18. TT Province
Total infected area (ha) Total destroyed
area (ha)Total Light Medium High
1 Tay Ninh 25,064.4 16,550.0 4,184.2 4,33.2 143.2
2 Binh Phuoc 320.0 240.0 80.0 0.0 -
3 Binh Duong 1,828.5 481.0 786.5 561.0 -
4 Ba Ria-Vung Tau 31.0 31.0 0.0 0.0 -
5 Ho Chi Minh 40.2 40.2 0.0 0.0 -
6 Long An 234.0 170.0 17.0 47.0 5.0
7 An Giang 15.3 15.3 0.0 0.0 -
8 Đong Nai 616.7 580.4 32.0 4.3 42.4
9 Phu Yen 615.7 136.5 244.4 234.8 25.2
10 Ninh Thuan 223.1 134.1 83.0 6.0 31.6
11 Binh Thuan 370.0 15.0 213.0 142.0 -
12 Gia Lai 1,817.8 1.376.4 423.0 18.4 73.8
13 Kon Tum 365.0 290.0 56.0 20.0 -
14 Đak Lak 394.5 110.5 7.0 277.0 -
15 Ha Tinh 170.3 170.3 0.0 0.0 -
16 Quang Ngai - - - - -
Total 31,865.5 20,100.7 6,144.1 5,620.7 321.2
Total of CMV-infected growing area (ha) (10/9/2019)
19. Effect of SLCMV on cassava yield in Tay Ninh province, 2019
Variety
On yield On starch content On stalk and leaves yield
Yield
(tons/ha)
Reduction
percentage (%)
Starch content
Reduction
percentage (%)
Stalk and leaves
yield (tons/ha)
Reduction
percentage (%)
Healthy HL-S11
15.30-24.53 1.02-7.30 5.88-39.14
SLCMV- HL-S11
Healthy KM94
12.65-19.23 2.48-18.97 14.48-37.68
SLCMV- KM94
Healthy KM419
15.08-34.55 4.49-8.94 3.62-38.97
SLCMV- KM419
Healthy KM140
22.74-45.74 5.69-10.16 8.66-45.65
SLCMV- KM140
20. IDENTIFICATION OF BIOTYPES OF WHITEFLY (B. TABACI)
BY NUCLEOTIDE SEQUENCE OF ITS MITOCHONDRIAL COX1
GENE
21. Begomoviruses are transmitted from plant to plant only by the vector
whitefly Bemisia tabaci
1 mm
Bemisia tabaci Med
The mode of transmission is
● circulative,
● non-replicative
transmission
23. Bemisia tabaci Asia II 1
The whitefly Bemisia tabaci has long been considered
one species composed of several biotypes, but now it is reclassified as a
complex of at least 24 species
Bemisia tabaci New World
Bemisia tabaci Mediterranean
current classification
Bemisia tabaci Middle-East Asia Minor1
species
Bemisia tabaci
species
Bemisia tabaci Asia 1
biotypes
biotype H
biotype M
biotype K
biotype P
biotype A
biotype C
biotype Q
biotype J
biotype B
Former classification
Viet Nam
29. 1 8 12 15 16 17
CMBRep/F-ACMVRep-EACMVRep/R
M 19 29 NC
Samples:
+ From 1-29: Cassava leaves collected
from Tay Ninh in 2018
+ NC: Negative control (Healthy leaf)
CONFIRMATION THE PRESENCE OF ACMV AND EACMV FROM CASSAVA SAMPLES
COLLECTED FROM TAY NINH PROVINCE WITH MORE SPECIFIC PRIMER PAIRS
500 bp
300 bp
700 bp
32. LAMP procedure
• Break the leaf surface with a wooden toothpick
• Wash the toothpick in a reaction mixture
• Keep the tube in hot water for 30 min
• Observe by bare eyes or under UV
33. Labor: Easy Laborious
Time: Fast Slow
Sensitivity: High Thấp/Low
Cost: Inexpensive Expensive
On-site: Yes No
LAMP to detect genome DNA
34. Detection of DNA by loop-mediated isothermal
amplification (LAMP)
Negative: No florescence Positive:
Greenfluorescence
35. Merit of LAMP
cutting from a diseased
plant
cutting from a healthy
plant
(ii) On-site diagnosis also for cuttings
36. PCR vs LAMP
PCR LAMP (dried kit)
sensitivity very high extremely high
primers two four or six
polymerase Taq (kept in –20℃) Bst (dried)
temperature
92oC
55oC (Cycling)
72oC
60-68℃ (one temp)
detection electrophoresis eyes (light or UV)
37. PCR LAMP (dried kit)
sensitivity very high extremely high
primers two four or six
polymerase Taq (kept in –20℃) Bst (dried)
temperature
92oC
55oC (Cycling)
72oC
60-68℃ (one temp)
detection electrophoresis eyes (light or UV)
PCR vs LAMP
DNA extraction by a
centrifuge is NOT
needed
-20℃ freezer is NOT
needed
Thermal cycler is NOT
needed
Electrophoresis
apparatus is NOT
needed