Introduction
Acacia senegal (L.) Willd. Leguminous tree, subfamily Mimosaceae is an important multipurpose tree of desert and commonly found in arid of Rajasthan, Gujarat and undisturbed area of Punjab and Haryana. Locally it is known as kumata / khair / kheri. In Gujarat it is known as kagar; goraduja baval. In Hindi it is also known as khor, humath. In other countries, it is known as geelhoak (Africans); alloba (Arabic); gum arbic, Sudan gum Arabic, gum acacia, three-throned acacia (English); acacia du senegal (French).
Acacia is abundant in savannas and arid regions of India, Australia, Africa and America. Many species of Acacias are exceedingly robust and grow under the most severe conditions. Fabaceae or Leguminosae is a large and economically important family of flowering plant. It is commonly known as legume family, pea family, bean family and pulse family. Fabaceae is third largest family of flowering plants behind Orchidaceae and Asteraceae, with 730 genera and over 19400 species according to Royal Botanical Gardens and Acacia with 900 species.
Tree grows up to 8 m in height, with umbrella-shaped or flat or rounded crown (Maundu et al., 1999). It is based chiefly on characteristics of the seed and seedlings, absence of stipular spines (but prickles present) and pollen characteristic. It is very branched with many upright twigs (Von Maydell, J.H. 1990). Selection of the best seed sources of A. senegal for given region is necessary for maximum productivity in plantation forestry and agro forestry systems (Subramanium et al., 1992). Tree breeder wants to explore the naturally occurring variability which permits tree breeder to make rapid genetic advance.
All forest species have large heterozygocity and they also show conside...
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...e species. Accordingly Chikamai and Banks (1993) reported that in A. senegal, the chemical and molecular structure of gum arabic differs according to botanical origin of the populations. As a result the functional properties, uses and commercial value are dependent on origin (Chikamai and Odera, 2002).
Recently scientists have shown an increasing interest on the reproductive biology of tropical trees such as Leucaena (Brewbaker, 1983), the genus Acacia (Tybirk, 1989; Tybirk, 1992; Buitlaar, 1993; Diallo, 1997), Saba senegalensis (Traoré, unpubished), and the monospecific genus Faidherbia albida (Gassama-Dia et al, 2003). Regarding B. aegyptica, some preliminary studies on seed pregermination treatment and vegetative propagation were mentioned by El Nour et al. (1991). This paper presents results on the flowering, pollination and reproductive capacity in A. senegal.
Esters are defined as molecules consisting of a carbonyl group which is adjacent to an ether linkage. They are polar molecules which are less polar than alcohols but more so than ethers, due to their degree of hydrogen bonding ability. Most often derived from reacting an alcohol with a carboxylic acid, esters are a unique, ubiquitous class of compounds with many useful applications in both natural and industrial processes 1. For example, within mammals, esters are used in triglycerides and other lipids as they are the main functional group attacking fatty acids to the glycerol chain 2. A unique property of esters is their tendency to give off distinct aromas such as the scent of apples (Ethyl caprylate) and bananas (Isoamyl acetate). This is of a unique importance especially in industries that utilize flavors and aromas such as the tobacco, candy and alcohol industry. Consistent research is conducted in order to enhance and increase the effectiveness of esters in these products 3.
In the northern region of Africa there is the Sahara desert. This is why there are very few natural fuel wood resources located there. It is mostly arid land with few oases. Also in the northern region by the Mediterranean Ocean there is satisfactory resources since it is located near the ocean, which means there is enough water to support tree growth. Right below the Sahara desert there is a big area of fuel wood scarcity. This area is a dry region. There is very little rainfall, which results in the scarcity of wood for fuel. Some parts of Africa, which has very, little fuel wood is led up because of too much deforestation. Many people already used up all these fuel wood resources through out these years and now there is not enough for people to use.
Holt, Ben F. and Gar W. Rothwell. 1997. Is Ginkgo biloba really an oviparous plant? American Journal of Botany 84(6): 870-873.
Orchids are the most common plant in the Amazon. There about 25,000 to 30,000 species of Orchids. Orchids can live in every continent except antarctica and the arctic because its too cold for the Orchids in the antarctic and the arctic. Some Orchids grow bigger than a dinner plate that you eat off of. Orchids scientific name is Orchidaceae. Dactylorhiza fuchsii are the most common species of all Orchids. There are no known poisonous Orchids but since there are so many species that is virtually impossible to test all of them. Since Orchids are very common i don’t know...
Fruiting heads often remain on trees over winter. Fair seed crops occur every year and bumper crops about every 3 years. The staminate and pistillate of Sweetgum is monoeciouse. The small, greenish flowers bloom from march to early May, depending on latitude and weather conditions. Both the staminate and pistillate flowers occur in heads. The staminate inflorescences are racemes; the solitary pistillate flowers are globose heads that that form the multiple head, 2.5 to 3.8cm in diameter, of small, two-celled capsule. The lustrous green color of the fruiting heads fades to yellow as maturity is reached in September to November. The beaklike capsules open at this time, and the small winged seeds, one or two per capsule, are then readily disseminated by wind. However, the seed balls can be safely collected for seed examination several weeks before ball discoloration occurs without harming the seed. Empty flowers are quit sensitive to cold and often damaged by frost.
