EVALUATION OF SOME RAPESEED AND MUSTARD GENOTYPES FOR RESISTANCE TO WHITE RUST D1SEASE 	CAUSED BY Albugo candida

Draz,, Eetmad E.; Abo-Ghazala, M. E.

doi:10.21608/jpp.2005.237467

EVALUATION OF SOME RAPESEED AND MUSTARD GENOTYPES FOR RESISTANCE TO WHITE RUST D1SEASE CAUSED BY Albugo candida

Document Type : Original Article

Authors

Eetmad E. Draz, ¹
M. E. Abo-Ghazala ²

¹ Plant Pathology Research Institute, ARC. Egypt

² Field Crops Research Institute, ARC, Egypt

10.21608/jpp.2005.237467

Abstract

One hundred and six Brassica genotypes of four species i.e. B. nap us, B.
juncea, B. campestris, B. carinala were evaluated tor resistance to white rust (caused
by Albugo candida) at seedling stage under controlled conditions (in greenhouse.
unde~ artificial epiphy1o\ic conditions) and at adult stage under natural conditions,
during the two successive growing seasons 2002103 and 2003104 in the experimental
farm 01 Sakha Agricultural Research Station, Kafr EI-Sheikh, Egypt. At seedling stage,
all B. napus lines (55 lines). 4 lines (B. campestris) and 3 lines (B. carinala) were
completely resistant. Four lines of B. juncea were moderately resistant. while twenty
lines or both B. juncea and B. cempesiris were moderately susceptible. The rest of the
tested lines (B. juncea) were susceptible.
At adult stage, the results showed that 60 lines of B. nap < /em>us,B. camp < /em>eslris and
B. cetinets were free from disease during the two growing seasons. whereas 6 lines
of B. juncea and 4 lines of B. cemp < /em>estris exhibited resistance or moderate resistance
response during the two seasons. Thirteen lines were moderately susceptible during
2002/03 and eight lines during 2003/04. The rest 01 the tested lines were susceptible
or highly susceptible during the two seasons. The obtained results also showed that.
the most susceptible lines had similar consistent percent of disease severity, in
general, Ihrough the two growing seasons.
Ten lines of B. juncea were used to study the occurrence and development of
while rust disease under natural field conditions. The results indicated thai, almost all
of the tested lines gave high reaction (local infec1ion, as pustules on leaves). As
regard to systemic infection (Slag-head formations), the obtained results indicated that
the highest values of stag-head/piant were recorded with line i.e.B. juncea Int. 233that
showed severe infection with the disease progress, followed by lines I.e. Int. 239 and
\1'\\. 234 that exhibited moderate infection; lines Le. Int. 333. Int. 160 and Int. 151 thai
showed slight Infection. While, lines i.e. Int. 176, Int. 237 and Int. 246 remained free
from symptoms (stag-head formations) although it had localized pustules on leaves.
In general, the present wor1( would be of a great importance and fruitfull tool in
screening and evaluating canota crop against while rust disease.