GSD-Grassy Shoot Disease of Sugarcane.pdf

Its all about Grassy Shoot Disease of Sugarcane With its Causal organism, Symptoms, Disease cycle and Management.

1. z
Prof. Shubhangi Pradeep Patil,
Department of Botany,
Miraj Mahavidyalaya, Miraj
Grassy Shoot Disease of Sugarcane

2. z
▪Host-Saccharum officinarum (Sugarcane)
▪Causal Organism: Phytoplasma

3. zOccurrence:
▪Grassy Shoot disease is one of the most
important diseases caused by Phytoplasma and
affecting sugarcane crop throughout its crop
growth stages. It is observed in many states of
India. This disease causes severe damage to the
ratoon crop.

4. zSymptoms:
▪Initial symptom appears in the young crop of 3 –
4 months age as thin papery white young leaves
at the top of the cane.
▪Later, white or yellow tillers appear in large
number below these leaves (profuse tillering).
▪The cane becomes stunted with reduced
internodal length with axillary bud sprouting.
▪This disease appears in isolated clumps.

5. z
Symptoms:
Whitening of leaf Profuse Tillering
Reduced Internodal Length Grassy Shoot

6. z
Causal Organism:
▪Phytoplasmas are obligate intracellular
parasites of plant phloem tissue and of the
insect vectors that are involved in their plant-
to-plant transmission. Phytoplasmas were
discovered in 1967 by Japanese scientists
who termed them mycoplasma-like
organisms.

7. zDisease cycle
▪The primary spread of the phytoplasma is
through diseased setts and cutting knifes. The
pathogen is transmitted secondarily by aphids
viz., Rhopalosiphum maydis, Melanaphis
sacchari and M. idiosacchari. Sorghum and
maize serves as natural collateral hosts.
Rhopalosiphum maydis
Melanaphis sacchari

8. zControl Measures/ Disease Management
Culturalmethod:
•Growingresistantvarietiesviz.,Co86249,CoG93076andCoC22
•AvoidratooningifGrassyShootDiseaseincidenceismorethan15%inthe
plantcrop
•Ifdiseasesymptomsarevisiblewithintwoweeksafterplanting,suchplantscan
bereplacedbyhealthyplants.
•Uprootedinfectedplantsneedtodisposedofbyburningthem.
Physicalmethod:
•Rogueoutinfectedplantsinthesecondaryandcommercialseednursery.
•Treatthesettswithaeratedsteamat50°Cfor1hourtocontrolprimaryinfection.
•Treatingthemwithhotairat540Cfor8hoursandsprayingtwiceamonthwith
aphidicides.
Chemicalmethod
•Spraydimethoate@1mlin1litreofwatertocontrolinsectvector
•Applypesticidemethyl-demeton@2ml/litofwaterforcontrollingaphids.

9. z
Thankyou