1) Rooted apical cuttings (RAC) technology uses tissue culture plantlets as mother plants to produce stem cuttings for potato seed multiplication. This provides a low-cost alternative to the capital-intensive aeroponics technology. 2) The RAC technology involves producing cuttings from mother plants in a screenhouse, rooting the cuttings, and then transplanting them to fields for tuber production. RACs have a higher productivity potential than mini tubers. 3) Producing seed potatoes using RAC technology can make high-quality, disease-free planting materials available to smallholder farmers in a timely manner at low cost. This can boost

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2. Shrilatha, K. A.
M.Sc. (Horticulture)
UHS19PGM1238
UNIVERSITY OF HORTICULTURAL SCIENCES, BAGALKOT
Department of Vegetable Science
College of Horticulture, Bagalkot
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Rooted apical cutting (RAC) technology in potato.

3. Introduction
• Potato is one of the important food crop and it is important for its
nutritional security.
• India is the second largest producer and consumer of potato in the
world.
• Potato production has steadily increased from around 8.3 million tonnes
in 1980 to 48.6 million tonnes in 2018.
• In the past ten years, the production has increased more than 60 percent
with both area and yield contributing to the increase.
• Expanded potato production in the mid elevations and the lowlands the
need for planting material arises.
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4. Because seed accounts for 40-50% of the total cost of production, this is a
huge burden for small farmers.
Accessing good-quality planting materials at affordable prices for
small and marginal farmers in many potato-growing states.
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5. • The high cost of seed has led some small farmers to use discarded small-
sized potato as seed from previous harvests or purchase from other
farmers or in the local markets.
• Use of this low-quality seed, which is often infected with seed-borne
pathogens leads to low yields.
• Even if farmers want to purchase good-quality seed at such a high price,
there is still no guarantee they will be able to obtain high-quality of seed
in a timely manner because of the long distances (up to 2,000 km).
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6. Two things need to
happen
Then, how to solve the potato
seed problem?
Second, this low-cost technology
needs to be promoted in the
production belts.
First, a low-cost seed multiplication
technology, should be made available
instead of capital intensive aeroponics
technology.
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7. • If a low-cost technology can be made available to produce seed potato at
cheaper price then these eastern and southern states have immense potential
to increase potato production by improving productivity and lowering cost
of production.
• Because the soil and environment in many parts of the eastern and southern
regions are suitable for cultivating potato seed in rabi season (October-
March) and in some areas like Hassan in Karnataka and Koraput in Odisha
it can be grown in kharif season (July-October) also.
• Second, this low-cost technology needs to be promoted in the production
belts so that progressive farmers, farmer producer organizations (FPOs),
and other small entrepreneurs in potato-growing states can adopt seed
potato production and supply planting material to the farmers in timely
manner.
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8. Rooted apical cutting (RAC) - A novel technology
to boost potato seed system.
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9. Rooted apical cutting (RAC)
Cutting is a transplant produced in a screenhouse from tissue culture
plants and handled the same way in the field as a nursery-grown seedling.
• As cuttings are tissue culture material it is clean and disease free.
• After rooting these plantlets can be planted directly into the field or used for
production of clean potato tuber seed stocks.
• A novel technology to boost potato seed system.
Apical cuttings provide an alternative to mini tubers, not a replacement.
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10. Both aeroponics and apical cuttings involve tissue culture plantlets.
In aeroponics tissue culture plantlets
are used to produce mini tubers using
capital intensive aeroponic technology
in screen house.
Whereas in apical cuttings the
tissue culture plantlets are used
as mother plants in coco pits for
producing cuttings.
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11. Difference
Apical stem cuttings Stem cuttings
Produced from tissue culture
mother plant.
Produced from mature sprouted
tubers.
Yield potential 10 -20+
tubers/cuttings
Yield potential 2-3 tubers/stem.
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12. Steps involved in production of rooted apical cuttings
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13. Production of cuttings
in screenhouse
Production of tubers
in the field
Two phases
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14. Fig. 1 :An Overview of multiplication of Apical Stem cuttings of Potato
Tissue culture Mother plants Mother plants transferred to beds
Continuous multiplication of ASCs
from mother plants & sub mothers
Seedlings ready for field transplanting
seedlings 14
After some days of growth period,
2-3cm Apical stems are removed.
And transplanted to the protrays
or other media filled beds.
Takes 14 days to root
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15. Fig. 2: Planting and management of potato rooted apical cuttings in field
Nyawade and Parker, 2019
Demarcate the layout and dig
out the soil.
Mark the planting lines, holes and water
the bed to moisten it-if the soil is dry.
Harvest 2 weeks after dehaulming,
grade and store the tubers.
-
Replace the dead cuttings, perform
weeding, hilling, topdressing (after weeks)
and control pests and diseases (based on
keen monitoring).
2
Raise the bed to 3-5 cm above the
soil line and levelized the soil.
Transplant the cuttings at 30×30cm
spacing, ensuring the collar is
buried with the soil.
Dehulm when 70-80%
of tubers are in egg size.
Erect a shade over the bed-this is
only done if the weather is too hot,
remove within 2 weeks.
Weigh the fertilizer, spread and
properly mix with the soil then firm
the soil.
Spray the cuttings against
cutworm and late blight.
Control late blight, monitor
diseases, check the tuber
sizes.
Install a placard labelled
with variety name, number
planted and date of planting.
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16. Fig. 3: (a) Demarcations (b) depressions at planting.
• First hilling after 2 weeks and
repeat hilling at 2-3 weeks after
the first hilling.
•The mound that forms after the
second hilling should be about 30
cm high.
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Fig. 4: hilling

