Biotechnology of Fruit and Nut Crops

Richard E Litz, Fernando Pliego-Alfaro, Jose Ignacio Hormaza, Richard Litz, Fernando Pliego-Alfaro, Jose Ignacio Hormaza

• Publisher: CAB International
• Year: 2020
• Print ISBN: 9781780648279
• eBook ISBN: 9781780648293
• Edition: 2
• Topic: Biological Sciences
• Subtopic: Biotechnology
• Index: Biological Sciences

This book covers the biotechnology of all the major perennial fruit and nut species. Since the publication of the first edition of this book in 2005, there has been significant progress in cell culture, genomics and genetic transformation for many of these species. This book covers these biotechnologies and also traditional ones, such as regeneration pathways, protoplast culture, in vitro mutagenesis, and ploidy manipulation that have been applied to many of these species. Three species, Diospyros kaki (persimmon), Punica granatum (pomegranate) and Eriobotrya japonica (loquat) are included for the first time, and several Prunus species now receive separate coverage. 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.The book features: Detailed coverage of major perennial fruit and crop species.Coverage of traditional and new biotechnologies.Full colour illustrations to aid identificationThis book is an essential resource for scientists and postgraduate students who are engaged in the improvement of perennial fruit, nut and plantation crops and will also be an important accession for university and agricultural research libraries.

1 Actinidiaceae

1.1 Actinidia spp. Kiwifruit

Manuel Rey,^1,2 Yolanda Ferradás,^3,4 Óscar Martínez¹ and María Victoria González³

¹Departamento Biología Vegetal y Ciencia del Suelo, Facultad de Biología, Campus Universitario, Universidad de Vigo, Vigo, Spain; ²CITACA, Agri-Food Research and Transfer Cluster, Campus da Auga, Universidad de Vigo, Ourense, Spain; ³Departamento Biología Funcional, Facultad de Farmacia, Universidad de Santiago de Compostela, Campus Sur, Santiago de Compostela, Spain; ⁴Present address: Instituto de las Ciencias de la Vid y del Vino (Gobierno de La Rioja-Consejo Superior de Investigaciones Científicas-Universidad de La Rioja), Logroño, Spain

1. Introduction

1.1. Botany and history

The genus Actinidia, commonly known as kiwifruit, is included in the Actinidiaceae family together with Clematoclethra (Franch.) Maxim. and Saurauia [Saurauja] Willdenow. This genus comprises c.54 species and 75 taxa (Wang and Gleave, 2012; Huang et al., 2013). Paleobiology studies have shown that Actinidia is at least 20–26 million years old (Qian and Yu, 1991). Actinidia plants are perennial, deciduous, climbing and/or scrambling vines. They are often reticulate polyploids with a basic chromosome number of x = 29 (McNeilage and Considine, 1989). The genus is unusual for the extensive variation in ploidy, meaning that diploid, tetraploid, hexaploid and even octoploid individuals can be found (Ferguson and Huang, 2007). All Actinidia species appear to be dioecious, which means that a single genetic determinant controls sex with a unique set of X/Y chromosomes together with a sex-neutral (XX)_n chromosome set, where n depends on the ploidy levels (McNeilage, 1997; Testolin et al., 1999; Fraser et al., 2009). Sometimes gender-inconstant variants can occur as well; in this case, staminate flowers usually are smaller than pistillate flowers (McNeilage, 1991a,b). Flowers are usually arranged in cymes, although they sometimes can appear solitary. Identity of floral organs is determined by the (A)BCE-like floral model, where the A function is unclear (Varkonyi-Gasic et al., 2011). The staminate flowers in male vines develop viable pollen and a rudimentary ovary without ovules. On the other hand, the pistillate flowers in female vines bear a functional ovary, which is formed by the fusion of many carpels, leaving the radiating styles free. The stamens release sterile pollen because viability is lost by programmed cell death (PCD) during microspore development (Coimbra et al., 2004; Falasca et al., 2013).

Floral evocation occurs during one growth season while floral initiation occurs in the following season (Walton et al., 1997). During the reproductive process, pollen dispersion takes place by wind and, mainly, bees (Costa et al., 1993). Some Actinidia species are characterized by a high reproductive success, being able to produce one fruit per flower (Biasi and Costa, 1984). Abundant secretions released into the intermembrane space throughout the pistil by transmitting tissue cells are involved in pollen nutrition and guidance, disappearing after pollen tube passage (González et al., 1996). Despite its reproductive success, kiwifruit has a short effective pollination period which is limited by the stigmatic receptivity relying on stigmatic papillar integrity (González et al., 1995a,b). This short effective pollination period seems to be due to PCD processes occurring in the secretory tissue, which are eventually accelerated by pollination (Ferradás et al., 2014).

Actinidia fruits are defined as berries, with great diversity in size, shape, hairiness, skin toughness and palatability, external and internal colour, flavour, flesh chemical composition and storage capacity (Ferguson and Huang, 2007). Kiwifruits have a high nutritional value and are an excellent source of vitamins C and E, folate and potassium, with high antioxidant capacity (Wang et al., 1996; Ferguson and Ferguson, 2003; Drummond, 2013).

Actinidia chinensis is the most important crop species of the genus, although Actinidia arguta, Actinidia kolomikta or Actinidia eriantha also have some importance (Ferguson and Huang, 2007). Planchon (1847) described kiwifruit as a unique species. Further studies revealed differences in the level of ploidy and in morphological characteristics among individuals (Liang, 1975; Liang and Ferguson, 1984), and two separate species were recognized, A. chinensis and Actinidia deliciosa, with diploid and hexaploid individuals, respectively (Liang and Ferguson, 1984). Currently, they are recognized as two varieties of the same species, A. chinensis var. chinensis and A. chinensis var. deliciosa, due to the presence of clines between both varieties, as well as extensive introgressive hybridization where they cohabit (reviewed in Ferguson, 2016).

