Maize
Genetics Cooperation Newsletter vol 84 2010
Please
Note: Notes submitted to the Maize Genetics Cooperation Newsletter may be cited
only with consent of authors.
Studies on Character Association in
Winter Maize under Normal and Excess Soil Moisture (ESM) Conditions
K. D Research Station, Sher-e-Kashmir University of
Agricultural Sciences & Technology Shalimar, Kashmir, J & K, India
*Deptt of Genetics & Plant Breeding,
College of Post Graduate Studies, GBPUA&T, Pantnagar India
Correspondence author: [email protected]
A
set of forty-five genotypes including five parents, their F1�s, F2�s
and backcross generation of maize differing in their reaction to ESM conditions
were used for estimating inter-character correlations between different
morphological traits, planted during winter season. The knowledge of the
relationships among various traits affecting grain yield is imperative to
arrive at potentially affecting selection index because the efficacy of
selection process is greatly enhanced by using appropriate selection indices
Estimates of genotypic correlation coefficient were generally higher than
phenotypic correlations coefficients in the both environments.
Key words: Correlation, maize
The
ultimate aim of a breeding programme is to evolve superior genotypes by
exploiting the available genetic variability from the broad array of breeding
material. Crop yield is a complex character governed by several interacting
intrinsic and extrinsic factors. Most of the yield components are less complex,
simply inherited and less influenced by the environmental deviations.
Therefore, Grafius (1956) suggested that selection based on component
characters is more effective than on yield per se. The appropriate knowledge of
such interrelationships between grain yield and its contributing components can
significantly improve the efficiency of breeding programmes through the use of
appropriate selection indices (Mohammadia et al., 2003). To end up with superior genotypes, the
knowledge of interrelationship of yield and yield related traits in a
particular situation is a prerequisite. The extent of relationship between the
important traits in given conditions can be studied by correlation coefficients
and will aid in developing suitable selection criterion in order to choose
suitable breeding procedure for developing cultivars suitable for wide range of
environments. The excess soil moisture (ESM) is becoming threat to maize crop
as 15 per cent of the total maize growing area is affected by floods and
waterlogging problem in south-East Asia alone. In India about 25-30 per cent
loss of maize production occurs every year because of ESM stress (DMR, 2001).
The
experimental materials consisted of forty five genotypes of maize which
included five parents (three tolerant and two susceptible), their F1�s,
F2�s and backcrosses, grown during Rabi 2005-06 at Crop Research Centre of G.B. Pant
University of Agriculture and Technology, Pantnagar in randomized block design
with three replications. The experiments were laid down in two sets (one under
normal and the other under Excess Soil Moisture (ESM) conditions). Experimental
material was sown in two row plots of 5 meter length with row to row spacing of
75 cm and plant to plant distance of 25 cm. In ESM trial, waterlogging
treatment was given at knee high growth stage for 6 days, by keeping continuous
submergence with an average depth of ponding of about 5 cm. After 6 days of
ponding, water was drained out of the plots. Observations were recorded on days
to 50 per cent tasseling, days to 50 per cent silking, Anthesis Silking
Interval (ASI), plant height, ear height, cob length, cob diameter, leaf
temperature, SPAD value, Transpiration rate and Photosynthetically Active
Radiation (PAR) for evaluation of genotypes for intercharacter relationship.
The
correlations between all possible pairs of characters under study, at
genotypic, phenotypic and environmental levels were worked out from the
analysis of variance and covariance as suggested by Searle (1961).
In the present investigation, character
correlation coefficients estimated under normal and ESM trials of winter maize
are presented in the Tables 1 and 2 respectively. The interpretation of results
of character association among different morphological traits revealed
interesting correlations among different traits particularly under Excess Soil
Moisture (ESM) conditions. Under both sets of conditions, days to 50 per cent
tasseling and days to 50 per cent silking were positively and significantly
correlated with were each other both sets of conditions. An interesting
correlation observed between Anthesis Silking Interval (ASI) and nodes bearing
adventitious roots, as they were negatively and significantly correlated under
ESM condition at both genotypic (rg=-0.409) and phenotypic level (rp=-0.250).
This correlation under ESM conditions had practical implications as wider ASI
is indication of susceptibility to ESM conditions and further lower number
nodes bearing adventitious roots will add to the problem. It was noteworthy
that under ESM conditions ASI and yield were negatively and significantly
correlated with each other at both genotypic (rg =-0.175) and
phenotypic level (rp=-0.116) which is in conformation to the
findings of Zaidi et al (2003) and Ajaz
and Warsi (2006). Yield and 100 kernel weight were positively correlated under
both normal (rg = 0.237) and ESM conditions (rg=0.322).
