Agriculture scientist Dr Matthew Cock, chief scientist for Cabi, a UK-based agri-environment research organisation, lists some of the biggest biological threats to global food security.
Pests like desert locust, western corn root worm (Diabrotica virgifera virgifera), the Khapra beetle (Trogoderma granarium), mountain pine beetle (Dendroctonus ponderosae) and colorado potato beetle (Leptinotarsa decemlineata) are suggested together with plant diseases, causing famine in the past: potato blight (Phytophthora infestans), or big economic losses in agricultural production: wheat stem rust strain Ug99 (Puccinia graminis tritici), South American rubber blight (Microcyclus ulei) and cofee wilt disease (Fusarium xylarioides).
CLEWISTON, Fla. — The call Ricke Kress and every other citrus grower in Florida dreaded came while he was driving. “It’s here” was all his grove manager needed to say to force him over to the side of the road. The disease that sours oranges and leaves them half green, already ravaging citrus crops across the world, had reached the state’s storied groves. Mr. Kress, the president of Southern Gardens Citrus, in charge of two and a half million orange trees and a factory that squeezes juice for Tropicana and Florida’s Natural, sat in silence for several long moments. “O.K.,” he said finally on that fall day in 2005, “let’s make a plan.” In the years that followed, he and the 8,000 other Florida growers who supply most of the nation’s orange juice poured everything they had into fighting the disease they call citrus greening. To slow the spread of the bacterium that causes the scourge, they chopped down hundreds of thousands of infected trees and sprayed an expanding array of pesticides on the winged insect that carries it. But the contagion could not be contained.
They scoured Central Florida’s half-million acres of emerald groves and sent search parties around the world to find a naturally immune tree that could serve as a new progenitor for a crop that has thrived in the state since its arrival, it is said, with Ponce de León. But such a tree did not exist. “In all of cultivated citrus, there is no evidence of immunity,” the plant pathologist heading a National Research Council task force on the disease said. In all of citrus, but perhaps not in all of nature. With a precipitous decline in Florida’s harvest predicted within the decade, the only chance left to save it, Mr. Kress believed, was one that his industry and others had long avoided for fear of consumer rejection. They would have to alter the orange’s DNA — with a gene from a different species.
Ideas about heredity and evolution are undergoing a revolutionary change. New findings in molecular biology challenge the gene-centered version of Darwinian theory according to which adaptation occurs only through natural selection of chance DNA variations. In Evolution in Four Dimensions, Eva Jablonka and Marion Lamb argue that there is more to heredity than genes. They trace four "dimensions" in evolution—four inheritance systems that play a role in evolution: genetic, epigenetic (or non-DNA cellular transmission of traits), behavioral, and symbolic (transmission through language and other forms of symbolic communication). These systems, they argue, can all provide variations on which natural selection can act. Evolution in Four Dimensions offers a richer, more complex view of evolution than the gene-based, one-dimensional view held by many today. The new synthesis advanced by Jablonka and Lamb makes clear that induced and acquired changes also play a role in evolution.
Cellular epigenetic inheritance is explained by many cases from plant, animal and other organisms' world. Eva Jablonka and Marion Lamb argue that there is more to heredity than genes. What determines an organism are “five mothers”: the provider of DNA resources, the provider of non-DNA part of the egg (nuclear and cytoplasmatic), the provider of early nourishment (womb & milk), the provider of home and care and the provider of social education. After this lecture one can start understanding heredity and evolution on different way, as well as how stress and food can influence generations.
To provide molecular and biochemical information on metabolic pathways in potato (Solanum tuberosum), Arabidopsis signaling pathways, and drought response pathways.
A web site designed to provide links to information on metabolic pathways in potato (Solanum tuberosum) including disease resistance, drought responses (to Dicots and Monocots), Arabidopsis signaling etc
In recent years, multipronged research efforts have brought a new level of understanding about this pathogen's complex biology and disease mechanisms, leading to better management strategies. The key papers presented below, published in Phytopathology, Plant Disease, and Molecular Plant-Microbe Interactions, tell a story of progress. Free access is available to these papers for a limited time.
George W. Sundin, Editor-in-Chief, Phytopathology:
The bacterial plant pathogen Xylella fastidiosa is the causal agent of Pierce’s disease of grapevine, citrus variegated chlorosis, leaf scorch disease of almond and other tree hosts, and phony peach disease. This gram-negative bacterium dwells in the xylem of plants and is transmitted between hosts by xylem-feeding insects. The global X. fastidiosa research community is actively studying a variety of topics, including pathogen virulence, plant host resistance, factors influencing bacterial proliferation in xylem, insect interactions, rapid detection, and population genetics. Researchers are also taking many different approaches in attempts to manage diseases caused by X. fastidiosa.
