TIFTuf Drought Tolerant Bermudagrass Turf

Описание: Brian Schwartz, a turfgrass breeder at the University of Georgia shares the story of how TifTuf was developed.

One of the main goals I had when I started in Tifton in 2009, was to study the "why" of why TifTuf was remaining green in a drought. We did this by imposing drought under natural conditions as we have here in the Southeast but also under rainout structures where we can specifically exclude rain and study the responses of the grasses. From 2009 to 2013 I grew the grasses here in Tifton and at our other research station in Griffin, GA with Dr. Paul Raymer to study how this grass responded without supplemental water. For me, the first question was: Does TifTuf have deeper roots? So I spent two years taking one meter deep soil cores and measuring all winter long the roots from ten centimeter sections. After two years of long, hard research we found that TifTuf does not have more roots than Tifway for example. That was cool to hear from a scientific perspective but not helpful for my understanding of why TifTuf is so much more drought tolerant.

The next question was, How can we determine if it is using less water? One of the ways we can do this is to bury soil moisture probes about one meter deep into the ground. These probes allow you to track water use as a drought is coming through and the grasses are going dormant or becoming stressed. So we did another two years of research here in Tifton and Griffin where we studied the water content of the soil during a drought from Tifway, TifSport and TifTuf. We found very interesting results. It was our first indication ever of why TifTuf was more drought tolerant than Tifway or TifSport. As the drought continued the moisture in the soil under the TifTuf plots remained longer. You could see it dramatically on top as the Tifway and TifSport plots became dormant with drought the TifTuf plots did not. It was a direct correlation to the moisture level in the soil. It was really exciting because this is a great type of drought tolerance. If it goes brown that is ok but we would like a grass that stays green for longer and can save water.

Our results found that TifTuf can save 38% more water than a variety such as Tifway. If you expand that on a city, state or even on the South, that's a huge amount of water savings. Almost more interestingly, as we are saving water, the TifTuf plots and fields stay green longer. So it is that situation we hoped for that as a homeowner, gold course superintendent or sports turf manager goes out to their lawn or course and does not see stress, they aren't going to water, saving water and having a beautiful lawn at the same time.

It's important that we studied this in Georgia. But we had bigger plans for TifTuf, we wanted it to be used across the whole South. It's important to test a product before releasing a product that gets out to the public and then fails. We had great support from not only UGA and USDAARS but also received a federal grant to study the drought tolerance of bermuda, zoysia, St. Augustine and seashore paspalum grasses, under drought locations at seven farms at five universities across the US. Being that this grass was developed in 1992 it wasn't part of the grant per say but it was a drought standard. So it was planted at every trial and we watched the drought response in Oklahoma, Texas-College Station, Texas-Dallas, North Carolina-Raleigh, Florida-Gainesville, Florida-Jay, and Tifton, GA. We were able to collectively see the response of TifTuf across all these locations and it has been wonderful. During the first establishment phase it ranked righted along with Tifway and Celebration when well watered and growing in. But it showed better adaptation even at some of these locations and rated higher for turf quality. But the real difference came when we imposed drought across all these locations and TifTuf rose to the top. It was better than all the standard grasses: Tifway, Celebration, Latitude 36 on average across these locations. It was nice to see the results we saw here in Tifton correlated to what people were seeing across the rest of the country. The main point we can draw from this is that it isn't that TifTuf is perfect under long term drought, that would be misleading to say that is never looks not beautiful, but that it remains acceptable. That was our number one goal, as drought stress comes, TifTuf remained acceptable while others had gone completely dormant.

I've included some pictures here where you can see the end of our trials in which these had actually been abandoned. You can see Latitude 36 and Tifway almost completely dormant. Celebration looking a little bit better, which we would expect because that is an improved grass that came out more recently. But TifTuf looking as green as can be after almost a year of abandonment.