Agriculture

Who Is and What Did Gregor Mendel Contribute to the Science of Genetics?

Gregor Mendel is now popularly called the Father of Genetics.

The title is just fitting for one who founded the basic principles of heredity and variation in living organisms.

He did not know it during his lifetime, but he was destined to become one of the most influential persons in the growth of biology.

In 1962, James Watson, Francis Crick, and Maurice Wilkins jointly won the highly coveted Nobel Prize for having discovered the structure of DNA, the “secret of life.”

Rosalind Franklin would also have shared the prize had she lived (Phelan 2006). (Click here to read a surprising update on Watson’s and Crick’s Nobel prize medals).

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Contribution to the History of Photosynthesis: Johann Baptista Van Helmont and John Woodward

Johann Baptista van Helmont (1577-1644) was a Belgian chemist and physician.

He was born in Brussels, obtained his medical degree from the University of Louvain, and returned to Brussels to practice medicine.

He moved later to Vilvorde and stayed there until his death.

His work on chemical research made him infamous to the Inquisition and he was imprisoned for two years (Rook 1964).

He started the inquiry which ultimately leads to the abandonment of the Humus Theory and to the understanding of the physiological process now called photosynthesis.

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Methods of Planting Crops: I. What Is Direct Seeding and What Is Transplanting?

Various methods of planting are practiced in crop farming.

These can be put under broad classifications such as direct seeding vs. transplanting, direct planting vs. indirect planting, and manual vs. mechanized planting.

This page is about the first alternative methods as applied mainly to crops that can be grown from seeds.

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What Is Photoperiod? It Varies From Place to Place

Photoperiod, also called light duration and day length (or daylength), refers to the length of the light period as contrasted to the darkness within a day.

Day length controls or influences several plant growth and development processes that determine or affect crop yield.

The difference in day length can have a marked influence on the establishment and yield of certain crops.

As already mentioned, giant potatoes and cabbages have been produced in Alaska (about 61°N) during summer when light is intense and almost continuous.

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What Are Seed Plants, Angiosperms, and Gymnosperms

Seed plants or seed-bearing plants, also called spermatophytes or Spermatophyta, are vascular plants with numerous members belonging to the lignophytes or woody plants.

They have the natural ability to produce seeds, a characteristic that likewise distinguishes them from earlier plants.

The seed has been defined as an embryo surrounded by nutritive tissue and enveloped by a seed coat.

The embryo is an immature diploid sporophyte developing from the zygote (Simpson 2010).

Those which do not produce seeds are called seedless plants or non-seed plants.

They consist of both nonvascular and vascular plants and reproduce by means of spore.

The spore is defined by Simpson (2010) as a haploid cell that, in the land plants, originates from meiotic divisions of sporocytes within a sporangium, ultimately growing into a gametophyte.

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Environmental Factors Affecting Transpiration, the Same Climatic Factors in Crop Growth, Development, and Productivity

Enumerated below are the environmental factors affecting transpiration in plants.

These factors are described as “environmental” to distinguish them from those genetic factors which are inherent in the plants.

They are also described as external factors, that is, outside of or external to plants.

Specifically, they are climatic factors, that is, they are elements of the climate.

These factors are the same climatic factors that can either promote or inhibit plant growth and development and, eventually, crop productivity.

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The Different Types of Vegetables, Grouping Based on Edible Botanical Organs

First, what are vegetables and how many types of vegetables may there be?

For clarity, the term vegetables or vegetable crops is here meant to refer to a classification of agricultural crops under horticulture.

These crops are plants having edible parts that are used in culinary preparations either cooked or raw, as in salad recipes.

Fruit vegetables: cucumber, string bean, eggplant, okra and squash; and carrot as root vegetable
Fruit vegetables: cucumber, string bean, eggplant, okra, and squash; and carrot as a root vegetable

As to how many types, groupings, or classifications of vegetables are there, there can be no definitive answer.

Just like food recipes, there can be too many.

The classifications can vary depending on various considerations such as the taxonomic classifications of the crops (e.g., by family or by genus), the part of the plant that is edible (e.g., root vs. stem), and its stage of development (mature vs. young), their particular use in culinary preparation (for example, cooked vs. uncooked), the degree of detail that any distinction seeks to express, and who talks to who.

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Types of Photosynthesis: II. C4 Photosynthesis

C4 Photosynthesis. This mechanism of photosynthesis occurs in two adjoining types of cells, the mesophyll and bundle sheath cells in plant species called C4 plants.

Both C3 and C4 cycles operate in the non-light-requiring or Dark Reactions of photosynthesis but spatially, that is, in different cells: C4 in the mesophyll cells immediately followed by C3 cycle in the bundle sheath cells.

CO2 first enters the leaf and into the mesophyll cell.

It is then hydrated to produce bicarbonate ion (HCO3-) in the cytoplasm with carbonic anhydrase (CA) as catalyst.

This is the first step in C4 photosynthesis, followed by carboxylation reaction utilizing HCO3- instead of CO2 as the inorganic carbon substrate, Hatch and Burnell (1990) emphasized.

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Caveat: Common Plant Nameshow We Propagated Sampaguita by Leaf Cuttings

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The jasmine or Sampaguita also spelled sampagita and scientifically known as Jasminum sambac, is a popular plant because of the pleasing fragrance that its flowers emit.

This fragrance is due to the presence of essential oil.

Discovered: sampagita or jasmine can be propagated by leaf cuttings
Discovered: Sampagita or jasmine can be propagated by leaf cuttings

Essential oils are mixtures of substances that contain the essence, or odor, of the plant.

They are extracted from flowers and other plant parts and used in the manufacture of perfumes and cosmetics.

The principal volatile constituent of an essential oil usually belongs to a family of chemical compounds called terpenes.

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Caveat: Common Plant Names

Common plant names or common names of plants, also called vernacular names, local names, and country names, are the names used to refer to specific plants as contrasted to scientific names, botanical plant names, or Latin names.

Their usage may be restricted to a small tribe having a unique dialect, a province, a region, or a country.

Others, often in English, are used with wide international recognition, such as rice, coconut, and banana.

Many publications separate the English common names from the vernacular names, for example, Common names: rice (Engl.), palay (Tag.), humay (Ceb.).

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