eChapters

TROPICAL AND SUBTROPICAL FRUITS

2.1 Mango
 

Mango is considered to be an allopolyploid. The chromosome number is 2n =40. The polyembryonic seedlings of cv. Vellaikolumban, earlier reported to be 2n= 80 was later shown to be a diploid. In Canary Island, a putative tetraploid viz Gomera-1 has been identified.

Floral biology

Flower starts opening early in the morning from 4-7 a.m. and maximum flowers open between 9.30-10.30 a.m. and complete 11 a.m. Dehiscence of anthers takes place at 11.30 a.m. and it continues up to 3.45 p.m. The pollen grains are oval, or triangular or oblong. Stigma becomes receptive even 18 hours before flower opening. Mode of pollination is entomophily; nectar is present to attract the insects.

The flowering duration is usually of short i.e. 2 to 3 weeks. The mango inflorescence or panicle bears mainly two types of flowers - male and perfect. The number of flowers per panicle varies between 1000 to 6000 depending upon the variety and climatic factors. The percentage of perfect flowers varies between 0.74 per cent in Rumani, 16.41 to 55.7 per cent in Neelum and up to 69.8 per cent in Langra.

Horticultural crops include the fruit crops, vegetables, spices, plantation crops, medicinal plants, aromatic plants, commercial flower crops and ornamental plants.

Knowledge on the methods by which these reproduce is of primary importance from the standpoint of plant breeding. Besides, their annual or perennial nature also decides the methods of breeding to be adopted to get desired improvement.

Two divisions of methods of reproduction commonly recognized are:

1. Asexual i.e. vegetative parts of the plants are utilized to produce new individuals.

2. Sexual i.e. gametic fusion, the resultant zygote develops into seed which is utilized to produce new individual.

This group can be further placed in several sub divisions according to the mode of pollination. They are

a. Naturally self pollinated crop - (e.g. tomato, pepper, brinjal) wherein cross pollination occurs less than 4 % only.

b. Often cross pollinated crop- (e.g. chillies, bhendi) wherein though self pollination is more frequent, cross- pollination may occur so frequently that some methods of preventing cross pollination between varieties and strains of different genotypic constitution must be followed throughout the breeding programme.
Common breeding methods can be applied to the above two groups, however, the parents chosen for breeding under often cross pollinated crop need to be selfed for few generations to select desirable, homozygous lines.

Introduction:Jamun (Syzygium cumini) belonging to the family Myrtaceae is a popular indigenous fruits Of India. It is also known as black plum, Indian black cherry, Ram jamun etc. in different parts of India. The tree is tall and handsome, evergreen, generally grown for shade and windbreak on roads and avenues. In India, the maximum number of jamun trees are found scattered throughout the tropical and subtropical regions. It also occurs in the lower range of the Himalayas up to an elevation of 1,300 meters and in the Kumaon hills up to 1,600 meters. It is widely grown in the larger parts of India from the IndoGangetic plains in the North to Tamil Nadu in the South.

Soil:The jamun tree can be grown on a wide range of soils. However, for high yield potential and good plant growth, deep loam and a welldrainedsoil are needed. Jamun can grow well under salinity and waterlogged conditions too.

Climate: Jamun prefers to grow under tropical and subtropical climate. It is also found growing in lower ranges of the Himalayas up to an altitude of 1300 meters. The jamun requires dry weather at the time off towering and fruit setting.

Varieties: The common variety grown under North Indian conditions is “Ram Jarnun”. It produces big sized, oblong fruits, deep purple or bluish-black in color at full ripe stage. The pulp of the ripe fruit is purple pink and the fruit is juicy and sweet. The stone is small in size. The variety ripens in the month of June- July and it is very common both in rural as well as in urban markets.

Botany: Emblica officinalis belonging to the family Euphorbiaceae commonly known as Amla or Indian Gooseberry or Nelli is an important crop with high medicinal value. The fruits have the richest source of vitamin-C (700 mg per 100 g of fruits) and is considered to be good liver tonic. The various preparations using Amla include Chyavanprash, Triphala churna, Brahma Rasayana and Madumegha churna. The fruit is valued as an antiscorbutic, diuretic, laxative, antibiotic and anti-dysentric. Phyllemblin, obtainedfrom fruit pulp has been found to have mild depressent action on central nervous system. It has good demand from the industries for the preparation of various health care products also like hair oil, dye, shampoo, face creams and tooth powder.

