Progress 04/01/05 to 03/31/10
Outputs
OUTPUTS: A three year survey of grower fields in Louisiana determined that Diabrotica spp. are the predominant soil pests, followed by Phyllophaga ephilida, a white gub. We determined that pre-plant insecitcide applications contributed far less control of cucumber beetles than post-plant foliar applications. After quantifying the relationship between sweep counts of adult cucumber beetles and subsequent root damage at harvest, we established an economic threshold of 2 beetles per 100 sweeps. This information has been disseminated to grower groups through annual and regional meetings. Extension agents and crop consultants were informed through newletters and group meetings. Soil surveys of grower fields during this three year period indicated heavy reniform nematode populations in many fields. Reniform nematode infestations have a negative impact on sweetpotato yield. Our crop rotation research demonstrated that a corn, sorghum, or fallow rotation with sweetpotato could significantly reduce reniform nematode infestations. We now have a recommendation in our IPM program for a 2-year rotation, when possible, with these crops. Efficacy insecticide trials show Bifenthrin, a pyrethroid, effective against banded cucumber beetles and does not leach into the ground water. Growers now use this chemical as a preplant and foliar application to control cucumber beetles and white grubs, largely replacing the organophosphates, ethoprop, and chlorpyrifos. Sweetpotato weevil susceptibility of two cohorts has been evaluated in adult vial tests. Resistance ratios were determined from field collected samples of weevils from LA and wild host plants in Rio County, TX. Five active ingredients were evaluated. Weevils from both cohorts were most susceptible to methyl parathion and the cohorts were not significantly different. Bifenthrin and cyfluthrin were the next most toxic. The TX cohort had 1.5 and 2.3 (RR50) decreased sensitivity to cyfluthrin and bifenthrin, respectively, when compared to the LA cohort. To date, weevil resistance has not been documented in field populations. We demonstrated in field tests that novaluron (Rimon) was as effective as tebufenozide (Confirm) for control of Lepidopterous pests in sweetpotato. Novaluron received a full Sec 3 label in 2005. This research has identified new chemicals that have been registered for use in sweetpotato. Aggregation and feeding behavior of a recent pest of sweetpotato, the sugarcane beetle, was investigated in a Y-tube olfactometer. In behavioral trials, both male and female beetles responded significantly greater to female beetles conpared to male beetles. Both male and female beetle percent response was greater for beetle injured and mechanically injured roots than for intact sweetpotato roots. These results suggest that beetles are attracted to host plant volatiles released in response to wounding or insect feeding damage. Attraction of beetles to sweetpotato commercial fields may be due to a synergistic effect of host plant volatile release and the aggregation behavior of the beetles. PARTICIPANTS: Collaborators: Dr. Tara P. Smith, Ph.D., Chase Louisiana State AgCenter Sweet Potato Station, Dr. R. Story, Department of Entomology; Dr. C. Clark, Department of Plant Pathology and Dr. D. LaBonte, Department of Horticulture. Partner Organizations: Agricultural Experiment Station Personnel at North Carolina State University and Mississippi State University; Dr. Geroge Kennedy and Dr. Jack Reed, respectively. Dr. Craig Abel, USDA, ARS, Stoneville, Ms. Training: We trained county agents and consultants to recognize the major insect pests of sweet potato. Grants Received: We received a USDA, CSREES Grant to support parts of this research. TARGET AUDIENCES: Research results and IPM techniques were presented to the National Sweet Potato Council meetings held in California, North Carolina and Louisiana in 2006,2007 and 2008, respectively. During the 4 years of the project we reported annually to the Louisiana Sweet Potato Association meetings. Best Management Practices and IPM tactics were directed at growers, county agents and crop consultants. PROJECT MODIFICATIONS: Major changes occurred in pesticide application rates, timing and chemical class. New pyrethroids largely replaced the use of Mocap and Lorsban, EPA targeted organophosphate insecticides. Growers were trained to place pre-plant insecticides closer to planting of the crop. Pyrethroid insecticides are used at lower rates, ounces per acre. Crop rotation practices now include efforts to reduce nematode damage by recommended practices of two year rotations with corn, sorghum and fallow.
