By Madeline Fisher
Apr. 17. 2012 -- North American growers have been practicing precision agriculture for decades, and one look at the average farm shows why. Fields are dozens to hundreds of acres in size, making it wise to tailor crop inputs to the natural variability in soil properties and other growth conditions that exists at large scales.
Precision Agriculture Project scientists with participating rice paddy farmers.
But how about in India, where the typical farm is just 5 acres or less? Does enough variability exist in small fields to warrant precision farming there, as well? That’s the question now being addressed in the southern Indian state of Karnataka, where a state government grant ($220,000 in U.S. dollars) is supporting a new Precision Agriculture Project at Karnataka’s three agricultural universities. The project’s lead institution is the University of Agriculture Sciences (UAS), Raichur, in northeastern Karnataka, and its coordinator is M.B. Patil, a UAS plant pathologist.
In 2010, Patil traveled to Colorado State University in Fort Collins, CO, to learn about precision farming in the laboratory of soil science professor and precision agriculture expert, Raj Khosla. Khosla, in turn, has a grant from the Indian government’s Department of Science and Technology to help UAS build its capacity to teach, study, and disseminate the practice. He has also conducted more than a dozen precision agriculture workshops across India during the last five years.
Under Khosla’s guidance, Patil and a team of scientists and local farmers are now conducting grid-sampling of conditions such as soil fertility, plant nutrient status, and crop health on area farms for the first time. Once they’ve mapped these parameters within fields, they’ll attempt to correlate the variability they see in these measurements with variability in crop yields.
Already they’re documenting significant differences in soil properties and crop characteristics across fields of just 2.5 to 5 acres in size, and in some cases the scale of variability is similar to what researchers observe in large fields of Colorado, Khosla says. Although much more work remains, the findings make him and Patil hopeful that variable rate fertilizer applications and other techniques can one day increase yields of northeastern Karnataka’s three major crops: rice, pigeon pea, and cotton.
Making progress on a pressing need
Precision agricultural techniques and concepts are urgently needed in India and other developing countries, Khosla says. Many nations struggle with low, stagnating, and declining crop yields—despite being heavy consumers of water, nitrogen, and other inputs. China and India are currently the world’s largest users of fertilizers, and developing nations as a whole consume 60 to 70% of global fertilizer supplies. Meanwhile, global nitrogen use efficiency hovers around 40%, suggesting that precision farming has a lot of potential to optimize inputs and boost yields in India and elsewhere.
Precision Agriculture Project Coordinator, M.B. Patil, delivers a lecture to pigeon pea farmers on precision farming techniques.
Yet, until recently, most farmers in developing countries weren’t able to measure properties like plant nitrogen status, soil moisture, or electrical conductivity at all—much less map these parameters in fine detail within fields. Instead, they’ve made choices about where and when to spread fertilizers or seed based on differences in soils and plant growth they can see by eye, as well as their historical knowledge of the land.
Now that precision farming tools and data are becoming available, however, the project’s participating farmers couldn’t be more enthusiastic about them, Patil says. After one local farmer used GPS to map the location of his farm, he asked his son to put the farm’s coordinates into Google Earth on a laptop. “They were so happy,” Patil says. “It was the first time they understood the location of their farm on the Google Earth image.”
Another farmer is so excited about the variability being revealed by grid-sampling that he’s making a book of every 50 by 50 meter (150 by 150 foot) grid on his farm, including the nearly 50 observations that have been taken in each during the growing season.
During his time in Colorado, Patil learned that involving farmers from the start is critical to taking precision agriculture from research plots to actual farms, because these early experiences build their confidence in the technology and begin showing them that farming can be done in a precise way. The project is already working with nearly 50 local farmers, and has enrolled roughly 100 acres each of pigeon pea, cotton, and rice in its grid-based studies of soil properties.
Project scientists are also in the process of acquiring satellite imagery of all the project’s cropping areas. Once the images are in hand, the researchers will compare them against the actual crop growth on the ground to see “how the image tells the story” of what’s happening in the field, Patil says.
The next stage
Mapping variability is only the beginning, of course. The next step will be to apply fertilizers and other inputs according to location-specific conditions—a challenging proposition, Patil admits. Right now, the team adds fertilizers to the grids in study fields by hand, and many local farmers still spread fertilizers and harvest crops by hand, as well.
The opening of the UAS, Raichur, Precision Agriculture Research Laboratory on Dec. 22, 2012. Pictured from left to right are L.B. Hugar, Dean of the College of Agriculture; Raj Khosla, president, International Society of Precision Agriculture, and professor, Colorado State University; B.V. Patil, Vice Chancellor of UAS, Raichur; and M.B.Patil, UAS Precision Agriculture Project Coordinator.
But mechanized paddy transplanters, small combine harvesters, and other machines are becoming much more common in Karnataka, Patil says. The technology is still relatively expensive for Indian farmers, but the government offers subsidized loans to purchase farm machinery, and farmers also share the equipment willingly, just as they’ve shared labor in the past. When Patil explained to one farmer that a GPS unit cost 5 lakh rupees, or $10,000 U.S. dollars, for example, Patil thought the farmer would object to the price. “But immediately he said, ‘No, no, we’ll get it. We’ll share it among 10 farmers,’” Patil recalls. “’We’ll get it if it is useful to us.”
With Karnataka carved into so many tiny farms, cooperation will in fact be the key to success in precision farming, he adds. “A very wild ambition of this precision agriculture project is that in our fragmented farming community the farmers will get together.” Already a precision farming cooperative is being planned for one regional crop, and other farmers outside the UAS project are expressing interest in precision farming practices, too.
In the meantime, the UAS College of Agriculture launched a Precision Agriculture Research Laboratory last December, with Khosla in attendance. Equipped with the latest tools—including Trimble GPS units, Arc GIS, ERDAS imaging software, Skype radiometers, and handheld sensors like the Greenseeker—the lab will offer a course in precision farming and host a series of trainings this year for faculty, students and extension agencies, in addition to doing research.
While this rapid progress is encouraging, however, Patil cautions that the project doesn’t want to expand too quickly. Rather, it wants to take the time to do things right. “Already other countries have spent 20 to 30 years doing precision agriculture, but we’re in the infancy,” Patil says. “So we want to understand, convince ourselves first, of what exactly is happening in the field.”
Photos courtesy of M.B. Patil.