Progress 09/01/03 to 08/31/06
Outputs
These rotation trials were established in Alabama, Florida and Georgia to compare a 4 year rotation that included two consecutive years of bahia grass followed by peanuts and cotton with the conventional rotation of peanuts followed by two years of cotton. We showed the potential to increase economic return 3 fold by the fourth year of the rotation, but also that the producer makes less money the first year getting into the system due to absorbing the cost of the initial bahiagrass planting. We also showed that the economic gains were further enhanced through economic diversification (by adding hay and cattle to the system) which led to more stable profits for the producer. The second objective was to quantify the positive impacts that sod based rotations have on soil health, pest reduction, and sustainable farm production. It was shown that increased plant growth and yields were due in part to the enhanced soil conditions that bahiagrass created. Cotton plant biomass
and total N uptake at boll formation was greater for the bahiagrass rotated cotton compared to the peanut/cotton rotation. The cotton in the bahiagrass rotation also had larger root biomass and total root length compared to the peanut-cotton rotation. The soil in cotton plots in the bahiagrass rotation generally had less nitrates and ammonium at both levels above and below the compaction layer for most of season. There was also an increase in earthworms and water infiltration rates in the bahiagrass rotated plots as long as two years after bahiagrass was killed, Soil moisture was higher in the crops following bahiagrass especially during the high rainfall season which coincided with peak growth period for the crops. It was found that several peanut diseases were reduced when peanuts were grown after bahiagrass. The most surprising aspect was a consistent reduction in tomato spotted wilt, which is under further investigation to determine the underlying mechanisms of control. In this
system, double row peanuts helps reduce the negative impact of tomato spotted wilt virus, but can increase the severity of pod rot pathogens and sclerotinia blight. The final objective was to refine and promote production practices in a sod based rotation which result in significant yield increases associated with decreased inputs. This is still underway with increased peanut yields experienced each year. Thus far we have developed a very efficient and effective farming system that embraces the benefits of incorporating sod into a row crop rotation. It was determined that killing the bahiagrass in the fall before frost was the most efficient way to optimize peanut planting during the next season since bahiagrass roots were more decomposed and had less resistance to in row strip tillage, We have preliminary data to indicated that nitrogen rates could be reduced by at least 50% in the subsequent cotton crop due to increased root mass and efficiency. Weed mass has been noted to be less
in the crops grown after bahiagrass, and nematode pressure has been reduced in crops following bahiagrass.
Impacts
The impact of perennial grasses/livestock with row crops using conservation tillage has had predicted and unexpected aspects. It will continue to be investigated along with interactions on the environment and economics of the farm system by a team of scientists and graduate students. The rotation project has evolved to one of "the next step after conservation tillage" as this project has shown that perennial grass rotations, in combination with conservation tillage, can lead to an environmentally and economically sustainable farming system. This project will be highlighted at the Southern Conservation Tillage Conference in 2007 which will be hosted by the University of Florida and U Auburn University.
Publications
- Wright, D. L., Marois, J. J., Katsvairo, T. W., Wiatrak, P. J. & Rich, J. R. 2006. Rotation influence on cotton growth and development. 2006 proceedings:1821-1826
- Wiatrak, P. J., Wright, D. L. & Marois, J. J. 2006. Development and yields of cotton under two tillage systems and nitrogen application following white lupin grain crop. Journal of Cotton Science. 10:1-8
- Wiatrak, P., Wright, D. L. & Marois, J. J. 2006. The impact of residual nitrogen and tillage on wheat.. Soil and Tillage Research. 91:150-156 http://www.sciencedirect.com/science?_ob=ArticleListURL&_method=list& _ArticleListID=518449915&_sort.
- Marois, J. J., *Mailhot, D. J., Wright, D. L. & Wiatrak, P. J. 2006. Application of fungicides to reduce Fusarium hardlock of cotton in Florida. 2006 Proc.:1670-1675
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Progress 01/01/05 to 12/31/05
Outputs
Stagnant yields of peanut (Arachis hypogaea) and cotton (Gossypium hirsutum L.) coupled with increased production costs prompts the need to re-evaluate the current peanut/cotton cropping system in the Southern United States. We introduced bahiagrass (Paspalum notatum) to the current peanut/cotton cropping system to increase yields, reduce production costs and make the cropping systems more diverse and sustainable. Field studies were established in Quincy, FL., beginning in 2000. The objectives were to compare crop yields in the conventional peanut-cotton-cotton (P-C-C) vs. bahiagrass-bahiagrass-peanut-cotton (B-B-P-C) rotations under irrigated and nonirrigated conditions. Peanuts yields were consistently higher (up to 1100 kg/ha) in the bahiagrass rotation compared to the conventional rotation, under both irrigated and nonirrigated conditions. Improved soil conditions coupled with a reduction in diseases when peanuts follow a more effective host crop contributed to
the higher yields. Cotton lint yields did not differ for the two rotations, although cotton in the sod rotation resulted in almost 50% more biomass and root growth. In 2004, a year with reduced rainfall, cotton in the sod rotation had enhanced fibre quality including length, staple and strength, particularly under nonirrigated conditions. Cotton in the sod rotation extracted more P, K, Mg and Ca and resulted in less residual nutrients at the end of the season. Bahiagrass yields averaged over 8000 kg/ha. Percentage crude protein (CP) averaged 9.10, acid detergent fiber (ADF) 45.0 and neutral detergent fiber (NDF) 81.35 % for bahiagrass.