The Actinidia genus is distributed throughout much of eastern Asia, with most species and intraspecific taxa occurring in south central China (Liang, 1983). In 1904, some seeds of A. chinensis were introduced into New Zealand (Ferguson, 2004), with the establishment of the first commercial plantation in the 1930s (Ferguson and Stanley, 2003; Ferguson and Huang, 2007). New Zealand was responsible for the domestication and commercialization of kiwifruit. The inherent organoleptic, nutritional and storage qualities make kiwifruit a widely accepted and popular fruit crop for producers and consumers. For these reasons, commercial kiwifruit growing areas have expanded rapidly in recent decades. In 2017, the global kiwifruit growing areas had reached over 247,794 ha, with China (165,728 ha), Italy (26,403 ha), New Zealand (11,705 ha) and Iran (10,771 ha) as the main producers accounting for about 87% of world kiwifruit plantings; global kiwifruit production represents 0.62% of total production for major fruit crops (FAOSTAT, 2014). A. chinensis var. deliciosa is the most commercialized kiwifruit, and female ‘Hayward’ is the main cultivar (Ferguson, 1999). However, different species and varieties have been increasing in importance in the last few years.

1.2. Breeding and genetics

Actinidia is a genus of recent domestication. Initially, the kiwifruit industry was based on cultivars of A. chinensis var. deliciosa, and since 1975, ‘Hayward’ has been the dominant cultivar (Ferguson and Huang, 2007). Another important cultivar is A. chinensis var. chinensis ‘Hort16A’, known commercially as Zespri^® Gold kiwifruit (Wang and Gleave, 2012). The rapid expansion of kiwifruit cultivation has revealed the need to obtain new cultivars or domestication of new species that are better adapted to different growing conditions. A distinctive feature of the genus is the structured reticulate pattern of diploids, tetraploids, hexaploids and octoploids in diminishing frequency, associated with geographic separation of ploidy races (Ferguson and Huang, 2007). This ploidy variation between taxa and the existence of ploidy races within taxa can make crossing in Actinidia difficult. However, Li et al. (2010) observed that the type of fruit hairs, fruit flesh colour and fruit weight are related to ploidy. Therefore, breeders can obtain a large range of kiwifruits.

1.2.1. Rootstocks

Major breeding objectives. Kiwifruit was initially not grafted in commercial orchards, but expansion of the industry to regions with poor soil or environmental features is essential for the future of this crop. Controlling excessive vegetative vigour and improving the percentage of fruit set are important. Italy has been utilizing the clonal rootstock ‘D1’ for calcareous soils (Vizzotto et al., 1999), and ‘Bruno’ and ‘Kaimai’ are important in New Zealand (Oliveira and Fraser, 2005). ‘Bruno’ seedlings have been used to support vines that grow rapidly and with greater productivity (Lawes, 1990). ‘Kaimai’, a clonal rootstock of Actinidia hemsleyana Dunn, stimulates doubling the number of flowers on each shoot of the scion (Wang et al., 1994b).

BREEDING ACCOMPLISHMENTS. Analyses of A. arguta and different rootstock–scion combinations of A. arguta have demonstrated that both rootstock and scion affect actinidin activity and free sugar and organic acid content in fruit (Boyes et al., 1996, 1997). Interspecific rootstocks of Actinidia can have a major effect on the amount of vegetative growth on A. chinensis var. chinensis ‘Hort16A’ vines, dramatically altering plant size, leaf area and scion vigour (Clearwater et al., 2006, 2007). Thorp et al. (2007) reported that interspecific clonal rootstocks had a substantial effect on the accumulation and concentration of inorganic nutrients in the fruit, leaves and stem sap of ‘Hort16A’ vines. The use of rootstocks of other species of Actinidia, e.g. A. hemsleyana, A. eriantha and Actinidia rufa, reduced the level of floral abortion and increased bud burst in ‘Hayward’ (Wang et al., 1994a). The flower-promoting rootstocks have more starch grains, more and larger xylem vessels and idioblasts with raphides and mucilage (Wang et al., 1994b). Powell and Santhanakrishnan (1986) showed that ‘Hayward’ on mycorrhiza-infected rootstocks had increased shoot length and fruit production.

1.2.2. Scions

Major breeding objectives. Fruit size has been an important criterion for selecting wild species from China with commercial potential (Ferguson and Huang, 2007). Kiwifruit could make an important contribution to human health (Singletary, 2012; Skinner et al., 2013); the fruit...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contents
• List of Contributors
• Preface
• 1 Actinidiaceae
• 2 Anacardiaceae
• 3 Annonaceae
• 4 Arecaceae
• 5 Bromeliaceae
• 6 Caricaceae
• 7 Clusiaceae
• 8 Ebenaceae
• 9 Ericaceae
• 10 Fagaceae
• 11 Juglandaceae
• 12 Lauraceae
• 13 Malvaceae
• 14 Musaceae
• 15 Myrtaceae
• 16 Oleaceae
• 17 Oxalidaceae
• 18 Passifloraceae
• 19 Rosaceae
• 20 Rutaceae
• 21 Sapindaceae
• 22 Vitaceae
• Index
• Cabi
• Back