This includes a detailed explanation on phytoplasma, its prevalence in India, properties, history, major plant diseases it causes, with its symptoms, vectors involved and where it was reported in India. And this also included minor diseases it causes in other crops, along with cases of mixed infections reported in India, and detection and management of the diseases.

1. PHYTOPLASMAS -The
“Crouching Tiger” threat to Indian
Agriculture
WELCOME

2. SYMPTOMS CAUSED BY
PHYTOPLASMAS
ABHISEK RATH
I.D. NO – PGS19AGR8175
DEPARTMENT OF PLANT PATHOLOGY
COLLEGE OF AGRICULTURE
UAS DHARWAD – 580 005
http://www.free-powerpoint-templates-design.com

3. CONTENT
INTRODUCTION 01
PROPERTIES & HISTORY 02
IMPORTANT PHYTOPLASMA DISEASES 03
IDENTIFICATION AND MANAGEMENT 04

4. INTRODUCTION
I. Phytoplasmas [class Mollicutes] are obligate plant pathogenic prokaryotes (minute
bacterial parasites) lacking cell wall with pleomorphic shape present in plant phloem
tissue and of the insect vectors that involved in plant to plant transmission.
II. Phytoplasmas causes more than 600 plant disease worldwide with a noticeable impact on
agriculture economics and 129 plant species have been reported to be associated with this.
III. In India, recent evidence showed that phytoplasma associated with plants including
vegetables, fruits, trees, ornamentals, sugarcane, palms, oil crops and weeds are
increasing at an alarming rate (Rao, 2017).
IV. Phytoplasmas-related diseases are expected to increase because global warming / climate
change is advantageous to the cold-sensitive phytoplasmas vectors and depends upon the
feeding range of their insect vectors.

5. VI. They are transmitted by phloem-sucking leafhopper species, primarily belonging to
the family Cicadellidae, Cixiidae, and Psyllidae (Weintraub and Beanland, 2006).
VII. During the last 5 years more than 40 phytoplasmas are identified in various plant
species including crops, fruit trees, ornamentals, sugarcane, grasses and weeds on
the basis of sequence analysis and comparison of 16S rRNA, sec A gene, tuf gene,
gyrA, gyrB, dnaB, groEL and leu C gene.
VIII. 10 phytoplasma ribosomal groups were identified mainly from north and south
areas while only a limited number of phytoplasma diseases have been recorded in
Eastern, Western and Central parts of the country.
IX. Phytoplasmal groups in India showed a wide geographical distribution especially in
North Eastern and Southern parts of the country. So far, these diseases have been
identified in 17 states of India.

6. PROPERTIES
Unicellular prokaryote, lack cell
wall, Pleomorphic, small
(diameter less than 1 µm).
Has a 3-layered Lipo -protein
plasma membrane.
Intracellular , Obligate
parasites.
Low G+C content
(sometimes 23 %).
Transmits via Grafting, dodder,
and insects - Leafhopper, Plant
hopper, Psyllids (survive and
replicate).
Phytoplasmas reproduce in the
haemolymph of insects before
travelling to salivary glands.

7. PROPERTIES
Don‟t required sterols for
growth.
size ranges from 200-800 nm.
Inhabit in phloem sieve of plants
and salivary glands of insects.
Sensitive to Tetracycline and
insensitive to Penicillin.
Based on molecular data, new
taxonomy and designation has
evolved as “Candidatus”
Phytoplasma species.
Genome size ranges from 530
kb to 1185 kb.
Cannot be grown on
artificial media.
Has both DNA & RNA.

8. 1889
1898
1929
1967
1994
1883
The International Organisation of Mycoplasmology proposed to the sub-
committee on taxonomy of “mollicutes” that the term “Phytoplasma” replace
the trivial term MLO.
Phytoplasmas were discovered by Doi and Ishiie in Japan and reported agents
resembling mycoplasma in the sieve tubes while studying with Mulberry
Dwarf Disease. They termed them as Mycoplasma like organisms. From 1967
to 1994, these Mollicutes were referred as MLOs.
Julien Nowak used the term mycoplasma taxonomically for the bovine – PPLO
Mycoplasma was first used by A. B. Frank to describe an altered state of
plant cell cytoplasm by infiltration of fungus like organisms.
Louis Pasteur described the first Mycoplasma (Mycoplasma mycoides) as the
causal agent of Pleuro Pneumonia in Cattle.
TIMELINE
Nocard and Roux isolated and cultured first and called it as Pleuro
Pneumonia Like Organisms (PPLO).

