At XiteBio, we love interacting with our customers and enjoy addressing any and all questions they may have for us about inoculants and biologicals. With warm spring weather finally arriving growers are starting to put seed in the ground, and with seeding comes questions about applying inoculants and biologicals. Questions like how do I apply inoculants? When should I apply? And how should I care for my seed after inoculant application? Are commonly sent our way this time of year and we are always happy to address them. In this week’s edition of Growing Possibilities, we will be addressing all these questions and more by discussing the ins and outs of applying inoculants and biologicals to your crops.
Legume growers should all be familiar with rhizobial inoculants, and when it comes time to inoculate your legumes with nitrogen-fixing rhizobia there are two methods you can use: on-seed or in-furrow.
On-seed application means the inoculant is applied directly to the seed, often simultaneously with other seed treatments. Sometimes the grower themselves applies inoculant on-seed, but often growers will buy pre-inoculated seed from a seed dealer that has already been treated with a rhizobial inoculant. If you are applying an inoculant on-seed, you need to ensure that your inoculant is compatible with any other treatments you will be applying, or the effectiveness of the inoculant could suffer. Seeds treated with inoculant before planting need to be planted within the on-seed window stated by the manufacturer of your inoculant. The on-seed window is the period of time after application of your inoculant within which the treated seed must be planted in soil. Whether you are applying inoculant yourself or buying pre-treated seed, it is important to remember that inoculants contain living bacteria, and that the same storage instructions on the packaging still apply after application onto seed (i.e. do not freeze, do not leave in direct sunlight, etc.). Manufacturer storage instruction for your specific inoculant should be followed until the seed is in the ground (1).
In-furrow application refers to the application of inoculant directly into the seed trench. If you apply in-furrow, be sure to cover the seeds with soil as soon as possible after applying the inoculant, as exposure to sunlight and wind can harm the bacteria you just put in the ground. Just like with on-seed application, you must ensure your inoculant is compatible with any other crop input you are applying at the same time. In-furrow inoculation rates can vary depending on your row width, so make sure you consult your inoculant manufacturer’s recommended rates before applying.
Both of these methods are effective at delivering an effective amount of inoculant to your crop, but there are slight differences in nodulation between the two. With on-seed inoculation, nodules are more prevalent at the crown of the root system, while nodules will be more prevalent on lateral roots with in-furrow inoculation. Sometimes an application of both on-seed and in furrow is advantageous. This is called dual inoculation and it can give your soil rhizobia populations an extra boost when planting on virgin legume acres or in fields without an existing population of the bacteria you are applying (2).
There is more to Plant Growth Promoting Rhizobacteria (PGPR) than just rhizobial inoculants for legume crops. There are biological crop inputs for almost all conceivable crops, with PGPR biologicals offering advantages like phosphorus (P) solubilisation, sulphur (S) oxidation, iron (Fe) chelation, phytohormone production and more. Application for products like this can vary, so let’s take a look at XiteBio’s liquid PGPR biological XiteBio® Yield+ as an example. The bacteria that make up the active ingredient in XiteBio® Yield+ are motile, which means they can move through the soil to find their target (plant roots). For XiteBio® Yield+, the options for application are in-furrow or post emergent spray. In-furrow application follows the same method as previously discussed, with the need to cover your seed as soon as possible after application being just as important.
Post-emergent application refers to applying your biological after the seedlings have emerged a few weeks after planting. A common method for applying Yield+ this way is mixing it in a tank-mix with other post-emergent crop inputs such as herbicides, etc. If you are applying as part of a tank-mix, be sure to check that your biological is compatible with any other products in the tank. If you are applying after your plants have emerged, be sure to do it within the manufacturer’s recommended time frame, the earlier the better as applying too late can diminish what the bacteria in your soil can accomplish during the season. The condition of your field is also important to check before applying biologicals in a foliar spray. Too much debris on your field can prevent the bacteria in the biological from reaching the soil and ultimately from reaching your plant’s rhizosphere. For XiteBio® Yield+, we recommend no more than 25% ground cover in your field if applying post-emergent.
Hopefully we have addressed a few questions you may have had in mind about how to get the best results from your biological crop inputs. If you have any other question about inoculants or biological crop inputs in general, don’t hesitate to contact us! To learn more about our line of inoculants and biologicals, visit our website at www.xitebio.ca.
References:
2) https://saskpulse.com/files/technical_documents/190408_Inoculant_Options_for_Pulse_Crops.pdf