The work of the plant-breeder has made available a great number of varieties of agricultural plants, many of them specially adapted to different climates, soils, markets and conditions of disease and insect infestation. It is obviously important, once the character of a variety has been fixed by the breeder, that the seed be kept pure, that is (from a practical standpoint) free from detrimental admixture and reasonably uniform in the important varietal characteristics. [...]

Off-flavour development in raw or underblanched vegetables occurring as a result of an imbalance in the enzyme reactions was recognized early in the development of the frozen vegetable industry by Joslyn (1930), Tressler (1932) and Diehl and Berry (1933). Since then, numerous investigations have been carried out on various aspects of this problem but the reactions involved are still largely unknown. The investigators seem to agree that off-flavours are due to an enzymatic process because they do not develop in properly blanched vegetables.

The potato is, undoubtedly, a native of South America where it was in cultivation by the natives long before the discovery of America. It originated in the central Andean region of South America, but there is controversy concerning the original home of the plant as to whether it was in Chile or in Peru and Bolivia. There is also some doubt as to whether the potato was introduced into North America from Europe, or brought directly from South America by Spanish explorers.

Studies on a new method, employing a portable battery-powered Bouyoucos bridge and a needle electrode clamp cell, to estimate the vigour of apple rootstocks from the electrical resistances of living twigs, were carried out in 1959 and 1960. The electrical resistances of past year's twigs of 14 rootstook varieties were arranged in the following order: Kerr, K.XVI, O-524, M. Robusta No.5, M.XIII, M.XII, M.I, M.3430, M.II, M.VII, M.3428, K.3436, M.IX and M.3426. There were significant differences between major vigour groups.

The strawberry is a native of North America. The cultivated berry, as it is known today, is a relatively recent product of plant breeding. The cultivated strawberry is derived from two species. They are Fragaria virginiana, the wild meadow strawberry of eastern North America, and Fragaria chiloensis, the beach strawberry, which is found along the Pacific coast. The first improvement occurred among the Indians of Chile before Columbus landed at San Salvador. By selection from Fragaria chiloensis, they obtained plants which bore fruit of exceptional size and quality.

Thesis--Wisconsin. / Includes bibliographical references (leaves 224-243).

<p> <i>Macrophomina phaseolina</i> is a generalist ascomycetic fungal pathogen, capable of infecting over 500 genera of plants and limiting yield in crops grown in Mississippi. Recent documentation of <i>M. phaseolina </i> on <i>Impatiens</i> &times; <i>hybrida,</i> a newfound host, has merited multiple experiments to quantify the exact nature of this relationship. Despite <i>M. phaseolina</i> being a soil-borne pathogen, disease symptoms were only reported in aboveground tissue. Mode of infection experiments revealed both above and belowground tissues are susceptible to infection. <i>In vitro</i> experiments identified the optimal temperature for the growth of <i>M. phaseolina</i> to be 26&deg;C, where more than 10x the accumulated biomass resulted compared to samples grown at 37&deg;C. <i>Impatiens</i> &times; <i>hybrida</i> hosts were particularly prone to infection at temperatures above 27&deg;C. <i> In vitro</i> fungicide assays revealed Banrot and T-Bird to be suitable chemical control agents for limiting <i>M. phaseolina</i> growth. </p><p>

[No abstract available] / Land and Food Systems, Faculty of / Graduate

No description available.

No description available.