Hands-On Agronomy by Neil Kinsey & Charles Walters

Author:Neil Kinsey & Charles Walters [Kinsey, Neil]
Language: eng
Format: epub
Publisher: Acres U.S.A.
Published: 2015-01-22T05:00:00+00:00

Potassium is the first key for stalk strength, but the crop also has to have enough copper and manganese. Also, mineral interrelationships can underwrite problems because of the complex ways nutrients work in a soil system.

There are interrelationships between all the different elements in the soil, as illustrated above. Follow each line to see the interrelationships. Look at sodium and potassium. The only line that goes from sodium is to potassium. It doesn’t go to any other mineral. The only relationship to be concerned about in terms of sodium is the sodium-potassium relationship. When the potassium and sodium base saturation percentages total above 10%, the plant is not going to get as much manganese. It isn’t a matter that the manganese is tied up. The soil test may show excellent manganese levels. It is simply a matter of a combined 10% saturation of potassium and sodium blocking manganese uptake from the roots. If you have 6 or 7% potassium, at that point you should become especially watchful concerning the potassium-sodium percentages.

Any time you have sodium in a field and the percentage saturation of sodium is higher than the percentage saturation of potassium, you already have trouble if you experience both heat and humidity at the same time. When sodium exceeds potassium in the soil, the plant will take the sodium instead of the potassium. Plants do not distinguish between the two. As long as the plant is getting potassium, it incorporates potassium into the cell wall. But the day the percentage of sodium exceeds the percentage of potassium in the soil, adequate potassium stops getting in and sodium is incorporated into the cell walls instead. As long as it stays nice and cool everything works—or as long as the humidity is low this is no problem. So in various parts of the world, they hardly recognize this problem if it ever surfaces. However, when it gets hot and humid, the sodium incorporated into the cell walls begins to cause expansion. When that expansion is too great the cell walls burst, killing the plant cell by cell. This phenomenon shows up easily in peas and beans. It sets the stage for a problem that looks like nematodes, but is not. The lighter the soil, the worse the problem.

Certain farmers and consultants have determined in their minds that if you have nematodes and you apply potassium, you eliminate the nematode problem in your soil. I have clients who have problems with nematodes and they put on plenty of potassium. Where we have nematodes, we never eliminate nematode problems just by putting on potassium. It can make the plant look better and do somewhat better, but the nematode problem stays. You have to use other materials for nematode control. Where we have sodium that is higher than potassium, it can look like a nematode problem. But if you solve the problem by adding potassium and thus building the potassium level above that of sodium, too much sodium in relation to potassium was the problem.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.