...le would be more than that of American beech because sugar maple produce more seeds than American beech. Furthermore, we study whether the two species co-exist via reciprocal replacement, habitat preference or merely by chance. We believe that habitat preference may be the mechanism of coexistence here and therefore we hypothesize that there will be more American beech tree neighbors as they may represent the most biomass as per our third hypothesis. Thereafter, root sprouting is effective in American beech to give them a greater horizontal growth than sugar maple. Hence, we hypothesize that sugar maple canopies will be less asymmetrical than American beech. Finally, because a nearby canopy may restrict a tree canopy growth in the same direction, we hypothesize that a tree will grow its respective canopy away from its neighboring canopy to receive maximum sunlight.
Savannas are part of the Grassland biome, and are generally found in regions dominated by the "Wet-Dry Climate." Tropical Savannas encompass almost one half of the entire continent of Africa as well as many parts of Australia, India, Mexico, and South America. The Tropical Savannas in Australia take up over one-third of the country, and provide natural resources that contribute much of the money that supports the national economy.
Brazil nuts are harvested at plantations and in the wild. Plantations are being developed in various parts of the Amazon. Fazenda Aruana is the owner of a 12,000 hectare former cattle ranch, partially converted to a Brazil Nut plantation in 1980. By January of 1990, 318,660 Brazil nut trees were planted on 3341 hectares of land. Fazenda's original intent was to plant Brazil Nut trees in a 20 by 20 meter grids and allow cattle grazing between the trees. The trees in the Aruana plantation are the result of grafting high yield clones from the region of Abufari Amazonas were Brazil nuts are know for their large fruits and seeds. As a result of fertilization from the same clones, the fruit production among clones has been low(2). Another danger in using so few clones is the ability to resist attack of disease and insects.
Every day the hot, humid air rises off the ground and collides with cooler air above and turns into rain. In the afternoons on the summer savanna the rains pour down for hours. There are a few distinct sorts of savannas around the globe. The savannas we are most acquainted with are the East African savannas secured with acacia trees. The Serengeti Fields of Tanzania are probably the most understood. Plants of the savannas are very specific to develop in this environment of long stretches of dry season. They have long tap roots that can achieve the profound water table, thick bark to oppose yearly flames, trunks that can store water, and leaves that drop of amid the winter to save water. The grasses have adjustments that demoralize creatures from eating on them; a few grasses are too sharp or intense tasting for a few creatures, yet not others, to eat. The side advantage of this is each types of creature has something to eat.
Lying on Ethiopia’s southern border is Kenya. On the south western border sits South Sudan and Sudan covers the north western border (Ofcansky and Berry). Much of Ethiopia is covered by highlands, plateaus and mountains and with this country’s climate is categorized as primarily H with some subcategories of B in the Köppen system (Attoh). The Western Highlands and Eastern Highlands that consume most of Ethiopia are dissected by the Eastern Rift Valley that slices through from the northeast to the southwest. The highlands here are classified as H climates, which means that they experience temperate climates and dry winters.
(Minifie B.w, 1989) The cocoa tree (Theobroma cacao) is a surprising tree, which is growed in certain constrained ranges and atmosphere conditions; it is a local of thick tropical timberlands of the Amazon where it develops in semi shade, and high modesty and it is accepted to have spread regularly westwards, and northwards to Guyana and Mexico then later headed to the Caribbean islands. (Morganelli A, 2006) the cocoa tree first develop in rainforests of south and focal America, Its first cultivator s from harvests to trees where the aged Mesoamerican and most cocoa trees are developed in spots close to the equator where the climate is constantly hot and wet. (Backett S.t, 2008) To be called ''...
Furthermore, as the Liliaceae family is primarily ornamental they have a significant commercial value i...
It also has many woody shrubs such as Corylus avellana (Hazel), Euonymus europaeus (Spindle) and Ilex aquifolium (Holly). All these species are dependent on the amount of sunlight that they obtain. Woodlands mainly consists of a Canopy Layer: large trees greater than 5m in height, an Understory Layer: younger species of the dominant trees, Shrub Layer: small, woody plants, Herb Layer: flowering plants, fungi and grasses and the Moss Layer: variety of mosses and
The Maasai live throughout north central Tanzania and southern Kenya. Kenya Maasailand is presently located near the coast in the Narok and Kajiado districts. The territory in 1981 measured approximately 39,476 square kilometers. Details on the environment in this area are necessary in order to understand the Maasai people who depend upon it for their survival. The region is typical of arid and semi-arid lands. The Maasailand area has an extremely low amount of surface water, and shallow alkaline soils which proves to be a difficult problem for their cattle-raising practices, and the main reason why they have adapted pastoralism rather than agriculture. The amount of rainfall varies greatly (usually less than 500 mm a year) , with occasional violent storms erupting. The location of the rain may be very specific, effecting a very small area without touching a nearby location. The amount of rainfall fluctuates every year and droughts are frequent. The Maasai have adapted to their living co...
Fossil records are unable to provide information of on the center of origins of the cacao tree. The cacao tree is in the Sterculiaceae family. The first growers of the cacao pods were probably the people who entered the lowland rain forests of the Amazon Basin between 10,000 and 200 B.P. The full name of the cacao tree is Theobroma cacao. Most of the information of the cacao have been derived from the cultivated crop. The life and reproduction life cycle of Theobroma cacao is identical to a tropical rain forest tree species. Cacao grows optimally in minimal moisture and shade. Cacao is dispersed in small, medium and large areas. This is probably the result of animal dropping the seeds after eating the tasty inside of the pods. Cacao pods are very diverse in morphology. These morphological difference suggests genetic differentiation.