9. HISTORY IN INDIA
I. The history of phytoplasma diseases in India is more than 100 years old. Root (wilt)
disease of coconut was first reported in the former state of Travancore in 1874, and
became very much evident in 1882 (Butler, 1908; Pillai, 1911; Varghese, 1934).
II. After this sandal spike disease was described in the Coorg district of Karnataka in
early 19th century (McCarthy, 1899).
III. The yellow leaf disease of arecanut was first reported in 1914 from Moovattupuzha,
Meenachal and Chalakudi areas of central Kerala (Nambiar, 1949).
IV. Thomas and Krishnaswamy (1939) reported brinjal little leaf disease suspected to be of
viral in nature, where phytoplasma presence was later confirmed (Varma et al., 1975;
Shanta and Lakshamanan, 1984; Mitra, 1993).
V. The occurrence of sesame phyllody in South India in early 19th century (Kashiram,
1930; Vasudeva and Shambhi, 1955) was confirmed with phytoplasma presence
(Cousin et al., 1971).
VI. Sugarcane grassy shoot disease (SCGS) was identified as the most important
phytoplasma disease in the Indian subcontinent, after first report in the Ahmed nagar
district of Bombay in 1949 (Chona, 1958).

10. SYMPTOMS
I. PHYLLODY
II. LITTLE LEAF
III. YELLOW DWARF
IV. BIG BUD
V. STERILITY OF FLOWERS
VI. WITCHES’ BROOM
VII. SLENDER SHOOTS
VIII.STUNTING
IX. LEAF CURLING
X. VIRESCENCE
XI. GENERALIZED DECLINE
XII. BUNCHY GROWTH
PERIWINKLE
PHYLLODY
CHICKPEA
PHYLLODY
ROSE
PHYLLODY
TOMATO
BIG BUD
RICE YELLOW
DWARF
TRIFOLLIATE
PHYLLODY

11. SYMPTOMS BRASSICA
PHYLLODY
SUGARCANE
GRASSY SHOOT
ASTER
YELLOW
SANDAL
SPIKE
SESAME
PHYLLODY
BAMBOO
WITCHES’ BROOM

12. SYMPTOMS CARROT
YELLOW
BRINJAL
LITTLE LEAF
GRAPEVINE
YELLOW
LETHAL
YELLOWING
LIME
WITCH BROOMS

13. SUGARCANE GRASSY SHOOT
I. Rao et al (2005) reported that phytoplasma is associated with two
major sugarcane diseases, grassy shoot (SCGS) and white leaf
(SCWL).
II. Sugarcane yellow leaf syndrome (YLS) is another reported
syndrome associated with a luteovirus and a phytoplasma.
III. SCGS causes 70 to 100% losses in susceptible varieties with great
economic concern to both farmers and sugar industry. Yield losses
caused by SCGS in ratoons crops are higher when primary
infection appears early in the crop.
IV. This disease was first observed near Belapur in the Ahmednagar
district of Maharashtra in 1949 (Chona, 1958) but now it has
been recorded in all sugarcane growing states of India.
V. Thilagavathi et al. (2011) identified peanut witches‟ broom
phytoplasma (16SrII) on Beta vulgaris L. sub sp. vulgaris var.
altissima from Tamil Nadu state in 2008.

14. SUGARCANE GRASSY SHOOT
SYMPTOMS :
I. Rane and Dakshindas (1962) reported that grassy shoot, chlorotic leaves, and shoot
proliferation are the most common symptoms associated with the disease and named
it grassy shoot.
II. SCGS disease is also characterized by the production of a large number of thin,
slender, adventitious tillers from the base of the affected plants giving a crowded and
grassy appearance .
III. This excessive growth gives rise to a dense or crowded bunch of tillers bearing chlorotic
leaves with a soft texture. There is a loss of chlorophyll from total green to white in the
leaves of infected plants.
IV. Affected plants do not produce millable canes .The disease is more pronounced in the
ratoon crops.
Transmitted by Setts, Leafhoppers (Saccharosydne saccharivora).