Soil: Light as well as medium heavy soils except purely sandy soil is ideal for amla cultivation. The tree is well adopted to dry regions and can also be grown in moderate alkaline soils.

Climate: It is a tropical plant. Annual rainfall of 630-800 mm is ideal for its growth. The young plant upto the age of 3 years should be protected from hot wind during May-June and from frost during winter months. The mature plants can tolerate freezing temperature as well as a high temperature upto 46^OC.

Varieties: The varieties recommended for cultivation are Banarasi, Chakaiya, Francis, NA-4 (Krishna) NA 5 (Kanchan), NA-6, NA-7, NA-10 and BSR-1 (Bhavanisagar).

Botany: Coconut palm (Cocos nucifera) belonging to the family Palmae is a slender palm tree widely distributed throughout the tropical regions,with a size that can vary between 12 to 30 meters high. Each inflorescence is a branched flower cluster (panicle), located at the base of the leaves. Its flowers, male and female (monoecious), can be white to pale yellow. Fruiting occurs throughout the year, and the fruit is a drupe with a dry fibrous mesocarp popularly known as coconut.

Coconut fruit has an ovoid shape, constituted by 3 angles and 3 germination holes at the end, with a size between 20 and 30 centimeters in diameter. Coconut fruit consists of a brown fibrous bark and a hard shell, booking a seed inside. The central cavity of the fruit has an aqueous or milky liquid called coconut water that is a nutritional mixture aimed for coconut to grow. When the fruit ripens , this fluid accumulates fat and it is called coconut juice or milk. The seed of the coconut palm is the second largest known , after the coco-de-mer (Lodoicea maldivica ), that can reach 40–50 cm in diameter and weigh from 15 to 30 kg. The seed of coconut is hollow inside and it is covered with a white pulp, oily and edible.

Medicinal uses:It is said to have analgesic, antirheumatic, antibacterial , anticancer, antioxidant, hypoglycemic, hypotensive and immune stimulating properties. Its oil also has numerous cosmetic applications

Botany: Coffee trees are evergreen shrubs of the rubiaceae family. Coffee of commerce consists of seeds of coffee which when roasted, ground and soaked in hot water yields a fragrant stimulating infusion used for preparing the beverage called Coffee. It is native of America and introduced in India in 1936 near Chickmanglur in Karnataka.

Coffee plants have bright green opposite leaves with smooth margins. Its flowers, white, grow in clusters in the axils of the leaves and are aromatic. From them, fruits are born.They are red drupes with the size of a cherry The outside of the fruit is fleshy and inside it there are two seeds or coffee beans, surrounded by a membranous layer of leathery texture, hence this layer is commonly known as the “parchment”. Some species of trees only produce one seed per fruit are known as “pearl coffee”. In double seed varieties, the two seeds that grow inside each fruit press each other, so they stop the growth in the part which is in contact, so this becomes flat.

Soil and Climate: Coffee arbica comes up well in high altitude from 800 to 1650 meters but -C. canephora Pierre ex A.Froehner adopts well to lower elevations. At high altitude the crop is often late and susceptiable to frost and high winds.Evenly distributed rainfall of 2250 mm is essential. Heavy rainfall is not counducive as it encourages rotting of leaves and plants are easily susceptible to fungal diseases.

Botany: Cashew belongs to the Family Aricardiaceae. A small evergreen tree native of tropical America from Mexico to Peru and Brazil but now cultivated largely in Malabar, Kerala, Karnataka, Tamil Nadu and Andhra Pradesh and to some extend in Maharashtra, Goa, Odisha and West Bengal

The commercial production is mainly confined to India, Mozambique, Tanzania, Kenya; Brazil, Philippines, Malaysia and Sri Lanka.Cashew is an important foreign earning crop of India, remarking second (29%) in the international trade of the nuts. It is a crop of marginal lands and can be grown under rainfed conditions.

