Leaf Doctor: UH plant expert launches third app

May 13, 2014 7:26 pm 0 comments

Leaf Doctor 1Fresh from his success with two widely utilized smartphone apps, plant pathologist Scot Nelson has created a new and more technical app, the Leaf Doctor, for a more specialized audience.

Nelson, who works at the College of Tropical Agriculture and Human Resources at the University of Hawaii, doesn’t anticipate that the Leaf Doctor will have the same broad, popular appeal as his Plant Doctor app. For many of those who will use the Leaf Doctor, though, it is likely to be a professional game-changer.

Nelson’s Plant Doctor app helps to identify disease on plants and has been used all over the globe, from Iceland to Indonesia. Likewise, his second app, Pic-a-Papaya, tracks papaya ringspot virus in Hawaii — originally intended only for use in the Honolulu area but has been getting submissions from throughout the Hawaiian Islands.

The Leaf Doctor focuses on the finer points of diagnosing plant diseases. Disease tends to increase over time and space, whether in an individual plant or in a plant population, and researchers need to know how fast and how far it’s increasing. Plant epidemiology includes the assessment of disease in order to make a mathematical model of its progress in time and space.

Being able to accurately quantify disease is necessary for growers looking at different plant varieties for disease resistance, or breeders attempting to introduce increased resistance into a new hybrid. It’s also useful for those advising farmers about when to time certain pest-management strategies, since some forms of management are more effective at certain points in the development of an epidemic.

Currently those who assess plant disease severity use a quite low-tech method that hasn’t changed much in decades: they obtain rough estimates by comparing what they see with printed or online “standard area diagrams.” These standardized drawings—usually not even photographs—depict what different percentages of host coverage of a given disease look like on a particular type of plant.

There is one computer-based plant disease assessment system available, Nelson explains. Only available for PC users, it costs $795 and is difficult to use, not interactive, and not particularly accurate. By contrast, the easy-to-use, interactive app that he has created may be downloaded for free to iPhones and other iOS devices and is accurate to within a percentage point.

Leaf Doctor 2Nelson notes that, while the app was not simple to develop, it is simple to use: The user takes a picture with the iPhone or calls one up from the phone’s gallery, then identifies the coloration of healthy tissue in the photo by touching the screen to identify up to seven healthy areas on the plant to account for natural color variations, light changes, and veins. A slide bar is used is used to mask out everything that is not healthy, which the app identifies as diseased tissue and calculates as a percentage of total leaf area displayed.

Users are then able to email the image and the generated assessment data to themselves or others; they are also able to build specialized and far more accurate standard area diagrams by creating a gallery of images showing a range of percentages of disease. If Nelson is able to secure more funding next year, he hopes to add further analytical functions to the app.

More information may be found about the app at Nelson’s website.

He anticipates that the main users of the app will be plant epidemiologists and breeders, and plant pathology professors and students, not necessarily home gardeners. However, it may have more users than originally assumed, because it is free and fun to use, and its far-ranging applications could be used for quantifying the area in any photograph for skin disease or invasive species.

Leave a Reply


Other News

  • Featured Media Publicity Hawaii Herald launches online edition

    Hawaii Herald launches online edition

    The Hawai‘i Herald today took a major step forward in its more than thirty­ year ­history with the launch of its online edition. The debut issue is focused on the Primary Election, with a story on the “David vs. Goliath” gubernatorial race between incumbent Governor Neil Abercrombie and veteran State Senator David Ige, as well as a Q&A forum on the issues with responding candidates for the major offices.

    “This is an historic moment for The Hawai‘i Herald, the only Hawaii­-based newspaper dedicated to covering the local Japanese American community,” says Keiichi Tagata, president of parent company Hawaii Hochi, Ltd. “After 34 years of sharing stories in print with loyal readers, mostly in Hawaii, we look forward to sharing the Herald with a wider audience of readers around the world.”

    Read more →
  • Featured Technology Honolulu happy hour app taps new beacon tech

    Honolulu happy hour app taps new beacon tech

    Happy Hour Pal, a Honolulu-based startup, is the first business to deploy beacon technology into restaurants and bars throughout the state.

    Happy Hour Pal is a searchable website and free GPS-based mobile app that allows people to save money while dining out, by locating happy hour specials in their area. Integrating beacon technology will make Happy Hour Pal even easier for users to identify nearby happy hour specials, and provide local businesses an effortless opportunity to engage directly with customers and increase awareness and sales during the most powerful internal promotion – happy hour.

    Happy Hour Pal’s website and mobile app users can search for happy hour specials by food, drink, time, and location, and easily access happy hour menus and daily specials for each business. Users can share information via text message and email, and invite friends to join them for happy hour. Users can also earn points for rewards when they check in to a business on the app.

