Waxy Bloom Research Articles

Leaf Wax and Transpiration in Brassica oleracea L.1

Abstract Water loss in relation to the wax associated with the surface of leaves of Brassica oleracea was investigated. Varieties of Brussels sprouts, broccoli, cauliflower and collards were found to possess highly significant differences in regard to stomatal transpiration, cuticular transpiration and quantity of wax per unit area of leaf surface. Rubbing away the waxy bloom increased the cuticular transpiration rate. There was little correlation between the quantity of wax and the water loss per unit area of leaf surface either during the daytime or nighttime experiments. It appears inadvisable to attempt to breed for drought resistance in Brassica oleracea by selecting for the presence of a heavy waxy bloom or high levels of wax per unit area of leaf surface.

The Lowbush blueberry industry in Eastern Canada

A great number of morphologically distinctive blueberry populations, representing many species and suggesting extensive hybridization (16), occur throughout North America. The east Canadian population consists essentially of four species (25, 2, 3). Oddly enough, although these differ in form as described below, the fruits are quite similar in size, flavor and extent of waxy bloom. They have been harvested from the wild for generations and, together, with venison, were a major component of the Indian's pemmican. Vaccinium corymbosum L., the highbusb blueberry, occurs in swamps and lake-marginal regions throughout southwestern NovaScotia. The native population is too limited to be of commercial importance, but cultivars selected in the United States have been propagated and planted in increasing numbers in this area. A diminutive species, Vaccinium boreale Hall & Aalders, occurs in exposed northern regions of Cape Breton Island and in Newfoundland (25). It is not economically important. The two species of lowbush blueberries that constitute the bulk of the native crop occur together in most blueberry fields. The velvet-leaf blueberry, Vaccin.ium myrtilloides Michx., predominates in fields newly developed from woodlots. The common lowbush blueberry, Vaccinium angustifolium Ait., dominates in fields developed from abandoned hay fields (24), and the produce from this constitutes more than three-quarters of all lowbush blueberry production. For many years, attempts have been made to cultivate blueberries. This has resulted,

GLAUKOMA AND GLAUCOMA.

Glaukoma is an ancient Greek noun meaning glaze, such as the silveriness of the sea, the waxy bloom on a plum or a grape, or the dull sheen or glint of an eye that has lost its brightness. glaze of death over his eyes. Glaukoma is no definite morbid entity but merely the off-color lack-luster appearance of a blind eye. Least of all does it mean opacity of the crystalline lens, cataract, as defined in Liddell and Scott's Greek-English Lexicon—a definition palpably wrong, for the ancient Greeks had no concept whatever of cataract as such. Nor can glaukoma mean glaucoma, which only in very modern times has been recognized as an entity. Glaukoma to the ancient Greeks was simply glaze, a visible objective manifestation of partial or complete blindness. All dictionary definitions of ancient medical words are suspect, tending to be vitiated by the almost unavoidable fallacy of interpreting ancient medical words in terms of modern knowledge. The ancients knew nothing of pathology as we know it, and their whole concept of ocular pathology hardly extended beyond the concept of blindness, with very little differentiation. In general ancient medical terms have

POPULATION DENSITY AS A CRITERION FOR EVALUATING VARIETAL RESISTANCE OF CASTOR (Ricinus communis LINN.) TO JASSID INFESTATION

Investigations were taken up to assess the degree of relationship of the jassid population with the varied types of waxy bloom coatings and stem colours of castor. Jassid population counts were recorded on a total of seventy- six varieties of castor maintained at the Agricultural Research Institute, Coimbatore during 1961-62 monsoon season.

Studies of the Fine Structure of the Wax Layer of Sultana Grapes

The surface waxy bloom of sultana grapes has been studied using the carbon. replica technique in combination with electron microscopy. This layer consists of a series of overlapping wax platelets, each of which is about 0�1 f' wide. The air spaces between the wax platelets become filled with liquid when sultana berries are dipped in commercial emulsions known to accelerate their drying rate. Washing in distilled water removes this layer of dipping emulsion from the surface. The appearance of dipped and washed grapes is similar to that of untreated grapes.

Gene Interaction in Ricinus Communis, L.1

SynopsisThe major phenotypes in the wide range of plant and capsule colors in Ricinus communis, L. were accounted for by the action and interaction of at least three major genes. One partially dominant gene controlled the production of spines on capsules. The interaction of three genes was demonstrated in the inheritance of waxy bloom.

The occurrence and inheritance of waxy bloom on sorghum

All sorghum varieties develop a waxy bloom. When heavy this bloom is present on the leaf-sheath, leaf-blade, internode, panicle branch and glume. It is best seen at flowering time. When sparse, the bloom is easily seen at the top of the leaf-sheath, top of the internode, and the base of the under-surface of the leaf. Some groups of sorghum show the bloom in heaviness and others in sparseness. The heavy bloomed condition (H) is a simple dominant to the sparse bloomed condition (h). The factor (H) is independent in inheritance to the leaf-sheath colour factors P and Q, leaf margin disposition factor Mu, grain surface structure factor Z, and the brown grain factors B1 and B2.

The Larval Wax Glands of the Dogwood Sawfly (Macremphytus Varianus Norton).*

Waxy secretions have been observed on the larvae of various species of sawflies (Tenthredinidae) especially in the subfamilies Diprioninae, Emphytinae, Selandriinae, Tenthredininae and Nematinae. In some cases the secretion was scanty, being evident as a waxy bloom on the surface of the cuticula. In others it was considerable, forming flocculent masses which concealed the entire body of the larva. Packard (1898)[†][1] described and figured the larva of a Selandria whose body was nearly concealed by long thread-like masses of wax. So far as could be ascertained no description of the wax glands of any species of sawfly has appeared in entomological literature. Consequently a discussion of the structure of these glands in the larva of Macremphytus varianus Norton will not be out of place at this time. [1]: #fn-2