Impacts
Our data from field applications of either Capture, Lorsban, or Mocap applied as pre-plant or lay-by treatment along with timely foliar applications of labeled pyrethroids reduced damage from banded cucumber beetles and white grubs up to 85 percent. Using our recommended Best Management Practices and Integrated Pest Management techniques, growers could save as much as $8.6 million. In 2005, our research resulted in obtaining a Sec 18 for Capture, a pyrethroid. In 2006, with introductions of generic pyrethroids, the price dropped from $295 per gallon to $145 per gallon. Therefore Louisiana growers saved over $135,000 in foliar applied insecticide costs and $368,000 during the pre-plant growing season. We presented research results in 2007 and 2009 to multi-state producers at the National Sweet Potato Council meetings in California, North Carolina, and Louisiana, respectively. We developed one workshop for Louisiana growers and county agents and presented research results at grower meetings held in the 9-parish sweetpotato production area of Louisiana. We developed insecticide treatment schedules and control recommendations for growers. Each crop year for the past five years, we received grower, packer and canning company input during our research planning meetings held yearly by the LSU AgCenter.
Publications
- Journal Articles: Hammond, Abner M.,R. Story, T.P. Smith and J. Murray,(2009). Season-Long Management of Banded Cucumber Beetle in Louisiana Sweet Potatoes. Louisiana Agriculture, Vol:52, Spring, 2009.
- Smith,T.P.,A.M.Hammond,R.N.Story and E.Burris. (2010).Comparison of Banded Cucumber Beetle (Coleoptera:Chrysomelidae) and Cumulative Soil Insect Damage in Three Sweetpotato Varieties Evaluated Under Selected Insecticide Regimes in Louisiana. Mid-South Entomologist (In Press).
- Book Chapter: Gao Y.,L. Luo and A. Hammond. 2009. Antennal Sensillar Morphology, Structure and Function in Parasitic Wasps, Chapter 7,In A.I.Ferrero (ed), "Antennas: Parameters, Models and Applications" Nova Science Publishers, Inc. Hauppauge, N.Y., p.191-211.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Sweet potato growers have adopted our program to shorten the interval of pre-plant insecticide applications to just precede initial plantings of the crop. This practice has extended the life of effective soil applied insecticides and has resulted in improved control of white grubs and banded cucumber beetle larvae. We developed and educated growers to use pyrethroid insecticides for control of sweet potato insect pests. The use of bifinthrin (Capture) and generic alternative chemicals reduced the cost of insecticide applications sighificantly. We solicited and incorporated grower concerns into our sweet potato research program. We conducted 3 field verification programs on farm to educate growers on the latest best management practices for sweet potato production. PARTICIPANTS: Collaborators: Dr. Tara P. Smith, Louisiana Agricultural Experiment Station, Chase Louisiana. Dr. Christopher A. Clark, Department of Plant Pathology and Crop Pyhsiology, LSU AGCenter. Dr. Don LaBonte, Department of Horticlture, LSU AGCenter. Dr. R. Story, Department of Entomology, LSU AGCenter. Professional training occured at the Entomological Society of America annual meeting. Reno, Nevada. Nov. 15-Nov. 19 2008. Professional sessions were attended on pesticide regulation, development of insect pheromones for pest control and integration of sustainable insect management programs into sweet potato production. TARGET AUDIENCES: Louisiana Sweetpotato Association meeting, January 11 and 12, 2008; Mansura, Louisiana. Attended by 62 growers, packers and shippers representing the industry. Presented oral presentations designed to change grower practices regarding insecticide application timeing and methods. LSU AgCenter, LA. Experiment Station, Sweetpotato field day, Chase,Louisiana. August 14, 2008. Presented in-field talks to about 41 growers interested in insecticide efficacy, new insecticides for the sweetpotato industry ,and we demonstrated effective ways of applying layby insecticide treatments. Louisiana State-wide Sweetpotato Advisory meeting held on Dec.4, 2008 to listen to grower concerns concerning issues that effect grower profits and sustainability. There were 21 growers in attendance. Researchers shared future plans and growers prioritized their research needs. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
During the past 3 years we have developed and registered a pyrethroid insecticide, bifenthrin, as both a pre-plant and a layby chemical for soil application. This new chemical for the sweet potato industry has greatly reduced the need for either chlorpyrifos or ethoprop, both organophosphates targeted by EPA for restricted use in field crops. The price differences between uses of the organophosphates and the pyrethroids have resulted in a savings to growers of $45-$85 per acre or from an average of $875,000 to $1,275,000 per year. The subsequent labeling of generic pyrethroids has resulted in a savings of over $135,000 to Louisiana growers using these chemicals to control sweetpotato weevil in the quarantine zone of Louisiana. In addition, since most of Louisiana's sweet potato acreage is treated with pre-plant insecticides, using generic pyrethroids has resulted on average a savings of $368,000 to growers during planting season, May throught July 15. One Louisiana sweet potato grower said, "some years, as much as 20% of our crop is lost to a combination fo soil and foliar feeding insects, and we are excited to have a less expensive, effective pyrethroid insecticide to reduce our risk and cut pest control costs."
