Table of Contents
Introduction
- Soil and climate play pivotal roles in the growth, development, and productivity of horticultural crops.
- Fruit growers must possess comprehensive knowledge about the impact of various soil and climatic conditions on fruit cultivation.
- Horticulture crops cannot be grown in all types of soil and climate, necessitating zone-wise cultivation practices.
- Climate encompasses factors like temperature, rainfall, atmospheric humidity, wind, hail, and light, while soil encompasses moisture supply, texture, chemical composition, and soil temperature.
Soil
- Soil is the primary growing medium for crops, providing mechanical support, nutrients, and water for plant growth.
- Efficient root development requires soils with adequate air supply, water availability, and low bulk density.
- Most horticultural crops thrive in well-drained soils and cannot tolerate waterlogging conditions.
- Deep, well-drained soils, free from hard subsoils, are ideal for plant growth and development (Brady & Weil, 2008).
Classification of Soils
Alluvial Soils
- Widespread in India, covering an area of 143 sq. km, particularly in the northern plains and river valleys.
- Highly fertile due to the presence of humus, lime, and organic matter.
- Light grey to ash grey in color, with a sandy to silty loam texture.
- Rich in potash but deficient in phosphorus (Dudal, 1965).
Black Soils (Regur or Cotton Soils)
- Known for their mature nature and high water-retaining capacity.
- Swell when wet and shrink when dried.
- Rich in iron, lime, calcium, potassium, aluminum, and magnesium, but poor in nitrogen, phosphorus, and organic matter.
- Color ranges from deep black to light black, with a clayey texture (Bhattacharyya et al., 2007).
Red Soils
Found in low-rainfall areas of the eastern and southern parts of the Deccan Plateau.
Poor in nitrogen, phosphorus, and humus.
Develop a reddish color due to the presence of iron and turn yellow when hydrated.
Generally fertile, except in dry upland areas where fertility decreases (Challa et al., 1995).
Laterite Soils
- Develop in areas with high temperature and high rainfall.
- Low humus content due to the destruction of microorganisms, particularly decomposers, by high temperatures.
- Suitable for cultivation with adequate manures and fertilizers (Pal et al., 2014).
Arid Soils
- Commonly found in the state of Rajasthan.
- Generally brown in color, with increasing calcium content in lower horizons, leading to the formation of “kankar” layers.
- Rich in salt content.
- Become suitable for cultivation after proper irrigation (Singh & Kar, 2001).
Saline Soils
- Contain a large proportion of sodium, potassium, and magnesium salts.
- Lack nitrogen and calcium.
- Poor in fertility, with high salt content due to dry climate and poor drainage.
- Occur in arid, semi-arid, waterlogged, and swampy areas.
- Gypsum is added to the soil to alleviate salinity problems (Qadir et al., 2008).
Forest Soils
- Loamy and silty on valley sides, and coarse-grained in upper slopes.
- Acidic in cooler parts of the country, with low humus content.
- Heavy and black in color.
- Found in hilly and mountainous areas with sufficient rain forests.
- Soils in lower valleys are fertile, with varying structure and texture depending on the environment (Brady & Weil, 2008).
Fruits According to Salinity Tolerance
- High salt tolerance: Date palm, ber, aonla
- Medium salt tolerance: Pomegranate, fig, grape
- Low salt tolerance: Apple, orange, almond, lemon, avocado
Considerations for Soil Selection in Fruit Crops
Physical properties should be emphasized more than chemical properties, as the latter can be improved through external inputs.
Depth and drainability are crucial considerations for fruit crop cultivation (Landon, 1991).
Maintaining Soil Health for Sustainable Production
- Conduct soil analysis to determine physical and chemical attributes.
- Improve soil potential by applying organic matter, chemical fertilizers, micronutrients, and amendments based on soil analysis reports.
- Adopt soil conservation techniques like green manuring on a regular basis.