15. SUGARCANE
GRASSY
SHHOT
SYMPTOMS CAUSED BY SUGARCANE GRASSY SHOOT DISEASE.
(A) PROLIFERATION OF CHLOROTIC TILLERS AT THE BASE OF A
SUSCEPTIBLE VARIETY;
(B) BUD SPROUTING IN SCGS INFECTED CANES STALKS;
(C) GRASSY SHOOT APPEARANCE IN SCGS INFECTED CLUMPS.
(a) (b) (c)

16. SESAME PHYLLODY
Among the major biotic constraints, phyllody, virescence and little
leaf disease is the major limiting factor causing 34% yield losses
(Rao et al., 2015).
SYMPTOMS :
I. Plant becomes stunted, shows reduction in growth.
II. Floral parts modified to leafy structures bearing no fruits and
seeds.
III. Virescence, proliferation, seed capsule cracking, formation of
dark exudates on foliage and floral part can be seen.
Transmitted by Leafhoppers (Orosius albicinctus).

17. ASTER YELLOW
HOST CROP : carrot(mostly) - > 10-85% loss.
In processed carrots, the presence of 15% of aster yellows-infected
carrots results in a rejection of the entire product due to their
distasteful flavour.
SYMPTOMS :
I. Yellowing and dwarfing of plants.
II. Abnormal production of shoots, sterility of flowers,
malformation of organs.
III. Witches‟ broom appearance.
IV. Unpleasant flavour.
Transmitted byAster leafhopper, Macrosteles quadrilineatus.

18. RICE YELLOW DWARF
Rice yellow dwarf (RYD) and rice orange leaf (ROL) are the major
phytoplasma diseases associated with rice (Arocha and Jones, 2010)
Reported in India in 1976 (Muniyappa and Ramakrishna).
SYMPTOMS :
I. Stunted and yellowish green to whitish green leaves.
II. Excessive tillering and leaves became soft and droop slightly.
III. Root growth is reduced significantly.
IV. Chlorosis on the leaves.
Transmitted by Green Leafhopper(Nephotettix virescens).

19. LITTLE LEAF OF BRINJAL
SYMPTOMS :
The symptoms in eggplant appeared 1-2 months after sprouting
(Rao and Kumar, 2017).
I. Reduction in leaf size and gives a rosette or bush
appearance.
II. shoot proliferation, stunted growth and phyllody occurs.
III. Nodes and internodes reduces in size or shortened.
IV. Affected plants do not bear fruit or sometimes small, hard
and tough.
V. Leaves starts yellowing due to marked reduction in total
chlorophyll and phenolic content in the phytoplasma
infected eggplant leaves.
Transmitted by Leafhoppers (Hishimonus phycitis).This is also
reported to be transmitted to tomato, potato, and tobacco by
dodder.

20. SANDAL SPIKE
First reported from Coorg district of Karnataka state.
SYMPTOMS :
Two types of symptoms are produced.
I. Rosette spike that is characterized by severe reduction of
leaf size and internodes and leaves become crowded.
II. The disease also results in phyllody of flowers with leaf-like
enlargement of the pistil.
III. Pendulous spike.
IV. The affected tree is killed within two or three years (Sen
Sarma, 1981).
Transmission through grafting, insect vectors, dodder etc.
leaf hopper vectors (Ghosh et al., 1985) - Moonia alhimaculata,
Nephotettix virescences and Redarator bimaculatus.

21. WITCHES’ BROOM OF BAMBOO
I. Yadav et al. (2016) identified „Ca. P. aurantifolia‟ associated with a witches‟ broom
disease of D. strictus.
II. Suryanarayana et al., 2009 reported symptoms of witches‟ broom disease on D.
strictus from Karnataka, India through virtual RFLP pattern of 16S rDNA
sequences and affiliate the detected phytoplasma with 16SrII-C subgroup.
SYMPTOMS :
I. Witches broom.
II. Severe proliferative branching at nodal region.
III. Reduction in leaf size.

