Mango is one of the world’s most important fruit crops and is widely grown in the tropics and subtropics. Despite its importance in local economies and as an increasingly important export crop, very little progress has been made in terms of classical breeding and genetics that would facilitate mango cultivar improvement. Consequently, almost all the important mango cultivars in its area of origin in India and Southeast Asia are clonal selections that are several hundred years old. Biotechnology has the potential to revolutionize mango improvement, germplasm storage and production. Genetic transformation of embryogenic cultures opens the possibility of improving existing cultivars by incorporating into their genomes genes that target specific traits. Embryogenic mango cultures have the potential to rationalize germplasm storage and the international exchange of disease-indexed clonal materials. Finally, the development of efficient in vitro vegetative reproduction systems, whether this is based upon production of embryogenic or shoot tip and nodal cultures, could enable the availability of clonal rootstocks of exotic monoembryonic selections.

Trees have a distinctive and generally long juvenile period during which vegetative growth rate is rapid and floral organs do not differentiate. Among trees, the juvenile period can range from 1 year to 15–20 years, although with some forest tree species, it can be longer. Vegetative propagation of trees is usually much easier during the juvenile phase than with mature phase materials. Therefore, reversal of maturity is often necessary in order to obtain materials in which rooting ability has been restored. Micrografting has been developed for trees to address reinvigoration/rejuvenation of elite selections to facilitate vegetative propagation. Generally, shoots obtained after serial grafting have increased rooting competence and develop juvenile traits; in some cases, graft-derived shoots show enhanced in vitro proliferation. Recent advances in graft signaling have shown that several factors, e.g., plant hormones, proteins, and different types of RNA, could be responsible for changes in the scion. The focus of this review includes (1) a discussion of the differences between the juvenile and mature growth phases in trees, (2) successful restoration of juvenile traits through micrografting, and (3) the nature of the different signals passing through the graft union.

Abstract This chapter discusses the botany and history, importance, breeding and genetics, molecular genetics, gene cloning, genomics, micropropagation, somatic cell genetics, genetic manipulation, genetic transformation, somatic hybridization and cryopreservation of longan and lychee.

This chapter focuses on the origin, morphological and physiological characteristics, cultivation history, breeding, vegetative propagation methods, cryopreservation of embryos and molecular genetics of mangoes (Mangifera indica). The importance of genetic manipulation in improving the fruit quality, eliminating physiological disorders of certain selections (internal breakdown of fruit), altering tree architecture and increasing resistance to insect pests and diseases is also discussed.

<title>Abstract</title> This book covers the biotechnology of all the major perennial fruit and nut species, including <italic>Actinidia</italic> spp., <italic>Anacardium occidentale</italic>, <italic>Mangifera indica</italic>, <italic>Pistacia vera</italic>, <italic>Annona</italic> spp., <italic>Cocos nucifera</italic>, <italic>Elaeis guineensis</italic>, <italic>Phoenix dactylifera</italic>, <italic>Ananas comosus</italic>, <italic>Carica papaya</italic>, <italic>Garcinia mangostana</italic>, <italic>Diospyros kaki</italic>, <italic>Vaccinium</italic> spp., <italic>Castanea</italic> spp., <italic>Carya illinoinensis</italic>, <italic>Juglans regia</italic>, <italic>Persea americana</italic>, <italic>Theobroma cacao</italic>, <italic>Musa</italic> spp., <italic>Psidium guajava</italic>, <italic>Olea europaea</italic>, <italic>Averrhoa carambola</italic>, <italic>Passiflora</italic> spp., <italic>Eriobotrya japonica</italic>, <italic>Fragaria</italic> × <italic>ananassa</italic>, <italic>Malus</italic> × <italic>domestica</italic>, <italic>Prunus persica</italic>, <italic>Prunus armeniaca</italic>, <italic>Prunus domestica</italic>, <italic>Prunus</italic> spp., <italic>Prunus dulcis</italic>, <italic>Pyrus</italic> spp., <italic>Cydonia</italic> spp., <italic>Rubus</italic> spp., <italic>Citrus</italic> spp., <italic>Dimocarpus longan</italic>, <italic>Litchi chinensis</italic>, and <italic>Vitis</italic> spp. This book also covers biotechnologies and also traditional ones, such as regeneration pathways, protoplast culture, <italic>in vitro</italic> mutagenesis, and ploidy manipulation that have been applied to many of these species. The species are organized by plant family to facilitate comparisons among related ones. Each species is discussed in relation to its family and its related wild forms, and most are accompanied by full colour illustrations. This book is a vital resource for those working on the improvement of perennial fruit, nut and plantation crops.