Soil and climate: It grows up well in all soils. Red sandy loam is best suited. Plains as well as hill slopes upto 600 - 700 feet elevation are suitable for cultivation. Season: June - December. Propagation: Soft wood grafting, air layer and epicotyl grafting. Requirement of plants: 200 plants/ha. Preparation of field: Pits of 45 cm3 size are dug and filled up with a mixture of soil + 10 kg FYM + one kg neem cake and 100 g Methyl parathion 1.3 %.

Botany: The Cocoa (Theobroma cocoa) belonging to the family Sterculiaceae. Cocoa tree is a shade tolerant, moisture loving, understory rainforest tree. The trees live for up to 100 years, but cultivated trees are considered economically productive for only about 60 years. Naturally Cocao grows to a height of 15 meters, but cultivated trees are trimmed shorter to make harvesting easier. The leaves of Cocoa are smooth bright green, oblong, about 15cm by 8cm. The seeds are encased in a large colourful pod which grows close to tree after a flower. The large pod is green while maturing and turns yellow, orange, red or purple when ripe. They range from about 10 cm to greater than 40 cm in length.

Soil and climate: Potash rich alluvial soils friable in nature with high humus and moisture retentivity with a pH of 6.6-7.0 are suitable. Cocoa is normally cultivated at altitudes upto 1200 m above MSL with an annual rainfall of 150 cm and a relative humidity of 80 % and annual mean temperature of 24^oC to 25^oC. Cocoa can be grown as intercrop in coconut and arecanut gardens.

Botany:Fenugreek is a leguminous plant, belonging to the Papilionaceae family. Fenugreek is an annual herbaceous plant between 20 and 50cm high. (sometimes up to 100cm.). Its stem is erect, branched, grooved and with little pubescence. The leaves are compound, petiolate, oblong leaflets formed by three kills reminding those of alfalfa. White or yellow flowers , isolated or arranged in pairs. Fenugreek fruits are narrow and elongated pods. They contain 10 to 20 seeds, tiny yellow, quadrangular, with a groove in the central part dividing them into two unequal lobes.

Land Requirements: Land to be used for seed production of Kasuri methi and methi shall be free from volunteer plants.

Varieties: Co 1, Pusa Early Bunching, Lam selection 1, Rajendra Kranti, Kissar Sonali, RMT1and CO 2.

Soil: A rich well drained loamy soil is best suited.

Climate: Cool and comparatively dry, frost free climate. It requires a warm climate with mild temperatures for a good seed production (between 8 and 27°C).It grows well in full sun. Sow it in places sheltered from the wind. Resistant to frost and temperatures down to -5°C. However, low temperatures during planting causes not all seeds to germinate.

Season: June - July and October - November.

Botany:Coriandrum sativum belonging to the family Umbelliferae. It is an annual soft shrub that attains a height of 1 to 3 feet. Leaves are in basal cluster varies from 3 to 15 cm in length and are oblong to ovate in shape. Leaflets are 1 to 2 centimeter in length and are ovate to round. Flower is of white color which can vary from light purple to creamish in color. These appear in umbles. Fruit is roundish in shape bearing color that varies from yellow to brown. It is tripped and gets divided in to two then crushed with fingers. The plant flowers and fruits in late winters.

Land Requirement: Land to be used for seed production of coriander should be free from volunteer plants

Varieties: CO 1, CO 2, CO 3, CO (CR) 4, GAU 1, UD 1, UD 2, UD 20 and UD 21

Soil: Well drained black cotton soil and red loamy soil. For rainfed cultivation soil should be clay in nature and the pH should be 6 – 8.Coriander performs well at a temperature range of 20 – 25 °C.

Climate: Cool and comparatively dry, frost free climate

Botany

Phyllanthus is an herb common to Central and Southern India. It can grow to 30–60 centimeters in height and blooms with many yellow flowers. All parts of the plant are employed therapeutically. It is a small erect annual herb 10-60 cm tall widespread in tropical areas. Leaves are small elliptical - oblong and flowers are whitish green & minute. It bears ascending herbaceous branches. The bark is smooth and light green. The fruits are tiny, smooth capsules containing seeds.Kizhanelli is a circum-tropical weed, thriving well under tropical conditions. In India, it grows abundantly up to 700m altitude in Punjab, Haryana, Uttar Pradesh, Bihar, West Bengal, Orissa, Madhya Pradesh, Maharashtra, Andhra Pradesh, Karnataka, Tamil Nadu and Kerala.