Under ESM conditions yield and nodes bearing adventitious roots were having
positive correlation at both genotypic (rg=0.190) and phenotypic
level (rp=0.130), the same findings were also observed by Rathore et
al (1996) and Zaidi and Singh (2001).
Increased number of nodes bearing adventitious roots assists in avoiding
lodging of plants under ESM conditions which in turn results in increasing the
overall yields (Zaidi et al
2002). Yield under both normal and ESM conditions was found to be positively
correlated to SPAD values at both genotypic and phenotypic level. As higher
SPAD values revealed more greenness of leaves which in turn contributes in net
photosynthetic rates and subsequently higher yields. Also yield was found to be
positively correlated to cob length and cob diameter under both sets of
conditions. Under ESM conditions yield and transpirations rates were positively
correlated (rg=0.179). It was observed that under ESM conditions
transpiration rates got reduced, so higher yields coupled with high transpiration
rates was evident. Plant height was positively correlated to yield under both
normal (rg =0.606) and ESM condition (rg = 0.267) whish
are in confirmation to the findings of Lizaso and Riche (1997) and Ajaz and
Warsi (2006).
Generally,
correlation coefficients at genotypic levels were similar in direction but of
higher magnitude than phenotypic correlation coefficient for most of the
intercharacter associations. This suggested the preponderance of environmental
factors which might have suppressed the expression of character association at
phenotypic level.
In
any breeding programme directed to improve the yield under ESM conditions it is
necessary to conduct experiments under both the conditions as selection for
yield under stress is much less efficient than under non-stress conditions
(Blum, 1988). Further due importance is to be given to the growth parameters
like ASI, nodes bearing adventitious roots and there interrelationships to the
yield.
Ajaz. A. Lone and M.Z.K.
Warsi (2006) Character association in maize under normal and excess soil
moisture (ESM) conditions in different environments. Pantnagar Journal of
Research. Vol.4 (2),
61-64, 2006
Blum, A. (1988). Plant
breeding for stress environments. CRC Press, Boca, Raton, F1.
DMR. (2001). Annual report,
Directorate of Maize Research (DMR). 49th Annual Maize Workshop, Directorate of Maize Research, held at
C.S. Azad University of Agriculture and Technology, Kanpur (U.P.), India, 5-9
April, 2001.
Grafius, J.E. 1956.
Components of yield in oats: A geometrical interpretation. Agron. J. 48: 419-423.
Lizaso, J.I. and Ritchie,
J.T. (1997). Maize shoots and root response to root zone saturation during
vegetative growth. Agron. J.
89: 125-134.
Mathur, R.K.; Lal, C.;
Bhatnagar, S.K.; Jain, and Gour, H.K. (1997). Effect of growing conditions on
character association in maize (Zea mays L.). Ann. Agric. Res. 18: 503-507.
Mohammadia, S.A., Prasanna,
B.M. and Singh, N.N. 2003. Sequential path model for determining
interrelationship among grain yield and related characters in maize. Crop
Sci 43: 1690-1697.
Rathore, T.R.; Warsi, M.Z.K.;
Lothrop, J.E. and Singh, N.N. 1996. Production of maize under excess soil
moisture conditions. 1st Asian Regional Maize Workshop, 10-12 Feb, 1996, P.A.U., Ludhiana. pp.
56-63.
Rathore, T.R.; Warsi, M.Z.K.;
Singh, N.N. and Vasal, S.K. (1998). Production of maize under excess soil
moisture conditions. 2nd Asian Regional Maize Workshop, PCCARD,
Los Banos, Philippines,
Feb. 23-27, 1998.
Searle, S.R. (1961).
Phenotypic, genotypic and environmental correlations. Biometrics. 17: 474-480.
Zaidi, P.H. and Singh, N.N.
(2001). Effect of water logging on growth, biochemical compositions and
reproduction in maize. J. Plant Biol. 28: 61-67.
Zaidi, P.H.; Rafique, S.;
Singh, N.N. (2003). Response of maize (Zea mays L.) genotypes to excess soil moisture
stress: morpho-physiological effects and basis for tolerance. European J.
Agron. 19(3): 383-399.
Zaidi, P.H.; Rafique, S.;
Singh, N.N. and Srinivasam, G.G. 2002. Excess soil moisture tolerance in maize
– progress and challenges. Proceeding of 8th Asian Regional
Maize Workshop, 5-9 Aug.
