19 Mar Agronomy Update – March 19th, 2024

Posted at 16:31h in Recent News by

Hi everyone,

We’re finally getting close to the end of “meeting season.”  I know that it’s a lot of meetings/conferences/workshops…but I hope that many of these events held value for you.

Speaking of which, if you attended any of the AIM Local Workshops in Jan/Feb, I would appreciate if you take the following very short survey on Survey Monkey to let us know what you thought, and what topics you would like us to focus on in the future.

Hollow Heart:

Everywhere I go this winter, growers are talking about hollow heart.  We definitely saw higher than normal levels of hollow heart in 2023 in some varieties.  Hollow heart is a physiological disorder which can be a bit mysterious, but the literature suggests that the main factors influencing development of hollow heart are:

  • Excess soil moisture, particularly at tuber initiation and at tuber bulking. A review from Idaho suggested that fields at 85% or higher of field capacity for water are at higher risk of hollow heart, especially if they remain waterlogged for extended periods of time.
  • Excess nitrogen or uneven nitrogen availability. A number of studies in multiple regions have shown that higher N rates are usually associated with higher levels of hollow heart.  A study in Idaho showed that hollow heart incidence was lower when N was split applied than applied all pre-plant or at planting.
  • Cold soil temperatures (less than 60 F) at tuber initiation, followed by rapid increase in soil temperature. This seems to be more associated with brown center (which can accompany hollow heart), but it repeated cited in hollow heart review articles.

Factors which might be involved but may vary by region or where the literature is less conclusive:

  • Soil calcium levels. Ca is associated with cell wall development and tuber quality and low Ca levels are mentioned in several papers as a potential risk of hollow heart.  At the same time, there are few papers that show any benefit at field scale from Ca addition in reducing hollow heart.  It may come down to whether a field or region has a true calcium deficiency.
  • Foliar boron. Again, the literature is mixed on the impact of foliar boron on hollow heart.  A study in Idaho found no improvement in hollow heart with use of boron.  Conversely, a 2019 study in Maine saw a reduction in hollow heart in 10 oz size potatoes from 42% to 16% with used of 1 L/acre of foliar boron.  More work on this is likely needed in a PEI context in order to better understand function.
  • Seed spacing. In Russet Burbanks, tighter seed spacing and a smaller proportion of tubers under 10 oz has been shown to help mitigate the risk of hollow heart.  In some of the newer varieties that already have tighter seed spacing, we may need to further investigate the role of seed spacing on tuber number and hollow heart.

So, what can we do to help reduce the risk of hollow heart?  Here are a few things that we can look at:

  1. Avoid over-application of nitrogen. Make sure that you are taking into account nitrogen credits from organic matter, manure or previous year legumes when determining applied N rates.  Higher OM fields, fields with a history of manure application, and fields that had clover or alfalfa the year before will have more N available during the season, particularly later in the season as that N mineralizes.
  2. Use enhanced efficiency N products. Having less of your N available all at once has also been shown to decrease the risk of hollow heart.  In addition to the sustainability benefits, there may be a benefit to reducing hollow heart by using more of these products.  Split application (top-dressing, foliar application) may also be a tool.
  3. Improved drainage/Avoid planting wet spots. Pull the planters up in the parts of the field that are usually wet.  In a year where they don’t drown out, they may still cause you a headache with hollow heart.  Mitigating compaction or installing tile drainage may also help with improving the rates of water infiltration, reducing waterlogging in fields.
  4. Tighter seed spacing. Particularly for varieties like Russet Burbank and Mountain Gem, tighter seed spacing and reducing the percentage of large tubers may help with reducing hollow heart incidence.
  5. Foliar boron. As noted, we need more information on this as a beneficial practices; however, there are a number of positive anecdotal accounts from growers who used foliar boron and had lower hollow heart in 2023.  Particularly for vulnerable varieties, this is likely worthy of further investigation.

 

SpudChat is Back!

My SpudChat podcast is back with a new episode this week, after a bit of an extended hiatus.  This week’s episode is with Dr. Mark Stalham of the United Kingdom.  I talk to Mark about the state of research in Britain, the challenges faced by British potato growers, and how they are meeting those challenges.

SpudChat is available at https://spudchat.buzzsprout.com/ or wherever you regularly download your podcasts!

 

Videos from Potato Expo / Chad Berry Meetings:

Videos from the International Potato Tech Expo Conference as well as our AIM Workshops with Chad Berry are available on the PEI Potato Agronomy Site under Seminars/Workshop Presentations.  Thank you to all who attended these sessions…I hope that you found value in them or can take the time to watch the videos when you have a free moment.

 

Seed Handling/Seed Cutting BMPs:

Some folks are in the process of taking home and grading seed already.  We have a pile of good seed management factsheets, presentations and research reports on the Agronomy Site, including an updated factsheet on seed handling that I put together last spring.  Reiterating what Rebecca put out in her email to growers earlier today…make biosecurity a priority for receiving, cutting, and transporting seed.  Make the extra effort to ensure that all cleaning and disinfection is performed, and keep good records of what activities you have performed.

 

Special Notice on Seed Movement

Please be mindful of the stated regulations for Records of Bulk Movement (RBM).

A RBM must accompany each shipment* of seed potatoes at the time of movement.

*Shipment means the movement of one lot, or any part thereof, of seed potatoes to a single consignee. Ie: RBM sent with first truckload

Non-compliance may result in decertification.

CFIA Seed Regulations: https://laws-lois.justice.gc.ca/eng/regulations/c.r.c.,_c._1400/page-6.html#h-510924

 

I’m going to be at the Northeast Potato Tech Forum the next couple of days, learning about the wealth of potato-related research happening in our region.  Thank you to the rest of the NEPTF committee for their help in putting this event together.

Have a great rest of the week

Ryan