Jayanthi Nadarajan

Jayanthi Nadarajan
Plant and Food Research · New Cultivar Innovation

PhD

About

68
Publications
13,181
Reads
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629
Citations
Additional affiliations
May 2017 - present
Plant and Food Research
Position
  • Researcher
October 2016 - present
Rothamsted Research
Position
  • CHAP-National Reference Collection of Biotic Crop Threats
June 2006 - present
Royal Botanic Gardens, Kew
Position
  • Cryobiology Specialist

Publications

Publications (68)
Article
Full-text available
Certain viruses dramatically affect yield and quality of potatoes and have proved difficult to eradicate with current approaches. Here, we describe a reliable and efficient virus eradication method that is high throughput and more efficacious at producing virus-free potato plants than current reported methods. Thermotherapy, chemotherapy, and cryot...
Article
Full-text available
Syzygium maire is a highly threatened Myrtaceae tree species endemic to New Zealand. Due to its recalcitrant seed storage behaviour, cryopreservation is the only viable long-term ex situ conservation option for this species. This study investigated viability, oxidative stress, thermal properties, and ultrastructure of zygotic embryo axes (EAs) desi...
Conference Paper
Many orchid species are included on threatened species lists because they are vulnerable to habitat degradation and climate change. However, a basic understanding of orchid seed biology to support conservation efforts is still lacking for the majority of species in this large family. Greater knowledge of orchid seed characteristics would provide us...
Article
• Changes in seed lipid composition during ageing are associated with seed viability loss in many plant species. However, due to their small seed size, this has not been previously explored in orchids. We characterized and compared the seed viability and fatty acid profiles of five orchid species before and after ageing: one tropical epiphytic orch...
Presentation
Full-text available
Potato is mainly propagated via tubers, therefore, viral diseases are a major constraint for cultivation. At least 50 viruses are known to infect cultivated potatoes, but only a few cause major crop losses globally. Potato virus M (PVM), Potato virus A (PVA), and Potato virus S (PVS) are among the most widespread and significant viral pathogens res...
Article
Background: Syzygium maire is a threatened tree species with limited information on long-term storage options for its recalcitrant seed. Objective: To evaluate the cryopreservation of S. maire zygotic embryo axes (EA) using dehydration, encapsulation-dehydration as well as PVS2 vitrification using droplet vitrification (DV) and the novel droplet...
Article
All seeds eventually die even under optimal storage conditions. The moment of viability loss is difficult to predict and detect. In order to differentiate between dead and viable dormant orthodox seeds, GC-MS analysis was used to non-invasively evaluate the volatile signature of seeds of Pyrus communis L. and Sorbus aucuparia L. Dormant seeds are c...
Article
Full-text available
Ex situ conservation of orchid seeds requires the application of modern biotechnology to determine seed quality and to optimise in vitro regeneration. The nutrient requirements for germination and seedling growth in vitro can be species-specific and influenced by life history traits and habitats. Therefore, this study aimed to explore in vitro seed...
Article
Syzygium maire is an endemic tree in New Zealand and classified as critically endangered. The in situ populations of this species are further threatened by the incursion of myrtle rust. The biology and ecology of S. maire have not been well documented and limited information on seed development, effective germination and seed storage behaviour of S...
Article
Full-text available
The current threat of myrtle rust (Austropuccinia psidii) to New Zealand Myrtaceae, including a number of indigenous and socio-economically important species, requires that ex situ conservation is used to complement in situ populations. New Zealand’s Myrtaceae have received little attention in terms of ex situ conservation. In this study, we assess...
Article
The current threat of myrtle rust (Austropuccinia psidii) to New Zealand Myrtaceae, including a number of indigenous and socio-economically important species, requires that ex situ conservation is used to complement in situ populations. New Zealand’s Myrtaceae have received little attention in terms of ex situ conservation. In this study, we assess...
Article
Full-text available
Seed morphology underpins many critical biological and ecological processes, such as seed dormancy and germination, dispersal, and persistence. It is also a valuable taxonomic trait that can provide information about plant evolution and adaptations to different ecological niches. This study characterised and compared various seed morphological trai...
Article
Full-text available
Resistance to the pandemic strain of Austropuccinia psidii was identified in New Zealand provenance Leptospermum scoparium, Kunzea robusta,and K. linearis plants. Only 1 Metrosideros excelsa-resistant plant was found (of the 570 tested) and no resistant plants of either Lophomyrtus bullata or L. obcordata were found. Three types of resistance were...
Article
Full-text available
