TITLE:
Synthetic Seed Preparation, Germination and Plantlet Regeneration of Litchi (Litchi chinensis Sonn.)
AUTHORS:
D. K. Das, A. Rahman, Dipti Kumari, Nutan Kumari
KEYWORDS:
Encapsulation, Germination, Plantlet Regeneration, Somatic Embryos
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.7 No.10,
July
22,
2016
ABSTRACT: Litchi chinensis sonn.)
ranks second after mango amongst the most important fruit crops cultivated
worldwide. Litchi is a very valuable crop throughout the world because it is a
table fruit and wines are also produced from it. The existing cultivars are
highly polyploidy and heterozygous in nature. It is propagated through air
layering and marcottage methods and storability is very low. Synthetic seeds
can be stored for a long time and its genetic constitution could remain the
same. For germplasm maintenance and clonal propagation, synthetic seeds can be
used. Somatic embryogenesis has been reported from anther or embryogenic
suspension culture in various species of litchi. Regeneration via organogenesis
and somatic embryogenesis from zygotic embryos has also been reported in
certain species. Developing a methodology for getting somatic embryogenesis
with a high frequency from zygotic embryos which is available once in a year,
would be particularly useful for genetic improvement of litchi. Cotyledonary
stage somatic embryos developed from zygotic embryos were encapsulated in 2%
alginate gel. The encapsulated somatic embryos (ESEs) germinated successfully
on 0.7% agar medium containing 3% sucrose concentration in NN basal medium
(half strength of major and minor salts) with 1 mg·l-1 of gibbrellic
acid. Percentage germination and plantlet development for ESEs was higher than
that of non encapsulated embryos (NSEs). In comparison to different hormones,
gibberellic acid has a significant influence on the germination rate of ESEs
after one week of dehydration was seen maximum at 9% sucrose and abscisic acid
(1 mg·l-1) in half strength of major and minor salts in Nitsch and
Nitsch medium resulting in extended storage up to 90 days without loss in germination
potential and capability to regenerate into plantlets. Normally developed
plantlets regenerated from ESEs were successfully adapted to soil to obtain a
full grown plant.