Impacts
This project continues to impact both producers and researchers. The concept of integration of bahiagrass and other perennial grasses into traditional cropping systems has resulted in gains in economic productivity, environmentally sensitive farming systems technology, and has served as an important source for the spin off of several other studies, including expansion the research through the T-STAR program to the Caribbean basin. It is expected that the program will continue to grow as more cooperators become interested in the possible areas of investigation. Other federal and state agencies, universities, producer groups, and growers are now joining the project or are establishing similar projects in their own areas.
Publications
- Katsvairo, T. W., D. L. Wright, J. J. Marois, D. L. Hartzog, and J. R. Rich. 2006. Performance of peanut, cotton and bahiagrass in sod-based cropping systems. Agronomy Journal Submitted
- Katsvairo, T. W., D. L. Wright, J. J. Marois, D. L. Hartzog, and J. R. Rich. 2006. Crop/Sod/Livestock diversification: A systems farming approach. Agronomy Journal Submitted
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Progress 01/01/04 to 12/31/04
Outputs
The rotation being studied is 2 years of bahia grass followed by peanuts and then cotton with winter cover crops and minimal tillage practices. Long term research plots were established at multiple locations, including neighboring states, including a 150 acre demonstration farm at the University of Florida and a 60 acre demonstration plot at the Auburn Wiregrass Research and Extension Center in Headland, Alabama. The web site for the project is http://nfrec.ifas.ufl.edu/sodrotation.htm. Ground water contamination is of major concern in the southeastern United States where reported ground water nitrate levels are as high as 22 ppm, well above the EPA limit set at 10 ppm. A significant amount of this N comes from row crops. We collected ground water samples from suction lysimeters installed at 6 and 40 inch depths in the cotton. N levels were higher for the shallower compared to the deeper depth (59 vs. 8 ppm) at the beginning of the season, however there were no
differences between the depths by the end of the season. The soil with cotton in the bahiagrass rotation generally had less nitrates and ammonium at both depths for most of season. N levels at the shallow depth decreased from 61 and 56 ppm for the peanut/cotton and bahiagrass rotation at the beginning of the season to 6 ppm for both rotations by the end of the season. Residual soil N at the end of the season was higher in the bahiagrass rotation. The bahiagrass rotated cotton developed a more extensive root system which utilized more N. Upon decaying, the larger rooting system in the bahiagrass rotation could have contributed to the higher soil N. A solution to this would be to keep the land under crop cover, so that the residual soil N can be utilized. The bahiagrass rotation had more surface residues compared to the conventional rotation. The higher organic matter supported more earthworms (24 vs. 3 at site 1 and 22 vs. 0 m -2 at site 2) while infiltration rates were also greater
for the cotton in the bahiagrass rotation. The higher earthworm densities could have partially contributed to the higher infiltration rates observed in the bahiagrass rotation. Soil moisture was mostly higher in the bahiagrass rotation compared to the conventional rotation (up to 30 vs. 38 volumetric moisture in July) throughout the growing seasons. Bahiagrass rotated cotton also had the larger total root area and root length. When bahiagrass roots die, they create channels and cotton roots can utilize the bahiagrass root channels to reach deeper soil profiles.
Impacts
This project will significantly enhance the economic value of row crop production in the southeast by increasing yields while decreasing production costs, it will reduce runoff and increase water use efficiency by allowing the row crops to establish deeper roots in the soil following bahiagrass, and it will reduce the need for many pesticides as the bahiagrass will reduce harmful plant parasitic nematodes and other insects and pathogens will be reduced due the the rotation.
Publications
- Katsvairo, T. W., D. L. Wright, J. J. Marois, D. L. Hartzog, P. J. Wiatrak. 2004. Soil water nitrogen in sod based peanut/cotton cropping systems. Abstract. Agronomy Society of America
- Katsvairo, T. W., D. L. Wright, J. J. Marois, and P. J. Wiatrak. 2004. Soil physical characteristics in sod based peanut/cotton cropping systems. Abstract. In Southern Branch Abstracts 2004 [CD ROM]. ASA, Madison, WI.
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Progress 09/01/03 to 03/31/04
Outputs
Two post doctoral people and two graduate students are currently working with the principal investigators in different phases of the sod based cropping system grant. Disease, insects, and nematode levels are being monitored. We have 8 locations in Alabama, Florida and Georgia to monitor different factors in the sod based cropping system including farm size plots. One location is under a 160 acre center pivot irrigation system set aside into quadrants with cow/calves pairs in rotation with cotton and peanut. Economic returns from these systems are being evaluated through the economic model developed for this system. Winter grazing is planted after the summer crops each year for the livestock. Soil health factors such as penetrometer measurements have been taken in the field using GPS technology along with bulk density, soil carbon, earthworm density, and water percolation rates. Intensive data is being taken from small plots in 2 locations with over 80 plots being
evaluated for soil, water, plant and pest responses to rotation with perennial grasses. Nitrate nitrogen is being measured weekly from lysimeters in conventional and sod based rotated cotton systems and data analyzed. Crop growth parameters and nitrate levels are being monitored in each of these systems to determine the value of conservation tillage and using perennial grasses for rotation. Yield and final production data will be determined from each location at the end of each year and reports written and presented at professional and grower meetings and written up for the scientific community. Each of these studies has a different role in verifying the economic model developed for perennial grasses and livestock with row crops. This project can have a major impact on farming systems in the Southeast and the U.S. with the research and extension components in place and the data being collected.
Impacts
This project will significantly enhance the economic value of row crop production in the southeast by increasing yields while decreasing production costs, it will reduce runoff and increase water use efficiency by allowing the row crops to establish deeper roots in the soil following bahiagrass, and it will reduce the need for many pesticides as the bahiagrass will reduce harmful plant parasitic nematodes and other insects and pathogens will be reduced due the the rotation.
Publications
- No publications reported this period
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