The Journal of Research ANGRAU
Contents of 41(1) 2013 - acharya ng ranga agricultural university
Contents of 41(1) 2013 - acharya ng ranga agricultural university
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<strong>Research</strong> Notes<br />
J.Res. <strong>ANGRAU</strong> 41(1) 105-108, 2013<br />
CORRELATION AND PATH COEFFICIENT ANALYSIS FOR YIELD AND<br />
PHYSIOLOGICAL ATTRIBUTES IN RICE (Oryza sativa L.) HYBRIDS UNDER<br />
SALINE SOIL CONDITIONS<br />
M.SUDHARANI, P.RAGHAVA REDDY, G.HARIPRASAD REDDY and CH.SURENDRA RAJU<br />
Seed <strong>Research</strong> and Technology Centre, Rajendranagar, Hyderabad-500030<br />
Date <strong>of</strong> Receipt : 21.09.2012 Date <strong>of</strong> Acceptance : 09.11.2012<br />
Correlation studies and path coefficient<br />
analysis were undertaken to know the inter<br />
relationship <strong>of</strong> yield components and physiological<br />
parameters related to salt tolerance and their<br />
usefulness in selection programmes under salt stress.<br />
In the present investigation 28 rice hybrids<br />
derived by crossing eight genotypes (RPBio-226,<br />
Swarna , CSR-27, CSR-30, CST-7-1, CSRC(S)7-1-<br />
4, SR26-B and CSRC(S)5-2-2-5 in half diallel manner<br />
were utilized based on their reaction to salinity<br />
tolerance and were evaluated during kharif, 2010<br />
under salt affected soils <strong>of</strong> Agricultural <strong>Research</strong><br />
Station, Machilipatnam. Seedlings <strong>of</strong> 30 days old were<br />
transplanted in the main field having electrical<br />
conductivity <strong>of</strong> 7.9 dS/m and pH <strong>of</strong> 7.7 following<br />
randomized block design with three replications. <strong>The</strong><br />
recommended agronomic, cultural and plant<br />
protection measures were followed in conducting the<br />
experiment. Genotypic and phenotypic correlation<br />
coefficients were calculated among eight parents<br />
using the formulae suggested by Al-Jibouri et al.<br />
(1958) and their significance was tested by using the<br />
‘r’ table values (Fisher and Yates, 1963) at n-2<br />
degrees <strong>of</strong> freedom, where ‘n’ denotes the number <strong>of</strong><br />
treatments used in the calculation.<br />
To estimate the direct and indirect effects<br />
<strong>of</strong> the yield components on the yield, the statistical<br />
tool employed was path coefficient analysis as<br />
suggested by Wright (1921) and illustrated by Dewey<br />
and Lu (1959). <strong>The</strong> path coefficients were obtained<br />
by solving the ‘p’ normal equations following the<br />
matrix method given by Singh and Chowdhary (1985).<br />
In the present investigation, the genotypic and<br />
phenotypic correlations amongst the traits followed<br />
almost similar trend <strong>of</strong> association, the former being<br />
a little higher in most <strong>of</strong> the cases, indicating the<br />
existence <strong>of</strong> a strong inherent association between<br />
the characters. Further, dissecting these associations<br />
as direct and indirect effects through path analysis<br />
showed direct contribution <strong>of</strong> each component trait<br />
on yield and indirect effect it has through association<br />
on other component traits.<br />
<strong>The</strong> yield component viz., plant height<br />
(0.5847), number <strong>of</strong> tillers plant -1 (0.7789), number <strong>of</strong><br />
productive tillers plant -1 (0.5753), panicle length<br />
(0.8353), panicle weight (0.5500), number <strong>of</strong> filled<br />
grains panicle -1 (0.7809), spikelet fertility per cent<br />
(0.7190), 1000-grain weight (0.5399), root/shoot ratio<br />
(0.4694) and harvest index (0.8128) were significantly<br />
and positively correlated with grain yield (Table 1) in<br />
rice hybrids tested under saline conditions. On the<br />
other hand Na + /K + ratio and SPAD chlorophyll meter<br />
readings exhibited significant negative association<br />
with grain yield, while the effect <strong>of</strong> days to 50 per<br />
cent flowering was non-significant. <strong>The</strong> findings <strong>of</strong><br />
earlier researchers viz., Bala (2001) for plant height;<br />
Zeng and Shannon (2000), Natarajan et al. (2005) for<br />
number <strong>of</strong> tillers plant -1 ; Ravindra Babu (1996),<br />
Natarajan et al. (2005) for number <strong>of</strong> productive tillers<br />
plant -1 ; Bala (2001) for panicle length; Buu and Tuan<br />
(1991), Ravindra Babu (1996), Natarajan et al. (2005)<br />
for number <strong>of</strong> filled grains panicle -1 ; Natarajan et al.<br />
(2005) for 1000-grain weight ; Sajjad (1990) and Balan<br />
et al. (1999) for harvest index were in line with the<br />
present readings. However, Asch et al. (2000)<br />
reported strong negative association <strong>of</strong> Na + /K + ratio<br />
with grain yield which is in agreement with the present<br />
findings. Under saline soil conditions plant height,<br />
number <strong>of</strong> tillers plant -1 , productive tillers plant -1 ,<br />
panicle length, panicle weight, number <strong>of</strong> filled grains<br />
panicle -1 , spikelet fertility per cent, SPAD values and<br />
test weight showed strong positive association with<br />
grain yield plant -1 under stressed environment.<br />
email: madugula.sudharani@yahoo.com<br />
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