Monocotyledonous species, tolerance

Despite increased citrate accumulation in roots of Zn-deficient rice plants, root exudation of citrate was not enhanced. However, in distinct adapted rice cultivars, enhanced release of citrate could be observed in the presence of high bicarbonate concentrations in the rooting medium, a stress factor, which is frequently associated with Fe and Zn deficiency in calcareous soils (235) (Hajibo-huid, unpublished). This bicarbonate-induced citrate exudation has been related to improved Zn acquisition in bicarbonate-tolerant and Zn-efficient rice genotypes (Fig. 9) (23S). Increased exudation of sugars, amino acids, and phenolic compounds in response to Zn deficiency has been reported for various dicotyledonous and monocotyledonous plant species and seems to be related to increased... 

Aryloxyphenoxypropanoates and cyclohexanediones are herbicidal to most monocotyledons but not to dicotyledons. A comparison between a susceptible species, barley (Hordeum vulgare), and a tolerant species, soybean (Glycine max) showed that haloxyfop was effective in reducing lipid biosynthesis in barley but not in soybean leaf discs (Table I). 

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