Major constituents – Phyllanthin (0.4-0.5%) and Hypophyllanthin

Uses- Hepatitis B and Jaundice

Botany: Senna, Cassia angustifola belonging to the family Leguminosae is a perennial 1-2 m height undershrub. The stem is erect, smooth, and pale green to light brown with long spreading ascending branches. Leaves are compound with four to eight pairs of leaflets. The full grown leaflets are bluish-green to palegreen in colour and emit a characteristic fetid smell when crushed. The flowers are small and yellow and axillary arranged racemes. The pods are broadly oblong about 5-8 cm long and 2-3 cm broad, green in beginning and change to greenish-brown to dark brown on maturity. Each pod has 5 to 7 ovate, compressed, smooth, dark-brown seeds.

Varieties : KKM - 1, Anand Late Selection, ALFT-2 and Sona

Soil and climate: In Tamil Nadu, it is grown in sandy or sandy loam or laterite soils. It is a hardy warm weather crop grown under rainfed and irrigated conditions. Senna is also cultivated successfully on black cotton soils. It has a great tolerance to high soil salinity, however, shedding of some lower leaves often occurs. The soil pH suited for cultivation is 7.0-8.5. But, the most suitable to sandy loam to loam soils which are more friable and well drained.

Botany: Periwinkles (Catharanthus roseus) belonging to the family Apocynaceae are evergreen perennials that produce bright blue flowers. They grow best in well-draining, moist soil and partial sun to full shade. They work well as sprawling groundcover or border plants and bloom from early spring to early fall. Periwinkles are often grown as transplants, but they can be started from seed about 10 weeks before the last frost with the proper care.

Varieties: Nirmal, Dhawal and Prabal

Soil and climate: It is suited to all types of soil and tropical climatic conditions. Well distributed annual rainfall of 100 cm or more is ideal for raising as a rainfed crop.

Seeds and planting: Propagated through seeds either by direct sowing or throughtransplanting.

Seed rate: 2.5 kg/ha : Direct sowing

0.5 kg/ha : Through seedlings

45 - 60 days old seedlings are transplanted at a spacing of 45 x 20 cm during June - July or September - October.

Botany

Ashwagandha (Withania somnifera), also known as Indian ginseng belonging to the family Solanaceae, is an important ancient plant, the roots of which have been employed in Indian traditional systems of medicine, Ayurveda and Unani to cure asthma, fever, chest complaints. It is an erect branching undershrub reaching about 1.50 m in height. It grows in dry and sub-tropical regions. Being hardy and drought tolerant species with its enormous biocompounds, its usage is forever regarded and continuous to enjoy the monopoly in many parts of India, particularly in Madhya Pradesh. It grows in dry parts in sub-tropical regions. Rajasthan, Punjab, Haryana, Uttar Pradesh, Gujarat, Maharashtra and Madhya Pradesh are the major Ashwagandha producing states of the country. Roots are fleshy, tapering, whitish brown. Leaves are ovate and flowers are greenish. The mature fruits are orange-red berries.

Varieties:Poshita and Rakshita are high yielding varieties released by CSIRCIMAP, Lucknow. Jawahar 20 is cultivated in Madhya Pradesh. WSR is another variety released by CSIR-Regional Research Laboratory, Jammu. Nagori is a local variety with starchy roots

Varieties: No named variety

Soil: Red sandy soil and sandy loam soil are highly suitable. Soil drainage is essential and hard pan and water logged soils should be avoided.

Climate: Suitable for plain and lower hills. Requires 70 cm annual rain fall

Propagation: Terminal three to four nodal cuttings measuring 10 cm length is used

Land Preparation: Apply 15 t FYM/ha. Ridges are formed at a spacing of 60 cm. Cuttings have to be planted at a spacing of 45 cm.

Nutrient management: Nutrients Quantity (kg / ha) N 30 P 60 K 50 The above nutrients can be applied in two split doses viz., 30 and 45 days after planting. In micronutrient deficient soils, ZnSO4 can be applied as basal fertilizer.

Pre sowing seed treatment: Fortification with GA3 100 ppm (or) moringa leaf extract 2% for 16 h (or)KH₂PO4 2% for 16 hours

Age of the seedling for transplanting: The seeds are first sown in primary nursery (pot) and after 16 day the seedlings are transplanted to raised nursery and after 24 days transplanted to main field.

