Research data, such as those here Seeding Rate-May 2018, showed that saving seed at planting does not return high yields or economic profit. To achieve high yields, we recommend planting 5 or 6 seeds per foot of row, assuming a germination of 80% and above. This is in particular necessary for large seeded cultivars like Emery and Wynne, and under irrigation. If germination is lower than 80%, which may be the case this spring for some seed lots of Wynne and Sullivan, 6 to 7 seeds are safe to plant but nothing above that. At least, we have not recently tested or heard of a benefit to increase the seeding rate above 7.
There are concerns that imidacloprid-based insecticides for thrips control may negatively affect Rhizobia in inoculants when tank-mixed and applied in the furrow when plating peanut. As we are just a week (or less) from starting peanut planting in Virginia, I thought this issue be addressed for the farmer’s peace of mind if they decide to mix Optimize Lift inoculant with Admire-Pro insecticide for in-furrow seed treatment. I personally have not looked into this issue before, because we have not seen any effects in research plots or received complaints from farmers. However, we will research this aspect in 2018.
Meanwhile, colleague Dan Anco, Peanut Specialist at Clemson University, tested the effect of different tank-mixtures for in-furrow applications on the nodule number and peanut yield in 2015 and 2017. Graciously, Dan shared this information included in the In_furrow tank mixes tables. The results clearly show no effect of mixing Optimize Lift with Admire-Pro on peanut yield in both years (Tables 1 and 2), even when the number of nodules from this mixture appeared to be reduced by the use of Admire-Pro in 2017 (Table 2). David Jordan, Peanut Specialist at North Carolina State University, reported similar findings Peanut Science Inoculant CFTGM Peanut Inoculant.
The 2017 PVQE agronomic and grading results are available here https://pubs.ext.vt.edu/AREC/AREC-231/AREC-231.html. In 2017, 25 peanut breeding lines from the North Carolina State University’s Peanut Breeding program were tested and compared with five commercial cultivars at five locations in Virginia, North Carolina, and South Carolina. At two locations, two digging dates were performed, bringing the number of testing environments to seven. Data include the 2017 released cultivar ‘Bailey II’ tested as line ‘N12008olCLSmT’. Bailey II is a Virginia-type line derived by backcrossing the high oleic seed oil trait patented by the University of Florida into the cultivar ‘Bailey’. Bailey II has approximately 44% jumbo and 43% fancy pods, and seeds with tan seed coat averaging 600 seed lb-1. Bailey II is partially resistant to three of four major regional diseases: leaf spot, Sclerotinia blight, and Tomato Spotted Wilt virus, but it should be considered susceptible to Cylindrocladium black rot. Bailey II has bright pods and flavor comparable with runner-type standards. Yields and the number of days to maturity are similar with Bailey (145 days). In PVQE trials, Bailey II out yielded the popular Bailey in all years of testing.
The 2018 Peanut State Production and Marketing meeting will be held at Paul D. Camp Workforce and Development Center, Franklin, VA, on February 14. Here the program is available. Agenda for the peanut meeting Please make sure to attend this meeting offering important updates on agronomy, varieties, and pest management that will help growers make research based decisions for a successful 2018 peanut growing season.
Looking forward to see you there.
American Peanut Research and Extension Society (APRES) will held its annual meeting and the 50th anniversary at the Doubletree Hotel in Williamsburg, VA, during July 10 through 12. The “Early Bird” Registration fee is $250 for members; spouses and children attend free. APRES has secured a group hotel rate of $129/night and a few per diem rooms at $91/night. The registration and the official call for papers are open, and complete details can be found on the APRES website www.apresinc.com.
As every year, Bayer CropSciences is sponsoring the Peanut Education for Excellence Program as part of the American Peanut Research and Education Society (APRES) annual meeting. They also fully fund the participation of one Agent at the annual meetings. The agent will have to submit an abstract and make an oral presentation in the Extension/Education section of the meeting about extension and technology transfer programs implemented for peanut production in their counties. The deadline for abstract submission is March 31. In collaboration with the VA Peanut Board, I will continue to explore more funding opportunities to increase Agent participation at this important research and education meeting on peanut production.
I encourage all Extension Agents with peanut responsibilities to use this opportunity and participate at the 2018 APRES meeting.
According to the weather recordings (http://webipm.ento.vt.edu/cgi-bin/infonet1.cgi), the heat units received by peanuts grown in Virginia from May 1 through September 5 are in average 2370 °F. There are, of course, location variations. For example, in Suffolk total heat units from May 1 is 2566 °F, in Southampton 2314 °F, Greensville 2480 °F, and Waverly 2123 °F. The current Virginia type commercial cultivars predominantly grown in Virginia require in average 2650 °F to optimum maturity. With a daily average of 70 °F recorded in the past week, optimum maturity seems to happen in the next day and a half to 7.5 days. However, would it?