Publications
- Hammond, A. M., R. N. Story and M. J Murray. 2008. Evaluation of preplant and lay-by insecticides for control of banded cucumber beetles and white grubs in sweet potatoes, 2007. Arthropod Management Tests 33:E18.
- Story, R. N., A. M. Hammond and M. J. Murray. 2008. Evaluation of insecticides for control of cucumber beetles and white grubs in sweet potatoes, 2007. Arthropod Management Tests 33:E53.
- Story, R. N., A. M. Hammond , M. J. Murray and T. P. Smith. 2008. Evaluation of preplant and foliar insecticides in five grower fields for control of banded cucumber beetles and white grubs in sweet potatoes, 2007. Arthropod Management Tests 33:E52.
- Story, R.N., M.J. Murray, A.M. Hammond, D.R. LaBonte. 2008. Evaluation of sweet potato germplasm for resistance to sweetpotato weevil, 2007. Arthropod Management Tests 33:M3
- Smith, Tara. P., A. M. Hammond. 2008. Managing Sweetpotato Weevils in South Louisiana. Louisiana Agriculture. 51 (1):20-21.
- Hammond, A. M., R. N. Story, T.P. Smith, and M. J Murray. 2009. Evaluation of preplant insecticides for control of white grubs in sweet potatoes, 2008. Arthropod Management Tests 34:
- Story, R. N., A. M. Hammond , M. J. Murray and T. P. Smith. 2009. Evaluation of lay-by insecticides for control of white grubs in sweet potatoes, 2008. Arthropod Management Tests 34:
- Story, R. N., A. M. Hammond , M. J. Murray and T. P. Smith. 2009. Evaluation of preplant and lay-by insecticides for control of banded cucumber beetles and white grubs in sweet potatoes, 2008. Arthropod Management Tests 34:
- Story, R. N., A. M. Hammond , M. J. Murray and T. P. Smith. 2009. Evaluation of lay-by insecticides for control of banded cucumber beetles in sweet potatoes, 2008. Arthropod Management Tests 34:
- Smith, Tara P., C. Overstreet, C. Clark, D. Ferrin, and E. Burris. 2008. Nematode Management. Louisiana Sweet Potato Production. Louisiana Cooperative Extension Service Pub. 3075.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: We were able to present 2006 and 2007 research results to sweet potato producers at the Natonal Sweet Potato Council meetings in San Francisco and North Carolina. We developed one workshop for growers and county agents and presented research results at grower meetings held in the 9 parish sweet potato production areas. We received grower, packer and shipping input for our research considerations during the 2008 crop year.
PARTICIPANTS: In Louisiana collaborative research was conducted with Drs. R. N. Story, T. P. Smith and Christopher Clark. RAMP Grant research was conducted in collaboration with Mark Abney, NC State University, and Jack Reed, Mississippi State University. Data and research results were shared at a joint meeting of the Sweet Potato Collaborators Group in 2006, 2007. Personal professional development opportunities occured at the annual meeting of the National Entomological Society and the Southeastern Branch Meeting. I also attended the annual meeting of the National Sweet Potato Council.
TARGET AUDIENCES: We conducted 2 training sessions for grower/shippers and county agents on the value of Louisiana's IPM program for insect control in Sweet Potatoes. We published two grower advisory papers through the Louisiana Cooperative Extension Service.
PROJECT MODIFICATIONS: We have completed a 4 year sweet potato crop rotation study comparing insect damage following corn, cotton, sweet potato, fallow and soybean. Data have not been completely analyzed but damage estimates, yield and nematode information will be forthcoming. We will be able to recommend the best crop rotation plan for Louisiana sweet potato growers in 2008.
