Crop Classification: Types, Examples & Uses Explained

A crop is an organism that is cultivated and harvested to obtain a yield. According to the natural system, the Plant Kingdom is divided into two divisions: Cryptogams and Phanerogams. Phanerogams are further divided into two subdivisions: Angiosperms and Gymnosperms.

Angiosperms are divided into two classes, Monocotyledonous and Dicotyledonous. These classes are then divided into orders, orders into families, families into genera, and species into genera and species, and sometimes species into varieties.

Classification of Crops or Plants

Classifying crops or plants helps us to become familiar with their specific requirements, such as the appropriate soil and water conditions, adaptability, growing habits, and climatic needs.

It also enables us to understand the economic production and usage of crop plants, as well as their growing seasons. In summary, crop classification provides valuable knowledge about the optimal conditions necessary for successful cultivation.

Classification Based on Climate

Tropical climate crops grow well in warm and hot climates, for example, rice and sugarcane, among others.

Temperate crops grow well in a cool climate, for example, wheat, oats, gram, and potatoes, among others.

Classification Based on The Growing Season:

Rainy crops are grown from June to November during the monsoon months. These crops need warm and wet weather during their growth period and short day lengths for flowering. Examples of such crops are cotton and rice.

Cold-season crops, on the other hand, grow well during the winter season, from October to March. These crops require cold and dry weather and longer day lengths for flowering. Examples of such crops include wheat, gram, and sunflower.

Summer crops are grown in the months of March to June, and require warm weather during the major growth periods and longer day lengths for flowering. Groundnuts, watermelons, pumpkins, and gourds are examples of summer crops.

Agronomic Classification of Crops:

1. Grain crops: refer to cultivated grasses grown for their edible starchy grains, such as cereals like millet. The larger grains, such as rice, wheat, maize, barley, and millet, are used as staple foods, while small-grained cereals like millet are of minor importance as food.
2. Pulse/legume crops are leguminous crops whose seeds are used as food. On splitting, they produce crops rich in protein, such as green gram, black gram, soybean, pea, and cowpeas, among others.
3. Oilseed crops are crops whose seeds are rich in fatty acids and are used to extract vegetable oil to meet various requirements. Examples include groundnut, mustard, sunflower, sesamum, and linseed.
4. Forage crops: refer to vegetative matter, fresh or preserved, utilized as food for animals. Crops are cultivated and used for fodder, hay, and silage, such as sorghum, elephant grass, guinea grass, and other pulses.
5. Fiber crops are grown for their fiber yield, which may be obtained from seeds, such as cotton.
6. Root crops are crops whose economic production is in their roots. Examples include sweet potatoes and carrots, among others.
7. Tuber crops are crops whose edible portion is not a root but a short, thickened underground stem. Examples include potatoes and yams.
8. Sugar crops: refer to the two important crops, sugarcane and sugar beet, which are cultivated for the production of sugar.
9. Starch crops are grown for the production of starch. Examples include tapioca and sweet potato.
10. Dreg crops are used for the preparation of medicines, such as tobacco, mint, and pyrethrum.
11. Spices and condiments/spices crops: refer to crops whose products are used to flavor, taste, and sometimes color fresh or preserved food. Examples include ginger, garlic, chili, cumin, onion, coriander, cardamom, pepper, and turmeric, among others.
12. Vegetable crops: may refer to leafy or fruiting vegetables, such as tomatoes.
13. Green manure crops are grown and incorporated into the soil to increase soil fertility.
14. Medicinal and aromatic crops: refer to medicinal plants, such as cinchona, and aromatic plants, such as lemon grass, citronella grass, mint, peppermint, rose, jasmine, and henna, among others.

Classification Based on The Life Cycle/Duration :

Seasonal crops, such as rice and wheat, complete their life cycle within a single season, which is typically summer. In contrast, there are two seasonal crops, such as cotton, turmeric, and ginger, which require two seasons to complete their life cycle.

Annual crops, like sugarcane, require a full year to complete their life cycle. Biennial crops grow in one year and flower, fructify, and perish the next year. Examples of biennial crops include bananas and papaya.

Perennial crops, such as fruit crops including mango and guava, live for several years.

Classification Based on Cultural Method/Water:

Rain-fed crops grow only on rainwater. Irrigated crops grow with the help of irrigation water, for example, Chili, sugarcane, Banana, and papaya, among others.

Classification Based on Root System:

A taproot system has a main root that grows deep into the soil. Examples of crops with taproot systems include grapes and cotton, among others.

In contrast, adventitious or fiber-rooted crops have shallow, fibrous roots that spread into the soil. Examples of crops with adventitious or fiber-rooted systems include cereal crops, such as wheat and rice, among others.

Classification Based on Economic Importance:

Cash crops, such as sugarcane and cotton, are grown for the purpose of earning money.

On the other hand, food crops, including wheat and rice, are grown to produce food grain for the population and fodder for cattle, among other purposes.

Classification Based on The Number of Cotyledons:

Monocots or monocotyledons are crops with one cotyledon in the seed, for example, all cereals and millet, while Dicots or dicotyledonous are crops having two cotyledons in the seed, for example, all legumes and pulses.

