Chlorosis

Plant and Animal Nutrient. Copper is one of seven micronutrients that has been identified as essential to the proper growth of plants (87). Cereal crops are by far the most affected by copper deficiency (see Wheat and other cereal grains). Greenhouse studies have shown yield increases from 38% to over 500% for wheat, barley, and oats (88) using copper supplementation. A tenfold increase in the yield of oats was reported in France (89). Symptoms of copper deficiency vary depending on species, but often it is accompanied by withering or chlorosis in the leaves that is not ammenable to iron supplementation. In high concentrations, particularly in low pH sods, copper can be toxic to plants. 

Sulfur dioxide Bleached spots, bleached areas between veins, chlorosis insect injury, winter and drought conditions may cause similar markings Middle-aged leaves most sensitive oldest least sensitive Mesophyll cells 0.3 785 8 hr... 

Chlorosis and abscission brown spotting yellowing of veins... 

Injury any physical or biological response to pollutants, such as a change in metabolism, reduced photosynthesis, leaf necrosis, premature leaf drop, or chlorosis. 

Grtin-spat, m. a variety of diopside. -star, m. glaucoma, -stein, m. (Geol.) greenstone, -stich, m. greemsh tinge or cast, -stift, m. green pencil, -sucht, /, chlorosis. 

Unlike carboxylic acids, the release and also the production of phytosidero-phores in roots of both Al-sensitive and Al-tolerant wheat cultivars was rapidly inhibited in response to Al treatments and seems to be responsible for Al-induced iron chlorosis in wheat (257). 

Y. C. Chang, J. F. Ma, and H. Matsumoto, Mechanisms of Al-induced iron chlorosis in wheat (Triticum ae.stivum). Al-inhibited biosynthesis and. secretion of phyto-siderophore. Physiol. Plant. 102 9 (1998). 

A. A. Mohamed, F. Agnolon, S. Ce.sco, Z. Varanini, and R. Pinton, Incidence of lime-induced chlorosis plant re.sponse mechanism and role of water soluble humic substances. Agrochimica 42 255 (1998). 

E. Jurkevitch, Y. Hadar, and Y. Chen, Involvement of bacterial siderophores in the remedy of lime-induced chlorosis in peanut. Soil Sci. Soc. Am. J. 52 1032 (1988). 

A. Mozafar, F. Duss, and J. J. Oertli, Effect of Pseudomonas fluorescens on the root exudates of two tomato mutants differently. sensitive to Fe chlorosis. Plant Soil 144 161 (1992). 

The tables show that the fronds treated with extracted materials exhibited bleaching, chlorosis, and other morphological changes. 

Results presented in Table VII show that sufficient light is needed for new shoot formation on explants and that the herbicide fluridone causes chlorosis in new growth just as in whole plants (12,13). These data also confirm that the apical explant, which contains the terminal meristem, is a poor system for assaying inhibitors of new shoot production. 

Hydrilla explants responded to herbicides essentially the same as whole plants fluridone caused chlorosis in new shoots. 

In addition to reduction in root length, seedlings exposed to all concentrations of polar peak 1B displayed both an increase in root hairs and chlorosis at the tips of the cotyledons. The severity of these symptoms increased with the dosage. 

Increased yields of various crops occur when copper salts are added to fertilizers at 300 to 800 mg Cu/m3 (NAS 1977). In com (Zea mays) and other vegetables, younger plants are more sensitive to copper deficiency than mature plants in all cases, copper-deficient vegetables show chlorosis, reduced growth and reproduction, and low survival (Gupta 1979). 

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