17. Fig. 5: Production of seed from rooted cuttings, picture taken 5 weeks after transplanting (left),
and at harvest 90 days after planting showing harvest, which averaged 28 tubers/cutting (right).
CIP. 2018.
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18. Productivity of cuttings in the field.
• With high productivity of cuttings, selling seed after two seasons of
multiplication becomes economical, and after three seasons highly
profitable, noting certified seed from mini tubers is sold after three to four
seasons of multiplication.
• Apical cuttings produce 10 to 25+ tubers per cutting, compared to 5 to 10
tubers/mini tuber.
• Spacing required for apical cuttings is less as it produce single stem per
cuttings compared to the minitubers, it produce 3-4 hulms per tuber.
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19. Benefits of apical cuttings in field seed production
Parker (2020)
High productivity
Profitable after 2 seasons of multiplication
Suitable where limited land for multiple seasons of
bulking commercial seed
Working with units of 1,000 cuttings
Produce disease free quality planting material
Rapid maturity – starts tuberization 35 days after
transplanting.
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20. There is a wide scope for production of seed tubers through apical stem
cuttings in potato growing belts.
Large scale mass multiplication was possible in short period through tissue
culture and nursery production under polyhouse throughout the year.
Production of true to type and disease free plants.
Scope for multiplication of desired high yielding released varieties.
At very reasonable price planting material can be produced.
In this technology, flexibility of potato cultivation is possible during both
Kharif and Rabi seasons (May-December).
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Scope and advantages of potato seed production through
apical stem cuttings.

21. Cont...
Job opportunities at three different phases (tissue culture plantlet
production, mother bed production cum apical stem cuttings, pro-tray
production of rooted apical stem cuttings and seed production of G0)
More possibility of doubling income at different phases.
Through apical stem cuttings technology, it is possible to avoid market
fluctuation for seed tubers during the commencement of season.
From this technology, timely availability of seed material can be
achieved.
Self sufficiency of seed material for potato growing states can be
achieved.
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22. • Producing seed on-farm from apical cuttings is economical and
produces high-quality seed.
• Rooted apical cuttings enable potato farmers to access high-quality
disease pathogen free planting material in time at low cost.
• Which can be of better quality than purchased seed.
• Increase the net returns of the farmers by increasing tuber yield and
reduce the transportation charge.
• Alternative to both traditional and capital intensive aeroponics
technology.
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