22. WITCHES’
BROOM OF
BAMBOO
PHYTOPLASMA SYMPTOMS IN BAMBOO PLANTS IN INDIA

23. LETHAL YELLOWING
OF COCONUT
Phytoplasma diseases reported are root (wilt) disease
(RWD) and tatipaka disease (TD) of coconut, yellow leaf
disease of areca nut (YLD), spear rot disease of oil palm
(SRD) and oil palm stunting (OPS).
Present in Florida, Texas, Mexico and west Africa.
SYMPTOMS :
I. Premature drop of coconuts.
II. Inflorescence with blackened tips, almost all male flowers are dead and
black and sets no fruit.
III. Yellowing of leaves from older to younger.
IV. Finally, entire top of palm falls away leaving the tall trunk look like a
telephone pole.
Transmitted by Haplaxius crudus, Proutista moesta .

24. LETHAL
YELLOWING
OF COCONUT
PHYTOPLASMA SYMPTOMS LIKE (A & B) ROOT WILT, (C & D) YELLOWING OF
CROWN LEAVES AND (E) EARLY CHLOROSIS IN COCONUT, ARECANUT AND
OIL PALMS IN INDIA
(a) (b) (c)
(d) (e)

25. GRAPEVINE YELLOW
Occurs mostly in in Europe, Israel, Australia and North
America .
SYMPTOMS:
I. The leaves are thicker, brittle, rolled downward and show
veinal yellowing followed by necrosis.
II. Shoots show rows of black pustules that develop along the
internodes.
III. Flowers become whiter and desiccated.
Transmitted by Scaphoideus titanus.

26. CHICKPEA PHYLLODY
Gram or Chickpea phyllody disease was first reported in 1959
from Coimbatore in Tamil Nadu, India.
SYMPTOMS :
I. Phyllody means transformation of floral parts into green
leaf-like structures.
II. If infection occurs early, pods are not produced after the onset
of infection .
III. Infected plants are commonly stunted and bushy in
appearance and remain green .

27. TOMATO BIG BUD
It also affects onion, carrots, celery, lettuce, spinach, and parsley.
SYMPTOMS :
I. Swollen green buds that are typically large.
II. Don‟t set fruits and stems of affected plants are thick and
shows upright growth.
III. And foliage becomes distorted and yellow.
IV. Aerial roots may appear on the stems and the whole plant gives a bushy appearance due to
shortened internodes and stunted leaves.

28. MINOR DISEASES OTHER IN CROPS
I. POTATO - Garg et al. (1989) described the presence of MLO in potato affected by
marginal leaf chlorosis.
II. CHILLI - During winter 2004, an aster yellows phytoplasma was identified in chilli in
the Bahraich, UP with a low disease incidence (5%). The symptoms consisted of
shortening of leaves, petioles, internodes, rosetting and stunting (Khan and Raj, 2006).
III. ONION - Goel et al. (2017) confirmed the association of 2 phytoplasma groups (16SrXI
and 16SrIX) in onion with leaf yellows and in garlic with a decline disease from two
major onion/garlic growing states - Maharashtra and UP.
IV. PAPAYA - Two phytoplasmas were identified: a „Ca. P. asteris‟ - related strain associated
with dieback in UP (Rao et al., 2011) and a „Ca. P. aurantifolia‟ - related strain
associated with axillary shoot proliferation in Pune (Verma et al., 2012).
VI. CITRUS - Ghosh et al. (2017) reported witches‟ broom disease of acid lime. The
symptoms associated were small chlorotic leaves, highly proliferating shoots, and
shortened internodes. In advanced stages, infected branches showed dieback symptoms.

