Citation: Adly, W.M.R.M.; Mazrou,
Y.S.A.; EL-Denary, M.E.; Mohamed,
M.A.; Abd El-Salam, E.-S.T.; Fouad,
A.S. Boosting Polyamines to Enhance
Shoot Regeneration in Potato
(Solanum tuberosum L.) Using AgNO
3
.
Horticulturae 2022, 8, 113.
https://doi.org/10.3390/
horticulturae8020113
Academic Editor: Kin-Ying To
Received: 13 December 2021
Accepted: 17 January 2022
Published: 27 January 2022
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
Copyright: © 2022 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
horticulturae
Article
Boosting Polyamines to Enhance Shoot Regeneration in Potato
(Solanum tuberosum L.) Using AgNO
3
Walaa M. R. M. Adly
1
, Yasser S. A. Mazrou
2,3
, Mohammad E. EL-Denary
1,
*, Mahasen A. Mohamed
1
,
El-Sayed T. Abd El-Salam
4
and Ahmed S. Fouad
4
1
Horticulture Research Institute, Agriculture Research Center, Giza 12619, Egypt;
DR.Walaa.Adly@gmail.com (W.M.R.M.A.); dr.mahasen.hakem@gmail.com (M.A.M.)
2
Business Administration Department, Community College, King Khalid University, Guraiger,
Abha 62529, Saudi Arabia
3
Department of Agriculture Economic, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt;
yasser.mazroua@agr.tanta.edu.eg
4
Botany and Microbiology Department, Faculty of Science, Cairo University, Giza 12613, Egypt;
tsayed1969@hotmail.com (E.-S.T.A.E.-S.); ahmedsfouad@yahoo.com (A.S.F.)
* Correspondence: dr.m.eldenary@gmail.com
Abstract: Advancements in shoot regeneration systems support biotechnology-based tools used
in the genetic improvement of plant crops. This study aims to enhance shoot regeneration in
potatoes by boosting polyamine content by adding AgNO
3
to the shoot regeneration medium (MS
medium supplemented with 30 g L
−1
sucrose, 100 mg L
−1
myoinositol, and 2.25 BA mg L
−1
). Five
concentrations of AgNO
3
(2, 4, 6, 8, and 10 mg L
−1
) were used in addition to a control. The effect of
AgNO
3
on regeneration assumed a more or less concentration-dependent bell-shaped curve peaking
at 4 mg L
−1
. Enhancements in shoot regeneration were attributed to the known role of AgNO
3
as an
ethylene action blocker in addition to improvements in polyamine accumulation without an increase
in H
2
O
2
content, lipid peroxidation, or DNA damage. The uncoupling of shoot regeneration and
polyamine content recorded at high AgNO
3
concentrations can be attributed to the consumption of
polyamines to counteract the synchronized oxidative stress manifested by increases in H
2
O
2
content,
lipid peroxidation, and DNA damage.
Keywords: potato; polyamines; callus; shoot regeneration; H
2
O
2
; MDA; comet
1. Introduction
Potato (Solanum tuberosum) is the most important non-cereal food crop with annual
world production of 370 million tons harvested from 17.34 million hectares (FAO 2019
https://www.fao.org/faostat/ar/#data/QCL, accessed on 11 November 2021). Tubers are
an essential origin for energy and protein. They also introduce essential nutrients to a diet,
including vitamins (B
1
,B
3
,B
6
and C), minerals (potassium, phosphorus, magnesium, zinc,
and iron) in addition to folate, pantothenic acid, riboflavin, and dietary fiber [1]. Compared
to other food crops, potatoes can produce more energy, proteins, minerals, and vitamins
per unit of time and land area [2]. In addition to indoor uses, potatoes are used in many
food industries [3] that generate a huge amount of peel used in bioethanol production [4].
Conventional potato breeding is a difficult task due to the tetraploid nature and high
heterozygosity of the potato genomes. The first is responsible for inbreeding depression
and intra-species incompatibilities, while the second prevents the incorporation of new
traits through conventional breeding [5]. In addition, searching for functional genetic
variability in wild relatives is laborious and time-consuming [6,7].
Biotechnology can hasten potato breeding through in vitro selection [8] and transfor-
mation [9]. However, biotechnological tools require establishing a regeneration system to
obtain genetically improved lines [10]. Thus, studying factors affecting regeneration in
Horticulturae 2022, 8, 113. https://doi.org/10.3390/horticulturae8020113 https://www.mdpi.com/journal/horticulturae