Flower pollination

Knuth, P. (1906). Handbook of Flower Pollination, vol. 1. [Based upon Hermann Miiller s work The Fertilization of Flowers by Insects.] Oxford Clarendon Press. 

Recent studies by Aaron Reisfield (Reisfield 1993) demonstrate that Salvia divinorum is not completely self-sterile, as had been assumed the plant can produce viable seeds, though very infrequently. Nor did Reisfield find any significant difference in the production of viable seeds from flowers pollinated from the same clone and those pollinated by plants collected from different localities. It is of course possible that there is little genetic difference between any specimens of S. divinorum, even those that today grow in widely separated areas in Oaxaca. 

The greenhouse and growth-chamber experiments indicated that S. divinorum is an obligate short-day plant. Plant height is a minor factor in flower development, as several (growth chamber) specimens were less than 0.5 m tall when they flowered. Pollination experiments showed that the mint is probably self-sterile, but it remains to be demonstrated that S. divinorum will set viable seed. 

Flowering, pollination, nectar standing crop, and nectaries of Euterpe precatoria, an Amazonian rain forest palm. Plant Systematics and Evolution, 206, 71-97. 

The most important considerations in marketing and estabUshing a crop from a new source are constancy of supply and quahty. Eor some spices, it is difficult to reduce labor costs, as some crops demand individual manual treatment even if grown on dedicated plantations. Only the individual stigmas of the saffron flower must be picked cinnamon bark must be cut, peeled, and roUed in strips mature unopened clove buds must be picked by hand and orchid blossoms must be hand pollinated to produce the vanilla bean. 

Vanilla. Vanilla is the dried, cured, fuU-sized, but not fully ripe fmit pods (beans) of Vanillaplanifolia And. and V. tahitensis J. W. Moore (Orchidaceae). The vine is native to the tropical rain forests of southern Mexico, Central America, the West Indies, and northern South America. Plantings were started in Madagascar, Reunion, Java, Mauritius, and Zanzibar in 1840. The Madagascar-type bean is stUl the most important, but Indonesia produces more than Malagasy. The stmcture of the flower prevents self-pollination and therefore, where insects are not prevalent, hand pollination is necessary. 

The function of the essential oil in the plant is not fully understood. Microscopic examination of plant parts that contain the oil sacs readily shows their presence. The odors of flowers are said to act as attractants for insects involved in pollination and thus may aid in preservation and natural selection. Essential oils are almost always bacteriostats and often bacteriocides. Many components of essential oils are chemically active and thus could participate readily in metaboHc reactions. They are sources of plant metaboHc energy, although some chemists have referred to them as waste products of plant metaboHsm. Exudates, which contain essential oils, eg, balsams and resins, act as protective seals against disease or parasites, prevent loss of sap, and are formed readily when the tree tmnks are damaged. 

The bright colors of flowers and the varied hues of autumn leaves have always been a cause for delight, but it was nor until the twentieth century that chemists understood how these colors arise from the presence of organic compounds with common structural features. They discovered how small differences in the structures of the molecules of these compounds can enhance photosynthesis, produce important vitamins, and attract pollinating bees. They now know how the shapes of molecules and the orbitals occupied by their electrons explain the properties of these compounds and even the processes taking place in our eyes that allow us to see them. 

Cenozoic Tertiary 66 Myr Climate Cools. Continents nearing modern positions. Drying trend in middle of period. Radiation of birds, mammals, flowering plants, pollinating insects... 

Elder stems with their pith removed make a nesting site for solitary bees. This is helpful near fields of alfalfa, where the presence of bees aids plant pollination. Elder s summer flowers provide an important source of nectar for many insects. Swallow-tailed... 

The flowers are small, about 1/5 of an inch long with five lobed corollas with five stamens and short filaments. The flowers are fragrant and form a flat-topped cluster (known as a corymbose cyme) with stalks of different lengths all growing to the same level. They bloom from the center outward. The flowers are often pollinated by flies and other insects. The purplish black berries, which ripen in September in the Northern Hemisphere, contain ovate greenish brown seeds. The berries are actually black, but have a powdery blush on them which makes them appear blue. There are often three seeds in each berry. Red berries, which should not be eaten, have too high a saponin content which even keeps animals from consuming them. Plants can usually reproduce by the time they are three to five years old. 

The two types of wood differ, however, in their nature and structure. The main structural characteristic of the hardwoods (which are botanically known as angiosperms, plants that flower to pollinate for seed reproduction) is that in their trunks or branches, the volume of wood taken up by dead cells, varies greatly, although it makes up an average of about 50% of the total volume. In softwoods (from the botanical group gymnosperms, which do not have flowers but use cones for seed reproduction) the dead cells are much more elongated and fibrous than in hardwoods, and the volume taken up by dead cells may represent over 90% of the total volume of the wood. 

Flowers of some orchids mimic both the appearance and sex pheromone of virgin females of certain species of bees or wasps. This sexual deception results in pollination by male hymenoptera that would not normally visit flowers. Japanese honey bee drones (Apis cerana japonica) cluster on the oriental orchid (Cymbidiumpumilum) while on their mating flights [ 134]. By comparing volatile profiles of orchids and the female hymenoptera they mimic, or by GC-EAD and GC-MS analysis of orchid volatiles, several compounds have been identified that may mediate this attraction for the solitary bee Andrena nigroaenea [135, 136] and the scoliid wasp Campsoscolia ciliata [135]. 

Insects are considered to be another potential vector for faecal material to produce in production areas (Geldreich et al., 1964). Pollinating insects might inoculate flowers with pathogens opening the pathway for fruits to internalize pathogens and eliminating their accessibility to surface decontamination (De Roever, 1999). 

Anthocyanins are colored flavonoids that attract animals when a flower is ready for pollination or a fruit is ready to eat. They are glycosides (i.e., the molecule contains a sugar) that range in color from red, pink, and purple to blue depending on the number and placement of substitutes on the B ring (see Fig. 3.7), the presence of acid residues, and the pH of the cell vacuole where they are stored. Without the sugar these molecules are called anthocyanidins. The color of some pigments results from a complex of different anthocyanin and flavone molecules with metal ions. 

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