Influence Of Chemical Treatment Research Articles

Influence of chemical seed and soil treatments onVerticillium-induced yield reduction and tuber defects

Experiments were conducted in 1969 and 1970 to determine the influence of chemical treatments of seed pieces and soil on the development ofVerticillium wilt as measured by tuber yield increases and reduction in severity of tuber defects. The influence of storage onVerticillium-induced tuber defects was evaluated. Seed treatment chemicals tested included zinc ion maneb, maneb, maneb-chloroneb, Polyram, benomyl, and thiabendazole. Soil treatment chemicals included O-Diethyl (O-methyl-sulfinyl) phenyl phosphoro-thioate, disulfoton, phorate, carbofuran, aldicarb, ethyl 4 (methyl- thio)-m-tolyl isopropyl phosphor amidate, benomyl, and thiabendazole. Inoculated seed pieces and artificially infested plot areas were used the first year while the second year natural inoculum from a previous crop was the source of infection. Kennebec and Katahdin cultivars were tested in 1969 and Kennebec alone in 1970. Verticillium-induced yield reductions and tuber defects were more severe in all respects with Kennebec than with Katahdin. With Katahdin the only significant evidence of infection was stem end discoloration. Seed treatments, with the exception of benomyl or thiabendazole, which were erratically phytotoxic, resulted in consistent yield increases and reduction in pink eye severity. In 1969 seed treatment reduced stem end browning in Kennebec. Soil treatment with disulfoton, carbofuran, and aldicarb, both alone and in combination with seed treatments resulted in consistent yield increases with Kennebec. The seed piece and soil treatment combinations tested in 1970 appeared to have an additive effect on yield increase from combination treatments equivalent to the gain from soil treatment alone plus seed treatment alone. The nematicide soil treatment materials did not influence yield. Tuber stem-end browning and pink eye defects in Kennebec did not increase in severity over a five month storage period.

The influence of chemical treatment of glass surfaces on some of its properties

The influence of chemical treatment of glass surfaces on some of its properties

The Influence of Chemical Treatment on the Properties of Wool

The view that the cortex of the wool fiber consists of a resistant fraction, the paracortex, and a less resistant fraction, the orthocortex, which extend in the form of two twisted hemi cylinders from one end of the fiber to the other, is used to explain the mechanism of the alkali- solubility test on acid-damaged wool. The effects of acid damage on several single-fiber prop erties and on the resistance of fabrics to flex abrasion have been measured for correlation with alkali-solubility data. During the initial exposure of the wool to acid damage, alkali solubility is observed to in crease rapidly, corresponding to damage chiefly to the orthocortex; during the later stages, as the damage proceeds into the paracortex, the alkali solubility increases at a much slower rate with time of exposure. The decreases observed in the values for physical properties of the wool with increasing exposure to acid correspond generally with the changes in alkali solubility. Wool treated with formaldehyde, either preceding or following a series of progressive expo sures to acid, exhibits greatly decreased alkali solubility, but fails to show a corresponding im provement in physical properties. It is suggested that the acid acts to degrade the wool fiber by hydrolyzing peptide bonds, and that the formaldehyde treatments decrease alkali solubility by a cross-linking mechanism that does little to improve the physical properties of the wool. A good correlation was found between the flex-abrasion resistance of the variously treated fabrics and the energy to break of the corresponding single fibers. The product of breaking stress and breaking extension, a fiber property related to energy to break, was also found to correlate well with the fabric flex-abrasion resistance.