Available online at www.ijpab.com Vinay et al Int. J. Pure App. Biosci. 5 (2): 1168-1181 (2017) ISSN: 2320 – 7051 DOI: http://dx.doi.org/10.18782/2320-7051.2722 ISSN: 2320 – 7051 Int. J. Pure App. Biosci. 5 (2): 1168-1181 (2017) Research Article Recent Advances in Annona Breeding: A Review Vinay, G. M.*, Sakthivel, T. and Priyanka, H. L. Division of Fruit Crops, Indian Institute of Horticultural Science, Hesaraghatta lake Post, Bengaluru-89 *Corresponding Author E-mail: [email protected] Received: 19.03.2017 | Revised: 30.03.2017 | Accepted: 2.04.2017 ABSTRACT The Annonaceae family comprises about 120 genera and more than 2000 species. The genus Annona is the most economically important one, containing 120 species. The opportunity for breeding improvement in the annona is significant and challenging. There is a lot more species are available but certain inherent constraints are involved like: long juvenility, higher levels of heterozygosity and large area requirement for assessment of hybrids. On the other hand, wide range of diversity and ease of vegetative hybrid propagation are the advantages for the breeders. There are very few man made commercially important hybrids. Its development is mostly based on the selection of clones were made for fruit quality only. Requirements of a good cultivar involve: dwarfness, precocity and profuse bearing, attractive, good sized and quality fruit, absence of physiological disorders, disease and pest resistance and improved shelf life etc. Comprehensive knowledge about the phenology and advanced techniques for hybridization have been quite helpful to overcome the problems like poor eating and keeping quality. The development of the genetic markers has further reduced the uncertainty in breeding of annona and maintaining the hybrid populations in a better way. Key words: Annona, Heterozygosity, Breeding, Juvenility. INTRODUCTION significant40 and economically important fruits The Annonaceae family comprises about 120 in several tropical and sub-tropical countries. genera and more than 2000 species. The genus And also some other species are ramphal Annona is the most economically important (Annona reticulata) soursop (Annona one, containing 120 species19. The relatively muricata) and pond apple (Annona glabra). wider adaptability of the trees and a good The sugar apple species name ‘squamosa’ consumer preference for their fruits make the refers to the knobby appearance of the fruit. commercial cultivation of these species Sugar apple is a small tropical tree originating attractive. Among the edible annonas, in the New World tropics, probably Central cherimoya (Annona cherimola Mill.), sugar America. Sugar apple is the mostly grown apple (A. squamosa L.) and the hybrid annona species. between the two, atemoya, are commercially Cite this article: Vinay, G.M., Sakthivel, T. and Priyanka, H.L., Recent Advances in Annona Breeding: A Review, Int. J. Pure App. Biosci. 5(2): 1168-1181 (2017). doi: http://dx.doi.org/10.18782/2320-7051.2722 Copyright © April, 2017; IJPAB 1168 Vinay et al Int. J. Pure App. Biosci. 5 (2): 1168-1181 (2017) ISSN: 2320 – 7051 The fruit is frequently found in village markets spring. The single, protogynous, mild fragrant but has not shown much potential for large flower emerges from the leaf axils, and commercial cultivation due to the small fruit possesses a short peduncle. Flowering occurs size, frequent cracking at maturity and poor once in a year and it starts when the tree is 3 to shelf life. The perishable nature and supply 4 years old. Anthesis starts in the early shortages make marketing localized or air morning and it takes 8h to attain complete shipment essential. Commercial cultivation of opening. The fruit is normally heart-shaped, cherimoya occurs in Chile, Ecuador, conical, oval or somewhat irregular in form Columbia, Australia, Spain and California28, due to irregular pollination. Fruits measure 7.5 However, the cultivation of atemoya is mostly to 12.5 cm in length and weigh from 200 to limited to Australia and Florida12. Another 700 g. The fruit surface is smooth in some allied species bullock’s heart, which possesses varieties; in others, it is covered with small a number of traits that would be desirable in conical protuberances over the carpels. The other edible annonas, is grown on a limited fruit rind is delicate and thin, and is greenish- scale in Australia, Africa, India, Peru and yellow when ripe29. The white, subacid flesh South-East Asia19. has a fragrant, delicate flavor. The fruit has The improvement of annona rather numerous seeds (21 to 41 seeds/fruit), which any crop needs to explore new recombinants are 1.5 to 2.0 cm in length and approximately primarily by means of exploiting the breeding 1.0 cm in