Seed, development dispersal

Palmer Amaranth Extracts. The aqueous extracts made from senescent Palmer amaranth leaves and thyrses after seed development and dispersal had little effect on any of the seeds tested (Table II). 

The seed is dispersed from the mother plant endowed with a store of food reserves of protein, carbohydrate and fat in a more concentrated package than occurs anywhere else on the plant. Animals exploit this property when using seeds as an extremely important part of their diet. It is also debatable that civilization began its development when man started to cultivate plants for the food that their seeds provided, especially the cereals—wheat and barley in the Near East and Europe, rice in Asia and maize in the Americas. It need hardly be necessary to remind the reader, moreover, that virtually all of man s exploitation of plants in agriculture depends upon seeds —that they can be stored, transported, multiplied and, most important of all, germinated ... 

The developed method reduced the number of steps required for the synthesis of uniform macroporous beads since the larger uniform seed latices were prepared by the dispersion polymerization relative to those obtained... 

In the natural world, carotenoid oxidation products are important mediators presenting different properties. Volatile carotenoid-derived compounds such as noriso-prenoids are well known for their aroma properties. Examples include the cyclic norisoprenoid P-ionone and the non-cyclic pseudoionone or Neral. Carotenoid oxidation products are also important bioactive mediators for plant development, the best-known example being abscisic acid. Apo-carotenoids act as visual and volatile signals to attract pollination and seed dispersal agents in the same way as carotenoids do, but they are also plant defense factors and signaling molecules for the regulation of plant architecture. 

The flavonoids are a remarkable group of plant metabolites. No other class of secondary product has been credited with so many — or such diverse — key functions in plant growth and development. Many of these tasks are critical for survival, such as attraction of animal vectors for pollination and seed dispersal, stimulation of Rhizobium bacteria for nitrogen fixation. 

While vinyl acetate is normally polymerized in batch or continuous stirred tank reactors, continuous reactors offer the possibility of better heat transfer and more uniform quality. Tubular reactors have been used to produce polystyrene by a mass process (1, 2), and to produce emulsion polymers from styrene and styrene-butadiene (3 -6). The use of mixed emulsifiers to produce mono-disperse latexes has been applied to polyvinyl toluene (5). Dunn and Taylor have proposed that nucleation in seeded vinyl acetate emulsion is prevented by entrapment of oligomeric radicals by the seed particles (6j. Because of the solubility of vinyl acetate in water, Smith -Ewart kinetics (case 2) does not seem to apply, but the kinetic models developed by Ugelstad (7J and Friis (8 ) seem to be more appropriate. 

The dynamic swelling method (DSM) [10] has also been described for the preparation of crosshnked microspheres with free vinyl groups [78]. Therefore, polystyrene seed particles (1.9 pm) prepared by dispersion polymerization are dispersed in ethanol-water (7/3, w/w) containing divinylbenzene (DVB), benzoyl peroxide, and poly(vinyl alcohol) (PVA). The slow drop-wise addition of water to the mixture causes the DVB phase to separate, and it is continuously imbibed by seed particles to produce relatively large swollen particles (4.3 pm), which are then polymerized to afford the respective PS-PDVB composite particles with free vinyl groups. DSM has recently been developed in order to prepare hohow microspheres and various oddly-shaped polymer particles, including a rugby ball, red blood cells, or snowman structures [79-83]. 

Fruit Development and Seed Dispersal Edited by Lars 0stergaard... 

Inoculation. This is the first step in the development of any infectious disease. Inoculation occurs when the disease-causing factor (the inoculum) comes into contact with the plant. There are many ways by which pathogens can spread to your plants, including wind, rain, insect feeding, contaminated tools, and in infected seeds or transplants. R>r more information on how pathogens disperse, see Reproduction, dissemination, and oserwin-... 

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