Potatoes with orange flesh were found in cultivated diploid (2n = 24) potato populations derived from Solanum stenotomum Juz. et Buk. and S.phureja Juz. et Buk. The orange flesh trait was found to be controlled by an allele at the Y- locus designated Or. Or is dominant over Y and y, which control yellow and white flesh, respectively. In a comparison of white and orange flesh segregants from crosses, the orange was associated with large amounts of zeaxanthin, a xanthophyll previously not reported as a constituent of potato flesh carotenoids. The combined total of lutein and zeaxanthin was four times higher than the highest carotenoid composition previously reported for potato, this is about one-sixth the total carotenoid content of carrot with standard carotenoid levels, although lutein and zeaxanthin do not possess provitamin A activity.

The polymeric material (suberin) of the wound periderm of potato tuber slices was analyzed after depolymerization with LiAlH4 in tetrahydrofuran or BF3 in methanol with the use of thin layer chromatography, chemical modification, and combined gas-liquid chromatography and mass spectrometry.Fatty acids (C10 to C26), fatty alcohols (C16 to C26), octadec-9-ene-1, 18-dioic acid, and 18-hydroxy-octadec-9-enoic acid were identified to be the major components. Based on the structural information that the two bifunctional C1s molecules constituted a major portion of suberin, a gas chromatographic method of measuring suberization was developed. This method consisted of hydrogenolysis of powdered tissue followed by thin layer chromatography and gas chromatographic measurement of octadecene-I , 18-diol as the trimethylsilyl ether. With this assay it was shown that the development of resistance to water loss by the tissue slices was directly proportional to the quantity of the bifunctional C1s molecules, thus providing evidence that a function of suberin is prevention of water loss.Suberization is an important process because suberin plays a key role in preventing weight loss and decay, two of the major problems in the potato industry (4, 12). Suberization of potato tuber tissue has been studied by many investigators (7,8,11 have been available. In this paper we report the results of structural studies on the polymeric material of wound periderm of potato tuber tissue. Structural analysis by combined gas-liquid chromatography and mass spectrometry showed that the aliphatic constituents of the suberin formed on the wound surface are very similar to those found in the natural skin of potato tuber. A gas chromatographic method for quantitating suber-

The structure and composition of the aliphatic monomers of the polymeric material deposited during wound-healing of tomato fruit, bean pods, and Jade leaves were examined. After removing the cuticlecontaining layer of tissue, the wounds were healed for 14 days and the resulting surface layer was excised, lyophilized, solvent-extracted, and depolymerized by hydrogenolysis with LiAIH4 or transesterified with BF3 in methanol. The products obtained by the chemical depolymerization were subjected to thin layer chromatography and combined gas chromatography and mass spectrometry. The major aliphatic components isolated from the hydrogenolysate of the wound polymer produced by tomato fruit were hexadecane-1,16-diol and octadec-9-ene-1,18-diol, which were shown to be derived from a 1:1 mixture of w-hydroxy and dicarboxylic acids of the appropriate chain length by LiAIH4 reduction.Also identified in the wound polymer were long chain (>C20) fatty acids and alcohols. This monomer composition is typical of suberin polymers and is in sharp contrast with that of the cutin of tomato fruit which contains dihydroxy C16 add as the major aliphatic component. The hydrogenolysis of the wound material from bean pods gave octadecene-1,18-diol as the major aliphatic component, and smaller amounts of hexadecane-1,16-diol and long chain alcohols. Similar treatment of the normal cuticular tissue of these pods gave hexadecane triol, as well as C16 and C18 alcohols. Hydrogenolysis of wound material from the Jade leaves gave octadecene-1,18-diol, C16 and C22 diols, as well as alcohols from C16 to C26, whereas similar treatment of the cutin-containing tissue from these leaves gave C16 triol as the major aliphatic component. Thus, the major aliphatic monomers of the polymeric material deposited during the wound-healing of bean pods and Jade leaves are very similar to those of suberin, although the natural protective polymer of these tissues is cutin. From these results, it is concluded that suberization is a fundamental process involved in wound-healing in plants, irrespective of the chemical nature of the natural protective polymer of the tissue.In recent years, the composition of the monomers of cutin and suberin, the lipid polymers which cover plants, has been studied with modern analytical techniques. The major components of cutin are dihydroxy C16 fatty acids, 18-hydroxy-9,10-epoxy C18 fatty acids, and trihydroxy C18 fatty acids. Also found are smaller amounts of w-hydroxy C16 and C18 fatty acids. The major aliphatic components of suberin are w-hydroxy fatty acids and dicarboxylic acids from C16 to C28 and fatty acids and alcohols in which aliphatic chains longer than C20 often predominate (4,6,7,10,13,17). The composition of the aliphatic monomers of the '

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