{"id":463,"date":"2020-03-10T13:03:46","date_gmt":"2020-03-10T17:03:46","guid":{"rendered":"https:\/\/site.extension.uga.edu\/benhillcoag\/?p=463"},"modified":"2020-03-10T13:03:46","modified_gmt":"2020-03-10T17:03:46","slug":"2020-peanut-seed-quality-seed-treatment-issue","status":"publish","type":"post","link":"https:\/\/site.extension.uga.edu\/benhillcoag\/2020\/03\/2020-peanut-seed-quality-seed-treatment-issue\/","title":{"rendered":"2020 Peanut Seed Quality, Seed Treatment Issue"},"content":{"rendered":"\n

We have received many\nquestions in recent days pertaining to the quality issues facing our peanut\nseed supply in 2020 and relative performance of seed treatments Dynasty PD and\nRancona.  Below is the information that\nyou need to know now; as more information is developed we will pass it to you\nquickly.  As you know, Rancona and\nDynasty PD both contain several fungicides; however they do not contain the\nsame fungicides.  This is noteworthy in\n2020 when Aspergillus flavus<\/em> seems to\nbe especially important.<\/strong><\/p>\n\n\n\n

  1. We have multiple years of data showing that\nDynasty and Rancona are both very good seed treatments for peanuts.  <\/li>
  2. There has been a tendency for Rancona being\nstronger on Aspergillus than Dynasty. \nThis was with Aspergillus niger<\/em>\nwhich has been our primary seed pathogen in recent years.  <\/li>
  3. UGA grad student Brian Jordan’s work showing\nthat the mutation for high level resistance to QoI’s can occur in A. niger<\/em> supports the clearly reduced\nefficacy of azoxystrobin (Abound) in furrow, and also on seed (although\nfludioxinil in Dynasty on seed would help moderate that effect).  <\/li>
  4. Those differences in control may or may not\nhave been enough to make a difference in yield, although the pattern was there\nfor that in some trials<\/strong><\/li><\/ol>\n\n\n\n

    The biggest issue we face with seed quality in 2020 is that\nthis is a different scenario with Aspergillus\nflavus<\/em> (a related, but different, pathogen).  <\/p>\n\n\n\n

    Here is what we know\nnow:<\/strong><\/p>\n\n\n\n

    1)  Last season was\nextremely hot and dry.  There is a much\nhigher frequency of Aspergillus flavus<\/em>\nin our peanut seed from last year than we usually see.  A. flavus<\/em> produces\naflatoxin, but it can also be an\nimportant seedling pathogen.<\/strong><\/p>\n\n\n\n

    2)  Culturing the\npathogens from seed shows a huge difference in the efficacy of Dynasty and\nRancona on this seed borne A. flavus<\/em>,\nat least in some seed lots which were identified as being of lower germination.  <\/p>\n\n\n\n

    3) Rancona has considerably less incidence of A. flavus<\/em> growth in these seed\nlots.  The difference in seed treatments\nfor inhibition of A. flavus<\/em> is\nbelieved to help explain some of the differences in germination observed, with\nRancona producing significantly higher germinations.   Again,\nthis is on some seed lots and not others.<\/strong> \nPreliminary evidence is that the later-harvested seeds, which were\nexposed to the most heat and drought, are the most likely to have high\nAspergillus levels.
    \n<\/strong><\/p>\n\n\n\n

     What does all of this mean?<\/strong>  Are the differences observed this year due to\nA. flavus<\/em> being resistant to QoI\nfungicides as sometimes occurs in A. niger? \nThat issue is not known, but is being evaluated as quickly as\npossible.  There is much we still need to\nlearn, but for now we can say the following:<\/p>\n\n\n\n

    1.  Rancona\nand Dynasty have both been very good seed treatments.  This year, with the emergence of A. flavus<\/em>, Rancona will probably be more\neffective treatment on those lots with elevated A. flavus<\/em> populations. \n(Elevated A. flavus<\/em>\npopulations seem to be linked to seed lots with lower germination).<\/li>
    2. High quality seed with similar germinations\non the Rancona and Dynasty will probably be fine with either product as the\nseed treatment.<\/strong><\/li>
    3. Either\nseed treatment will likely benefit from the addition of an in furrow\nspray.  Proline and Velum Total have been\nthe most consistent in recent years.  \nAbound should not be paired with Dynasty, as it duplicates the chemistry\nmost prone to resistance.  Abound would\nadd an additional chemical class where Rancona is being used, and may help with\nother seed pathogens other than QoI-resistant Aspergillus.<\/li>
    4. If\nseed that is to be planted has (or is suspected to have lower germination\nrates), and the seed has been treated with Dynasty PD, then there is a greater\nneed to consider use of additional infurrow applications of Proline or Velum\nTotal to protect stands.<\/li><\/ol>\n\n\n\n

      NOTE: We cannot\nbecome too narrowly focused as many different pathogens can affect peanut seed!<\/strong><\/p>\n\n\n\n

      Research (including grow out tests in the greenhouse) is\nseeking to answer more of these questions prior to planting season, and we will\nkeep you updated as those results come in. \nIt should be noted that these\nissues are being seen in commercial seed that have been produced, handled and\nstored with great care.  Farmer saved\nseed are sometimes exposed to less than ideal conditions, and may have even\nmore issues this season.<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

      We have received many questions in recent days pertaining to the quality issues facing our peanut seed supply in 2020 and relative performance of seed treatments Dynasty PD and Rancona.  Below is the information that you need to know now; as more information is developed we will pass it to you quickly.  As you know, […]<\/p>\n","protected":false},"author":234,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-463","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/posts\/463","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/users\/234"}],"replies":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/comments?post=463"}],"version-history":[{"count":1,"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/posts\/463\/revisions"}],"predecessor-version":[{"id":464,"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/posts\/463\/revisions\/464"}],"wp:attachment":[{"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/media?parent=463"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/categories?post=463"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/site.extension.uga.edu\/benhillcoag\/wp-json\/wp\/v2\/tags?post=463"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}