PAWAN NAGAR M.Sc. (Horti.) Fruit science REG. NO : 04-2690-2015 SUBMITTED BY Course No : FSC-506 Course Title : Breeding of Fruit crops
BREEDING OF COCONUT
The coconut palm ( cocos nucifera L.) is a member of the palm family Arecaceae and the only species in the genus Cocos. The English name coconut, comes from the Spanish and Portuguese word coco, which means “monkey face”. Nucifera means “nut bearing”. It is a perennial tree crop widely cultivated in the humid tropics occuring in coastal areas between the latitudes 26°N and 26° S of the equator and at altitudes up to 1200 m. INTRODUCTION
It belong to the lower group of flowering plants called Monocotyledons. The coconut is a large palm, growing to 30 m tall, with pinnate leaves 4-6 m long, pinnae 60-90 cm long; old leaves break away cleanly leaving the trunk smooth. The palm, eulogized as “Kalpavriksha”, “Tree of heaven”, “Tree of life” or “Nature’s supermarket”, is considered as nature’s valuable gift to the mankind due to its innumerable uses to millions of people. The coconut palm is grown throughout the tropical world for decoration as well as for its many culinary and non-culinary uses.
Kingdom: Palm Class: Liliopsida Subclass: Arecidae Order : Arecales Family: Arecaceae Genus: Cocos L. Specimen: Cocos nucifera L. Taxonomic Classification
The origin of coconut is a matter of controversy. There are several views on the place of origin and evidences are also shown to prove the various versions on the origin. Most of the authorities claim it to be a native to south Asia. Recently Gunn et al. (2011) proposed two geographical origins of coconut cultivation such as island South east Asia and southern margins of the Indian subcontinent. ORIGIN AND DISTRIBUTION
The characteristics of the wild coconut fruit particularly the trait such as high content of husk and low proportion of shell, kernel and nut water made the whole nut light, highly water resistant and enabled its dispersal to different continents and countries through marine currents. The coconut palm is grown in the tropical region between latitudes 26°N and 26°S Though it is a sea-side plant, it is grows in interior areas also, far away from the sea.
The main coconut growing areas are located in Asia, Oceania, West Indies, Central and South America and West and East Africa. In India, the coconut palm is grown in an area of around 1.935 million hectares. Kerala, Tamil Nadu and Karnataka account for about 88% of the area, while Andhra Pradesh, Orissa, West Bengal, Maharashtra, Goa, Diu and Daman Assam, Pondicherry, Tripura, Andaman and Nicobar Islands and Lakshadweep account for the remaining 12% of the coconut growing area in the country.
Coconut has been classified into ‘Dwarf’ and ‘Tall’ varieties based on tree habit. The ‘Tall’ coconuts are grow faster than ‘Dwarfs’. Many Tall are grown for the production of copra for oil extraction and coir for fiber; while actively cultivated, these varieties lack the obvious domestication traits of the self pollinating Dwarfs. VARIETAL CLASSIFICATION
The widely accepted classification groups cultivars into two groups – Tall and Dwarfs on the basis of a few important characters like stature , growth characteristics of the palm, precious nature in flowering and nut and copra characters.