Resistance to the pandemic strain of Austropuccinia psidii was identified in New Zealand provenance Leptospermum scoparium, Kunzea robusta, and K. linearis plants. Only 1 Metrosideros excelsa-resistant plant was found (of the 570 tested) and no resistant plants of either Lophomyrtus bullata or L. obcordata were found. Three types of resistance were...
Chapter
Synthetic seed (synseed) describes artificially encapsulated plant tissues, usually somatic embryos but also other vegetative parts that can be propagated into complete plants under in vivo or in vitro conditions. Synseed technology can be utilised for medium-term storage and long-term conservation of valuable ornamental plant germplasm. Synseeds c...
Poster
Full-text available
Seed dormancy in Actinidia species (kiwifruit seed)
Article
Full-text available
Thermal fingerprints for seeds of 20 crop wild relatives of Brassicaceae stored for 8 to 44 years at the Plant Germplasm Bank-Universidad Politécnica de Madrid and the Royal Botanic Gardens, Kew's Millennium Seed Bank-were generated using differential scanning calorimetry (DSC) and analyzed in relation to storage stability. Relatively poor storing...
Poster
Full-text available
Myrtle rust presents a serious threat to New Zealand's indigenous and socioeconomically important Myrtaceae species. • Ex situ conservation is needed to complement in situ collections. • The seed storage physiology of New Zealand's Myrtaceae species is not very well known. • While orthodox seeds can be stored relatively easily in conventional seed...
Article
Citrus seeds are known to have short life spans in conventional seed banks. Seed of most Citrus species show a typical intermediate storage behaviour where they survive desiccation to c. 7-10%. However, longevity is compromised at this low moisture content at sub-zero temperatures. Cryopreservation of zygotic embryos is an option for the long-term...
Article
Full-text available
Cycads are the most endangered of plant groups based on IUCN Red List assessments; all are in Appendix I or II of CITES, about 40% are within biodiversity ‘hotspots,’ and the call for action to improve their protection is long-standing. We contend that progress in this direction will not be made until there is better understanding of cycad pollen,...
Conference Paper
Full-text available
Cryopreservation is preservation of viable cells, tissues, organs and organisms at ultra-low temperatures in liquid or vapour phase of nitrogen. A range of different cryopreservation techniques for preserving plant germplasm have been developed including, controlled rate cooling, encapsulation dehydration, vitrification, encapsulation-vitrification...
Article
Full-text available
Chatham Island forget-me-not Myosotidium hortensia (Boraginaceae) is a monotypic genus endemic to the Chatham Islands of New Zealand. Myosotidium hortensia is threatened in its natural environment by introduced grazing animals and weeds. Further to this, the conservation and reintroduction efforts of M. hortensia are hindered by their dormant seeds...
Conference Paper
Full-text available
Orchid seeds are produced in large numbers in a seed pod. Orchid seed is extremely light and small. The other unique characteristic of orchid seed is, that instead of an endosperm, most common orchid seed consist of an 'air-space' surrounding a small globular embryo within a membranous testa. The airspace volume in orchid seed varies depending on s...
Article
Full-text available
Approximately one fifth of the world’s plants are at risk of extinction. Of these, a significant number exist as populations of few individuals, limited distribution ranges and enormous pressure due to habitat destruction. In China, these most-at-risk species are described as ‘plant species with extremely small populations’ (PSESP). Implementing co...
Poster
Full-text available
Cycad Reproduction (in three languages)
Poster
Full-text available
Cycads and their distribution (in Uganda), in three languages
Conference Paper
Full-text available
Heterogeneity in morphology, physiology and cellular chemistry of plant tissues can compromise successful cryoprotection and cryopreservation. Cryoprotection is a function of exposure time x temperature x permeability for the chosen protectant and diffusion pathway length, as determined by specimen geometry, to provide sufficient dehydration whilst...
Conference Paper
Innovations in plant tissue cryopreservation are necessary for the development of protocols able to overcome the challenges presented by biodiversity (1). Biochemical and biophysical analyses of cryoprotection are required to elucidate the causes and effects of post-cryo survival. Vacuum infiltration vitrification (VIV) is a developing technique th...
Article
Full-text available
The recent acceleration of actions to conserve plant species using ex situ and in situ strategies has revealed the need to understand how these two approaches might be better developed and integrated in their application to tree species. Here we review some of the recent successes relating mainly to tree seed biology that have resulted in the devel...
Article
Full-text available
Heterogeneity in morphology, physiology and cellular chemistry of plant tissues can compromise successful cryoprotection and cryopreservation. Cryoprotection is a function of exposure time × temperature × permeability for the chosen protectant and diffusion pathway length, as determined by specimen geometry, to provide sufficient dehydration whilst...
