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The salt tolerance of crops has usually been studied under optimal fertility conditions. The objectives of the present studies were to compare crop response to salinity when nutrients were limiting, adequate, or in excess to guide proper fertilization of saline soils and to determine whether additional fertilizer could restore yield losses caused by salinity. Corn (Zea mays L.), wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and six vegetable crops were grown to maturity in large, outdoor sand cultures to study the interactive effects of salinity and nutrition. Increasing levels of phosphate (0.1 to 2.0 mM) aggravated salt injury in corn and decreased salt tolerance. Decreasing solution K from 2 to 0.4 meq/liter did not affect leaf K or yield of corn. Deficient levels of P or N did not consistently decrease salt tolerance of any of the crops studied, although the wheat and barley varieties showed erratic decreases in salt tolerance when N or P was deficient. When N or P was severely growth‐limiting, salinity affected growth of some crops [broccoli (Brassica oleracea var. capitata), cabbage (B. oleracea var. botrytis)] less. Conversely, when salinity severely limited growth, nutritional responses of some crops decreased. Salinity did not aggravate N or P deficiency as judged by leaf N and leaf P contents. Effects of salinity and N or P deficiency on other mineral constituents were highly crop specific.

A B S T RAe'!' 13ERXSTI';Il'i, LI,;oN. (D. S. Salinity Lab., Riverside, Calif.) Osmotie adjustment of plants to saline media. II. Dynamic phase. Amer. Jour. Bot. 50(4): 360-370. Illus. HJ63.-The time-course of osmotic adjustment in bean and pepper plants to increased salinity of the medium was determined by periodic sampling of plants following salt additions to the medium. Bean plants adjusted to increases of 1 atrn or within a day, the adjustment in roots occurring primarily at night following salt addition at 6 I'M, whereas leaves and stems made most of their adjustment in the daytime.Pepper plants did not adjust completely to 1.5 atrn Ne.Cl additions in 48 hr, but or increased by about the same amount in both species (0.5-1.0 atm per day). Diurnal fluctuations in OP of leaves and stems of both species and in roots of pepper were matched by parallel fluctuations in K concentrations. Added N aCl caused increased concentrations of K in leaves and stems which were more or less replaced by more slowly absorbed ions, Ca and Mg in bean leaves and Na in bean stems. Other salts produced comparable immediate effects on K level, but K was replaced more rapidly if the cation added was readily accumulated by the bean (Ca). In roots, Na uptake predominated if Na salts were added but K uptake was important on the CaCI, treatment. The K effects suggest II passive distribution of K between the ceIl lind the medium.

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