    Read more →
  • Featured Publicity Science Third historic volcano found off O‘ahu

    Third historic volcano found off O‘ahu

    University of Hawaii researchers, working with colleagues in California and France, have discovered evidence of a third major shield volcano making up the island of O‘ahu.

    Previously, geologists believed the island’s current profile is the remnants of two volcanoes, Wai‘anae and Ko‘olau. But extending almost 100 km WNW from Ka‘ena Point, the western tip of the island of O‘ahu, is a large region of shallow bathymetry, called the submarine Ka‘ena Ridge. It is that region that has now been recognized to represent a precursor volcano to the island of O‘ahu, and on whose flanks the Wai‘anae and Ko‘olau Volcanoes later formed.

    The team included scientists from the University of Hawai‘i–Mānoa, Laboratoire des Sciences du Climat et de L’Environment in France, and Monterey Bay Aquarium Research Institute.

    Read more →
  • Education Featured Publicity Science Technology Leaf Doctor: UH plant expert launches third app

    Leaf Doctor: UH plant expert launches third app

    Fresh from his success with two widely utilized smartphone apps, plant pathologist Scot Nelson has created a new and more technical app, the Leaf Doctor, for a more specialized audience.

    Nelson, who works at the College of Tropical Agriculture and Human Resources at the University of Hawaii, doesn’t anticipate that the Leaf Doctor will have the same broad, popular appeal as his Plant Doctor app. For many of those who will use the Leaf Doctor, though, it is likely to be a professional game-changer.

    The Leaf Doctor focuses on the finer points of diagnosing plant diseases.

    Read more →
  • Featured Health Publicity Study: Shorter men may live longer

    Study: Shorter men may live longer

    Short height and long life have a direct connection in Japanese men, according to new research based on the Kuakini Honolulu Heart Program (HHP) and the Kuakini Honolulu-Asia Aging Study (HAAS).

    “We split people into two groups – those who were 5-foot-2 and shorter, and 5-4 and taller,” said Dr. Bradley Willcox, one of the investigators for the study and a UH Mānoa Professor at the John A. Burns School of Medicine’s (JABSOM’s) Department of Geriatric Medicine. “The folks that were 5-2 and shorter lived the longest. The range was seen all the way across from being 5-foot tall to 6-foot tall. The taller you got, the shorter you lived.”

    Researchers at the Kuakini Medical Center, JABSOM and U.S. Veterans Affairs worked on the study, which was recently published in PLOS ONE, a peer-reviewed medical journal.

    The researchers showed that shorter men were more likely to have a protective form of the longevity gene, FOXO3, leading to smaller body size during early development and a longer lifespan. Shorter men were also more likely to have lower blood insulin levels and less cancer.

    Read more →
  • Featured Science Deep origins to the behavior of our volcanoes

    Deep origins to the behavior of our volcanoes

    Kīlauea volcano, on the Big Island of Hawaii, typically has effusive eruptions, where magma flows to create ropy pāhoehoe lava. But Kīlauea sometimes erupts more violently, showering scoria and blocks over much of the surface of the island. To explain the variability in Kīlauea’s eruption styles, a research team analyzed 25 eruptions that have taken place over the past 600 years.

    Their research shows that the ultimate fate of a magma at Kīlauea — that is if the eruption will be effusive or explosive — is strongly influenced by the variability in composition of the deep magma. In short, more gas-rich magmas produces more explosive eruptions.

    “Gas-rich magmas are ‘predisposed’ to rise quickly through the Earth’s mantle and crust and erupt powerfully,” Houghton explained.

    Read more →
  • Education Environment Featured Transportation Bike Commuting Celebrated on Thursday

    Bike Commuting Celebrated on Thursday

    This year’s “BikeUHM,” the annual appreciation and promotional event for those who cycle and who are thinking of cycling to UH Mānoa, coincides with the University’s Earth Day Festival on Thursday, April 24. “BikeUHM 2014: Earth Cycles” will be held along Legacy Path (near Dole Street) from 8:00 to 10:00 a.m.

    To further enhance the cycling experience at UH Mānoa, the University has implemented Sharrow lanes (shared by both motorists and bicyclists) and free bike parking in any of the more than 150 racks positioned around campus. Coming soon is the installation of a secure, enclosed bike shelter in the Lower Campus Parking Structure and bike-share stations on campus, as recommended in a recent feasibility study for bike-sharing in Honolulu.

    Read more →
  • Education Publicity Winners named in school attendance video contest

    Winners named in school attendance video contest

    Winners of a video contest to discourage school truancy were announced yesterday. The “Be Pono – Be in School” video contest was organized by schools on the Windward side of Oahu. Judges awarded prizes valued at $10,000. More than 1,500 students – some in kindergarten – created and produced a total of 60 video entries. Described as the state’s first district-wide attendance-campaign video contest, it launched last month and drew participation by one-third of all Windward District schools. Entrants submitted 30-second spots […]

    Read more →