No abstract

PLANT PHYSIOLOGY rows of orchards than within the orchards, and the formation of precipitates of only slightly soluble salts on the surfaces of leaves in exposed positions. In the present studies this precipitation occurred on the leaves of the oranges sprayed for 1 second every 30 seconds, but there was none on the leaves under continuous irrigation. Continuous sprinkling is known to be practiced without injury in situations where the same water supply intermittently applied causes severe injury. SUMMARY Lemon and orange leaves accumulated more sodium and chloride when irrigated with sprinklers of the intermittent type during the day than they did when similarly irrigated during the night. They accumulated more when intermittently sprinkled than when continuously sprinkled. Intermittent sprinkling permitted evaporation and concentration of the salts in the water films left on the leaves. In advance of the measurements it was thought that little accumulation could be expected from the concentrations of salts in the initial irrigation water, and this proved to be the case.Comparisons were made of absorption by orange seedlings and by rooted lemon cuttings when the plants were inverted and the tops immersed for overnight periods in aerated single-salt solutions. Foliar absorptions by this procedure supported the earlier results and gave a constancy of cation accumulation except when there were heavy accumulations of chloride in association with particular cations.

No abstract

No abstract