The food we eat provides us with proteins, fats, carbohydrates, vitamins, and minerals, all of which are necessary for growth, development, and health. Various crops require different climatic conditions, temperatures, and photoperiods for their growth and development. Plants depend on sunlight for growth. Photoperiods are associated with solar time.

For successful crop production, you need to understand how crops grow and mature. You also need to understand how different nutrients, water, and climate affect the growth of the plant. You need to administer and modify each factor to increase the yield of your crop.

• Crops grown during the rainy season (the Kharif season, between June and October) are known as Kharif crops. Example: maize, cotton, green gram, paddy, soybean, pigeon pea, and black gram are Kharif crops.
• The crops which are grown in the winter season (from November to April) are called rabi crops. Example: Wheat grain, mustard, peas, and linseed are rabi crops.

Crop variety improvement: It can be done either by hybridization or by introducing a gene.

(i) Crop improvement by hybridization: The term 'hybridisation' refers to the crossing of genetically dissimilar plants. This crossing may be interparietal (between different varieties), interspecific (between two different species of the same genus), or intergeneric (between different genera).

(ii) Crop improvement by instigating a gene: This provides the desired characteristics and results in genetically modified crops.

Cultivation practises and crop yield are related to weather, soil quality, and availability of water. Since weather conditions such as drought and flood situations are uncertain, varieties that can be grown in varied climatic conditions are useful.

Variety improvements can be done for:

(i) Higher yield: To increase the yield of crop per acre.

(ii) Improved quality: The quality of crop products varies from crop to crop. Example, the protein quality is important in pulses, oil quality in oilseeds, preserving quality in fruits and vegetables.

(iii) Biotic and abiotic resistance: Biotic factors are insects, diseases, and nematodes while abiotic factors are waterlogging, drought, salinity, heat, cold, and frost which influence crop productivity. Varieties resistant to these factors can be improved to increase crop production.

(iv) Change in maturity duration: A shorter maturity period of the crop reduces the cost of crop production and makes the variety more economical. Constant maturity makes the harvesting process trouble-free and reduces losses during harvesting.

(v) Wider adaptability: It facilitates the crops to be grown under different climatic conditions in distinct areas.

(vi) Agronomic characteristics that are desirable: They increase productivity. For example, tallness and profuse branching are desirable characteristics for fodder crops; while dwarfness is desirable for cereals because they consume fewer nutrients.

Plant nutrients: Nutrients are supplied to plants by air, water, and soil. Sixteen nutrients are essential for plants. Carbon and oxygen come from air, hydrogen comes from water, and the other thirteen nutrients come from soil. Of these thirteen nutrients, six are required in large amounts and are therefore called macronutrients. The other seven nutrients are used in small quantities by plants and are therefore called micronutrients.

Nutrients supplied by air, water, and soil: The air, water and soil supply plants with two nutrients namely carbon and oxygen. The water and soil supply thirteen nutrient elements.

Manure: Manure consists plenty of organic matter and supplies small quantities of nutrients to the soil. The decomposition of animal excreta and plant waste produces manure. Manure aids in improving the soil with nutrients and organic matter and increasing soil fertility. Based on the type of biological waste used to make manure, it can be classified into three types: (i) Compost (ii) Vermicompost (iii) Green manure.

(i) Compost: It can be farm waste material such as livestock excreta (cow dung etc.), domestic waste, sewage waste, vegetable waste, animal refuse, eradicated weeds, straw, etc. Composting is the process of decomposing this material in pits. Organic matter and nutrients are abundant in this compost.

(ii) Vermicompost: The compost which is made by the decomposition of plant and animal refuse with the help of redworm is called vermicompost.

(iii) Green manure: A green manure is made by growing plants like sun hemp and guar, and plowing them into the soil before dispersing the seeds. These green plants thus turn into green manure which helps in improving soil with nitrogen and phosphorus.

Fertilisers: Fertilisers are lucrative plant nutrients. Fertilisers provide phosphorus, nitrogen, and potassium. They are used to secure quality vegetative growth giving rise to healthy plants. Fertilisers are an salient factor in the higher yields of high-cost farming.

Organic farming: As a farming system, it uses little to no chemicals such as fertilizers, pesticides, herbicides, etc. and with a maximum input of organic manures, use of bio-agents such as the culture of blue-green algae, recycled farm-wastes (straw and livestock excreta) in preparation of biofertilizers, neem leaves or In grain storage, turmeric acts as a biopesticide with healthy crop systems. These cropping systems are beneficial in pest, insect, and weed control besides providing nutrients.