Abstract This chapter focuses on the origin, geographical distribution, morphological and phenological characteristics, cultivation history, breeding, vegetative propagation methods and molecular genetics and genomics of avocados (Persea americana). The importance of developing various genetic manipulation methods for the genetic improvement of avocado germplasm is also discussed.

Papaya (Carica papaya L) is an important tropical fruit crop. The fruit is consumed fresh and used in the pharmaceutical, rayon and food industries. Papaya improvement for stress tolerance and qualitative traits using conventional breeding has been difficult due to the narrow germplasm pool in the Carica genus and sexual incompatibility problems encountered during intergeneric hybridization with other genera in the Caricaceae family. Genetic engineering is an important tool in papaya improvement for modifying one or more traits in elite cultivars without altering existing characteristics. Advances in genetic engineering have been facilitated by concerted efforts for genome sequencing of papaya, development of papaya regeneration systems and efficient gene insertion techniques for transfer of desirable traits.Papaya regeneration via organogenesis and somatic embryogenesis has been refined during the past 3 decades. Early efforts to optimize gene insertion protocols utilized a number of reporter and selectable marker genes, viral- and bacterial-derived regulatory sequences and functional genes for biotic and abiotic stress tolerance. Transgenic plants were routinely produced with several cultivars. One of the best success stories in the commercialization of a genetically modified fruit crop has involved the development of transgenic papaya ring spot virus (PRSV) resistant Rainbow and SunUp cultivars, which saved the Hawaiian papaya industry. Additionally, genetically modified papayas with traits for disease resistance and extended shelf life have been extensively screened in field tests.The papaya genome sequence was published in 2008 and has opened new avenues for papaya improvement by precision breeding, which involves the use of regulatory and functional gene sequences from related genera of the Caricaceae family, and is a logical extension of conventional breeding and genetic transformation. The application of precision breeding technology for papaya can pave the way for the development of consumer and eco-friendly cultivars that would be developed in ways similar to conventional breeding while causing fewer GMO-related concerns. (C) 2016 Elsevier Ltd. All rights reserved.

In order to address the need for production of parthenocarpic fruits, embryogenic cultures of 'Brewster' ('Chen Tze') litchi derived from leaves of a mature tree were transformed with the PISTILLATA (PI) cDNA in antisense orientation through Agrobacterium-mediated transformation. In four independently transformed lines, transgene integration was confirmed by conventional and quantitative PCR. The four transgenic lines differed with respect to the relative copy number of the transgene and expression levels, and there was no correlation between the two traits. The expression of the litchi PI homolog was detected in transformed and non-transformed embryogenic cultures. Although expression levels were low overall, they were significantly higher in wild-type plants compared to lines that were transformed. This result suggests that post-transcriptional silencing of the litchi PI homolog induced by an antisense oriented transgene could be a successful strategy; however, silencing in floral primordia to produce parthenocarpic fruits can only be confirmed in mature plants after several years.

Embryogenic yam (Dioscorea rotundata) cultures were induced from petioles of leaves of in vitro grown plants on medium supplemented with different 2.4-D concentrations. Cultures were maintained either on semisolid or in liquid MS medium supplemented with 4.52 μM 2.4-D. The effect of sucrose concentration on somatic embryo development was also evaluated and the effects of different BAP concentrations on somatic embryo conversion were determined. Treatments were distributed using a complete randomized design. The highest rate of induction occurred with 4.52 μM 2.4-D. Sucrose at 131.46 mM significantly enhanced somatic embryo development. The conversion rate was not affected by BAP.

