Category Archives: Peanut

EPA decision on chlorpyrifos

The head of the EPA, Scott Pruitt, signed an order last night denying the petition to ban chlorpyrifos (Lorsban). This decision will allow peanut growers in our area the continued use of this insecticide for the foreseeable future, perhaps until 2022 when the EPA is required to reevaluate safety of this product. The environmental group that filed the 2007 petition to ban chlorpyrifos has announced its plans to appeal the decision.  More information can be found here – https://www.epa.gov/newsreleases/epa-administrator-pruitt-denies-petition-ban-widely-used-pesticide-0

Scout now for marestail/horseweed

Recent mild temperatures and the mild winter are setting the stage for rapid development of marestail/horseweed (Conyza canadensis) this spring.  Marestail was particularly troublesome last year in soybeans.  Marestail can germinate in both the fall and the spring. It is more likely to overwinter in the rosette stage during mild winters.  If you wait until your typical burndown the marestail may start bolting and therefore be more difficult to control. Adding to this difficulty, many marestail populations are resistant to Roundup (and other glyphosate containing products). You should scout your fields targeted for soybeans now to identify overwintering marestail.  Marestail control can be achieved with 2,4-D  or dicamba now and still offer plenty of time to avoid plant back restrictions (up to 15 days for 2,4-D or up to 28 days for dicamba). Glyphosate resistant weeds and the difficulty in controlling more mature weeds underscore the need to scout fields earlier and use some alternative herbicides in your program.  Always consult the product label for specific instructions.

Planning for Planting Date and Seeding Rate for 2017 Peanut Season in Virginia

There may be more peanut and cotton acreage planted in the V-C region this year than in 2016; and growers may wonder what crop to start planting first and which one last. These are legitimate concerns and we may have, at least in part, answers.

For peanut, mid-May planting seems to carry least risk compared with late April to early May or late May to early June plantings. This is quite common knowledge gathered through extensive research at the Tidewater Agricultural Research and Extension Center in Suffolk VA and Peanut Belt Research Station in Lewiston NC.  However, researchers agree that all depends on the weather. For example, research I did in 2009, a relatively cool and wet year with 17 inches of rainfall from May through the end of August, clearly showed that April 20 planting resulted in a statistically significant yield reduction of 780 pounds per acre in comparison with a May 15 planting. At the state level, average yield in Virginia in 2009 was 3700 pounds per acre, similar with the average yield in 2016. Year 2010 was hot and dry with less than an inch precipitation in June, July and August combined. In this year, state average yield was only 1800 pounds per acre and our results indicated that April 15 planting of Bailey resulted in substantially more yield than late May (May 21) planting. The majority of other peanut commercial cultivars tested in that year responded in a similar way; but there were a few exceptions like Sugg, Gregory, and the runner Georgia 09B, which performed well when planted on May 3, but still low when plated on May 21.  The first two weeks in May (maybe end of April too with good thrips control) may be best for peanut planting if April and May are warm with constant daily temperatures of 65 °F or more, sunny days, and night temperatures of 45 °F or more, and soil has “right” moisture; if moisture is excessive, the soil is probably cool. If April and May are cool and wet like last year, maybe waiting for after mid-May to plant peanut is the best option. Varieties seem to respond differently to planting time, but information on the new high oleic cultivars needs investigation.

In 2011 and 2012, I looked at how combination of planting date, seeding rate and tillage affects peanut yield. Results from these years were also dependent upon the specific weather conditions of each year. Across the state, both years were “good” years for peanut, with state averages of 4100 and 4200 pounds per acre; but in 2011, the hurricane in August dropped 18 inches of water at one time, and weather was considerably warmer than in 2012. In 2011, planting on April 25, May 5 or May 23 did not significantly changed yield, in particular when 5 or 6 seeds per foot-row were seeded. Some yield reductions were observed when only 3 seeds per foot were used. However, in 2012 Bailey yielded approximately 1000 pounds per acre more when planted on May 12 in comparison with April 30 and May 23 or June 1; and yields were about 100 pounds per acre greater in conventional versus strip till.

We concluded that the optimum time for peanut planting in Virginia is May 5 to May 20. Planting early may have lower yields due to thrips damage, and cool and wet soils; later plantings may also drop yield due to poor germination and crop stand; and recommended increase of seeding rate to 5 or 6 seeds per foot when planting outside this time window. More information on this research is here.

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Strip versus conventional till for peanut

Research at the North Carolina State University showed that peanut yields were lower when planted on fine-textured soiled in strip tillage in comparison with conventional tillage.  Yield reduction appeared to be associated with greater pod loss in the digging process for the strip versus conventional tillage. Use of stale seedbeds, by bedding rows without other tillage operations sometime after the harvest of previous crop and 4 to 6 weeks prior to planting peanut, was further proposed as a tillage practice that could alleviate yield reduction due to strip tillage. Research using corn, cotton and grain sorghum as rotation crops showed that, indeed, depending on year and location peanut yielded greater in stale seedbed and strip tilled land versus just strip-tilled soil. For example, in 2006 at Rocky Mount, NC, when soil was bedded and strip tilled, pod yield was 3620 pounds per acre, significantly more than 2570 pounds per acre when peanut was planted directly into stripped soil and crop stubble. However, similar responses were not observed in 2002 at either Lewiston or Rocky Mount; which probably denotes that more research is needed to document if stale beds in crop stubbles and in strip tillage peanut production work. According with these researchers, peanut yield in longer rotations was higher than yield of shorter rotation, but the rotation crop had no effect. The full article is here peanut-notes-2017-no-23-peanut-strip-tilled-into-grain-sorghum-stubble.