- Implement improved water management techniques like drip irrigation and check basin or furrows.
- Incorporate large quantities of bulky organic matter annually.
- Create appropriate drainage around the plot.
- Remediate salinity issues by scraping salts and applying gypsum, iron pyrites, pressmud, etc., regularly.
- Replenish nutrients harvested by the crop through a balanced nutrient management approach.
- Recycle organic waste.
- Protect and improve soil, as it is the most crucial natural resource for fruit cultivation (Brady & Weil, 2008).
Climate
Light
Climate is the average atmospheric phenomena for a specific region, calculated over a period of 30 years. Light, water, temperature, and air are essential determinants of climate.
Plants react to electromagnetic radiation within the wavelength range of 4000 to 7700 angstrom units (400-770 nanometers).
Light is essential for photosynthesis and, consequently, plant growth and development.
Light intensity and duration (photoperiod) are crucial factors influencing plant development.
Light intensity can be estimated from the number of hours of bright sunlight or the cloudiness of the sky.
Horticultural crops generally require ample sunlight, but some crops like turmeric and ginger can tolerate shade.
Young mangosteen, coffee, cocoa, and tea need partial shade during their development stages, while crops like palm, duku, and carambola require permanent shade (Larcher, 2003).
Photoperiodism
- Photoperiod, or day length, can significantly influence flowering in plants.
- Based on their response to photoperiod, plants are classified into nine categories (Vince-Prue, 1975):
- Long-day plants: Cabbage, cauliflower, onion, beet, radish, carrot, spinach, potato, dill, plantago
- Short-day plants: Strawberry, pineapple, chrysanthemum, poinsettia, aster, balsam, salvia, euphorbia, xanthium
- Day-neutral plants: Tomato, most fruit crops, pepper, cucumber, snapdragon, mirabilis, certain pea varieties
- Consideration of photoperiodic requirements is crucial for flowering and fruiting in photosensitive crops.
Heat (Temperature)
Heat is a non-mechanical energy transfer related to the temperature difference between a system and its surroundings.
Temperature is measured using thermometers, and daily, monthly, and yearly averages, as well as mean low and high temperatures and extremes, are computed.
At sea level on the equator, the yearly average temperature is around 26-27°C, with a small range of 2-3°C between months and 6-10°C between day and night.
Temperature range increases with distance from the equator and altitude, with a decrease of approximately 5-6°C for every 1000 m increase in altitude.
- Plant growth is primarily dependent on temperature, exemplified by the extended growth cycle of ‘Lacatan’ banana at higher altitudes compared to sea level.
- Availability of heat units determines the suitability of a crop for a given location, and the average temperature provides an idea about the available heat units (Peng et al., 1995).
- Temperate fruit crops like apple, pear, peach, plum, and almond undergo dormancy due to short day conditions and require varying lengths of chilling (temperatures below 7°C) to break dormancy, typically ranging from 250 to 1000 hours (Westwood, 1993).
- Frost and chilling temperatures are harmful to tropical and subtropical plants, while extremely high temperatures found in arid regions can cause wilting, sunscald, necrotic spots, and even plant death (Wahid et al., 2007).
- In such conditions, appropriate crop selection and provision of protection measures become crucial.
Water
- Water is a transparent, odorless, and tasteless liquid compound of hydrogen and oxygen (H2O), essential for plant growth and development.
- It acts as a substrate in photosynthesis, regulates plant temperature, and distributes metabolites and nutrients.
- Water is supplied through precipitation in the form of rain and snow.
- Near the equator, total rainfall can reach up to 2000 mm per year, but decreases with distance from the equator, influenced by factors like mountain ranges.
- For crop production, the distribution of rainfall is more important than the total amount, and in the Indian subcontinent, rainfall is primarily confined to the June-September period (Pradhan et al., 2013).
- Fruit cultivation in India relies on irrigation or the selection of crops whose fruiting coincides with water availability periods, while trees remain dormant during stress periods.