1. Botany and Importance S K Mukherjee (deceased) and R E Litz 2. Taxonomy and Systematics J M Bompard 3. Important Mango Cultivars and Their Descriptors R J Knight, Jr., R J Campbell and I Maguire 4. Breeding and Genetics C P A Iyer and R J Schnell 5. Reproductive Physiology T L Davenport 6. Ecophysiology B Schaffer, L Urban, P Lu and A W Whiley 7. Fruit Diseases D Prusky, I Kobiler, I Miyara and N Alkan 8. Foliar, Floral and Soilborne Diseases R C Ploetz and S Freeman 9. Physiological Disorders V Galan Sauco 10. Pests J E Pena, M Aluja and M Wysoki 11. Crop Production: Propagation S Ram (deceased) and R E Litz 12. Crop Production: Mineral Nutrition I S E Bally 13. Crop Production: Management J H Crane, S Salazar-Garcia, T-S Lin, A C de Queiroz Pinto and Z-H Shu 14. Postharvest Physiology J K Brecht and E M Yahia 15. Postharvest Technology and Quarantine Treatments G I Johnson and 16. P J Hofman 17. World Mango Trade and the Economics of Mango Production E A Evans and O J Mendoza 18. Fruit Processing L C Raymundo, M T Ombico and T M de Villa 19. Biotechnology R E Litz, M A Gomez Lim and U Lavi.

Cryopreservation of embryogenic cultures induced from leaves of mature phase trees of Litchi chinensis Sonn. was performed following a vitrification method. Vitrification solution (PVS2) was utilized at two temperatures: 0 degree C and 25 degree C. Post-treatment survival percentages and regrowth rates of the cultures were higher when the PVS2 solution was at 0 degree C. All samples cryopreserved with PVS2 at 0 degree C survived; their regrowth rate after eight weeks on semi-solid maintenance medium was the same as non-treated controls. Cryopreservation suppressed somatic embryo development; the number of somatic embryos derived from cryopreserved cultures was less than the number obtained from the controls. Desiccation during the PVS2 treatment had no effect on reversal of hyperhydric embryogenic cultures.

This chapter discusses the current state of mango cell culture, gene cloning, and manipulation of cell cultures to address plant breeding objectives by genetic engineering. Specific topics that are covered consisted of: cell and tissue culture (organogenesis, somatic embryogenesis, and protoplast isolation and culture), molecular breeding and genetics (marker-assisted selection, gene cloning and genomics), genetic engineering (in vitro induced mutations and genetic transformation), and in vitro conservation (medium-term storage and long-term storage).

Resumen es: A partir de explantes de embriones cigoticos y megagametofi- tos fueron inducidos cultivos organogenicos de Dioon merolae del estado de Chiapas (Mexico...

Organogenic cultures were induced from zygotic embryo and megagametophyte explants of the Chiapas State (Mexico) endangered cycad species, Dioon merolae. The Litz induction medium consisted of B5 major salts, MS medium minor salts and the organics glutamine (400mg.l(-1)), arginine (100mg.l(-1)), asparagines (100mg.l(-1)), sucrose (60g.l(-1)), gellan gum (4g), and supplemented with 0, 0.45, 2.26, 4.52 and 9.05 mu M 2,4-dichlorophenoxyacetic acid (2,4-D) and 0, 2.32, 4.60, 9.30, 13.90 mu M kinetin (K), arranged as a 5x5 factorial in a randomized block design. Cultures were maintained in darkness at 25 degrees C, and callus was subcultured onto fresh medium at 4 week intervals. Callus initiation occurred on a wide range of plant growth regulators (PGR) combinations from megagametophyte explants. In comparison, callus initiation from explanted zygotic embryos occurred on few PGR combinations. Adventitious shoot induction occurred from callus oil formulations with K and 2,4-D. Through the histological analysis of longitudinal sections of zygotic embryos were detected apical meristematic cells of the shoot and root and in megagametophytes the formation of elements similar to tracheids and coralloid roots. This technique has a great potential for preservation of the highly endangered cycads.

It has been possible to regenerate a few cycad species in vitro by somatic embryogenesis, either from zygotic embryos ( Ceratozamia hildae, C. mexicana, Encephalartos cycadifolius , E. dyerianus, E. natalensis, Zamia fischeri, Z. furfuracea , and Z. pumila ) or from leaves of mature phase trees ( C. euryphyllidia, Ceratozamia hildae , and C. mexicana ). This strategy has great potential for the commercial vegetative propagation of certain highly endangered species (e.g., C. euryphyllidia ) and should indirectly protect wild populations of these species by discouraging collection in situ. Embryogenic cultures of several cycad species have grown vigorously and are highly morphogenic more than 11 years after induction. The long-term conservation of cycad genetic resources can also be addressed for species that can be regenerated by somatic embryogenesis. Preliminary studies indicate that embryogenic cultures that have been pretreated on plant growth medium containing 0.75 M sucrose for two days, encapsulated in sodium alginate, and desiccated for six hours can survive immersion in liquid nitrogen (−196°C).