Information on the pesticides under European Union scrutiny

The European Union (EU) is reviewing the current maximum residue levels (MRLs) for pesticides, some being used in peanut production. The process started in 2016 and will continue in 2017. As expected, peanut imports in EU may be affected by these changes. I am providing here information on these products (credit David Jordan and American Peanut Council), and I will continue to do so when I have new information. Although under review, please note that not all pesticides may have their MRLs lowered. peanut-notes-2017-no-12-comments-on-pesticides-eu-peanut-imports peanut-notes-2017-no-11-wto-communication-on-pesticides-and-mrls

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Peanut Variety and Quality Evaluation 2016 Report

Growers in Virginia, North Carolina, and South Carolina are always in need for high yielding, disease resistant and early maturing peanut varieties with good grading and processing quality. The multi-state Peanut Variety and Quality Evaluation (PVQE) program evaluates advanced breeding lines from the North Carolina State University and University of Florida breeding programs that can further be released as Virginia-type cultivars suitable for the region. These lines are compared with the current commercial cultivars, ‘Bailey’, ‘Sugg’, ‘Sullivan’, ‘Wynne’, and ‘Emery’ for yield and quality throughout the production region in Virginia, North Carolina and South Carolina. The 2016 report with the agronomic and grade PVQE data is available here :http: //pubs.ext.vt.edu/AREC/AREC-198/AREC-198.html. A summary of the 2014-2016 agronomic and grade performance is presented in the table below. In average of 3 years and five locations each year, ‘Bailey’ produced 4,477 pounds per acre and the crop value was 776 dollars per acre. Some of the new lines, however, significantly exceeded ‘Bailey’ for both pod yield and crop value; lines N11028ol and N12008CLSmT in particular. Unlike ‘Bailey’, which has normal oil chemistry, all the breeding lines tested recently in the PVQE program are high oleic. This means they have over 75% of their oil content made of oleic fatty acid; and this characteristic extends the freshness and shelf life of the peanuts from 4 to 32 weeks.

Summary of peanut 2014-2016 results

Summary of peanut 2014-2016 results

Peanut maturity progress in Suffolk, VA

The peanut maturity progress from Sep 2nd and until now seems to be optimal. Images taken on Sep 2nd and Sep 12 for ‘Bailey’ (Bailey peanut maturity progress in Suffolk), and ‘Sullivan’ and ‘Wynne’ (Sullivan and Wynne peanut maturity progress in Suffolk) peanut cultivars are presented here. Bailey, regardless when was planted May 2nd or June 4th, seems to be ready to dig in 10 to 15 more days. In the past 10 days, Sullivan shows a substantial increase of black and brown pod content, however the pod color spread is highest for this cultivar. This suggests that Sullivan may have two main crops this year, which is not surprising given the drought stress experienced for most part of August. This situation always makes digging decisions difficult, but we will continue to watch the maturity progress for this cultivar and extend the search to other locations than Suffolk. None the less, location and individual field conditions have significant effects on maturity. Under the conditions of 2016, Wynne is behind Bailey and Sullivan maturity wise. The images of podblasted pods suggest that digging for Wynne is expected in 20 to 25 days from Sep 12.  Again,  determining maturity in each field individually is the best method for farmers to determine the optimum digging time. Podblasting clinics, such as the one on Sep 19 planned by the new Extension Agent in Southampton County VA, Ms. Livvy Preisser <livvy16@vt.edu>, should be attended rigorously by peanut growing farmers.

Nodulation deficiency in peanut

Indeed, 2016 was not a good year for effective nodulation and early peanut root growth in the Virginia and Carolina region. The growing season started relatively cool and wet. Under this condition peanut developed only a few roots with a reduced number of nodules. These plants were smaller and less green than “normal” plants in particular when planted in crop residue because this maintained soil cooler and wetter. Figure 1 is an example and shows three peanut plants planted on May 9 and picture was taken on June 25. Two plants at the left are smaller, yellower, and with less root growth and number of nodules. These were planted in sorghum residue. The plant at the right is bigger, greener, and has more roots and nodules, but was planted in cultivated and sandier land.

Smaller and yellower two plants at the left are due to poorer nodulation than for plant at the right, even though planted at the same time.

Smaller and yellower two plants at the left are due to poorer nodulation than for plant at the right, even though planted at the same time.

What can be done to prevent poor nodulation, then? One very important thing is to inoculate at planting. But even then, in cool and wet soil roots grow slow for fast inoculation and Bradyrhizobium bacteria may die in absence of oxygen if the soil is too wet. Ammonium sulfate can be used up to 150 pounds of nitrogen per acre, which is about 714 pounds of ammonium sulfate per acre. Usually at beginning flowering poor nodulation will show up in yellow and smaller plants, and right then inorganic nitrogen needs to be applied. The sooner, the better.

It is, therefore, important to scout not just for disease and insects but also for the number and size of the nodules in the first 45 days after planting. To establish a threshold of nodules a farmer should look for during this time, my program has found that after two weeks after planting an average number of 5 big nodules on the main root is to be expected; at 30 days, 70 nodules of any size on the main and lateral roots; and about 130 at 45 days after planting.

Restriction to fungicide use that concerns peanut shellers

I was recently made aware of a long list of fungicides involving the European Union and their restriction on some chemical residues on peanuts. Over the last couple of weeks there were rumors that these restrictions have been relaxed but apparently these rumors are unfounded, I was told. Well, for the industry that exports peanut this is quite serious because any trace of any of the chemical on that list may result in failure to their business. The list includes many fungicides for bacterial diseases, which are not a common problem in the VC region; others, however, like Tilt Bravo SE are. For the sake of staying informed and alerted at what it is and what may come, here I provide that list, with the recommendation that growers do not use any product on that list. Notice to Growers – Products Not To Be Used