engineer crops that thrive in harsh environments.

One of ABA’s effects is to cause plant pores to close when plants are stressed so that they can retain water. In the new study, researchers identified several synthetic compounds that fit well with ABA’s many receptors, or cellular “docking stations,” to have the same effect. By finding compounds that can close these pores, researchers’ findings could lead to sprays that use a plant’s natural defenses to help it survive harsh environmental conditions.

“Sprays would allow plants to be much more adaptable than if we genetically engineered them,” said Karsten Melcher, Ph.D., one of the lead authors of the study and research scientist in the VARI Laboratory of Structural Biology led by Distinguished Scientific Investigator H. Eric Xu. “You could spray plants to close the pores only when drought or other harsh conditions threaten the plant.”

The lab originally began studying ABA because a proposed ABA receptor was reported to be a member of a group of proteins that the lab studies, which are targeted by more than 50% of all drugs on the market. It was later found that the receptor was not part of this group of proteins, but Xu’s lab continued its’ studies.

The findings appear in Nature Structural & Molecular Biology alongside a companion paper from authors Francis C. Peterson (first author), Brian Volkman, Davin R. Jensen, and Joshua J. Weiner from the Medical College of Wisconsin, Sean Cutler, Sang-Youl Park and Chia-An Chang from University of California, Riverside (UCR), and Sethe Burgie, Craig A. Bingman, and George Phillips, Jr., from the University of Wisconsin-Madison. A third parallel study has also been reported by Dr. Nieng Yan’s group in the Journal of Biological Chemistry.

“Last year Dr. Xu and his lab offered the plant community the long-awaited key to creating drought-resistant crops,” said VARI President and Research Director Dr. Jeffrey Trent. “Only a few short months later, and they already have taken huge strides further toward the ultimate goal of helping combat world hunger.”

Information
source

Use detergent to keep botrytis from roses

A major pathogen in roses, the mould Botrytis cinerea, can be easily kept at bay with a dash of chlorine. Wageningen researchers discovered this by chance.

Botrytis causes big problems in rose cultivation. Every rose is infected by botrytis spores which have to be killed before transportation by ship or aeroplane to the consumer. Since the mould develops resistance to herbicides quickly, growers have come up with complex spray schedules using four or five substances to kill the mould.

Control substance turns out to be answer
Things can be much simpler, American and Wageningen researchers reveal this month in the journal Postharvest Biology and Technology. Ernst Woltering and American colleagues from UC Davis compared commercial substances for getting rid of botrytis in the laboratory. During the test, the researchers used a chlorine solution as the control substance. To their surprise, chlorine worked better than the other substances. A litre of water with a small dash of Glorix (one or two millilitres of household detergent) is all it takes, says Woltering. The chlorine kills the spores of the mould. ‘If the plant is already infected by the mould, chlorine is useless.’

No patent
Woltering has in the meantime tested the use of chlorine in batches of roses transported in containers on ships. The use of chlorine has resulted in fifty to seventy percent less damage by botrytis. Moreover, the damage in affected roses is less severe, Woltering concludes from this study.

The researchers have discovered the positive effects of chlorine already two years ago, but wanted first to find out if they can apply for a patent for their discovery. ‘But the answer is so terribly simple that it cannot be patented’, says Woltering. ‘Anyone can buy chlorine solution. The discovery cannot be protected. We have therefore decided to publish the outcome.’ / Albert Sikkema

Cocao Plant has its genes sequenced

Recently the chocolate market was cornered ( Trader’s Cocoa Binge Wraps Up Chocolate Market ) Good fortune held and the price of cocoa fell instead of rising and leaving us all the mercy of this villain.

And now thanks to the US Dept of Agriculture other threats against cocoa will be easier to solve.


WASHINGTON, D.C. — U.S. Department of Agriculture (USDA) scientists and their partners have announced the preliminary release of the sequenced genome of the cacao tree, an achievement that will help sustain the supply of high-quality cocoa to the $17 billion U.S. chocolate industry and protect the livelihoods of small farmers around the world by speeding up development, through traditional breeding techniques, of trees better equipped to resist the droughts, diseases and pests that threaten this vital agricultural crop.

Cocoa comes from the cacao tree, Theobroma cacao. The tree seeds are processed into cocoa beans that are the source of cocoa, cocoa butter and chocolate. But fungal diseases can destroy seed-bearing pods and wipe out up to 80 percent of the crop, and cause an estimated $700 million in losses each year.

Worldwide demand for cacao now exceeds production, and hundreds of thousands of small farmers and landholders throughout the tropics depend on cacao for their livelihoods. An estimated 70 percent of the world’s cocoa is produced in West Africa.

Scientists worldwide have been searching for years for ways to produce cacao trees that can resist evolving pests and diseases, tolerate droughts and produce higher yields. ARS researchers have been testing new cacao tree varieties developed with genetic markers. But having the genome sequenced is expected to speed up the process of identifying genetic markers for specific genes that confer beneficial traits, enabling breeders to produce superior new lines through traditional breeding techniques.

Sequencing cacao’s genome also will help researchers develop an overall picture of the plant’s genetic makeup, uncover the relationships between genes and traits, and broaden scientific understanding of how the interplay of genetics and the environment determines a plant’s health and viability.

The genome sequence will be released into the public domain, with access to these data online via the Cacao Genome Database (www.cacaogenomedb.org) prior to formal peer-reviewed publication. This release will enable the sequence data to be applied immediately to cacao genetic improvement.

The research team will continue to improve the quality and analyze the properties of the cacao genome sequence in preparation for publication in a peer-reviewed journal. ( Source )