Effects of potassium nutrition on the absorption of sodium, calcium, and magnesium by intact tomato plants

Tomato plants (cv. VF145 B 7879) were grown in a greenhouse by the water culture technique with six levels of K nutrition. The absorptions of Na, Ca, and Mg were not affected greatly by the K nutritional status of the intact tomato plants, except when the plants were extremely K deficient. The rates of absorption by the intact plants were slow initially when the plants were small, and then increased rapidly as the growth rates increased. At the onset of K deficiency, the rate of growth and water use by the tomato plant decreased. A linear function of water use and plant size was obtained, indicating that water use was a function of plant size and hence a function of the plant's nutritional status. Waterlogging, simulated by aeration cut‐off of the culture solution for two days, had only a small effect on water use, but concurrently interrupted the absorption of K, Ca, and Mg.