Sometimes referred to as var. typica (Nar.) Tall palm are widely planted both for household and commercial use and grow to a height of 20-30m. They are slow maturing and flower 6-10 years after planting, long lived with economic life if about 60-70 years. They are normally cross-pollinating and therefore, considered to be heterozygous. Tall varieties are produce copra of good quantity and quality, and have fairly high oil content as compared to dwarf cultivar. The Tall cultivars commonly grown in India are the West Coast Tall(WCT), Tiptur Tall (TPT), and East Coast Tall (ECT). TALL PALMS
They are sometimes referred to as var. nana (Griff). These are believed to be mutants from tall types with short stature, 8-10 m when 20 years old. They begin bearing about the third year at less than 1 meter height. They have a short productive life of 30-40 years. They are normally self-pollinating and therefore, considered to be homozygous. The nuts are smaller and copra soft, leathery and low in oil content. It generally grown for tender nut and hybrid production. The common Dwarfs available in India are Chowghat Orange Dwarf (COD), Chowghat Green Dwarf (CGD), Kenthali (KTOD) and Gangabondam (GBGD). DWARF PALM
SR.NO NAME AGENCY 1 Chandrakalpa CPCRI 2 Kerachandra CPCRI 3 Chowghat orange dwarf CPCRI 4 Kalpa Pratibha CPCRI 5 Kalpa Mitra CPCRI 6 Kalpa dhenu CPCRI 7 Kalpatharu CPCRI and TNAU 8 Kalpa raksha CPCRI 9 Kalpasree CPCRI 10 Pratap KKV, DAPOLI Coconut varieties released in India
CPCRI : Central Plantation Crops Research Institute TNAU : Tamil Nadu agricultural university. KKV : Konkan Krishi Vidhyapeeth (MH). AAU : Assam Agricultural University KKU : Kerala Agricultural University BCKVV : Bidhan Chandra Krishi Viswavidhyalaya (WB) DBSKKV : Dr. BALASAHEB SAWANT KONKAN KRISHI VIDHYAPEETH (MH) ANGRAU : Acharya N G Ranga Agricultural University. (AP) IGKV : Indira Gandhi Krishi Viswavidyalaya (Chhattisgarh) ABBREVIATION
Coconut is monoecious plant with numerous male and female flowers on each spadix which borne in the axil of each leaf of a bearing palm. Flowering start at 6-12 years of age. Inflorescence length is about 1-2 m with central axis and about 40 laterals branches called spikelets . Each spikelets bear 200-300 male flowers at the top and 1 or 2 female flowers at the base. There are six stamens in male flower, female flowers are 2-3 cm in diameter having a large ovary with three locules and a stigma with three nectary glands. FLORAL BIOLOGY AND POLLINATION
In tall variety female flowers do not become receptive until all male flowers in same spadix have shed their pollens. In dwarf and hybrid varieties interval between two phases i.e. pollen dehiscence and stigma receptivity are less thereby increasing the chances of self pollination. Due to the fact that maturation of inflorescence is a progressive process, pollen discharge and anthesis is continued for about 18-20 days. Generally, dwarf palms are considered as autogamous and tall palms as allogamous but hybrids and dwarf types exhibits both the types of pollination.
Pollination in coconut is carried out by wind and insects (bees are major pollinating agent). The fruit consist of exocarp ( outer skin), mesocarp (fibrous layer) and endocarp which is ovoid shell along with 3 ridge and seed (one) situated at calyx with a thin brown testa attached to the edible endosperm.
INTRODUCTION SELECTION HYBRIDIZATION BIOTECHNOLOGICAL TOOL Coconut breeding was started for the first time in the world in 1916, at coconut research station Neleshwar of Kerala. BREEDING METHODS
The different cultivars of coconut from Ceylon, Indo- China, New Guenea, Java, Indonesia, Thailand, Philippines, Fiji, Laccadives etc. were introduced in India by Madras Agriculture Department. The Cochin Department of Agriculture had also introduced cultivars from Malaysia, sea Island, and Philippines and recently cultivars from Solomon Islands, Borneo, Seychelles, Panama, East Africa, West Indies, etc. Important varieties introduced from different countries are Java, New Guenea, Cochinchines, Philippines, Laccadiv Ordinary, Laccadiv Micro and West coast Tall. INTRODUCTION
Mass selection can be used as effective methods in improvement of coconut. In this method superior mother palms are selected. The success of this method depends on the ability of breeder and heritability of traits under consideration. SELECTION
Coconut palm are being selected on the basis of following characters. a)Yield It should be regular bearer. Annual yield should not be less than 80 per palm. Copra content should be about 150g per nut. b) Age of the plant It is advisable to select palm which have reached full bearing stage and giving higher yield for conservatively four years. Selection of very old tree should be avoided. Seed nut should be collected from established seed garden SELECTION OF MOTHER PALM
c) Nature and disposition of leaves A mother palm should have at least 30 fully opened leaves on the crown. The leaves should have short and strong petiole with wide leaf base firmly attached to the stem. Tree having a drooping or upright position of leaves are generally avoided due to their poor yielding capacity. Female flower distribution per spike determines the yield potential of tree. Generally every leaf axil should be one inflorescence with several spike. There should be 12 bunches on the crown.
d) Size and shape of nut Size is variable factor and which varies from variety to variety . Generally, these shapes are common in coconut i.e. oblong, round and elliptical. Vigour of seedlings depend upon the size of the husked nut, thickness of kernel and size of embryo present in kernel. Palm producing barren nuts, irregular bearing should be avoided for selection as mother palm.