Classification Based on Photosynthesis (Reduction of Carbon Dioxide /Dark Reaction):

(a) C3 Plants:

Wheat, oats, rye, and orchardgrass are examples of C3 plants that use the C3 cycle to fix carbon from carbon dioxide into 3 carbon sugars. Photorespiration is high in C3 plants, which results in lower water use efficiency.

The initial product of C assimilation in these plants is the three 'C' compounds, and the enzyme involved in primary carboxylation is ribulose-1,-biophosphate carboxylase. Examples of C3 plants include rice, soybeans, wheat, barley, cotton, and potatoes.

(b) C4 Plants:

C4 plants fix carbon by producing four-carbon compounds such as malic acid or acetic acid. Phosphoenol pyruvic acid carboxylase is responsible for carboxylation and has a high affinity for carbon dioxide, resulting in negligible photorespiration.

C4 plants have higher photosynthetic rates than C3 plants for the same amount of stomatal opening, making them more drought-resistant. Corn, sorghum, sugarcane, millet, and switchgrass are examples of C4 plants.

(c) Cam Plants:

Cam plants, such as sedum, kalanchoe, pineapple, opuntia, and snake plants, open their stomata at night to fix a large amount of carbon dioxide as malic acid, which is stored in vacuoles.

During the day, stomata are closed, and carbon dioxide stored as malic acid is broken down and released. These plants have negligible transpiration and are highly drought-resistant, like pineapple, sisal, and agave.

C4 and CAM plants have high water-use efficiency.

Classification based on The Length of Photoperiod Required For Floral Initiation:

Most plants are influenced by the relative length of day and night, particularly regarding floral initiation. This effect on plants is known as photoperiodism, which depends on the length of the photoperiod required for floral ignition.

There are three categories of plants based on their photoperiodic response.

Short-day plants, such as rice, green gram, and black gram, initiate flowering when days are shorter than ten hours.

Long-day plants, such as wheat and barley, require longer days, more than ten hours, for floral ignition.

Day-neutral plants, such as cotton and sunflower, are not influenced by photoperiod, and their rate of flowering initiation depends on the duration of the photoperiod.

Note: In short-day plants, shorter days result in more rapid initiation of flowering, whereas in long-day plants, longer days lead to more rapid initiation of flowering.

Factors That Affect Crop Growth

Water, light, nutrients, and temperature are the four key factors that affect plant growth hormones, which in turn determine the speed of growth. Modifying any of these factors can cause stress to the plant, leading to changes or stunted growth, or improved growth.

Factors of Crop Production

Soil fertility, water availability, climate, and diseases or pests are the four most important factors that influence crop yield. Failure to monitor and manage these factors correctly can pose significant risks to farms.

Internal or Genetic Factors

Terrain, climate, soil properties, and soil water are the internal or genetic factors that affect crop growth and production. The genetic makeup of crops varies, and breeders attempt to incorporate the maximum desirable characteristics into one strain while exploiting hybrid vigor.

These desirable traits include high-yielding ability, early maturity, resistance to lodging, drought, flood, and salinity, tolerance to insects and diseases, the chemical composition of grains, quality of grains and straw, and more.

These traits are inherent and transmitted from one generation to the next by genes.

External or Environmental Factors

External or environmental factors affecting crop growth include water, wind, sunlight, temperature, rainfall, photosynthesis, microbes that increase soil fertility, and pollinating agents.

Edaphic or Soil Factors

Edaphic or soil factors that affect crop growth include water stress (flooding and drought), temperature (extreme cold and heat), nutrient deficiency and toxicity (major and minor elements), soil pH (acidic or salinity), excess light, and mechanical stress.

Soil is a thin layer of the Earth's crust that serves as a natural medium for plant growth. It is formed from parent rock by the process of weathering over a long period due to rainwater, temperature, and plant and animal residues.

A vertical cut of 1.5 to 2 m deep soil indicates a layer varying from a few cm to about 30 cm of soil, called surface soil, elbow that a layer of subsoil, and at the bottom, the unrecompacted material, which is the parent rock.

Conclusion

In conclusion, the classification of crops plays a crucial role in understanding their specific requirements and optimizing their cultivation. By categorizing crops based on factors such as climate, growing season, agronomic characteristics, root system, economic importance, and photosynthesis process, farmers can gain valuable insights into the optimal conditions necessary for successful crop production. This knowledge enables farmers to provide suitable soil and water conditions, adaptability, and climate conditions for different crops, ultimately leading to improved yields.

Additionally, understanding the factors that affect crop growth, such as water, light, nutrients, temperature, and external environmental factors, is vital for managing crop production effectively. Farmers need to consider soil fertility, water availability, climate, and the presence of diseases or pests to ensure high crop yields.

Genetic factors inherent in the crops themselves, as well as external environmental factors, also influence crop growth and production. By carefully monitoring and managing these factors, farmers can mitigate risks and optimize their farming practices.

In the realm of agriculture, knowledge is power. By understanding crop classification and the factors that influence crop growth, farmers can make informed decisions, implement appropriate farming techniques, and maximize their yields. Successful crop cultivation not only ensures food security but also contributes to the economic well-being of farming communities.