Atmospheric Humidity
- Atmospheric humidity, or water vapor present in the air, also influences plant growth and development.
- Low humidity has drying effects and increases water requirements, while high humidity favors fungal diseases.
- Plants requiring high humidity: Sapota, banana, mangosteen, jackfruit, breadfruit.
- Plants requiring low humidity (dry conditions): Ber, grape, date palm, pomegranate, citrus, annona, guava (Steduto et al., 2012).
Air
- Air is a mixture of oxygen, nitrogen, and other gases that form the Earth’s atmosphere.
- Air quality, if polluted by the accumulation of gases like hydrocarbons, SO2, CO2, CO, NO, ethylene, and methane, can adversely affect plant growth.
- Wind movement (air flow) can cause significant damage to crops in deserts, coastal areas, and valleys, necessitating the provision of windbreaks and shelterbelts in such situations (Grace, 1977).
- Storm winds have a speed of approximately 50 km/hr, while hurricane winds exceed 100 km/hr.
Horticultural Zones of India
- The Indian subcontinent is blessed with a great variety of climatic and soil conditions, broadly divided into tropical, subtropical, and temperate regions.
- Considering rainfall, humidity, altitude, and other factors, six different horticultural zones have been identified for appropriate crop selection and development planning (Chadha & Shikhamany, 1999):
- Temperate: Kashmir, Ladakh, parts of Uttarakhand, Sikkim, and parts of Arunachal Pradesh.
- Northwest Subtropical: Punjab, Haryana, Rajasthan, Central Uttar Pradesh, and North Madhya Pradesh.
- Northeast Subtropical: Bihar, Jharkhand, Assam, Meghalaya, Nagaland, Manipur.
- Central Tropical: South Madhya Pradesh, Chhattisgarh, Gujarat, Maharashtra, Odisha, West Bengal.
- Southern Tropical: Karnataka, Andhra Pradesh, Tamil Nadu.
- Coastal Tropical Humid: Konkan, Goa, Kerala, Western Ghats, Eastern Ghats in Tamil Nadu, Andhra Pradesh, and Odisha.
- Selecting the most adaptable crop based on climate and soil is crucial for exploiting the crop’s potential and ensuring sustainable cultivation, as inappropriate choices can lead to difficulties in crop management and increased production costs (Chadha & Shikhamany, 1999).
Climatic Requirements for Important Fruit Crops in India
- Mango: Suitable for tropical and subtropical climates.
- Citrus: Tropical climate, but can also be grown in temperate regions.
- Grapes: Temperate climate, but can be grown in tropical and subtropical regions.
- Peaches: Temperate climate, but low-chilling varieties can be grown in subtropical conditions.
- Sapota: Tropical climate, but low-chilling varieties can be grown in frost-free zones.
- Papaya: Tropical and mild subtropical climates.
- Banana: Tropical climate, but can be grown in subtropical regions provided they are frost-free.
- Almond: Temperate climate, but some low-chilling varieties can be grown in subtropical climates.
- Apple: Temperate climate, but some low-chilling varieties can be grown on lower hills (Chadha & Shikhamany, 1999).
Classification of Vegetable on season
- Warm Season Vegetables: Bottle gourd, watermelon, eggplant, tomato, cluster bean, okra, sweet potato.
- Cool Season Vegetables: Cabbage, cauliflower, peas, beans, potato, onion, carrot, radish.
Classification of Flower Crops on season
- Warm Season Flowers: Marigold, zinnia, chrysanthemum, sunflower, gomphrena, gaillardia, portulaca, kochia, amaranthus, celosia, coreopsis.
- Cool Season Flowers: Aster, poppy, dianthus, dahlia, salvia, petunia, pansy, phlox, coreopsis, verbena, dimorphotheca, calendula, brachycome, candytuft, sweet alyssum, antirrhinum, sweet pea (Chadha & Shikhamany, 1999).