width42. methodologies. Diversity or heterogeneity is 2. Sugar apple – Annona squamosa L. the main character desired for breeding either The sugar apple tree is deciduous and much natural or manmade. It is required to have vast smaller than the soursop, reaching a maximum genetic pool to get new combinations of of 6.0 m in height, with many lateral branches. desired nature and developing new hybrids. The stems present lenticels, while the young Breeding has yet to play its role in the shoots are pubescent and the oldest are development of this crop as it has not been smooth. The leaves are oblong-elliptical in effectively manipulated in the distant past. form, measuring 5 to 17 cm in length and 2 to Now, the scientists have developed certain 7 cm in width, with an obtuse or acuminate hybrids of annona. To go for such strategies, a apex35. The flowers measure 2.0 to 2.5 cm in comprehensive knowledge of the different length and are much smaller than soursop annona species, physiology of the reproductive flowers, being similar in size and form to those parts, their breeding behaviour and cytological of cherimoya. Pollen germination is low and information of the crop is needed. This will may influence final fruit set, which varies from eventually help to improve annona production 5.4% to 5.6%51. The fruit is rounded, heart- status. shaped, ovate or conical, 5 to 7.5 cm in Description of the important Annona diameter, 6 to 10 cm in length and weighing species 120 to 330 g. The white, custard-like pulp has 1. Cherimola - Annona cherimola P. Mill. a pleasant sweet-sour flavour. The fruit The name cherimoya derives from the contains 35 to 45 black seeds, each 1.5 to 2.0 Quechua name "chirimuya", which means cm in length and 0.6 to 0.8 cm in width50. "cold seeds"27. It is a small, erect, deciduous 3. Atemoya – Annona atemoya L. tree. It has simple, alternate, leaves are ovate- The tree is highly vigorous, fast-growing, 25 lanceolate to elliptical in shape, 10 to 25 cm to 30 feet tall. The branches typically drooping long, glabrous on the ventral surface and and the lowest touching the ground. The leaves pubescent dorsally, with leaf shedding in the are deciduous, alternate, elliptical, leathery and Copyright © April, 2017; IJPAB 1169 Vinay et al Int. J. Pure App. Biosci. 5 (2): 1168-1181 (2017) ISSN: 2320 – 7051 less hairy than those of the cherimoya. The considered the least tasty of the cultivated flowers are long-stalked, triangular, yellow, 6 annonas. There are commonly more than 40 cm long and 4-5 cm wide15. The fruit is oblong, dark coffee-coloured seeds per fruit. conical or heart-shaped, weighs more than 5. Soursop - Annona muricata L. 1.00kg. The rind is thick and composed of The soursop has an erect growth habit with a fused areoles more prominent and angular than high canopy height-to-diameter ratio, although those of the sugar apple, with tips that are it tends to be low-branching and bushy, with rounded or slightly upturned; firm, pliable, and upturned limbs. It is a small, slender, indehiscent. Pulp is fragrant, snowy-white, evergreen tree, 4 to 8 m tall when fully mature. fine texture, almost solid, not conspicuously The stems are rounded, rough and not divided into segments, with fewer seeds than pubescent, with a dark-brown colour. The the sugar apple; sweet and subacid at the same leaves have short petioles, and are oblong- time and resembling the cherimoya in flavor. ovate to cylindrical, 14 to 16 cm in length and The seeds are cylindrical, dark brown or black 5 to 7 cm in width42. The flowers of soursop in colour13. are much larger than the other species, being 4. Bullock's heart / Ramphal - Annona 3.2 to 3.8 cm in length. The flowers start to reticulata L. open in the early morning and complete The tree reaches 6.0 to 7.5 m in height, with anthesis takes approximately 6h, depending on many lateral branches; stems are cylindrical, the climate. Soursop produces an ovate, with lenticels and very short coffee-coloured conical or heart-shaped fruit, that is dark green hairs. It is considered the most vigorous of the when unripe and a slightly lighter green when annonas. The fruit is considered to be of ripe. The rind has many short, fleshy, pointed inferior quality. It can be distinguished from carpel protuberances and is popularly regarded cherimoya by its long, narrow, glabrous as 'spiny'. The soursop has the largest fruit in leaves, from sugar apple by its solid, compact the genus, weighing from 0.9 to 10 kg, and fruit, as well as its larger leaves, and from A. averaging 4 kg41. The flavour is more acid and glabra by its small, dark brown seeds42. The less sweet .The fruit has 127 to 170 seeds, leaves are oblong-lanceolate and dark-green, scattered throughout the pulp. They are toxic.