Phytoplasmas are bacteria without cell walls from the class Mollicutes. They are obligate intracellular plant pathogens which cause diseases in hundreds of economically important plants including the grapevine (Vitis vinifera).
This study revealed some fundamental aspects of grapevine interactions with the stolbur 'Bois noir' phytoplasma in particular and some plant interactions with phytoplasmas in general. In addition, the results of the study will likely have an impact on grape improvement by yielding marker genes that can be used in new diagnostic assays for phytoplasmas or by identifying candidate genes that contribute to the improved properties of grape.
By: Hren M, Nikolić P, Rotter A, Blejec A, Terrier, Ravnikar M, Dermastia M, Gruden K; BMC Genomics 2009, 10:460 doi:10.1186/1471-2164-10-460
The Panel on Plant Health conducted a pest risk assessment for Chrysanthemum stunt viroid (CSVd) and identified and evaluated risk reduction options, particularly those listed in Council Directive 2000/29/EC.
"For vegetatively propagated species, in the absence of an efficient certification system, long-distance spread is very likely and a major impact would be expected on chrysanthemum, with associated yield and quality losses. However, under the existing certification scheme for chrysanthemum plant propagation material, the probability of spread through infected cuttings is largely reduced and the direct consequences of viroid outbreaks are expected to be minor. Minimal impact is predicted for other ornamental hosts and a minor impact for solanaceous vegetable crops."
The hands-on 4-day qPCR Experience workshop: Real-time PCR in Plant pathology: Diagnostics and Reseach will focus on diagnostics and quantification of plant pathogenic microorganisms using real-time PCR integrating EPPO Guidelines.
Prior to 2007, late blight was not reported as a serious threat to tomato cultivation in India although the disease has been known on potato since 1953.
In 2009 and 2010, severe late blight epidemics were observed in Karnataka state of India, causing crop losses up to 100%. The phenotypic and genotypic characters of isolates examined in this study were found to be similar to that of 13_A2 genotype of P. infestans population reported in Europe. Thus, appearance of new population similar to 13_A2 genotype was responsible for severe late blight epidemics on tomato in South-West India.
Plants can sometimes exhibit human-like behavior — some respond to music, smell other plants or seem to shrink away when touched. In fact, some would argue that greenery is sensitive enough to deserve rights.
CHANNELSScientists develops new Nigerian cassavaCHANNELSPlant scientists at a Swiss science and technology university, ETH Zurich have developed a new Nigerian cassava preferred by consumers and farmers that is resistant to the two major virus diseases...
Australian Government offers PaDIL - a biodiversity and biosecurity information management system with delivering high quality diagnostic images. The infrastructure allows users to query datasets and to manage image database libraries. Use of the content is subject to terms and conditions.
The second example of storing digital data in DNA affirms its potential as a long-term storage medium.
Researchers have done it again—encoding 5.2 million bits of digital data in strings of DNA and demonstrating the feasibility of using DNA as a long-term, data-dense storage medium for massive amounts of information. In the new study released today (January 23) in Nature, researchers encoded one color photograph, 26 seconds of Martin Luther King Jr.’s “I Have a Dream” speech, and all 154 of Shakespeare’s known sonnets into DNA.
The researchers calculated that 1 gram of DNA could hold more than 2 million megabytes of information, though encoding information on this scale will involve reducing the synthesis error rate even further.
The original article is not brand new, but it is worth mentioning: N. Goldman et al., “Towards practical, high-capacity, low-maintenance information storage in synthesized DNA,” Nature, doi: 10.1038/nature.11875, 2013.
This revolutionary experiment could develop into a new option for archival data storage, wherein DNA is not thought of as a biological molecule, but as a straightforward non-living data storage medium...
Adapting a novel form of insect resistance discovered in a wild plant native to Peru, Mutschler-Chu, professor of plant breeding and genetics, first isolated the resistance. She found that it was mediated by droplets of sugar ...
Thrips are tiny insects that pierce and suck fluids from hundreds of species of plants, including tomatoes, grapes, strawberries and soybeans.
They also transmit such diseases as the tomato spotted wilt virus, causing millions of dollars in damage to U.S. agricultural crops each year.
The Cornell thrips-resistant tomato lines, with and without the virus resistance genes, will be used by Mutschler-Chu and an interdisciplinary team of eight other scientists from seven other institutions nationwide as part of a new five-year, $3.75 million project to control thrips and TOSPO viruses in tomatoes.
