CONTENTS

YIELD, NUTRIENT UPTAKE AND ECONOMICS OF CASTOR
yield of the castor. The seed yields were analysed
statistically and presented in Table 1 and illustrated
in Figure 1.
Among the integrated nutrient management
treatments, maximum seed yield was recorded in T 6
(75% RDN-Inorganic + 12.5% RDN-FYM +12.5%
RDN-Neem cake) (346.30kg ha -1 ) which was on par
with T 2
(100% RDN-Inorganic) (319.60 kg ha -1 ) and
T5 (75% RDN-Inorganic + 25% RDN-Neem cake)
(324.17 kg ha -1 ) and significantly higher over the other
treatments. Significantly lower seed yield was
recorded in T 1
(control) (120.10 kg ha -1 ) than the other
treatments. The reduction may be due to the severe
competition with Pongamia for nutrients and moisture.
The results were in agreement with Mutanal et al.
(2009). Data on correlation coefficients also indicated
that all growth characters and yield attributes were
positively and significantly correlated with seed yield
as it was evident from Table 4.15.
The higher seed yield in T 6
(75% RDN-Inorganic
+ 12.5% RDN-FYM +12.5% RDN-Neem cake)
(346.30kg ha -1 ) could be attributed to conjunctive use
of organic and inorganic sources of nitrogen which
increased the availability of nitrogen for favourable
plant growth and further nitrogen fertilization
increases the cation exchange capacity of plant roots
and thus became efficient in absorption of nutrient
ions (Mathukia and Modhwadia, 1995).
Comparatively low yields of castor were due to
heavy infestation of Botrytis grey mold disease and
more number of rainy days in the crop growth period
(55 rainy days) which coincided with capsule formation
stage. These results were also in conformity with
the findings of Baby and Reddy (1998), Patel et al.
(2005) and Kumar and Kanjana (2009).
Stalk Yield
The stalk yield recorded under different
integrated nutrient management treatments was
analysed statistically and presented in Table 1 and
illustrated in Figure 1.
Integrated nutrient management treatments
have brought about significant differences in the stalk
yield of the castor. Among the integrated nutrient
management treatments, maximum stalk yield was
recorded in T 6
(75% RDN-Inorganic) + 12.5% RDN-
FYM +12.5% RDN-Neem cake) (1423.93 kg/ha) and
it was on par with T 2
(100% RDN-Inorganic) (1361.73
kg ha -1 ) and T 5
(75% RDN-Inorganic + 25% RDN-
Neem cake) (1347.31 kg ha -1 ) and significantly higher
119
over the other treatments. Significantly lower stalk
yield was noticed in T 1
(control) (568.66 kg ha -1 ) than
all the other treatments.
Higher stalk yield in T 6
(75% RDN-Inorganic +
12.5% RDN-FYM +12.5% RDN-Neem cake) (1423.93
kg ha -1 ) was mainly attributed to the increased
availability of major and micronutrients due to
cumulative effect of organic manures like FYM and
neem cake and also due to higher plant height, leaf
area, number of branches and dry matter production
in the treatment. The results were in agreement with
Kumar and Kanjana (2009), Reddy et al. (1993) and
Raghavaiah and Babu (2000).
Harvest Index
The harvest index recorded under different
integrated nutrient management treatments was
analysed statistically and presented in Table 1.
Maximum harvest index was recorded in T 6
(75% RDN-Inorganic + 12.5% RDN-FYM +12.5%
RDN-Neem cake) (24.32%) and statistically it was
on par with all the treatments except with T 1
(control)
(21.12%). Maximum harvest index of castor in T 6
was mainly attributed to partitioning of dry matter
towards seed due to high availability of nutrients by
application of organic manures like FYM and neem
cake. The results were in agreement with Kumar and
Kanjana (2009), Reddy et al. (1993) and Raghavaiah
and Babu (2000).
Oil Content and Oil Yield
The oil content recorded under different
integrated nutrient management treatments was
analysed statistically and presented in Table 1.
Integrated nutrient management practices did
not influence the oil content of castor. Maximum oil
content was recorded in T 7
(50% RDN-Inorganic +
25% RDN-FYM) (52.43%) and it was followed by T 1
(control) (52.37%) and T 8
(50% RDN-Inorganic +
25%RDN-Neem cake) (51.98%). Minimum oil content
was noticed in T 2
(100% RDN-Inorganic) (50.63%).
However, the oil yield was significantly influence by
the INM treatments. T 6
(75% RDN-Inorganic + 12.5%
RDN-FYM +12.5% RDN-Neem cake) (181.57 kg ha -
1
) recorded significantly higher oil yield over all the
other treatments. The increase in the oil yield in T 6
was attributed to higher seed yield obtained in this
treatment.
The oil content in oilseeds is often a genetically
controlled parameter and may not be altered much