2002, Bangkok, Thailand.
Table
1: Genotypic, phenotypic and environmental correlation coefficients among
different characters under normal conditions in winter maize
Character
|
|
Days to 50%
silking |
ASI |
Plant height |
Ear height |
Nodes bearing
adventitious roots |
Yield
|
100 kernel weight |
Cob length |
Cob diameter |
Leaf temperature |
SPAD value |
Transpiration rate |
PAR |
Days to 50% tasseling |
G |
0.855** |
-0.260 |
0.224 |
-0.217 |
0.140 |
0.080 |
0.142 |
2.611 |
0.539** |
-0.192 |
-0.058 |
-0.251 |
-0.146 |
P |
0.742** |
-0.193 |
-0.119 |
-0.131 |
0.009 |
0.055 |
0.066 |
0.080 |
-0.089 |
-0.049 |
-0.037 |
-0.170 |
-0.084 |
|
|
E |
0.675** |
-0.169 |
-0.260 |
-0.101 |
-0.176 |
0.044 |
-0.074 |
-0.179 |
-0.237 |
-0.032 |
-0.019 |
-0.093 |
0.043 |
Days to 50% silking |
G |
|
0.245 |
0.392** |
-0.112 |
-0084 |
0.174 |
0.147 |
2.414 |
0.384** |
0.209 |
-0.220 |
-0.193 |
-0.068 |
P |
|
0.474** |
-0.049 |
-0.142 |
-0.107 |
0.075 |
0.104 |
0.107 |
-0.141 |
-0.118 |
-0.118 |
-0.194 |
-0.045 |
|
|
E |
|
0.577** |
-0.224 |
-0.157 |
-0.163 |
-0.194 |
0.803 |
-0.117 |
-0.263 |
-0.185 |
0.110 |
-0.238 |
-0.038 |
ASI |
G |
|
|
0.419** |
0.218 |
-0.410** |
0.324** |
-0.070 |
0.182 |
-0.307* |
0.962* |
-0.259 |
0.048 |
0.110 |
|
P |
|
|
0.081 |
-0.013 |
-0.193 |
0.099* |
0.015* |
0.044** |
-0.052 |
-0.076 |
-0.076 |
-0.067 |
0.046 |
|
E |
|
|
-0.012 |
-0.075 |
-0.053 |
-0.016 |
0.178 |
0.037 |
-0.002 |
-0.194 |
0.115 |
-0.204 |
-0.16 |
Plant height |
G |
|
|
|
0.558** |
0.012 |
0.606** |
0.462** |
1.968 |
0.426** |
1.263 |
0.103 |
-0.354* |
-0.219 |
|
P |
|
|
|
0.499** |
0.047 |
0.274 |
0.196 |
0.154 |
0.135* |
0.198 |
0.066 |
-0.096 |
-0.098 |
|
E |
|
|
|
0.484** |
0.098 |
0.007 |
-0024 |
0.035 |
0.072 |
0.093 |
0.130 |
0.107 |
0.015 |
Ear height |
G |
|
|
|
|
0.176 |
0.289 |
0.171 |
1.323 |
-0.370* |
0.678** |
-0.052 |
-0.209 |
0.120 |
|
P |
|
|
|
|
0.108 |
0.167 |
0.130 |
.180 |
0.217 |
0.142 |
-0.015 |
-0.096 |
0.028 |
|
E |
|
|
|
|
0.091 |
0.231 |
0.214 |
0.112 |
0.290 |
0.092 |
0.055 |
-0.033 |
0.187 |
Nodes bearing adventitious roots |
G |
|
|
|
|
|
-0.173 |
0.073 |
-0.717** |
0.225 |
1.033 |
0.216 |
-0.382** |
-0.209 |
P |
|
|
|
|
|
-0.146 |
0.046 |
-0.086* |
0.066 |
0.069 |
0.191 |
-0.321** |
-0.192 |
|
E |
|
|
|
|
|
0.032 |
-0.106 |
-0.001 |
-0.005 |
-0.246 |
0.051 |
-0.118 |
-0.169 |
|
Yield |
G |
|
|
|
|
|
|
0.237 |
0.680** |
0.286 |
0.672** |
0.246 |
0.006 |
-0.081 |
|
P |
|
|
|
|
|
|
0.222 |
0.114** |
0.129 |
0.185 |
0.236 |
