Published on Thursday, March 16, 2017
The buttercups on my front walk are already blooming, the geese on the lake are pairing up, and every farmer I talk to is already getting antsy about planting. While the buttercups might have gotten a little ahead of themselves in light of this week’s cold snap, spring is inching ever closer. It’s a time of new life and renewal, manifested in the return of green to our fields. This all gets me thinking about seeds.
This time of year is also shipping season here at Beck’s. In Atlanta alone, we have 12 acres of warehouse to store the seed before it is shipped out to farms across the Midwest. When I lead tours through the seed processing tower, I think about how each individual corn seed rattling across the gravity table holds potential to increase and multiply itself more than 500-fold. It is our job to keep that seed healthy, protect it with advanced seed treatments, and then deliver the seed and all of its potential to the farmer. A seed box of corn contains 3.6 million new opportunities.
We sell a living organism – we can’t just add another shift to increase output. Your planting success in the spring depends on a highly choreographed dance involving producing parent seed stock, allowing cross pollination to occur in a production field, timely harvest and maintaining seed quality through every step of processing. Grain crops in general have an advantage compared to other plants – it’s relatively straightforward to store seeds from fall to spring. Sugar cane or potatoes require storing pieces of the plant itself which are much more likely to spoil and less durable when compared to seeds.
Seeds are quiescent or dormant, meaning that they are in a sort of suspended animation awaiting the right conditions for emergence. Seeds can be incredibly patient waiting for these conditions. My favorite example is the Methuselah Palm, which was over 2,000 years old when it germinated! That palm seed was stored underground in Israel and was found in an archaeological excavation. Instead of relying on dumb luck like in the case of the Methuselah Palm, modern botanists have invested in long-term seed storage facilities where biodiversity is preserved at low humidity and low temperature to prolong viability. The largest seed storage facility in the US is the National Seed Storage Laboratory in Fort Collins, CO, and the Svalbard Global Seed Vault maintains the UN’s germplasm collection. These collections will be useful in case there is a widespread disaster and agriculturally important species go extinct. The Svalbard facility is situated inside a glacier on an island in Norway near the North Pole so that if it loses power, the seeds are maintained in a cold, low humidity environment. We don’t need a nuclear fallout-proof bunker to store Beck’s seed because we are constantly releasing new genetics. Seeds sold only five years ago wouldn’t be competitive with today’s higher yielding, improved genetics so long-term storage isn’t a problem.
So how does a seed “know” it’s time to germinate? There are a number of different cues from the environment. Temperature is a big one. That’s why planting into cold soil is a challenge. In cold soil, the plant develops more slowly – paving the way for yield robbing fungi, bacteria and insects to attack the young plant. Beck’s Escalate™ yield enhancement system helps to defend the young plant and get it off to a good start.
Access to water and air come next. The first step to germination is the seed imbibing (absorbing) water. Water reactivates enzymes within the seed – enzymes that move starch from storage into active use by the baby plant. Then the plant needs air to fuel cellular respiration. Most seeds will not germinate if they are saturated in water or will quickly succumb to rotting organisms in the soil. Seeds need to have a balance of air and water for proper emergence. If you ever make black beans from dried beans for Taco Tuesday, you’ve seen how a seed will absorb water. If you get too busy (or forget) and leave those black beans sitting in a little water for a few days, you’ll end up having bean sprout by Friday (happened to a friend…).
Seed to soil contact is also a big talking point each spring. The soil structure, pre-plant tillage system and planter set up ensure that the seed physically touches soil. That physical contact is how the seed imbibes water. If the seed is suspended in the planting trench, it might only be touching soil on the sides, with voids above and below the seed. That spells trouble for successful germination. Our Practical Farm Research (PFR)® team’s closing wheel study shows the importance of having the right set up on your planter in the spring (pages 58, 124, 270, and 327 in the PFR book) for optimal seed to soil contact.
Plants immediately start putting down roots. The nascent root, the radicle, is the first structure to emerge from the seed. A phenomenon called gravitropism means that plants sense gravity and “know” which way is up. This sense of gravity is how seeds put leaves up and roots down without regard to the orientation of the seed as it falls out of the planter. NASA recently learned on the International Space Station that Earth’s gravity isn’t the only force telling roots to grow away from the shoot of the plant, but it plays a major role. Roots, even small ones, allow seeds to access even more water. As the plant grows, each cell fills up with water and physically increases in volume. This allows the plant to start lifting soil out of the way as it drives toward the sunlight. Damage to the early root system can be very detrimental to plant establishment. Once the early leaf finally breaks through the soil surface, it can begin to acquire new energy from photosynthesis.
Anyone who has taken a careful look around in the springtime knows that corn and soybean plants have different strategies for emerging from the soil. Corn looks like a tiny spear when the coleoptile first emerges (here’s a time lapse video of corn emerging).
The energy reserve for the young plant stays safely underground. Soybeans use brute force to haul the entire seed out of the soil (here’s a great time lapse video of a bean plant emerging).
The young soybean plant’s energy reserves are in the seed leaves or cotyledons, which is why frost can be particularly damaging to young soybeans. It’s hard work to push the cotyledons through the soil surface, a task that can be made more challenging if there is a crust on the soil surface.
Once the roots are mining the soil and leaves are stretching up into the sunlight, it is off to the races and the plant will do everything in its power during the growing season to take over the world. Bigger leaves, more height, larger root system – curtailed only by the genetic blue print and resources supplied by the environment. All of this work is done for the sole purpose of more seed.
Author: Samantha Miller
Categories: Ag Education
Tags: Beck's Blog, Beck's Hybrids, corn seed, Daffodils, soybean seed, Samantha Miller, seeds, National Seed Storage Lab, why seeds matter