16 Sep 2021

Tissue Culture of Potato (Part-1)

Anjali Singh, MS

As a content and community manager, I leverage my expertise in plant biotechnology, passion for tissue culture, and writing skills to create compelling articles, simplifying intricate scientific concepts, and address your inquiries. As a dedicated science communicator, I strive to spark curiosity and foster a love for science in my audience.

Table of Contents

Introduction

Potatoes are one of the globally important crops in agriculture production around the world. It’s grown in 180 countries, being predominantly produced in Asia, Europe, South America, and North and Central America.

The beginning of potato cultivation goes back to 150-170 years. Based on the archaeological and genetic evidence the first domestications occurred at least 8000 years ago in the high Andes of Peru and Bolivia.

Today, the plant is used as a staple food in many countries. But very few are aware that it also has a number of medicinal properties. This article will cover all about potatoes, their cultivation methods, and the procedure to grow these plants under in vitro conditions for their mass production.

Description of Potato Morphology

The species Solanum is considered native to Central and South America. Any cool-temperate regions and at higher altitudes in the tropics can support the growth of the plant.

Potato plants are herbaceous, perennial that grows about 60 cm high, depending on their variety. After flowering, fruiting, and tuber formation, their leaves start dying back (a sign of senescence/aging).

The plants bear white, pink, blue, or purple flowers with yellow stamens in clusters. They are pollinated by insects such as bumblebees but sometimes self-fertilization also occurs. The tubers that grow as an underground stem are the only edible and commercially important part of the plant.

Each tuber has two to ten ‘eyes’ or buds arranged spirally around its surface and is capable of producing new shoots and plants under favorable conditions.

Tubers, rather than from true seeds, are the means to vegetatively propagate these plants for commercial purposes. Europe is the largest manufacturer of potatoes with its high production in Ukraine, Poland, Belarus, Germany, Romania, the Netherlands, and France.

Cultivation of Potatoes

Seeds or potato tubers are used to grow potato plants. But, the plants obtained from seeds show high genetic variations, whereas, plants grown through tubers are clones of the parent plant.

Moreover, the propagation of potato plants through seeds is a labor-intensive and time-consuming process with progenies have poor vigor and lower yields.

For these reasons, tubers are preferred over seeds for potato propagation. The tubers are cut into pieces with at least one or two eyes (seed tubers), which later initiate the plant development.

But, growing potatoes using tubers are not without limitation. It includes:

It may also contain diseases and pests, affecting the tuber quality and yield of the harvest.
High costs of transportation and storage
Low multiplication rate

In vitro Micropropagation of Potato

Potato tubers are easy to sow and grow in natural conditions. And, have tremendous advantages in terms of storage, transportation, and production practices. But, the lubrication process is difficult, which can be induced under in vitro conditions. Further, virus propagating potatoes even after virus testing stem cutting only 800-900 plants can be produced over the first three years of starting from a single plant.

Whereas, using in vitro approach to culture potatoes have the potential to produce many thousand plants within a single year. And, also, it’s also susceptible to many bacterial, viral, and fungal pathogens. And, the production of disease-free seed tubers is necessary to maintain adequate yields.

To ensure maximum genetic uniformity in the cultures, it’s essential to avoid the formation of adventitious shoots. It’s because:

The adventitious shoots frequently derive from single or very small groups of cells and therefore they are more prone to spontaneous or induced mutations.
During the regeneration of potato plants from protoplasts, the differentiated tissues of potatoes are a strong source of genetic variations.
Some cultivars are periclinal chimeras. So, they break into separate genotypes following adventitious shoots formation.

Procedure

Given below is a procedure of in vitro propagation of Solanum tubersoum taken from the study of HUSSEY, G., & STACEY, N. J. (1981). In Vitro Propagation of Potato (Solanum tuberosum L.). Annals of Botany, 48(6), 787–796. doi:10.1093/oxfordjournals.aob.a0

Plant Material

Collect tubers from disease-free plants.

Establishment of cultures in the lab

Wash tubers with clean water and cut them into small pieces of 15 mm3 each containing a sprout.
Plant one into a 5 cm pot containing a mixture of Perlite and crushed flint (2:1 by volume) watered with Hoagland's nutrient solution.
Raise the resulting shoot under a framework covered with Tygan netting. Main the controlled environment in the cabinet at 20 °C and a day-length of 16 h provided by white fluorescent tubes at an intensity of 8000 lx.
Then, from the grown plants collect 5mm stem with a single node as an explant and sterilize in 1 percent aqueous sodium hypochlorite.
Wash the explant twice in sterile distilled water.

Nutrient Media Preparation

Prepare the nutrient media using a half-strength or a full-strength salt mixture of Murashige and Skoog together with100 mg/L inositol, 0-5 mg/L thiamine-HCl, 10mg/L pyridoxine-HCl, 50 mg/L nicotinic acid, and 2-5 mg/L pantothenic acid.
Add 3% sucrose to the above mixture.
Use the medium either as a liquid or solidified with 0-7 percent agar after adjusting the pH to 5-9.
The autoclave the prepared media at 121 °C for 15 min

Culture Conditions

Grow cultures either in 90 ml metal screw-capped polystyrene jars each containing 20 ml of agar medium or in 9 cm Petri dishes each containing 15 ml of liquid medium. Keep the plants at 25 °C in continuous light with an intensity of 6000-8000 lx.

After a couple of months, all your plantlets will be ready!

If the procedure works to grow your potato plant. Do write to us at info@plantcelltechnology.com. And, if you require any tissue culture chemical or equipment, get them from the PCT store right now!

Happy Culturing!