-0.006 |
-0.078 |
|
E |
|
|
|
|
|
|
0.003 |
0.123 |
0.160 |
0.277 |
-0.062 |
-0.121 |
0.013 |
100 kernel weight |
G |
|
|
|
|
|
|
|
0.489** |
0.339* |
0.234 |
0.186 |
0.081 |
-0.118 |
P |
|
|
|
|
|
|
|
0.125 |
0.134 |
0.049 |
0.182 |
0.077 |
-0.108 |
|
E |
|
|
|
|
|
|
|
0.209 |
0.069 |
0.014 |
0.128 |
0.061 |
0.105 |
|
Cob length |
G |
|
|
|
|
|
|
|
|
-1.339 |
-1.672 |
-0.583** |
-0.590** |
-0.417** |
|
P |
|
|
|
|
|
|
|
|
0.287 |
-0.005 |
-0.097 |
-0.53 |
-0.075 |
|
E |
|
|
|
|
|
|
|
|
0.333* |
0.042 |
-0.113 |
0.036 |
-0.143 |
Cob diameter |
G |
|
|
|
|
|
|
|
|
|
-0.224 |
-0.039 |
0.180 |
-0.109 |
|
P |
|
|
|
|
|
|
|
|
|
-0.046 |
0.006 |
-0.034 |
-0.021 |
|
E |
|
|
|
|
|
|
|
|
|
-0.029 |
0.109 |
-0.173 |
0.113 |
Leaf temperature |
G |
|
|
|
|
|
|
|
|
|
|
0.638** |
-0.725** |
0.080 |
|
P |
|
|
|
|
|
|
|
|
|
|
0.099 |
-0.109 |
0.055 |
|
E |
|
|
|
|
|
|
|
|
|
|
-0.177 |
0.041 |
0.293 |
SPAD value |
G |
|
|
|
|
|
|
|
|
|
|
|
-0.147 |
-0.022 |
|
P |
|
|
|
|
|
|
|
|
|
|
|
-0.128 |
-0.018 |
|
E |
|
|
|
|
|
|
|
|
|
|
|
-0.008 |
0.172 |
Transpiration rate |
G |
|
|
|
|
|
|
|
|
|
|
|
|
0.016 |
P |
|
|
|
|
|
|
|
|
|
|
|
|
0.013 |
|
E |
|
|
|
|
|
|
|
|
|
|
|
|
-0.007 |
*
and ** denotes significance at 5 and 1 per cent level of significance
Table
2: Genotypic, phenotypic and environmental correlation coefficients among different
characters in winter maize under ESM conditions
Character
|
|
Days to 50% silking |
ASI |
Plant height |
Ear height |
Nodes bearing
adventitious roots |
Yield |
100 kernel weight |
Cob length |
Cob diameter |
Leaf temperature |
SPAD value |
Transpiration rate |
PAR |
Days
to 50% tasseling |
G |
0.427** |
-0.318* |
0.005 |
0.162 |
0.258 |
0.036 |
0.098 |
-0.119 |
-0.278 |
-0.626** |
0.109 |
-0.070 |
0.090 |
P |
0.330* |
-0.435** |
-0.022 |
0.031 |
0.111 |
0.021 |
0.057 |
-0.126 |
-0.282 |
-0.333* |
0.077 |
-0.049 |
0.057 |
|
|
E |
0.171 |
-0.619** |
-0.098 |
-0.226 |
-0.176 |
0.128 |
-0.104 |
-0.196 |
-0.287 |
-0.377* |
0.014 |
-0.016 |
-0.044 |
Days
to 50% silking |
G |
|
0.725** |
0.133 |
-0.095 |
-0.263 |
0.183 |
0.275 |
0.042 |
-0.089 |
0.235 |
0.099 |
0.250 |
0.112 |
P |
|
0.657** |
0.117 |
-0.101 |
-0.196 |
0.134 |
0.229 |
-0.011 |
-0.048 |
-0.091 |
0.071 |
0.182 |
0.116 |
|
|
E |
|
0.507** |
0.050 |
-0.118 |
0.015 |
-0.008 |
-0.028 |
-0.272 |
0.034 |
-0.256 |
-0.32 |
-0.006 |
0.173 |
ASI |
G |
|
|
0.150 |
-0.213 |
-0.409** |
0.175** |
0.225 |
0.143 |
0.190 |
0.601** |
-0.055 |
0.356** |
0.055 |
|
P |
|
|
0.152 |