Impacts
Louisiana sweet potatoes were harvested in 2007 on 13,500 acres, down 3,500 acres from a disastrous 2006 harvest season. US number 1 grade sweet potatoes are valued at $13/$14 per 40 lb. box at the farm gate for a net value of $4,256.00/acre in 2007. Banded cucumber beetles and white grubs damage on average about 25% of marketable storage roots in any given season. Risk Avoidance and Mitigation (RAMP) field trials were conducted in the 3 Louisiana areas where sweet potatoes are produced. Research objectives were to: 1) conduct sweep net sampling for banded cucumber beetles and correlate beetle counts with root damage; 2) evaluate early, mid-season and late season planting dates because beetle abundance may be influenced by crop development during the growing season and 3) determine the efficacy of several insecticides used as a pre-plant or lay-by treatment in combination with foliar applications to reduce beetle and white grub damage seen at harvest. Our data from
field applications of either Capture, Lorsban or Mocap applied as a pre-plant or lay-by treatment along with timely foliar applications of labeled insecticides reduced damage from these two soil pests by as much as 85%. There was a positive correlation between the seasonal mean number of beetles sampled and the percentage of roots damaged. Our regression analysis supports an economic injury level of 2 beetles per 100 sweeps that corresponds to 5 percent root damage. This is the first data based assessment of a threshold for cucumber beetles in sweet potato. An effective IPM program based on these data and timely, efficient use of a pre-plant and foliar insecticide may maintain damage levels below the economic injury level. Using recommended Best Management Practices and Integrated Pest Management techniques, growers could save as much as $8.6 million.
Publications
- Hammond, A. M., R. N. Story and M. J Murray. 2007. Evaluation of preplant and lay-by insecticides for control of banded cucumber beetles and white grubs in sweet potatoes. Arthropod Management Tests.2008.
- Story, R. N., A. M. Hammond and M. J. Murray. 2007. Evaluation of insecticides for control of cucumber beetles and white grubs in sweet potato. Arthropod Management Tests.2008.
- Story, R. N., A. M. Hammond , M. J. Murray and T. P. Smith. 2007. Evaluation of preplant and foliar insecticides in five grower fields for control of banded cucumber beetles and white grubs in sweet potatoes. Arthropod Management Tests.2008
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Progress 01/01/06 to 12/31/06
Outputs
Insects that damage sweet potatoes are significant and numerous. Soil insects, such as rootworms, white grubs, and sweetpotato weevils are the top 3 pests in Louisiana. Research was conducted in 22 sweet potato fields and involved 12 commercial growers in 2006. Each field was sampled throughout the entire growing season and insect damage was compared between three treatments; untreated, preplant only and preplant plus foliar applications. Rootworm damage in untreated, preplant only and foliar treated plots was 21, 16 and 6 percent, respectively. Significant damage reduction occurred when growers used an economic threshold of 2 beetles per 100 sweeps in an IPM program. Growers use a preplant application of Capture, Lorsban or Mocap to control white grubs. In our test plots in 2006, white grub damage averaged 11, 12 and 14.5 percent in untreated, preplant and preplant plus foliar sprays, respectively. Results suggest that preplant applications of these insecticides do
not reduce overall damage from white grubs when comparing untreated to preplant insecticide treatments. However, in a Mocap phytotoxicity study at Burden Research Farm percent white grub damage was reduced 79 percent with 3 lbs Mocap immediately before transplanting and 72 percent with 0.5 percent Capture applied in furrow. Stand counts were made in each treatment 2 weeks after planting and yields were measured. Mocap had no adverse effect on plant stand or yield. Future research should focus on IPM recommendations to growers regarding these preplant insecticides for control of white grubs. Are they necessary or how should they be applied to provide some degree of control? The effect of crop rotation sequences on reniform nematode populations, soil insect damage and sweet potato yield is currently being evaluated at the LSU AgCenter Dean Lee Research Station. Six crops are in a 4 year rotation scheme. The 2007 crop season will mark the final year and sweet potato will be planted in
all plots. Nematode samples were collected from each plot in 2005 and 2006. In 2006, sweet potato plots were harvested and separated into U.S. No. 1, canner and jumbo grades for yield comparisons. Insect damage ratings were taken in each sweet potato plot. In 2007, nematode counts, insect damage and yield will be compared to determine the best crop for rotation with sweet potato. Results thus far support our current IPM practice of rotating sweet potato with grass crops such as corn and grain sorghum to reduce nematode populations. During the winter of 2005, 526 surveys were sent to commercial sweet potato growers in five states. On average, growers treated close to 90 percent of their acreage with insecticides. Louisiana growers average 9 applications per season. This number reflects state regulations mandating insecticide applications to control sweetpotato weevil. In a toxicological study comparing susceptibility of a field collected, Louisiana cohort vs. a Texas cohort collected
from wild host plants there was a 5-fold increase in resistance in the Louisiana cohort. Therefore, a resistance monitoring program will be initiated in Louisiana to monitor sweetpotato weeevil populations.
