The document provides information on the taxonomy, botany, morphology, germplasms, varieties, ecology, cultivation, harvesting, yields, and pests and diseases of sweet potato (Ipomoea batatas). Key points include that sweet potato is a hexaploid species in the family Convolvulaceae, it is cultivated in tropical and subtropical regions, and it faces numerous fungal, bacterial, viral and nematode diseases as well as insect pests that require control methods.

1. Sweet potato
Ipomoea batatas

2. World Production

5. Taxonomy
Kingdom: Plantae (Plants)
Subkingdom: Tracheobionta (Vascular plants)
Superdivision: Spermatophyta (Seed plants)
Division: Magnoliophyta (Flowering plants)
Class: Magnoliopsida (Dicotyledons)
Subclass: Asteridae
Order: Solanales
Family: Convolvulaceae (Morning-glory family)
Genus: Ipomoea L. (morning-glory)
Species: Ipomoea batatas (L.) Lam.
sweetpotato

6. Botany
It is the only hexaploid (6x = 90) in this section
its origin is unknown
Section Batatas contains approximately 12
other species
most are diploid (2n = 30)
a few tetraploids (4x = 60).
Tetraploid sweet potatoes have been collected
in the wild although rarely
Ipomoea trifida, a diploid, is purported to be
one of the likely progenitors of sweet potato.

7. Botany
Species in section Batatas have been
shown to contain unreduced gametes
the derivation of the hexaploid sweetpotato
remains a mystery
The major center of diversity for I. batatas:
northwestern South America (northern Peru,
southern Ecuador)
sub-Saharan Africa
Papua New Guinea
Indonesia

8. Morphology
leaves
ovate-cordate
borne on long petioles
palmately veined
angular or lobed
depending on variety
green
purplish.

9. Morphology
flowers rare, especially in US
like common morning glory
white or pale violet
axillary
funnel-shaped
borne singly or in cymes on short peduncles;
pods round; seeds 1–4 per pod, flattened, hard-coated,
angular.

10. Germplasms
Reported from
the Indonesia-Indochina
Middle and South American Centers of Diversity
more than forty cvs that have been grown in
the US, about 10 are of commercial value
two categories:
food types
feed types.
further divided into dry or firm types and
moist or soft types.

11. Sweetpotato

12. Potato

13. Peanut

14. Varieties
The present outstanding soft-fleshed cvs
'Porto Rico',
'Nancy Hall',
'Triumph', and
'Australian Canner';
firm-fleshed types
'Big-stem Jersey',
'Yellow Jersey',
'Maryland Golden', and
'Orlis' (Jersey orange).

15. Ecology
Sweetpotato is cultivated
in tropical
subtropical lowland agroecologies
The crop will grow with between 15°C and 35°C
Storage roots are sensitive to changes in soil
temperature depending on stage of root
development
a drought-tolerant crop
deep rooted
developing storage roots under very dry conditions
grow best in a sandy loam, well-drained soil
have been produced at altitudes >2000m and as
far north as Canada.

16. Morphology
Tuberous-rooted perennial,
usually grown as an annual
top herbaceous
drying back to ground each year
stems forming a running vine up to 4 m
long
usually prostrate and slender with milky
juice
lateral stem-branches arising from the
short stem
usually not branched.

17. Ecology
tolerate annual precipitation of 3.1 to
42.9 dm (mean of 153 cases = 15.0),
pH of 4.3 to 8.7 (mean of 88 cases =
6.4)
Well-adapted to tropical and
subtropical climates
Days and nights must be fairly warm.

18. Ecology
fairly drought-tolerant
Soils must be well-drained.
Subsoils of clay are satisfactory unless they
are tight and sticky
Some friable, well-drained loams and silt
loams are highly productive
Excellent soils have surface layers more than
30 cm in depth, those from 15–30 cm are
considered good
Slopes should be gentle, with little tendency
to become eroded.

19. Cultivation
In tropical areas, sweetpotatoes flower and cross-pollinate
easily
seeds are rarely used for propagation purposes
propagation is by vegetative means, from
transplants produced by bedding mother roots, or
from rooted cuttings.
grown over a wide range on farms of various types:
truck farms,
dairy farms,
cotton farms,
tobacco farms,
corn-and-hog farms,
and others..

20. Harvesting
Sweetpotatoes develop a substantial amount of
the total yield in the last 4–5 weeks before frost.
For large yields 130 to 150 days growth is required.
Early harvested crops are lower in carotene
content and in total solids.
Probably the best time to harvest for storage is
after the leaves show slight yellowing.
A 16- to 18-inch tractor-drawn turning plow with a
vine-cutting colter in front of it is probably the best
tool for harvesting.

21. Yields and Economics
Average yields vary from 17.5 to 27.5 MT/ha,
depending on the cv and growing conditions .
Sweetpotatoes have long been considered the
second most important vegetable crop in the US,
second only to white or Irish potatoes.
Spain is major producer in Europe; India grows
sweetpotato in all states and it ranks third in
importance among tuber crops, exceeded only by
potato and cassava.
In China, where it was introduced in 1594,
sweetpotato is often used more than rice and has
been used to relieve famines.

