PNABD246.pdf

*0161 Nair, N.G. ; Nene, Y.L. 1973. Studies on the yellow mosaic of urd
bean (Phaseolus mungo L.) caused by mung bean yellow mosaic virus. 2.
Virus-vector relationships. INDIAN JOURNAL OF FARM SCIENCE, v.1(1):62-70.
[En] [En Abst! (REP.MB-0946)
Acquisition and inoculation of mungbean yellow mosaic virus (MYMV) by the
whitefly (Bemisia tabaci Gen.) took place with a minimum feeding period of 15
minutes each. Pre-acquisition starvation increased the transmission efficiency.
MYMV was found to have a definite incubation period of more than three hours in
the whitefly. The severity of the disease was the same irrespective of the
number of insects used in transmission. The virus was retained by the vector
until its death in 10 days. However, the percentage transmission decreased with
the increase in the period of retention indicating that MYMV is a typical
circulative virus. (AS/THH]
*0162 Nair, N.G. ; Nene, Y.L. ; Naresh, J.S. 1974. Reaction of certain urd
bean varieties to yellow mosaic virus of mung bean. INDIAN PHYTOPATHOLOGY,
v.27:256-257. [En] (REP.MB-0524)
Both necrotic mottle and yellow mottle are host reactions to the same
disease, mungbean yellow mosaic virus. The varieties showing necrotic mottle
gave higher yield and were less severely affected than those which showed
yellow mottle symptoms. It is concluded that necrotic mottle is a type of
resistant reaction to MYMV. [EMS]
*0163 Nair, N.G. ; Nene, Y.L. 1974. Studies on the yellow mosaic of urd
bean (Phaseolus mungo L.) caused by mung bean yellow mosaic virus. 3. Factors
influencing transmission and symptom expression. INDIAN JOURNAL OF FARM
SCIENCE, v.2:42-47. [EnJ [En AbstJ (REP.MB-0947)
Keeping test seedings 24 hour and 48 hour before and after inoculation with
mungbean yellow mosaic virus (MYMV) did not produce any significant difference
in the percentage of transmission. Similar was the case with the inoculation at
various stages of growth. Moreover, it was found that the cell sap acidity of
various blackgram varieties is not involved in their resistance to MYMV. Both
the percentage of transmission of MYMV in blackgram as well as the incubation
period of the virus in the test seedings were influenced by seasonal
variations. During November and December the percentage of transmission was
reduced and incubation period was extended compared to months from July through
October. [AS]
*0164 Nair, N.G. ; Nene, Y.L. 1974. Studies on the yellow mosaic of urd
bean (Phaseolus mungo L.) caused by mung bean yellow mosaic virus. 4. Nature
and extent of losses due to infection at various stages of growth. INDIAN
JOURNAL OF FARM SCIENCE, v.2:48-50. [En] [En AbstJ (REP.MB-0948)
Inoculations of blackgram plants at various stages of growth affected the
yield considerably. Infection upto an age of three weeks resulted in the
complete loss of seed yield. There were no significant differences in the yield
between healthy plants and those inoculated at the eighth week or later. The
main factor responsible for the reduction in yield was found to be the
reduction in the number of pods produced per plant as a result of MYMV
infection and not in the number of seeds per pod. It was also observed that the
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