Probably not, and the pictures below prove it. Today, Sep 6, we determined the maturity of four cultivars, Bailey, Sullivan, Emery and Wynn, planted in Suffolk on May 3. Based on the mesocarp color, when laid on a color maturity chart, it seems that a minimum of 20 to 24 days are still needed to reach the optimum digging for this location and the current season. In average, cultivars only have 1% of black pods, 14% brown, 20% orange, 44% yellow and 22% white.
Pod blasting demonstrations will take place this week Friday, September 8, at the Southampton Fairgrounds from 8:00 AM to noon. It will be a repeat at Indika Farms in Windsor on September 14; times will have to be determined, but probably also in the morning. See you there with your peanut samples to be pod blasted!
According with the FSA, 26,323 acres of peanut were planted this year in Virginia; and the crop progresses well so far. The early May planted peanuts are getting close to the full seed growth stage (two pictures of peanut pods and seed are provided here)
However, in some sandy fields plants have become yellowish lately. It is difficult to guess the reason for the yellow color. It could be caused by poor inoculation or nitrogen fixing due to drought or water standing; manganese deficiency, which is relatively easy to identify (a picture of manganese deficiency is provided here)
; but also acidic soils, which are predominant in south-eastern Virginia. Soil pH directly affects plant growth through its effects on the availability of all nutrients. For example, soils with pH less than 6 may become deficient in calcium, magnesium, phosphorus, potassium, and molybdenum. Molybdenum is essential in biological nitrogen fixation and, even though the nodule numbers may seem sufficient, the result, tissue nitrogen content, may be limited. Gypsum does not alter soil pH; only lime can be used for that, and dolomitic limestone is the desired product as it provides calcium and magnesium. The traditional recommended pH range for peanut land is 5.8 to 6.2, but more towards 6.2 when Virginia-type peanuts are planted. In addition, limestone moves very slowly into the soil, therefore applying limestone early in the planting process and tilling it into the root zone (top 7 inches) is important. Rainfall amount, application of fertilizers containing ammonium or urea, sulfur containing ingredients, and decomposition of organic matter (previous crop residue) also adds to soil acidity. Soil sampling should be taken in the fall and, if the test results indicate a need for limestone, for best results it should be applied in the fall or winter months. If applied just prior to planting and soil is dry, lime will have little effect on the pH.
Going back to the yellow plant color, the best approach for knowing and not just guessing what causes it is to take soil and tissue samples and send to a laboratory for determining the soil pH and tissue nutrient content. The table below shows the sufficiency levels for macro and micronutrients of the peanut vines. It is recommended that 50 whole shoots throughout the field, or problematic areas, should be combined in one sample prior to or at bloom stage.
|Nitrogen (N)||3.50-4.50||Iron (Fe)||60-300|
|Phosphorus (P)||0.25-0.50||Manganese (Mn)||60-350|
|Potassium (K)||1.70-3.00||Boron (B)||25-60|
|Calcium (Ca)||1.25-2.00||Copper (Cu)||5-20|
|Magnesium (Mg)||0.30-0.80||Zinc (Zn)||25-60|
|Sulfur (S)||0.20-0.35||Molybdenum (Mo)||0.10-5.00|
Manganese (1 pound per acre) and boron (up to 0.5 pounds per acre) are regular applications in peanut production during summer, but nitrogen can also be applied if the tissue analysis indicates the need. Rate of 60 to 120 pounds per acre elemental nitrogen (or 285 to 571 pounds per acre of ammonium sulfate) can be applied, depending on the test results; and it is worth applying even at this time (August). After all, there are two more months of peanut growth. Increasingly more fields seem to require potash applications. Peanut is efficient at scavenging phosphorus and potassium left in the soil from previous crops, but for some reason potassium is getting slim each year. An application of 100 pounds per acre of potash may correct that deficiency.
Knowing the history of each field for yield and crop growth, can help to anticipate where nutritional problems may occur and allow for preventive measures even before symptoms are visible. Drone technology can be used to derive soil maps for pH, moisture and yield of each crop in rotation, so that precise locations within a field where problematic spots exist can be known and independently managed using the variable rate technology (VRT). The VRT consists of a control system on an application equipment, planters, sprayers, and spreaders, which allows grower to achieve site-specific application rates of inputs. To work, prescription maps need to be generated and uploaded to the computer within the machine cab that has the VRT. Drones can be used to generated these maps. For example, the last picture in this story shows an image of the soil moisture distribution of a field at the Tidewater AREC. The image was taken before peanut planting with an infra-red camera on a drone; the drone purchased not long ago with funding from the Virginia Peanut Board, the shellers, and Virginia Crop Improvement Association. In the image, the darker the blue the more soil water was available; green color indicated dryer soil sections with the driest spots being colored in yellow and red and located in the patches adjacent to the field.
Potential applications of this technology can help growers to use variable seeding rates and depths depending on the available soil moisture at planting, and monitor irrigation needs throughout the growing season.
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.
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.
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