PNABD246.pdf

cv. H-70-3 had the least incidence. The loss in yield ranged from 2.12 to
93.18% in mungbean and 2.82 to 95.17% in blackgram. The symptoms were most
conspicuous when the temperature was around 25 to 35 C and the relatve humidity
higher than 70% in the morning and 50% in tihe evening. The virus was readily
transmitted through Aphis craccivora and A. gossypii in a non-persistent
manner. Seed transmission was aroud 21/. The host range was not restricted to
leguminous plants. The virus had a dilution end point between I.OE-3 and
1.OE-4, thermal inactivation point between 64 and 66 C and longevity in vitro
of 3 days at room temperature and 9 days at refrigerator temperature. The virus
was purified by chloroform: butanol (1:1) treatment and precipitation with 8%
PEIG plus 1.2% NaCI. The virus had spherical particles with an average diameter
of about 50 nm and containing 15.244 nucleic acid. This virus has similarities
with pea enation mosaic virus. Out of 390 varieties of mungbean and 138
varieties of blackgram screened for resistance, none was found highly
resistant, but mungbean varieties L-24-2 and 15227 and blackgram varieties DLU
90 and DLU 487 were resistant. There was an appreciable reduction in seed
transmission of the virus when seeds were heat treated. Out of 7 insecticides
tested in the field, phosphamidon (0.035% a.i.) was found most effective when
sprayed on plants 10 days and 25 days after sowing. The combination of seed
heat treatment and 2 foliar sprays of phosphamidon (0.035% a.i.) were found
most effective in controlling vectored spread of the disease. [AS/EMS]
*0214 Dhingra, K.L. ; Chenulu, V.V. 1981. Studies on the transmission of
urid leaf crinkle and chickpea leaf reduction viruses by Aphis craccivora Koch.
INDIAN PHYTOPATHOLOGY, v.34(I):38-42. [En] [En Abstj (A:PS)
Myzus persicae (Sulz.) was found to be an additional vector of blackgram
leaf crinkle virus (BLCV). The relationship of BLCV and chickpea leaf reduction
virus (CpLRV) with A. craccivora was worked out in details. Preacquisition
starvation of the vector resulted in appreciable increase in the percentage of
transmission of both the viruses. Maximum percentage of transmission was
obtained through the optimum combination of 10 aphids per test plant which has
been allowed acquisition access for 30 seconds, preceded by preacquisition
fasting of 2 hours in the case of CpLRV and 4 hours for BLCV. That these
viruses are non persistently borne is further evidenced by the fact that the
vector lost infectivity within 10 and 30 minutes in the cases of BLCV and
CpLRV, respectively. A 'tapping' aphid inoculation technique was found superior
to conventional brush inoculation for virus transmission. [ASJ
*0215 Bhaktavatsalam, G. ; Nene, Y.L. ; Beniwal, S.P.S. 1982. Hyperauxiny
in urdbean leaves infected by urdbean leaf crinkle virus. INDIAN
PHYTOPATHOLOGY, v.35(4):b83-b85. [En] (A:PS)
The increase in IAA content in blackgram leaf crinkle virus infected leaves
of blackgram suggests that IAA might be involved in leaf expansion, which is
one of the symptoms induced by the disease. [EMSJ
*0216 Bhardwaj, S.V. ; Dubey, G.S. ; Sharma, I. 1982. Effect of benlate on
infection and transmission of urdbean (Vigna radiata var. Hungo) leaf crinkle
uirus. JOURNAL OF PHYTOPATHOLOGY, v.105(1):87-91. [En] [En De Abstj kA:PS)
Blackgram plants (Vigna mungo Hepper) drenched with benlate solution (1%
and higher concentrations) before inoculation with blackgram leaf crinkle virus
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