Featured Research

from universities, journals, and other organizations

Study Of Raindrop Energy To Aid Fight Against Crop Diseases

Date:
December 2, 1998
Source:
Ohio State University
Summary:
A sensor that measures the kinetic energy of falling raindrops may one day warn farmers about outbreaks of crop diseases, according to researchers at Ohio State University.

COLUMBUS, Ohio -- A sensor that measures the kinetic energy of falling raindrops may one day warn farmers about outbreaks of crop diseases, according to researchers at Ohio State University.

Laurence Madden, a professor of plant pathology, and his students at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio, are field-testing a commercial sensor they helped develop to measure the energy of raindrops.

Early results show that the sensor could help explain how rain spreads the fungal spores that cause some crop diseases. One day, weather stations in disease-prone areas may be able to use the sensor to forecast possible outbreaks. This work appeared in a recent issue of the journal Phytopathology.

Madden said that farmers have no way of knowing whether a particular rain shower is the kind that will spread water-borne plant pathogens such as disease-causing fungi.

“With no forecast system to warn of outbreaks, growers have to spray anti-fungal pesticides regularly just to play it safe,so they waste a lot of pesticide,” said Madden. “If we could determine whether conditions were favorable for the spread of plant pathogens, growers could make informed decisions on when to use chemicals.”

Whether a rain shower will spread these fungi is not a simple question of the amount of rain or duration of the shower, but rather a complex interaction of these factors with temperature, wind, humidity, and the size of the raindrops that fall, explained Madden.

“Large raindrops transfer more energy when they hit a surface, so they are much more likely than small raindrops to dislodge spores from an infected plant and spread them around,” said Madden. “Two rain showers may deposit the same amount of water, but if one contains larger raindrops than the other, it will be much more likely to promote the spread of water-borne crop diseases.”

If scientists had an easy way of detecting raindrop size, they could simply calculate the kinetic energy. The problem: standard rain gauges measure how much rain falls over time, but cannot record droplet size. Madden said the few sensors on the market today that do detect droplet size are both difficult to use and prohibitively expensive, costing as much as $30,000.

“We wanted an alternative way of determining kinetic energy of rainfall. We needed a sensor that worked under natural conditions where we have drops of many different sizes falling at the same time,” said Madden.

That’s why he and his students have been working with the Sensit Company of Portland, ND, to change the company’s soil erosion sensor into one that detects rainfall kinetic energy. The sensor features a two-inch disk of piezoelectric crystal that issues an electrical signal when raindrops land on it.

The researchers used a rainfall simulator to generate raindrops of different sizes, and recorded the sensor’s output for each size. Most raindrops measure between 1/100 in. and 1/5 in. wide, and the simulator can create any drop size in that range.

They then used that data to formulate equations that link the output of the sensor to the kinetic energy of the drops. The sensor data matched theoretical calculations for kinetic energy except in cases of very light rainfall.

Next, the researchers placed the sensor in a field at OARDC and took the same measurements for 85 natural rainfalls that occurred throughout 1996 and 1997.

The sensor revealed that a typical rain shower contains moments of high and low intensity rainfall. Moreover, it showed that both high and low intensity rainfalls varied widely in the kinetic energy of their raindrops. Madden said this supports the idea that the energy of rainfall should be measured by sensors, not estimated.

In the future, Madden and his students will use the sensor in their studies of the water-borne fruit rot disease anthracnose. Anthracnose commonly kills fruits such as strawberries -- the focus of Madden’s work -- as well as raspberries, blackberries, and tomatoes.

“From our laboratory work, we’ve learned some of the physical properties that determine how rain disperses spores. But even after years of study, we still don’t have a simple rule to follow -- we can’t say whether rainfall of a particular energy will definitely lead to an outbreak. The equations that we’ve developed here represent an important first step,” said Madden.

Researchers will likely be the only ones to use the sensor until they understand more about how rainfall relates to the spread of plant pathogens. After that, the sensor could work in weather stations alongside standard temperature and humidity sensors. Then the same agencies that issue crop advisories for insects and weeds could warn farmers about possible rain-borne pathogens.

The Sensit Company holds a patent on the sensor, and will continue to work with Madden and his students on future sensor modifications. Support for this work came from state and federal funds including a United States Department of Agriculture National Research Initiative Competitive Grant.


Story Source:

The above story is based on materials provided by Ohio State University. Note: Materials may be edited for content and length.


Cite This Page:

Ohio State University. "Study Of Raindrop Energy To Aid Fight Against Crop Diseases." ScienceDaily. ScienceDaily, 2 December 1998. <www.sciencedaily.com/releases/1998/12/981202075034.htm>.
Ohio State University. (1998, December 2). Study Of Raindrop Energy To Aid Fight Against Crop Diseases. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/1998/12/981202075034.htm
Ohio State University. "Study Of Raindrop Energy To Aid Fight Against Crop Diseases." ScienceDaily. www.sciencedaily.com/releases/1998/12/981202075034.htm (accessed September 20, 2014).

Share This



More Matter & Energy News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

What This MIT Sensor Could Mean For The Future Of Robotics

What This MIT Sensor Could Mean For The Future Of Robotics

Newsy (Sep. 20, 2014) MIT researchers developed a light-based sensor that gives robots 100 times the sensitivity of a human finger, allowing for "unprecedented dexterity." Video provided by Newsy
Powered by NewsLook.com
MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com
New Music With Recycled Instruments at Colombia Fest

New Music With Recycled Instruments at Colombia Fest

AFP (Sep. 19, 2014) Jars, bottles, caps and even a pizza box, recovered from the trash, were the elements used by four musical groups at the "RSFEST2014 Sonorities Recycling Festival", in Colombian city of Cali. Duration: 00:49 Video provided by AFP
Powered by NewsLook.com
Virtual Reality Headsets Unveiled at Tokyo Game Show

Virtual Reality Headsets Unveiled at Tokyo Game Show

AFP (Sep. 18, 2014) Several companies unveiled virtual reality headsets at the Tokyo Game Show, Asia's largest digital entertainment exhibition. Duration: 00:48 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins