Farm and Field

Corn-counting robot measures plant traits

Posted: Aug. 12, 2018 12:05 am

Crop breeders trying to boost yields while preparing crops to withstand severe weather and changing climates must locate genes for high-yielding hardy traits in crop plants' DNA.

A robot developed by the University of Illinois to find those "needles in the haystack" was recognized by the best systems paper award at a recent preeminent robotics conference.

"There's a real need to accelerate breeding to meet global food demand," principal investigator Girish Chowdhary, an assistant professor of field robotics in UI's Department of Agricultural and Biological Engineering and the Coordinated Science Lab, said. "In Africa, the population will more than double by 2050, but today the yields are only a quarter of their potential."

Crop breeders run massive experiments comparing thousands of different cultivars, or varieties, of crops over hundreds of acres and measure key traits, like plant emergence or height, by hand. The task is expensive, time-consuming, inaccurate and ultimately inadequate because a team can manually measure only a fraction of plants in a field.

"The lack of automation for measuring plant traits is a bottleneck to progress," first author Erkan Kayacan, now a postdoctoral researcher at the Massachusetts Institute of Technology, said.

Illinois' 13-inch wide, 24-pound TerraSentia robot is transportable, compact and autonomous. It captures each plant from top to bottom using a suite of sensors (camera), algorithms and deep learning.

"One challenge is that plants aren't equally spaced, so just assuming that a single plant is in the camera frame is not good enough," co-author Zhongzhong Zhang, a graduate student in the College of Agricultural, Consumer and Environmental Science, said. "We developed a method that uses the camera motion to adjust to varying inter-plant spacing, which has led to a fairly robust system for counting plants in different fields, with different and varying spacing and at different speeds."

The work was supported by the Advanced Research Project Agency-Energy as part of the TERRA-MEPP project at the Carl R. Woese Institute for Genomic Biology. The robot is available through the start-up company, EarthSense, Inc., which is equipping the robot with advanced autonomy and plant analytics capabilities.

Reports of southern rust

University of Missouri Extension confirmed the growing season's first case of southern rust corn disease in the U.S. in July.

The MU Plant Diagnostic Clinic confirmed that southern rust was present in a sample collected from west-central Missouri.

This common corn disease usually shows up in neighboring southern states before appearing in Missouri fields, but "this year is an exception," Extension plant pathologist Kaitlyn Bissonnette said.

Southern rust is a "tropical" disease that overwinters in warmer climates. Spores blow north on wind currents into corn-producing states each year. Unusually warm and humid weather across much of Missouri created the ideal environment for southern rust. As the fungus multiplies in the host tissue, raised structures called pustules form. Masses of spores erupt through the leaf tissue.

Management of southern rust depends on the crop stage and environmental conditions. For up to R3 (milk stage), applying a preventative fungicide may be beneficial.

"Take note of the current distribution of southern rust in the area, the growth stage of the crop and the environmental conditions. These are the most important factors to consider when making decisions to apply fungicides," Bissonnette said.