-0.125 |
-0.250* |
0.116** |
0.183 |
0.107 |
0.195 |
0.142 |
-0.044 |
0.236 |
0.041 |
|
E |
|
|
0.180 |
0.089 |
0.151 |
-0.22 |
0.381 |
-0.013 |
0.205 |
0.096 |
-0.015 |
-0.030 |
-0.011 |
Plant
height |
G |
|
|
|
0.589** |
-0.035 |
0.269 |
0.569** |
0.388** |
0.504** |
-0249 |
-0.043 |
-0.095 |
0.046 |
|
P |
|
|
|
0.542** |
-0.010 |
0.272 |
0.509** |
0.361* |
0.340* |
-0.165 |
-0.058 |
-0.069 |
0.033 |
|
E |
|
|
|
0.357* |
0.105 |
0.302* |
-0.074 |
0.174 |
-0067 |
-0.329* |
-0.139 |
0.031 |
-0.082 |
Ear
height |
G |
|
|
|
|
0.102 |
0.134 |
0.284 |
0.231 |
0430** |
-0.616** |
-0.181 |
-0.193 |
0.116 |
|
P |
|
|
|
|
0.107 |
0.096 |
0.232 |
0.214 |
0.296* |
-0.116 |
-0.143 |
-0.098 |
0.072 |
|
E |
|
|
|
|
-0.081 |
-0.018 |
-0.115 |
0.140 |
0.026 |
-0.043 |
0.004 |
0.180 |
-0.211 |
Nodes
bearing adventitious roots |
G |
|
|
|
|
|
0.190 |
-0.009 |
-0.303* |
0.019 |
-0.966** |
0.159 |
-0.338* |
-0.079 |
P |
|
|
|
|
|
0.130 |
0.007 |
-0.226* |
0.028 |
-0.209 |
-0.153 |
-0.286 |
-0.081 |
|
E |
|
|
|
|
|
0.060 |
0.164 |
0.179 |
0.053 |
-0.124 |
-0.129 |
-0.133 |
-0.112 |
|
Yield
|
G |
|
|
|
|
|
|
0.322* |
0.236 |
0.186 |
-0.146 |
0.203 |
0.179 |
-0.046 |
|
P |
|
|
|
|
|
|
0.279* |
0.206 |
0.114 |
-0.149 |
0.117 |
0.158 |
-0.059 |
|
E |
|
|
|
|
|
|
0.081 |
0.083 |
-0.026 |
-0.254 |
-0.202 |
0.097 |
-0.165 |
100
kernel weight |
G |
|
|
|
|
|
|
|
0.186 |
0.367* |
0.193 |
-0.049 |
-0.103 |
0.085 |
P |
|
|
|
|
|
|
|
0.156 |
0.248 |
0.053 |
-0.046 |
-0.087 |
0.077 |
|
E |
|
|
|
|
|
|
|
-0.249 |
-0.211 |
0.098 |
-0.034 |
-0.015 |
-0.069 |
|
Cob
length |
G |
|
|
|
|
|
|
|
|
0.528** |
0.257 |
-0.028 |
0.004 |
0.023 |
|
P |
|
|
|
|
|
|
|
|
0.419** |
0.0009 |
-0.013 |
-0.008 |
0.020 |
|
E |
|
|
|
|
|
|
|
|
0.179 |
-0.105 |
0.084 |
-0.064 |
-0.008 |
Cob
diameter |
G |
|
|
|
|
|
|
|
|
|
-0.618** |
-0.324* |
0.238 |
-0.025 |
|
P |
|
|
|
|
|
|
|
|
|
0.087 |
-0.229 |
0.145 |
-0.023 |
|
E |
|
|
|
|
|
|
|
|
|
0.270 |
-0.011 |
-0.031 |
-0.026 |
Leaf
temperature |
G |
|
|
|
|
|
|
|
|
|
|
-0.312* |
0.488** |
-1.466 |
|
P |
|
|
|
|
|
|
|
|
|
|
-0.030 |
0.062 |
-0.250 |
|
E |
|
|
|
|
|
|
|
|
|
|
-0.049 |
-0.023 |
0.006 |
SPAD
value |
G |
|
|
|
|
|
|
|
|
|
|
|
0.030 |
-0.102 |
|
P |
|
|
|
|
|
|
|
|
|
|
|
0.024 |
-0.095 |
|
E |
|
|
|
|
|
|
|
|
|
|
|
0.001 |
-0.049 |
Transpiration
rate |
G |
|
|
|
|
|
|
|
|
|
|
|
|
-0.107 |
P |
|
|
|
|
|
|
|
|
|
|
|
|
-0.083 |
|
E |
|
|
|
|
|
|
|
|
|
|
|
|
0.043 |
*
and ** denotes significance at 5 and 1 per cent level of significance