Impacts
Louisiana growers planted about 16,075 acres of sweet potatoes in 2006. Heavy rains in mid-October ruined 25 percent of the harvestable crop. In addition to weather, soil insect pests such as rootworms, white grubs and sweetpotato weevils cause significant economic losses, even in low numbers. In a grower survey of over 60 separate fields in a 3-year period (2004-2006), 15.5 percent of the roots were damaged by rootworms in untreated test plots. White grub damage averaged 4.8 percent in the same plots. Before 2003, soil insect control was based exclusively on FQPA-targeted insecticides, such as chlorpyrifos, ethoprop, phosmet, methyl parathion and endosulfan. Our research with bifenthrin, a pyrethroid, that binds to the soil and does not leach into ground water, has allowed us to replace some of the insecticide applications with newer chemistry. In 2005, Capture, a pyrethroid, labeled under a Sec 18 cost $295 per gallon. In 2006, with introductions of generic
pyrethroids the price dropped to $145 per gallon. Thus, growers saved over $135,000 in foliar applied insecticide costs and $368,000 during the planting season.
Publications
- Diagne, A., R.N. Story, and A.M. Hammond. 2006. Partial Life Cycle of Phyllophaga ephilida Say (Coleoptera: Scarabaeidae) in South Louisiana. J. Entomol. Sci. 41(4):409-411.
- Diagne, A., R.N.Story, and A.M. Hammond. 2006. Adult Phyllophaga ephilida Say Host Plant Feeding Preference. Florida Entomologist. 83(3):391-395.
- Robbins, P.S., Hammond, A.M., et al. 2006. Trapping Phyllophaga spp. (Coleoptera: Scarabaeidae: Melolonthinae) in the United States and Canada using sex attractants. J. of Insect Sci. Vol. 6(39): Available online: insectscience.org/6.39.
- Smith, T.P. and A.M. Hammond. 2006. Comparative Susceptibility of Sweet Potato Weevil (Coleoptera: Brentidae) to Selected Insecticides. J. Econ. Entomol. 99(6):2024-2029.
- Gao, Y., Li-Zhihuo, and Abner Hammond. 2006. Micron Antennal Morphology, structure and sensilla distribution in Microplitis pallidipes (Hymenoptera: Braeonidae). Micron (2006), doi:10.1016/j.micron. 2006.09.004
- Smith, T.P., J.H. Temple, A.M. Hammond, and P.L. Bommireddy. 2006. Residual Activity of Foliar-Applied Insecticides to Control Banded Cucumber Beetle, 2006. Arthropod Management Tests. 31, Report No. E66.
- Smith, T.P., B.R. Leonard, A.M. Hammond, and R. Gable. 2006. Managing Sugarcane Beetles in Field Corn with Seed Treatments. Louisiana Agriculture. 49(4):27-28.
- Smith, T.P. 2006. Biology and Chemical Ecology of the Sugarcane Beetle and Integrated Pest Management of Sweet Potato Soil Insects in Louisiana. Ph.D. Dissertation. Louisiana State University, 110 pp.
