Protein Biomarkers: Identify Disease-Carrying Aphids

Aphids can transmit viruses that cause crop diseases and reduce the quality and quantity of fresh foods. Spraying insecticides can control aphids and reduce the spread of viruses, but spraying is expensive and can harm the environment. Additionally, not all aphids transmit viruses. So a key question for growers is knowing when and what to spray to control viral diseases. Agricultural Research Service scientists Michelle Cilia and Stewart Gray, in the Biological Integrated Pest Management Unit at the Robert W. Holley Center for Agriculture and Health in Ithaca, New York, have found a way to distinguish aphids that spread viruses from those that don’t—by studying the aphid’s proteins

New Tool Opens a Bigger Window to Insect-Plant Warfare

When an aphid, leafhopper, or psyllid lands on a plant to feed, it begins a process of chamical welfare. As piercing-sucking insects, they use needlelike stylets to insert saliva into plant tissues and open a pathway to ingest fluids critical to the plant’s survival. When punctured, the plant senses the attack and secretes proteins and other chemical defenses to prevent fluids from being pulled out, thus creating a stress on the plant. This warfare costs growers billions of dollars each year in lost ornamentals, vegetables, citrus, and other important agricultural crops. Because much of the action takes place in the plant’s interior, a scientific tool called an “electrical penetration graph” (EPG) is critical for peering into the process. To use it, researchers connect the insect and plant to an electronic monitor that, like an electrocardiogram, reads electrical charges produced by tiny changes in voltage that occur as the insect feeds. A new type of EPG, developed by Elaine Backus, an ARS entomologist at the San Joaquin Valley Agricultural Sciences Center, in Parlier, California, and the late William Bennett, formerly from the University of Missouri, is giving scientists the clearest window yet into the wars waged between piercing sucking insects and the plants they infest. Because these insects are often carriers of plant pathogens that are transmitted through feeding, EPG can also illuminate how pathogens are injected into the plant to start the infection process

New Tool Opens a Bigger Window to Insect-Plant Warfare

When an aphid, leafhopper, or psyllid lands on a plant to feed, it begins a process of chamical welfare. As piercing-sucking insects, they use needlelike stylets to insert saliva into plant tissues and open a pathway to ingest fluids critical to the plant’s survival. When punctured, the plant senses the attack and secretes proteins and other chemical defenses to prevent fluids from being pulled out, thus creating a stress on the plant. This warfare costs growers billions of dollars each year in lost ornamentals, vegetables, citrus, and other important agricultural crops. Because much of the action takes place in the plant’s interior, a scientific tool called an “electrical penetration graph” (EPG) is critical for peering into the process. To use it, researchers connect the insect and plant to an electronic monitor that, like an electrocardiogram, reads electrical charges produced by tiny changes in voltage that occur as the insect feeds. A new type of EPG, developed by Elaine Backus, an ARS entomologist at the San Joaquin Valley Agricultural Sciences Center, in Parlier, California, and the late William Bennett, formerly from the University of Missouri, is giving scientists the clearest window yet into the wars waged between piercing sucking insects and the plants they infest. Because these insects are often carriers of plant pathogens that are transmitted through feeding, EPG can also illuminate how pathogens are injected into the plant to start the infection process

An Atlas for Guatemala, a Tool for Conserving World Crops

With exotic names like ayote de caballo (a wild squash), friajolito (a wild bean), and teocinte (a wild relative of corn), Guatemala’s native plants seem very different from the agricultural bounty produced by farmers in the United States and other countries. But many of these native plants carry genes that may be vital to global food security. A new tool, developed by a team that includes Agricultural Research Service scientists, will make it easier to find and preserve these important plants. The tool is an interactive atlas designed to provide Guatemalan scientists and land managers with information on where these crop wild relatives grow, where they are relatively safe from habitat destruction, and which ones are rare and most at risk. The genes these wild plants contain may prove useful in addressing threats posed by emerging diseases, insect pests, and temperature and rainfall extremes arising from a changing climate, says Karen Williams, a botanist with the ARS National Germplasm Resources Laboratory in Beltsville. “Guatemala has many genetically diverse native plants closely related to some of our most important crops, including corn, beans, peppers, and potatoes. Some of these crop wild relatives are found only in Guatemala, and they have genes that equip them with survival mechanisms that may be useful to protect crops,” Williams says. Williams worked on the atlas for almost 10 years with César Azurdia Pérez from the Agronomy Faculty at the University of San Carlos in Guatemala, David E. Williams and Veerle van Damme from Bioversity International, and Andrew Jarvis and Silvia Elena Castaño from the International Center for Tropical Agriculture

Sleep-Disordered Breathing Affects Auditory Processing in 5–7 Year-Old Children: Evidence From Brain Recordings

