Maize Genomics and Genetics 2015, Vol.6, No.1, 1-5
2
maize hybrids in the state has increased the incidence
of different diseases. Hence, the present study was
undertaken to identify the hybrids against leaf blight
and brown spot diseases of maize.
Results and Discussion
The parent and hybrids of maize in present
investigation were also evaluated under natural
epiphytotic conditions during 2004 and 2005 for
reaction to leaf blight (
Helminthosporium maydis
and
H. turcicum
) and brown spot (
physoderma zea
maydis
) (Table 1).
Table 1 Pooled data of reaction of parents and maize hybrids to leaf blight and brown spot during 2004 as well as 2005
Diseases
Score
Reaction
Parents
Hybrids
0
Highly
resistant
_
_
1
Resistant
Line-3, line-8, line-10
and line-18
line-3×Early composite, line-5×Early composite, line-10×Early
composite, line-13×Early composite, line-15×Early composite,
line-19×Early composite, line-18×Girija, line-5×KH-2001 ,
line-18×KH-2001 and line-19×KH-2001.
2
Moderately
resistant
Line-4, line-6, line-7,
line-12 and line-16
Line-14×Early composite, line-22×Girija, line-14×KH-2001 and
line-22×KH-2001.
3
Moderately
susceptible
_
Line-23×Early composite, line-6×Girija, line-13×Girija,
line-20×Girija, line-24x Girija, line-10×KH-2001,
line-12×KH-2001, line-13×KH-2001, line-21×KH-2001 and
line-23×KH-2001.
4
Susceptible
_
_
5
Highly
susceptible
_
_
Note: Scale used 0-5 (Chenulu and Hora, 1962)
Performance of Parents
The parents
viz.,
Line-1, 3, 5, 8, 10, 13, 17, 18, 20,
21, 24 indicated slight leaf blight infection during
2004 as well as 2005. The line-3, 8, 9, 10, 15, 18,
22 had slight brown spot infections during 2004
and 2005.
The parents
viz.,
line-2, 4, 6, 7, 9, 12, 14, 15, 16
were observed light infection during 2004 and
2005; line-1, 4, 5, 6, 7, 11, 12, 13, 20, 21, 24
showed light infection for brown spot diseases.
Remaining lines did not behave consistently during
2004 and 2005 for slight or light infection in
respect to diseases for leaf blight or brown spot
vice-versa.
Cross combinations resistant to leaf blight
The cross combinations
viz.,
Line-1×Early
composite, Line-3×Early composite, Line-5×Early
composite, Line-7×Early composite, Line-10×Early com-
posite, Line-13×Early composite, Line-15×Early compo-
site, Line-19×Early composite, Line-24×Early composite,
Line-5×Girija, Line-11×Girija, Line-14×Girija, Line-15×
Girija, Line-23×Girija, Line-4×KH-2001, Line-5×KH-
2001, Line-8×KH-2001, Line-18×KH-2001 and Line-19×
KH-2001 showed resistant for leaf blight during
2004 and 2005. Similar results were also reported
for leaf blight by Ishfaq et al. (2014).
Cross combinations resistant to brown spot
The cross combinations were observed resistant for
brown spot
viz.,
Line-3×Early composite, Line-4×
Early composite, Line-5×Early composite, Line-10×
Early composite, Line-13×Early composite, Line-19×