Irrigation: Conventional irrigation is very important for the favourable outcomes of crops. Making sure that the crop gets water at the right stages during its growing season, can increase the expected yield of a crop. Various types of irrigation systems include wells, canals, rivers, and tanks.

(i) Wells: These are of two types namely tube wells and dug wells. Water is collected from water-bearing strata in dug wells whereas, tube wells can tap water from the deeper strata. Pumps lift water from these wells.

(ii) River lift system: Region where canal flow is inadequate or irregular due to insufficient reservoir release, the lift system is more logical. Water is directly drawn from the rivers for augmenting irrigation in areas near to rivers.

(iii) Tanks: Small storage reservoirs, which seizes and store the run-off of smaller drainage areas.

Cropping patterns: It includes different ways of growing crops to get the maximum benefit. These different ways include the following:

(i) Mixed cropping: Mixed cropping is the practice of growing several crops at the same time on a piece of land. For example wheat and gram, wheat and mustard, and groundnut and sunflower. This reduces disease risk and provides some protection against one crop failing.

(ii) Inter-cropping: It involves growing two or more crops simultaneously on the same field in a definite proportion or pattern. Several rows of one crop alternate with a few rows of another. For example, finger millet (bajra) + cowpea (lobia), soybean + maize. Crops are selected based on their nutrient requirements. This ensures maximum use of nutrients and prevents pests and diseases from spreading to all of the plants in a field of a single crop. In this way, both crops can provide better returns.

(ii) Crop rotation: Crop rotation is when different crops are planted on a plot of land in succession according to a predetermined timetable. Various combinations of crops are rotated depending on the time scale. The availability of moisture and irrigation facilities determine the choice of the crop to be cultivated after one harvest. With proper crop rotation, two or three crops can be grown in a year with a good harvest.

1. The food required to support the animals to live a healthy life, and 
2. milk-producing requirement, which is the type of food required during the nurseling period.

Weeds: Weeds are unwanted plants in the cultivated field, for example, Xanthium (Pokhran), Parthenium, and Cyprinus rotundus. They compete for food, space, and light. Weeds take up nutrients and reduce the growth of the crop. So, the elimination of weeds from cultivated fields throughout the early stages of crop growth is crucial for a good harvest.

Techniques of weed control: The most productive method is mechanical removal. Preventive methods such as proper seedbed preparation, finely sowing of crops, inter-cropping, and crop rotation also help in weed control.

Insect pests: Normally, insect pests attack the plants in three ways: 

(i) The root, stem, and leaf are cut

(ii) Plant cells are sucked for their sap

(iii) They perforate into stem and fruits, thus affecting the health of the crop and reduce yields.

Preventive measures against pests include:

(i) The use of disease-resistant varieties.

(ii) Growing several crops at the same time on the same field.

(iii) Summer ploughing: In this method, fields are ploughed deep in summer to destroy both pests as well as weeds.

Animal husbandry is the scientific management of animal livestock. It includes various features such as breeding, feeding, and disease control. Animal-based farming includes sheep, cattle, goat, poultry, and fish farming.

Animal feed includes: (a) Roughage, which is large, fibre, and (b) Concentration which are low in fibre and contain relatively high levels of protein and other nutrients.

The enhanced poultry breeds are evolved for the following advantageous traits:

(i) Number and quality of chicks.

(ii) Dwarf broiler parent for commercial chick production.

(iii) Summer adaptation capacity.

(iv) Low maintenance requirements.

(v) Limiting the size of the egg-laying bird 

Production of poultry birds: For good production of poultry birds, good management practises are important. These include conservation of hygienic conditions in housing and poultry feed, as well as prevention and control of diseases and pests. Broilers need a diet rich in protein and fat. The level of vitamins A and K is kept high in the poultry feeds.

Fish Production: There are two ways: 

(i) Capture fishing, obtained from natural resource

(ii) Culture fishery, obtained from fish farming

Popular marine fish varieties include Bombay duck, Pomfret, mackerel, tuna, and sardines. Marine fish of high economic value includes prawns, mussels, mullets, bhetki pearl spots, and oysters. 

Fish resources are of two types:

(a) Freshwater resources such as ponds, reservoirs, canals, and rivers.

(b) Brackish water resources such as estuaries and lagoons.

In such a system, a combination of five or six species is used in a single fishpond. These species are selected so that they do not compete for food among them having different types of food habits.