29. VII. PIGEONPEA - Pigeon pea plants showing little leaves, shortening of internodes and
petioles giving a bunchy appearance and stunting at Lucknow, UP were identified as
infected with „Ca. P. asteris‟ and „Ca. P. phoenicium‟ - related strains (Raj et al.,
2006; Rao et al., 2017). The disease symptoms characterized by little leaf, phyllody,
stunting and branch proliferation were observed during a field survey in 2016 in
cowpea, French bean in Akola and Pune region of Maharashtra (Thorat et al., 2016).
VIII.MUNGBEAN - Mungbeans exhibited symptoms of typical phytoplasma infection,
including stunting, extensive proliferation of branches, reduction in leaf size,
phyllody, and longitudinal splitting of green pods followed by germination of green
seeds. The associated phytoplasmas were identified as 16SrII-D subgroup „Ca. P.
aurantifolia‟.
IX. ROOT WILT OF COCONUT - Yellowing is restricted from the leaf tips to the middle
of the leaves. Necrosis of leaflets, deterioration, decay of root system, abnormal
shedding of buttons and immature nuts can be observed. The most consistent and
diagnostic symptom of the disease is the characteristic bending of leaflets
(flaccidity), foliar yellowing and marginal necrosis of the older leaves.

30. X. RICE - RICE ORANGE LEAF –
I. Recently, association of „Ca. P. asteris‟ with ROL disease in South India was confirmed
(Valarmathi et al., 2013). A regular occurrence of ROL disease was recorded in many
rice fields of varieties ADT 43, CO 39, White pone and BPT 5204 at Coimbatore and
Erode, Tamil Nadu.
II. The major symptoms recorded in rice varieties are typical orange, yellow discoloured
leaves distributed sporadically in the field but usually more concentrated on the borders.
III. The zigzag leafhopper (Recilia dorsalis) was reported as a vector of the ROL disease
associated phytoplasma (Valarmathi et al., 2013).
XI. WHEAT - The presence of 16SrXI-B subgroup phytoplasmas was detected in samples
from plants showing chlorosis with streak symptoms, yellowing and stunting of
durum and bread wheat genotypes (30 to 45 days old wheat, seedlings) at the Regional
Station of ICAR- IARI, Indore, India during 2013-2016. The disease severity was
greater in durum wheat (1.7-20% incidence) compared to bread wheat (1.3 and 10.4%
respectively). The symptomatic plants did not bear tassel at all or bear small deformed
tassel without grains.

31. OTHER
HORTICULTURAL
CROPS
SYMPTOMS IN (A) WITCHES’ BROOM IN LICHI ; (B) FLAT STEM AND WITCHES’ BROOM IN SAPOTA ; (C) LITTLE LEAF DISEASE IN BRINJAL ; (D) WITCHES’ BROOM
IN CUCURBITA PEPO ; (E) FLAT STEM IN LETTUCE (16SRVI-D); (F) WITCHES’ BROOM IN LENTIL ; (G) WITCHES’ BROOM IN CHILI ; (H) LITTLE LEAF IN
CATHARANTHUS ROSEUS ; (I) PHYLLODY IN HIBISCUS ROSA CHINENSIS ; (J) BUD PROLIFERATION IN ROSE ; (K) VIRESCENCE IN ROSE ; (L) WITCHES’ BROOM
IN CELOSIA ARGENTEA ; (M) CHRYSANTHEMUM PHYLLODY ; (N) MARIGOLD STUNTING ; (O) PHLOX YELLOWING AND LITTLE LEAF .
(a) (b) (c)
(d) (e) (f)
(h) (i)
(g)
(j) (k)
(l) (m) (n) (o)

32. (A) PHYTOPLASMA SYMPTOMS IN RICE SHOWING LEAF YELLOWING AT
COIMBATORE (16SRXI-B SUBGROUP);
(B)MAIZE LEAF REDNESS DISEASE (16SRI-B SUBGROUP) AT RAJOURI
DISTRICT, JAMMU; (C AND D) WHEAT SHOWING DWARFING, UNSPECIFIC
STUNTING SYMPTOMS AND LEAF YELLOWING.
(a) (b)
(c) (d)
WHEAT & MAIZE

33. Mixed infections of phytoplasmas and viruses have been reported in a wide range of plant
species indicating that both the pathogens can infect the same plant host and cause
significant losses.
I. The coexistence of 16SrVI phytoplasma, and begomovirus in eggplant showing
yellow disease symptoms was detected by Singh et al. (2015) from Meerut, India.
II. Kumar et al. (2016) reported mixed infection of Potato virus X and Potato virus Y
along with phytoplasma of the 16SrVI group associated with little leaf and mosaic
mottling disease in two eggplant varieties (Pusa Shyamla and Pusa Purple cluster).
III. Mixed infection of Sugarcane yellow leaf virus (SCYLV) and sugarcane grassy
shoot phytoplasmas (SCGS) were detected in 7 commercial sugarcane varieties
grown in Maharajganj and Shahjahanpur districts, UP.
MIXED INFECTIONS

