Location: Sugarcane Research
2016 Annual Report
Objectives
The main objectives proposed in this Project Plan are to develop and improve sustainable management strategies for weeds and insects. Effective integrated pest management (IPM) programs are vital to a sustainable cropping system. Over the next 5 years, the project will focus on the following objectives:
Objective 1: Evaluate newer herbicide chemistries (i.e., 4-hydroxyphenylpyruvate (HPPD) inhibitors, cell wall biosynthesis inhibitors, etc.) for efficacy of weed control in sugarcane and crop safety, as well as older, currently registered herbicides to improve weed management (tank-mix combinations, timing of application, use of spray adjuvants, etc.).
Objective 2: Evaluate cultural control methods for reducing weed interference in sugarcane including, but not limited to: varietal differences in competitiveness of sugarcane, inter-row tillage timing, type, frequency, and rotational crops (including green manure cover crops) that could be used during fallow season compared with chemical fallow, and site-specific management.
Objective 3: Enhance the role of plant resistance in managing damaging infestations of stem borers (i.e., sugarcane borer and Mexican rice borer) in sugarcane.
Sub-objective 3.A: Characterize fiber among commercial sugarcane cultivars resistant to the sugarcane borer and Mexican rice borer.
Sub-objective 3.B: Identify borer resistant progeny in high sucrose bi-parental crosses.
Objective 4: Identify control tactics for managing damaging infestations of a hemipteran complex (e.g., sugarcane aphid, yellow sugarcane aphid, West Indian canefly, and sugarcane delphacid) to include the role of soil health on these infestations and new insecticides for controlling the complex.
Approach
The approach to meeting the objectives of this project plan will be primarily in the form of replicated field experiments. Some of these field experiments will also be supported by laboratory analyses. New herbicide chemistries, when they become available, will provide the potential for greater efficacy in weed control; however, determining appropriate application rates, application timing, and application methodology will require replicated field experimentation that are repeated in multiple years. Results from these experiments will be used for obtaining labeling by EPA and ultimately in formulating extension recommendations to sugarcane growers. Cultural controls provide opportunities for reducing weed pressure by planting sugarcane varieties with greater competitiveness resulting in more efficient tillage practices (i.e. fewer cultivations). Planting rotational crops (e.g. soybean and sweet sorghum) will provide an additional income stream to growers while also aiding in suppressing weed infestations. To develop these improved cultural practices will also require a series of field experiments. The results from these studies will also be used to develop extension recommendations for sugarcane growers. Enhancing the role of plant resistance in controlling the sugarcane borer and Mexican rice borer will require a more in-depth knowledge of fiber composition in commercial sugarcane varieties. A replicated field experiment consisting of sugarcane varieties with known reaction to sugarcane borer and Mexican rice borer will provide plant tissue for detailed fiber analyses. Ultimately a fiber profile will be qualified and quantified that will allow selection for stem borer resistance in the absence of the insect pest. Finally, field experiments will be conducted to identify control tactics for managing damaging infestations of a four-species hemipteran complex infesting sugarcane. These experiments will seek to better refine damage thresholds and ultimately establish action thresholds for initiating insecticide applications. The most effective insecticide formulations will need be to be identified as well as determining their most economical application rates. Ultimately, the findings from this Project Plan will be used to develop improved and sustainable management strategies for weeds and insects pest of sugarcane primarily in Louisiana, but the findings are generally applicable for sugarcane grown in Florida and Texas.
Progress Report
Two studies were planted in the fall of 2015 with HoCP 96-540 and L 99-299 to determine the effects of several new herbicides on crop injury, weed control, and cane and sugar yields. Herbicide treatments were applied in the spring of 2016 and crop injury and weed control ratings were taken later in the spring. Stalk counts and heights will be measured in August and cane and sugar yields will be determined in November or December 2016.
In April of 2016, soybeans and sweet sorghum were planted in an experiment established at the Sugarcane Research Unit’s (SRU) research farm near Houma, Louisiana, to study the effect of potential allelochemicals from these crops on subsequent cane and sugar yields. Soybeans and sorghum will be harvested in August and September, fields will be cultivated, rows re-established, and sugarcane variety L 99-299 will be planted. Soil samples will be taken prior to planting cane to determine the presence of potential allelochemicals. Sugarcane yields will be measured by harvesting the plots in the fall of 2017.
An experiment was initiated in fiscal year 2016 at the SRU’s research farm to evaluate the effect of sugarcane stalk fiber level on sugarcane borer infestations. Four varieties, with varying levels of stalk fiber, were planted in a replicated test. Stalk total fiber levels and fiber components will be measured starting in June of 2017, and will continue on a monthly basis until plots are harvested in November 2017.
In fiscal year 2016, an experiment was established in a commercial plant-cane field of sugarcane variety HoCP 96-540 to measure the levels of sugarcane hemipteran pests. The field was grid-sampled with 52 sampling points established. Soil samples were collected at each sample point and stalk heights and pest numbers were determined on a weekly basis. Cane and sugar yields will be determined by harvesting selected rows of the field in November 2016.
Accomplishments
None.
Review Publications
Webber III, C.L., White Jr, P.M., Dalley, C.D., Petrie, E.C., Viator, R.P., Shrefler, J.W. 2016. Kenaf (Hibiscus cannabinus) and cowpea (Vigna unguiculata) as sugarcane cover crops. Journal of Agricultural Science. 8(8):13-20.
Eggleston, G., Andrzejewski, B., Cole, M., Dalley, C., Sklanka, S., St Cyr, E., Chung, Y., Powell, R. 2015. Novel storage technologies for raw and clarified syrup biomass feedstocks from sweet sorghum (Sorghum bicolor L. Moench). Biomass and Bioenergy. 81:424-436.
