Some causes of chlorosis and necrosis of sugar‐beet foliage

Abstract

The symptoms and characteristics of two virus and one fungus disease and four nutritional disorders of sugar beet which cause chlorosis and necrosis of the foliage are described. The causes of the diseases and methods of distinguishing between them have been investigated by analytical, pathological and field experimental methods.Experiments in which diagnosis was confirmed by serological and spectrochemical methods show that the two often easily confused diseases, sugar‐beet yellows virus and magnesium deficiency, can be visually distinguished.Sugar‐beet yellows virus reduces the potassium, but slightly increases the magnesium content of the leaves.Magnesium deficiency symptoms are associated with a low magnesium content of the foliage, but may be induced by salt applications without greatly affecting the magnesium analysis.‘Potash’ deficiency symptoms are often, but not necessarily, associated with a low potassium analysis and may actually be caused solely by a deficiency of sodium. In the field, symptoms are induced by sulphate of ammonia and phosphate applications and may be prevented in some cases by the application of either salt or muriate of potash, in others by salt only. Some interchangeability of the functions of potassium and sodium in the plant is suggested.Manganese deficiency symptoms are associated with a low manganese content of the leaves, which can be readily increased by spraying or injection with manganese sulphate solution, but a high concentration of manganese in the foliage, such as sometimes occurs naturally on acid soils, has a toxic effect.

Controlling manganese deficiency in sugarbeet with foliar sprays

“…Manganese is essential for photosynthesis and is involved in carbon and nitrogen metabolism within plant tissue (Gregory 1971;Terry & Ulhrich 1975). Symptoms of manganese deficiency in sugarbeet in the UK were first described more than 50 years ago by Da vies (1939) and later by Hale et al (1946). Chlorotic symptoms can develop by early May and, unless treated, arc followed by curling of leaf margins and then by necrosis.…”

Can a Low-Dose Selenium (Se) Additive Reduce Environmental Risks of Mercury (Hg) and Arsenic (As) in Old Gold Mine Tailings?

“…The presence of chlorosis in grass seedlings in the untreated and low-Se treatments is unlikely associated with a lack of nutrients in the tailing material (Hale et al 1946). The tailing materials were collected from under a thick humus layer created by decades-old spruce forest which indicates there were sufficient nutrients to support the forest despite the toxic nature of the tailings (it is of note that the understory was observed to be quite sparse in this area relative to neighbouring forests away from the tailings).…”

“…Chlorosis, a condition in which plant leaves produce insufficient chlorophyll, can be in response to insufficient nutrients or toxic conditions (Hale et al 1946;Shaibur et al 2006). The number of grass shoots affected by chlorosis decreased significantly with increased [Se] treatments, with no chlorosis observed for grass seedlings in the 15 mg Se/kg treatment (Table 2 Week Despite the lack of significance in earthworm mortality with soil and plant parameters, it is worth noting that only the earthworms in the untreated 0 mg Se/kg tailing material replicates had observable surface pathologies.…”

Studies in the Diagnosis of Mineral Deficiency: V. Manganese Deficiency in Wheat

“…There is no need to discuss here at length the use of plant analysis for the diagnosis of mineral deficiency, for the subject has been adequately reviewed elsewhere (Goodall & Gregory, 1947 Hale, Watson & Hull (1946) found that the leaves of sugar-beet plants showing symptoms of manganese deficiency almost always had a manganese content less than 25-30 p.p.m. Marsh & Powers (1945) considered IOO p.p.m.…”