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Progress 01/01/05 to 12/31/05
Outputs
Research was conducted in 21 sweet potato fields and involved 12 growers in 2005. Each field was sampled throughout the season and insect damage was compared between an untreated test plot and grower practices. Significant damage reduction occurred when growers used recommended IPM practices to control adult rootworms and white grub larvae. MocapR, LorsbanR, and CaptureR applied as preplant only, without foliar seasonal treatments, did not reduce rootworm damage. Foliar insecticide applications are effective against rootworm adults. Detailed significance of this research is available in RAMP CSREES reports. Our IPM insecticide program consists of pre-plant applications of Mocap, Lorsban or Capture. Possible phytotoxicity following application of Mocap resulted in evaluation of this product in replicated small plot tests. Treatments consisted of Mocap vs.no Mocap following 1,3,7, and 14 days after planting. Stand counts were made in each treatment 2-weeks after
planting and yields measured. Mocap had no effect on yield (P=0.8762, ANOVA). Adult vial tests were conducted to determine susceptibility of two cohorts of sweetpotato weevils to five chemicals of formulated insecticides. Resistance ratios were determined using field collected samples of weevils from LA and from wild host plants in Rio County, TX. The number and range of concentrations varied for each cohort and chemical tested. They were: (bifenthrin,7, 0.175-1.25); (methyl parathion,6, 0.0125-0.125); phosmet,6, 0.5-100); (cyfluthrin,6, 0.5-5); (carbaryl,7, 0.25-100); Mortality was determined 24h after exposure in all tests. All data were subjected to probit analysis (PROC PROBIT, SAS Institute, 1999. Resistance ratios and 95% confidence intervals were calculated. Weevils from both cohorts were most susceptible to methyl parathion and the cohorts were not significantly different. Bifenthrin and cyfluthrin were the next most toxic. The TX cohort had 1.5 and 2.3 (RR50)decreased
sensitivity to cyfluthrin and bifenthrin, respectively, when compared to the LA cohort. To date,weevil resistance has not been documented in field populations. Host plant preferences were determined for the sugarcane beetle using choice tests in the greenhouse. Seven plant species were chosen. Logistic regression (PROC LOGISTIC, SAS Institute 1999)was used to examine the relationship between beetle behavioral responses and plant species. Sweet potato was significantly more preferred that all other hosts; 50% more preferred than corn and sugarcane. Strawberry and rice were the least preferred, followed by Bermuda grass. Beetles have gone unrecognized as a pest of sweet potato. Aggregation and feeding behavior of the sugarcane beetle was investigated in a Y-tube olfactometer. In olfactometer trials, both male and female beetles responded significantly greater to female beetles compared to male beetles. Both male and female beetle percent response was greater for beetle injured and
mechanically injured roots than for intact sweet potato roots. Attraction of beetles to sweet potato commercial fields involves host plant volatile release and the aggregation behavior of the beetles.
Impacts
Louisiana sweet potatoes were harvested on about 17,000 acres with a net value of ca.$1700/acre. Root feeding insects damage on average about 27% of the roots in a field in any given season. Pre-plant soil applications of Lorsban and Mocap provide a reduction in damage to roots, thus saving growers as much as $8.5 million. Sweetpotato weevil and banded cucumber beetles can be a major cause of damage in the quarantine areas of Louisiana. Capture, a Section 18 material, and Penncap M applied at 7 to 10 day intervals beginning 45 days post-transplant saved growers $ 18 million, according to USDA and State of Louisiana estimates. Laboratory bioassays with technical grade insecticides of labeled products indicate a moderate change in insecticide susceptibility of field collected Louisiana weevils compared to an untreated population from Texas. Resistance ratios indicate a >2 fold decrease in susceptibiliy for 4 of 5 insecticides evaluated against the two populations. This
research suggests that insecticide resistance monitoring is a necessary activity conducted by entomologists in the LSU AgCenter.
Publications
- Smith, T. P., B. R. Leonard, and R. H. Gable. 2005. Evaluation of neonicitinoid insecticides as seed treatments on corn for control of sugarcane beetle adults, 2004. Arthropod Management Tests Vol. 30, (In http://www.entsoc.org/Protected/AMT/AMT30/Text/amt30.asp.?Report=F??) .
- Story,R.N.,A.M.Hammond,M.J.Murray and D.R.LaBonte.2005. Evaluation of sweetpotato germplasm for resistance to sweetpotato weevil, 2004. Arthropod Management Tests Vol. 30, (In http://entsoc.org/Protected/AMT/AMT30/Text/amt30.asp.?Report=M5.
- Sexon,D.,J.Wyman,C.Granadino,S.R.Mahr,C.Eastman,W.Chaney,R.Story and A.M.Hammond. 2005. Root crops.Chapter 6,109-124. In Vegetable Insect Management. R.Foster and B.R.Flood,eds. Meister Media Worldwide, Willoughby,Ohio.264pp.
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