Maize Lethal Necrosis disease, which was first reported in Kenya and Tanzania, has now spread to Uganda, raising concerns for food security in the country.
Maize Lethal Necrosis disease was first observed in 2011 and 2012 in the Rift Valley Province in Kenya. Scientists identified the disease to be caused by a double infection of the maize chlorotic mottle virus and the sugarcane mosaic virus.
When you look out on a golden-yellow field of oilseed rape you might not think you're seeing a battleground, but crops including oilseed rape, wheat, potato and tomato are engaged in a constant fight with pests and disease, trying to stay one step ahead.
As the world's human population looks set to increase to nine billion people by 2050, keeping plants healthy and productive is going to be essential to making sure there is enough food to go round.Aphids damage crops by feeding on them and transmitting plant diseases. "Crop pests are emerging earlier due to global warming and new variants are arriving from other countries, bringing new plant viruses", said Dr Saskia Hogenhout from the John Innes Centre (JIC) in Norwich, an institute strategically funded by the BBSRC.
Among these pests whitefly and green peach aphids cause hundreds of millions of pounds of damage and loss to crops through transmitting viruses and feeding. Both species are notorious for demonstrating the ability to rapidly develop resistance to conventional pesticides, and both attack a wide variety of crops, including cabbage, lettuce, beet, oilseed rape and potato. In UK cereal crops aphids alone can cause yield losses of over 40 per cent, and insect pests are responsible for an estimated 15 per cent of all crop losses globally. Dr Hogenhout said: "The aphids and whitefly themselves are problematic but they also transmit more than half of all plant viruses. They're called the mosquitoes of plants because like mosquitoes they feed on the vascular system and they transmit quite a number of viruses."
Very promissing non-chemical method to combath aphid and whitefly species in the future! Whiteflies suffer from an identity crisis, as they are not flies at all, in appearance they resemble tiny, pure white 'moths' but are in fact, closely related to sap-sucking aphids. Aphids and whiteflies can both cause severe damage to wide range of crops by sucking sap from the plant, resulting in damages of the leaves, as well as leaf loss, wilting and stunting. Not only do they feed on plants, but they also produce honeydew, which spoils the plants' appearance, attracts ants and black sooty mould. Both can also transmit different species of plant viruses, which cause further damage to crops. Until the gene silencing methods are applied, biologocial control could be used as alternative to insecticide's use.
New species of the year http://t.co/uEGufcLB #opentree #phylo #TOL #evolution #nature #species #nature #biodiversity Taxonomists have described about 1.9 million living species so far (not counting bacteria and archaea). But a recent estimate predicts 6.8 million more to discover. At the current pace, it will take another 400 years to name them all. If a higher estimate is right, the job could take 1,653 years, assuming species don’t go extinct before scientists notice them.
One of the most remarkable was the description of Solanum umtuma, a prickly South African shrub related to eggplant. Anyone about to argue that, say, this year’s dragon millipedes trump a vegetable should read the Solanum paper’s diagnosis section, distinguishing the new species from old ones.
Farmers Guardian. Decline in plant disease expertise is a cause for concern. Plant pathology has been lost completely, or greatly reduced at 11 universities and colleges, while fewer than half of the institutions which teach biology, agriculture or forestry offer courses in plant pathology
Potato Leafroll Virus (PLRV) and Potato Spindle Tuber Viroid (PSTVd) are pathogenes which cause cultivars degeneratation and yield reduction of potato,and spread extensively. Previous researches indicated that the spreading of PLRV by aphids redounded to the propagation of PSTVd. Therefore, it is especially important for potato cultivars to resist PLRV and PSTVd together. An effective and economic method to cultivate virus-resistant potato cultivars could be by plant genetic engineering.
In this research marker-free bivalent expression vector p3301-DR-Isir with RNAi structure of PLRV IS and di-component ribozyme specificly cleaving PSTVd RNA(-)was constructed successfully, which could be used as gene source to transform potato cultivars for high resistances to PLRV and PSTVd.
The Q-bank Phytoplasma database contains DNA sequences (Barcodes) of more than 100 strains that are of relevance to phytoplasma phytopathology.
Q-bank offers descriptions of well characterized regulated plants pests. It comprises ecological, morphological, physiological, and sequence data of items that are available in physical collections of plantpathogenic bacteria, fungi, insects, nematodes, phytoplasmas, viruses and viroids, and invasive plants.
The entries in Q-bank are continuously updated by a team of curators with taxonomic, phytosanitary and diagnostic expertise from world-wide national plant protection organizations and institutes with connections to relevant phytosanitary collections. Where relevant, information is linking to other databases such as European and Mediterranean Plant Protection Organization (EPPO).