Article

THE EFFECT OF PRE‐EMERGENT TREATMENT OF PEAS WITH TRICHLORACETIC ACID ON THE SUB‐MICROSCOPIC STRUCTURE OF THE LEAF SURFACE

Department of Botany, Oxford
New Phytologist (Impact Factor: 6.74). 03/1959; 58(1):1 - 4. DOI: 10.1111/j.1469-8137.1959.tb05328.x

ABSTRACT Peas were sown in sand, which was treated with varying concentrations of trichloracetic acid. The behaviour of water droplets on the leaves of peas was observed, and it was found that the angle made by the droplet on the surface falls with increasing concentration of T.C.A. No changes in leaf structure, which could account for these changes in behaviour, were revealed by ordinary light microscopy. Investigation of the sub-microscopic anatomy of the surface by the carbon replica technique under the electron microscope did reveal significant differences in the leaf surfaces. A reduction in the number and a change in form of the minute wax structures occurs with an increased concentration of T.C.A. in the soil. These changes correlate well with an increase in the wettability of the leaf surface as determined by the contact angle of water droplets.

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