22. Biotic Factors
Sweetpotato is subject to injury from a number of
diseases that may attack the young plants in the
hot bed or the growing crop in the field or may
cause decay in storage.
The worst of these are stem-rot, black-rot, foot-rot,
soft-rot or ring-rot,and in the Southwest, root-rot.
These are described and illustrated, and control
measures are given in Farmers' Bulletin No. 1059,
Sweet Potato Diseases.
The sweetpotato is not seriously injured by many
insects but the sweetpotato root weevil has been
very injurious in sections of the South, especially in
the Gulf States.

23. Pests and Diseases
Cutworms frequently destroy the young
plants by cutting them off soon after
they are set in the field .
Agriculture Handbook No. 165 (1960)
lists the following as affecting this
species:
Albugo ipomoeae-panduratae (white rust),
Alternaria sp. (secondary leaf spot),
Aspergillus spp. (secondary storage rot),

24. Pests and Diseases
Botrytis cinerea (gray-mold rot),
Cercospora sp. (leaf spot),
Choanephora cucurbitarum (leaf mold),
Coleosporium ipomoeae (rust),
Diaporthe batatas (dry rot of roots, stem rot),
Elsinoe batatas (spot anthracnose),
Endoconidiophora fimbriata (black rot of roots and stems),
Epicoccum sp. (storage rot),
Erwinia carotovora (bacterial soft rot),
Fuligo violacea, Fusarium oxysporum (surface rot of roots in
storage),
F. oxysporum.f. batatas (stem rot),
Helicobasidium purpureum (root rot),
Hypomyces ipomoeae,
Macrophomina phaseoli (charcoal rot of stored roots, stem rot),

25. Pests and Diseases
Meliola clavulata and M. malacotricha (black mildew),
Monilochaetes infuscans,
Mucor racemosus (storage rot),
Penicillium sp. (bluemold rot),
Pestalotia batatae (on roots),
Phyllosticta batatas (leaf blight),
Phymatotrichum omnivorum (root rot),
Physarum cinereum, P. plumbeum, Phytophthora sp. (root rot),
Plenodomus destruens (foot rot of stems and roots),
Pyrenophora terrestris (pink rot),
Pythium spp. (rootlet rot, mottle necrosis of mature roots, leak and
ring rot in transit and storage),
Rhizoctonia solani (sprout rot, rootlet rot, stem canker),
Rhizopus spp. (soft rot, ring rot of stored roots),
Schizophyllum commune (dry rot of roots),

26. Pests and Diseases
Sclerotinia sp. (storage rot following chilling), S. minor (sprout rot in
seedbeds),
Sclerotium rolfsii (southern blight, cottony rot),
Septoria bataticola (leaf spot),
Streptomyces ipomoea (soil rot),
Trichoderma spp. (punky rot of stored roots),
Verticillum albo-altrum (wilt) (Ag. Handbook 165, 1960).
Several viruses are known to infect sweetpotatoes:
A virus,
B virus,
Feathery mottle (sweetpotato internal cork virus),
Mottle and Mosaic,
Tobacco mosaic,
Vein-clearing, and
Mizugusare disease.
Internal brown spot is due to boron deficiency.

27. Pests and Diseases
many nematodes have been reported on the crop:
Aphelenchoides besseyii,
Aphelenchus avenae
Belonolaimus gracilis
B. Longicaudatus
Criconemella onoensis
Ditylenchus destructor
D. dipsaci
Helicotylenchus multicinctus
H. Cavenessi
H. Concavus
H. Microcephalus
H. Pseudorobustus
Hemicriconemoides cocophillus
Meloidogyne hapla
M. Incognita
M. incognita acrita
M. Javanica
Nothotylenchus affinis
Pratylenchus brachyurus
P. Coffeae
P. Pratensis
P. Penetrans
P. Scribneri
P. Thornei
P. Zeae
Quinisulicius capitatus
Radopholus similis
Rotylenchulus reniformis
Scutellonema brachyurum
S. Clathricaudatum
Tylenchorhynchus annulatus
T. claytoni, and
Xiphinema americanum

28. Pests and Diseases
Insects attacking sweetpotato plants:
Long-horn beetles (Cerambicid),
Sweetpotato flea beetle (Chaetosnema confinis),
Wireworms (Conoderus amplicollis, C. falli, C. vespertinus),
Sweetpotato weevil (Cylas formicarius elegantulus),
Cucumber beetles (Diabrotica balteata and D. undecim-punctata),
American plum borer (Euzophera semifuneralis),
Wireworm (Melanotus communis),
Tortoise beetles (Metriona sp.),
Flower beelte (Notoxus calcaratus),
Variegated-cutworm beetles (Systena blanda, S. elongata, S.
frontalis),
Sweetpotato leaf-beetle (Typophorus nigritus viridicyaneus).
Methods for control should be obtained from local
agricultural agents 

29. Thank you