Leaves sheath

Abaca. The abaca fiber is obtained from the leaves of the banana-like plant (same genus) Musa textilis (banana family, Musaceae). The fiber is also called Manila hemp from the port of its first shipment, although it has no relationship with hemp, a bast fiber. The mature plant has 12—20 stalks growing from its rhizome root system the stalks are 2.6—6.7 m tall and 10—20 cm thick at the base. The stalk has leaf sheaths that expand iato leaves 1—2.5 m long, 10—20 cm wide, and 10 mm thick at the center the fibers are ia the outermost layer. The plant produces a crop after five years, and 2—4 stalks can be harvested about every six months. 

Kouda-Bonafos, M. et al.. Isolation of apigeninidin from leaf sheaths of Sorghum caudatum, J. Chem. EcoL, 20, 2123, 1994. 

Ordinate. Sum of lengths of first and second leaf sheaths of test seedlings. Horizontal lines indicate value of tallest untreated control seedling and responses to 0.01 and 0.1 ng. of gibberellin As... 

Figure 1. Elongation of second leaf sheath of d-1 maize following application of various gibberellins (0.1 pg.) to base of first leaf sheath...

When 10 /J. of hydrangenol and 10 /J. of gibberellin, in appropriate concentrations, were placed separately at the base of the first sheath of d-1 maize, elongation of the second leaf sheath increased with increased concentrations of... 

Figure 4. Mean length of fully expanded second leaf sheath of d-1 mutant maize treated with gibberellin tmd hydrangenol...

The inhibitory properties of the four filtrates and the four eluates were determined by bioassay with the dwarf-1 maize mutant (Table II). Only the first eluate was inhibitory, the next three showing little if any reduction in leaf-sheath length. In contrast, all filtrates were inhibitory. Since the initial. treatment with charcoal and Celite removed only some inhibitory material while subsequent treatments left the remaining inhibitory material in the supernatant, there must be at least two inhibitory materials in the extract, only one of which is adsorbed by charcoal. 

Figure 8. Uptake and translocation of radioactivity in spring barley after treating the upper side of the lower third of the leaf, including the leaf sheath, with [ 4C]triadimefon (macroautoradiographic radioactivity detection). (Reproduced with permission from Ref. 19. Copyright 1978 Pflanzenschutz-Nachrichten Bayer.)...

Rice seedling growth of second leaf sheath 80 ng/ml (23) ... 

Plant waxes are concentrated on leaves and leaf sheaths and on fruit skins, or in some exceptional cases in the seeds of plants. Most vegetable waxes contain predominantly wax esters plus a variety of other lipid materials, which affect the degree of saturation and other properties of the wax derived from different sources. Most use has been made of plant waxes in the cosmetic sector, but there is increasing interest in the use of plant-derived sterols as dietary supplements to reduce cholesterol formation. 

Hemp is made from the bast fibers of Cannabis sativa. This is a larger plant than flax, and produces much coarser fibers. Abaca or Manila hemp is very different from plain hemp. Abaca is made from Musa textilis, commonly called the fiber banana plant. The core fibers of the leaf sheaths of this plant are resistant to salt water, which makes them useful for rope and fabric to be used at sea. It is also used to make handicrafts such as hats and household items. Paper made from abaca has a wide variety of uses, including paper currency (i.e. Japanese yen notes), sausage casings, industrial filters, and tea bags. The finest grade abaca is woven into a cloth called pinukpok. 

Insofar as the allelochemic effects on higher plants are concerned the most dramatic effects were obtained with intact week-old corn plants (Z.ea ma.vs L.) treated with concentrations of carboxyatractyloside at 10", 10 3 and 10- M (100 ul placed inside the uppermost leaf sheath) (35). Responses were visible at 72 hours and consisted of necrotic lesions on leaves at 10 2 M and chlorosis within leaf sheaths at 10 3 and 10 M. One week following treatment there was massive necrosis of the leaves at 10 2 M and a 50% inhibition of growth, while 10 3 m treated plants were inhibited 25%... 

Lig ule.—A membranous appendage at the summit of the leaf-sheath in many grasses and cereals a strap shaped corolla of a Composite. 

Flowers deformed leaves and petals with white flecks. Cause Thrips. Gladiolus thrips are a very destructive common pest. These V25", yellow to black, flying insects feed by rasping petals and leaf surfaces, leaving silvery spots and streaks. They hide under leaf sheaths and inside flowers. Other symptoms are partial bloom, failure to bloom, and shriveling. Thrips wastes may appear as black spots on the undersides of leaves. Infested corms are dark, sticky, and rough. 

Damage Young larvae tunnel within leaves, leaf sheaths, and buds of iris, moving down into crowns and rhizomes as they develop. Soft rots usually follow larval damage. 

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