Plant breeding is defined as identifying and selecting desirable traits in plants and combining this into one individual plant. Since 1900, Mendel’s laws of genetics provided the scientific basis for plant breeding. Selection is the most ancient and basic procedure in plant breeding. Selection procedures used in plant breeding have …

Plant improvement must have been started with the primitive man changing his mode of life from a nomad to an agriculturist. To have a crop in the next season, he had obtained seeds from the first crop. For this, unconsciously the process of selection is practiced for a long time …

Gymnosperms are seed producing plants which do not produce any covering surrounding seed. Cycas and Gnetum are two example of Gymnosperms that are respectively considered as primitive and advanced species. In this article, Primitive characters of Cycas and advanced ones of Gnetum will be discussed explicitly. CYCAS Cycas is a …

The genes of nuclear chromosome have a significant and key role in the inheritance of almost all traits from generations to generations,but altogether they cannot be considered as the sole vehicle of inheritance because certain experimental evidences suggest the occurance of certain extranuclear genes or DNA molecules in the cytoplasm …

In order to grow, cells have two options. They must either replicate themselves to create more cells, or the cells themselves must expand in volume. In humans, tissues such as the skin and blood contain cells that are actively dividing, while other tissues such as fat contain cells that expand. …

In the soil, there are different kinds of constitunets. These properties are divided into two major types- solid and solution. This composition of soil solids and soil solution is discussed in this article.   Chemical Composition of Soil Solids Soil Solid consists of soil mineral matter and soil organic matter. The …

Soil- a very common word to all of us living in this universe. You must have seen, even touched soil. But do you ever thought about what component/s are jot down to make such a major element of our environment? Soil is basically a mixture of few basic components- inorganic …

Gymnosperms are vascular plants that reproduces by means of an exposed seed, or ovule—unlike angiosperms, or flowering plants, whose seeds are enclosed by mature ovaries, or fruits. The seeds of many gymnosperms (literally “naked seeds”) are borne in cones and are not visible until maturity. So far Taxonomists have recognized 88 genera and more …

Photosynthesis is a chemical reaction that takes place inside a plant, producing sugar type food for the plant to survive. Carbon dioxide, water and light are all needed for photosynthesis to take place. It happens in the leaves of a plant and the other green portions as well. The process of photosynthesis …

Many systems of classification of Gymnosperms have been proposed by different authors. According to the Classification of  Sporne (1965), Gymnosperms are classified into three classes. Among them, Gnetopsida is the third one. In this article, the only order of Gnetopsida is discussed in detail. Related articles Orders of Coniferophyta Orders of …