Bud scales

Fungal disease similar to apple scab (q.v.) but infection also often occurs on bud scales. Scab is worse in cool, wet periods in spring and early summer. 

NATURE OF DAMAGE. In winter poor closure of the bud scales, the buds are often wrinkled and die off infected shoots are whitish (powdery coating). 

PRIMARY INFECTIONS. The mildew fungus overwinters as mycelium in the buds. If there is very severe frost in winter, some of the infected buds may die off, as the bud scales are not completely closed. In the closed buds the mycelium produces conidia, which infect the young leaves, blossoms and fruit when the buds open. Infection may occur at the greenbud or redbud stage if weather conditions are favourable. The first symptoms of primary infections can then be seen on the leaves and petals at flowering. Apart from the climatic conditions, for mildew infection to develop the tree must also have susceptible tissue (very young leaves) available. The leaves acquire age resistance to mildew at an even earlier stage than they do to scab. 

SECONDARY INFECTIONS. Infected leaves produce conidia which can in turn infect young, susceptible leaves. The fungus develops first on the underside of the leaf In autumn the fungus grows down the stem and penetrates into the buds which are forming, before the bud scales become corky. This is also a particularly critical point in mildew infections, as both lateral and terminal buds can be infected. 

The deutogynes (winter females) overwinter under bud scales, in cracks in the bark near bud scales, or under moss and algae on the bark. As soon as the buds open, the overwintering mites migrate to the rosette... 

LIFE CYCLE. They overwinter as semi-adult caterpillars in crevices in the bark or beneath bud scales. They emerge at budburst and feed on the rosette leaves and blossom trusses, which they often web together. A dried leaf is usually incorporated in this web. The caterpillar of Spilonota ocellana develops rather more slowly than that of Hedya nubiferana and occasionally feeds on the young fruit beneath a leaf that... 

NATURE OF DAMAGE. The leaf and blossom buds do not open in the spring. These buds are still closed while the other buds are already coming into flower. The bud scales are not completely closed but rather lacerated. 

Prepare plant extract. Grind material (acorn parts, bud scales, bark, or leaves) into fine powder. Extract 100 mg material (ground acorn tips or bases, or powdered bud scales) in 0.5-ml MeOH/HjO (50 50) [or a 70% acetone-MeOH mixture] for 1-3 h at room temperature. Pipette off supernatant. 

Buds are short young shoots with or without rudimentary leaves (bud scales) compactly arranged upon them. 

Free lateral stipules are seen in Leguminosce, Rosaceoe, Beeches, etc. They are free on either side of the petiole and supplied by vascular tissue from the petiolar bundle mass. In appearance and duration they may be either green, foliaceous and persistent or membranous to leathery, scale-like and caducous. Caducous scaly stipules only function as bud scales through the winter and fall in spring as the buds expand. 

Leaves alternate, simple, entire, stipulate stipules rarely green, persistent, usually functioning as winter bud-scales and falling in spring. 

Scales are normally rather thin, yellowish to brown membranous leaf structures, very variable in size and form. On woody stems they are present as bud scales which protect the bud they are also found on rhizomes such as common couch. 

RENiFORM. Kidney-shaped RESINOUS. Containing or producing resin, said of bud scales when coated with a sticky exudate of resin (as in Aesculus spp.)... 

Fig. 17 Correlation between 10 year s growth of shoots (L 10) and their basal diameter (D) at the 10-year-old bud scale scar (vc = vitality class after ROLOFF 1985)... 

Fig. 1. Scanning electron micrograph showiag ceUs of S. cerevisiae. Bud scars are visible at the ends of ceUs. Scale bar is 5 p.m.

Quaking aspen Populus tremuloides Scales of flower buds Ruffed grouse Bonasa sp. Coniferyl benzoate Jakubas etal., 1989... 

In onion bulbs, if some growth of inner buds takes place already before irradiation, the treatment causes the death and discoloration of the inner buds. The area of this discoloration depends on the size of the inner buds at the time of irradiation. Pilot scale studies in Hungary have shown that the yield of unirradiated onions prepared for drying after storage was 29% of the original compared to 55% in irradiated onions. The dehydrated onions prepared from irradiated bulbs had better quality than did the controls. No discoloration of the inner buds occurred in bulbs of cultivar Alsogodi irradiated at 0.05 kGy and stored up to 8 months [25]. Similar results were reported earlier from Egypt [26] whereas some studies in the United States have indicated that inner-bud discoloration of irradiated onions may lower the quality of dehydrated onion slices or powder prepared from them [27]. 

Corm Short, bulblike fleshy stems, invested with a few thin membranes or scale leaves, and bearing buds at the summit. 

Tuber A short fleshy, usually underground, stem or shoot, bearing minute scale-like leaves with buds in their axils. 

SCALE Leaf-like structures borne on moss gametophytes and flat structures borne on liverworts any thin membranous, chaffy, or woody bract one of the cataphyllary leaves serving in many seed plants to cover a bud before expansion. 

Eastern North America is now experiencing perhaps the most extensive epidemic yet recorded susceptible stands have been defoliated for several years throughout more than 40 million hectares. This has prompted the large scale use of insecticides over millions of hectares annually in an attempt to protect the trees and to keep them alive until they can be harvested. Research is being conducted in Canada and the U.S. to find alternative strategies and techniques for controlling the bud worm. 

Oakmoss is a sort of lichen that grows on oak trees, and its extract has an important role in fragrance design.101 Cinnamon oil is obtained from the bark of the cinnamon tree, although small-scale production of leaf oil is also known. Cassia oil is obtained from the bark, small branches, and leaves of the Cassia tree. Clove oil is prepared by steam distillation of clove buds, while clove leaf oil is made from leaves (Table 11). 

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