Poor sleep in children is associated with lower neurocognitive functioning and increased maladaptive behaviors. The current study examined the impact of snoring (the most common manifestation of sleep-disordered breathing) on cognitive and brain functioning in a sample of 35 asymptomatic children ages 5–7 years identified in the community as having habitual snoring (SDB). All participants completed polysomnographic, neurocognitive (NEPSY) and psychophysiological (ERPs to speech sounds) assessments. The results indicated that sub-clinical levels of SDB may not necessarily lead to reduced performance on standardized behavioral measures of attention and memory. However, brain indices of speech perception and discrimination (N1/P2) are sensitive to individual differences in the quality of sleep. We postulate that addition of ERPs to the standard clinical measures of sleep problems could lead to early identification of children who may be more cognitively vulnerable because of chronic sleep disturbances

“Catch 22”: biosecurity awareness, interpretation and practice amongst poultry catchers

Campylobacter contamination of chicken on sale in the UK remains at high levels and has a substantial public health impact. This has prompted the application of many interventions in the supply chain, including enhanced biosecurity measures on-farm. Catching and thinning are acknowledged as threats to the maintenance of good biosecurity, yet the people employed to undertake this critical work (i.e. ‘catchers’) are a rarely studied group. This study uses a mixed methods approach to investigate catchers’ (n = 53) understanding of the biosecurity threats posed by the catching and thinning, and the barriers to good biosecurity practice. It interrogated the role of training in both the awareness and practice of good biosecurity. Awareness of lapses in biosecurity was assessed using a Watch-&-Click hazard awareness survey (n = 53). Qualitative interviews (n = 49 catchers, 5 farm managers) explored the understanding, experience and practice of catching and biosecurity. All of the catchers who took part in the Watch-&-Click study identified at least one of the biosecurity threats with 40% detecting all of the hazards. Those who had undergone training were significantly more likely to identify specific biosecurity threats and have a higher awareness score overall (48% compared to 9%, p = 0.03). Crucially, the individual and group interviews revealed the tensions between the high levels of biosecurity awareness evident from the survey and the reality of the routine practice of catching and thinning. Time pressures and a lack of equipment rather than a lack of knowledge appear a more fundamental cause of catcher-related biosecurity lapses. Our results reveal that catchers find themselves in a ‘catch-22′ situation in which mutually conflicting circumstances prevent simultaneous completion of their job and compliance with biosecurity standards

Garden varieties: how attractive are recommended garden plants to butterflies?

One way the public can engage in insect conservation is through wildlife gardening, including the growing of insect-friendly flowers as sources of nectar. However, plant varieties differ in the types of insects they attract. To determine which garden plants attracted which butterflies, we counted butterflies nectaring on 11 varieties of summer-flowering garden plants in a rural garden in East Sussex, UK. These plants were all from a list of 100 varieties considered attractive to British butterflies, and included the five varieties specifically listed by the UK charity Butterfly Conservation as best for summer nectar. A total of 2659 flower visits from 14 butterfly and one moth species were observed. We performed a principal components analysis which showed contrasting patterns between the species attracted to Origanum vulgare and Buddleia davidii. The “butterfly bush” Buddleia attracted many nymphalines, such as the peacock, Inachis io, but very few satyrines such as the gatekeeper, Pyronia tithonus, which mostly visited Origanum. Eupatorium cannibinum had the highest Simpson’s Diversity score of 0.75, while Buddleia and Origanum were lower, scoring 0.66 and 0.50 respectively. No one plant was good at attracting all observed butterfly species, as each attracted only a subset of the butterfly community. We conclude that to create a butterfly-friendly garden, a variety of plant species are required as nectar sources for butterflies. Furthermore, garden plant recommendations can probably benefit from being more precise as to the species of butterfly they attract

A Real-Time Capable Software-Defined Receiver Using GPU for Adaptive Anti-Jam GPS Sensors

Due to their weak received signal power, Global Positioning System (GPS) signals are vulnerable to radio frequency interference. Adaptive beam and null steering of the gain pattern of a GPS antenna array can significantly increase the resistance of GPS sensors to signal interference and jamming. Since adaptive array processing requires intensive computational power, beamsteering GPS receivers were usually implemented using hardware such as field-programmable gate arrays (FPGAs). However, a software implementation using general-purpose processors is much more desirable because of its flexibility and cost effectiveness. This paper presents a GPS software-defined radio (SDR) with adaptive beamsteering capability for anti-jam applications. The GPS SDR design is based on an optimized desktop parallel processing architecture using a quad-core Central Processing Unit (CPU) coupled with a new generation Graphics Processing Unit (GPU) having massively parallel processors. This GPS SDR demonstrates sufficient computational capability to support a four-element antenna array and future GPS L5 signal processing in real time. After providing the details of our design and optimization schemes for future GPU-based GPS SDR developments, the jamming resistance of our GPS SDR under synthetic wideband jamming is presented. Since the GPS SDR uses commercial-off-the-shelf hardware and processors, it can be easily adopted in civil GPS applications requiring anti-jam capabilities