Botany :Annual Chrysanthemum is a winter annual that can be grown either as pot plants or in groups as bed plants for various ornamental purposes. There are two types of annual Chyrsanthemums: Chrysanthemum Segetum and C.coronarium. Major varieties of Chrysanthemum segetum L. are Morning Star, Evening Star, Eastern Star, Blanca, Eldorado, Gloria, Isabel, Romeo, and yellow Stone while popular cultivars of C. coronarium L. include Nivea, Oreon, Albo, Golden Crown, Luteum, Tom Thumb Golden Gem, Tom Thumb-Primrose Gem and Tetra Comet. In addition to this, there is another type of annual Chrysanthemum, i.e. C. carinatum. Popular varieties of C. carinatum S. are Merry, Atrococcineum, Burridgeanum, Eclipse, Flammenspiel, John Bright and Northern Star.

Propagation

Annual Chrysanthemums can be propagated by seeds. Their sowing time depends upon climate. It varies in different parts of India. In the Northern plains, winter season annual Chrysanthemums are sown during September–October. The seeds are sown in nursery beds, earthen pots, seed pans or wooden seed trays. The seed compost should consist of one part each of garden soil, coarse sand, farmyard manure and leaf-mould. For preparing the nursery beds, the soil should be dug up thoroughly and sufficient farmyard manure, should be mixed in soil. Raised nursery beds of convenient size (normally 60cm wide and 15cm high) should be prepared. If soil is heavy, some quantity of sand may be added. It is better if the soil of nursery bed or earthen pots is sterilized with 2% formalin. For this, soil is drenched with formalin solution and is covered with polythene sheet for 45hr. Afterwards, the polythene is removed and soil is dried before sowing the seeds.

In India marigold is one of the most commonly grown flowers and used extensively on religious and social functions in different forms. Because of their ease in cultivation, wide adaptability to varying soil and climatic conditions, long duration of flowering and attractively coloured flowers of excellent keeping quality, the marigolds have become one of the most popular flowers in our country. Flowers are sold in the market as loose or as garlands. Due to its variable height and colour marigold is especially use for decoration and included in landscape plans.

Potato has special seed production problems as the quality characteristics of seed potatoes are influenced by a number of factors and important amongst them are the diseases and pests namely, viruses, fungi, bacteria and nematodes. Once the seed tuber is infected the pathogens, specially viruses, permeate through the plant system. The plant growth, therefore declines and the yield reduces progressively. It is therefore, important that seed stocks should not only be genetically pure but also should be in right physiological condition and disease free at the time of planting. Seed production technology developed for seed potato production, thus aims at producing disease free, genetically pure seed. There are now two independent channels of seed production for hills and plains.

Hill seed : The seed produced in hills (2500 metres above sea level) at suitable locations is called ‘Hill Seed’.

Plain seed : The seed produced in plains at suitable locations is called ‘plain seed’. Northern plains have emerged as an important source of potato seed production. The low aphid, plains seed is in right physiological condition at the planting time and yields higher than the traditional hill grown seed.

Once healthy seed potatoes are introduced into the system of growing them during low Aphid period accompanied by a systematic insecticide application, roguing and removal of haulms before the aphids attain critical number and the re growth is checked, the health standards for the seed crop could be maintained for a number of generations. This system of seed potato production has been designated as ‘Seed Plot Technique’.

Botany: French bean has tap root system with poor nodule formation. Leaves are trifoliate. Though a self-pollinated crop, French bean offers wide variability for plant growth (bushy / climbing), colour of pod (green / waxy coloured), cross section of pod (flat / oval / round), pliability (stringed / string less) etc.

Varieties

1. Arkakomal: Plant is bushy. 70 days for flowering.
2. Blue pod medium: It is a white seed variety. It has bluish black spots on pods.
3. Bountiful: Introduction from US comes up in September to February. Seeds are Brown sweetish. It is resistant to common disease.
4. Contender: Tolerant to powdery mildew and mosaic.
5. Pant anupama: Developed from pantnagar. Bushytype
6. Pusaparvathi: Developed by X ray radiation of American variety IARI