34. IV. The presence of mixed infection in the pineapple disease and sugarcane grassy shoot
phytoplasma was detected in 4% of traditional sugarcane varieties at Shahjhanpur,
UP.
V. Papaya plants at Pune, Maharashtra were reported by Verma et al. (2014) exhibiting
symptoms of multiple axillary shoots, leaf reduction, mosaic, chlorosis, flattened
petiole and virescence of flowers. The plants resulted infected by Papaya ringspot
virus (PRSV) and „Ca. P. aurantifolia‟.
VI. Symptoms associated with the tomato leaf curl disease in tomato fields from
Southern Karnataka was identified to be associated with a phytoplasma member of
group 16SrII, „Ca. P. australasia‟- related strain and Tomato leaf curl New Delhi
virus (ToLCNDV) (Swarnalatha and Reddy, 2014).

35. I. Discovery and research of mycoplasmas proved difficult due to their incredibly small
size, difficulty in staining and the challenging laboratory conditions necessary to
successfully culture them. Being so minute in size they were not initially identified as
bacteria and were considered viruses for years. Later mycoplasmas were confused with
the L-forms, which are bacteria that have lost their cell walls either completely or
partially.
II. In India, the detection of phytoplasmas was initially based on microscopic methods
including transmission electron microscopy (TEM), light microscopy and DAPI (DNA-
specific-6-diaminido-2-phenylindole) fluorescence microscopy technique (Deeley et al.,
1979; Purohit et al., 1978; Manimekalai et al., 2016). Serological and molecular
diagnostic techniques emerged in early 2000s (Viswanathan 2001).
III. PCR-based methods (1990) are more sensitive than ELISA and RFLP analysis and
allowed the identification of different phytoplasma strains. However, the inability to
culture phytoplasma in vitro, their low concentrations, and uneven distribution in the
host plant were making their detection tricky.
DETECTION OF DISEASES

36. IV. Universal phytoplasma group-specific primers have been developed and used for
amplification of 16S rRNA and 23S rRNA, and 3F/3R amplified ~ 1300 bp and
IF7/7R2 amplified ~ 490 bp product in direct or nested PCR assays (Manimekalai et
al., 2010).
V. New sets of multilocus gene primers for gyrA , gyrB and dnaB were designed and
developed for amplification of phytoplasmas belonging to 16SrI,-II,-VI and -XI groups
(Madhupriya et al., 2015).
VI. The application of PCR to the detection of phytoplasmas in diseased plants and possible
insect vectors has significantly facilitated the identification of a wide array of
phytoplasmas in different plants species in India.
These can be detected by the manifestation of symptoms, transmission using dodder and
insect vectors, indirect evidence of positive response to tetracycline antibiotics, Dienes‟
stain, transmission electron microscopy, light microscopy by using DAPI, enzyme-linked
immunoassay and nested PCR assay.

37. No effective control measures of the phytoplasma diseases associated with these crops are
developed so far, but for their successful management these can steps be followed –
I. The incidence of the disease could be reduced by roughing symptomatic plants in
brinjal little leaf and spraying insecticides and by Using healthy, certified disease free
sugarcane setts, uprooting of infected plants, hot water treatment of setts at 52˚C for
30 min. and avoiding ratooning in sugarcane grassy shoot.
II. Selection and screening of genotypes resistant to phytoplasma infection and
treatment with tetracycline to checks the diseases is effective management strategy.
III. Eradication of perennial weeds host that harbour the phytoplasma in case of phyllody,
aster yellows. Avoid alternate host of insect vectors growing near the host crops.
IV. Management of insect vectors by altering the dates of sowing to avoid peaks of insect
vector populations, along with spraying insecticides like imidachlorprid helps in
minimizing the phytoplasma disease incidence in the fields.
MANAGEMENT

38. THANK YOU
AS FOR ME , ALL I KNOW IS THAT I
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