Process of identifying male transmitters can be speeded up by the use of dwarf palm as female since they are largely self pollinated and are reasonably homogenous. The following cross combination have been attempted in coconut: Dwarf × Dwarf Tall × Dwarf Dwarf × Tall Tall × Tall HYBRIDIZATION
Dwarf × Dwarf The crosses between D×D have not given satisfactory results with respect to yield potential traits. Tall × Dwarf (T×D) The hybrid possess desirable traits such as precocity in bearing, higher productivity than the parents. The important dwarf variety used as male parents are Dwarf Orange, Dwarf Green, Gangabondam and Malayan Dwarf yellow. It is reported that all the hybrid of Tall × Dwarf green, Tall × Dwarf orange and Tall × Gangabondam exhibited heterosis in the weight of nut, kernal content and nut water.
Among the male parents Dwarf Orange and Gangabondam proved to be the best for production of economic hybrids with West Coast Tall. In comparative trails involving West Coast Tall and LO as female parents and COD and Gangabondam as male parents the superior performance of LO × COD and CO × GB. COD and Gangabondam are the desirable pollen parents and WCT and LO are desirable female parents.
Dwarf × Tall These hybrids have been found to be of higher production potential than T×D hybrids. The COD × WCT hybrids was found to have better nutrient utilization ability and responded well to lower levels of applied fertilizers Example : Chandra Sankara (COD × WCT). Tall × Tall The poor yield in tall combination may be due to the poor combining ability of other parents. Thus emphasis need to select promising tall parents based on combining ability traits.
Embryo Culture and Tissue Culture Embryo culture has become an important tool for safe germplasm exchange as it reduce the cost of transportation and would meet the phytosanitory regulations. It is useful for producing plantlets from special coconut types such as Mohacha Naral, Thairu thengai etc. where the endosperm is soft and jelly like and does not germinate under normal conditions. Development of tissue culture techniques aimed at rapid multiplication of elite planting material can greatly save time, space, and resources. BIOTECHNOLOGICAL TOOL
Molecular Biology DNA based markers possess the significantly increase the efficiency of coconut breeding programmes. Various molecular markers viz, RAPD, RFLP and SSR used for studying the genetic diversity in coconut germplasm. At presently, work on characterization of conserved coconut germplasm through SSR analysis, work on identification if markers associated with economically important traits as well as with dwarfness and for selection of hybrid seedling in the nursery are in progress.
Linkage Mapping and QTL Identifiction The first genome map for coconut was developed for an East African Tall × Laguna Tall F1 population based on ISTR markers. Three hundred and eighty two markers have been placed in the map resulting in 16 linkage groups and leading to the identification of six QTLs for early germination. Genetic correlation have been established between early germination and early floering, and early germination and high yield. Thus, this has become the first report of the opportunity for marker assisted selection in coconut.
Generation of new mapping populations including coconut root (wilt) phytoplasma-resistant material is being focused in india.
Coconut germinating on Black Sand Beach , Island of Hawaii
Amazing Coconut Tree In Hawaii: Spirals, Trunk,
Development of superior varieties for high yield, tender nut quality, and inflorescence sap (neera) etc. Development of short statured varieties to overcome the shortage of experienced climbers in many parts of country. Application of molecular markers to aid in breeding programmes aiming for biotic and abiotic stresses and identification of hybrid seedling in coconut nurseries. FUTURE THRUST
Shukla Anil kumar, Shukla Arun Kumar, Vasishtha B.B., Fruit Breeding Approaches and Achievements. Shingh H.P., Thomas George V., Krishnakumar V., palms. www.pinterest.com REFERENCES