Article
Full-text available
Desiccation-tolerant plants are able to withstand dehydration and resume normal metabolic functions upon rehydration. These plants can be dehydrated until their cytoplasm enters a 'glassy state' in which molecular mobility is severely reduced. In desiccation-tolerant seeds, longevity can be enhanced by drying and lowering storage temperature. In th...
Article
Although numerous media have been developed to evaluate both orchid seed germination and further seedling development after storage,few studies have attempted to relate nutritional requirements to life history traits. For a range of terrestrial, lithophytic and epiphytic orchid species, comparisons were made of germination on Knudson C, with and wi...
Conference Paper
Millennium Seed Bank- Working together to save plants worldwide Jayanthi Nadarajan Seed Conservation Department, Royal Botanic Gardens Kew, Wakehurst Place, RH17 6TN Ardingly, West Sussex, UK Abstract The Millennium Seed Bank Project (MSBP) International Programme is a nine year global conservation programme (2001-2010), conceived, developed and m...
Article
Full-text available
This project was aimed at developing cryopreservation protocols for one orthodox (Washingtonia filifera) and two recalcitrant palm species namely, Arenga westerhoutii and Thrinax radiata respectively. The experimental strategies involved in vitro tissue manipulation, embryo rescue techniques, application of dehydration and encapsulation-dehydration...
Article
Full-text available
Shoot-tips of Parkia speciosa, a recalcitrant seed producing tropical leguminous tree withstood cryopreservation using encapsulation-vitrification in combination with trehalose preculture. Differential scanning calorimetry (DSC) revealed that trehalose moderated the thermal characteristics of the shoot-tips. A 30 min PVS2 treatment had the lowest g...
Chapter
Cryopreservation is the ultra-low temperature storage (usually in liquid nitrogen at ca. -135 to -196°C) of living cells, tissues and organs capable of resuming normal functions after retrieval from a cryobank. This chapter explains the basic principles of cryopreservation with respect to strategies currently used to cryoprotect the diverse biologi...
Chapter
Although there are several methods of ex situ plant conservation, seed banking is the most efficient for many species, particularly for ease of application and the amount of diversity conserved (Linington and Pritchard 2001). Indeed, seed storage is the main form of ex situ plant genetic resources (PGR) conservation globally, representing about 90%...
Article
Full-text available
Vitrification is a physical process by which a concentrated aqueous solution solidifies into stable amorphous glass at a sufficiently low temperature. This process eliminates the potentially damaging effect of intra- and extracellular crystallization in cryopreservation of plants and animal cells. Sterculia cordata embryos were cryopreserved using...
Article
Full-text available
Optimization of cryopreservation protocol for Sterculia cordata zygotic embryos using Taguchi experiments. Sterculia cordata is a tropical forest tree species bearing intermediate to recalcitrant seeds. This study investigated the effects of seed developmental stage, desiccation time and 6-benzyl aminopurine hormone level in recovery media for cryo...
Article
A robust spectroscopic method for determining total antioxidant activity in aqueous extractions has been applied to tissues from diverse woody plant species, including seeds of Coffea arabica and in vitro shoots from Ribes nigrum, Picea sitchensis and Shorea leprosula. The assay involves scavenging of an ABTS [2,2'-azinobis-(3-ethyl-benzothiazoline...
Article
Cryopreservation is increasingly important for conserving endangered species including tropical rain forest germplasm where optimal cryopreservation protocols must be established rapidly sacrificing little germplasm. Currently, full factorial experiments analysed by ANOVA establish optimal conditions. However, these experiments can contain many tre...
Chapter
This study focuses on the phenological behavior of Neobalanocarpus heimii, a tree species with a high reputation as a ‘primary hardwood’. Twenty years of monthly phenological observations were made on this species at Forest Research Institute Malaysia (FRIM), Pasoh Forest Reserve (Pasoh FR), Ulu Gombak Forest Reserve (Ulu Gombak FR) and Ampang Fore...

Projects

Projects (5)
Project
Classification of dormancy in kiwifruit seeds Kiwifruit seed priming, storage and seedling vigour assessment
Project
Establish viable ex situ collections of Syzygium maire through living collections, tissue culture and cryopreservation
Project
With the current alert on myrtle rust in New Zealand, conservation of the Myrtaceae species in ex situ collections is necessary to complement in situ collections and wild germplasm conservation. Seed banking (at -20oC & 15% RH) is a more promising method for conserving these species; however, for most of the Myrtaceae species the storage physiology of the seeds is unknown. Some of the members of this family have been classified as recalcitrant in storage physiology. Storing these species in conventional seed bank conditions would not be possible. This project will assess the cryopreservation potential of recalcitrant Myrtaceae germplasm.