MSc

The experiment entitled “Integrated nutrient approach on productivity
enhancement of rice in oxyaquic fluent soils of Northern Kerala” was conducted
to study the effect of organic manures along with micronutrient mixtures on
growth, yield, pest and disease incidence, nutrient uptake and economics of
wetland rice in farmer’s field during virippu season 2017. The experiment was
laid out in randomized block design with 12 treatments and 3 replications. The
treatments were T1 - Farmer’s practice (FYM 5 t ha -1 + 18:18:18), T2 - Fertilizer
recommendation on the STCR basis (75.6: 57.6: 37.35 kg ha -1 NPK), T3 - POP
Recommendation of KAU (90:45:45 kg ha-1 NPK ), T4 - FYM (5t ha-1) + Neem
cake (400 kg ha-1) + Groundnut cake (400 kg ha -1), T5 - T3 + Ayar (500 kg ha-1 as
basal dose), T6 - T3 + Sampoorna (5g l-1 at 1-2 days before transplanting and 10
g l-1 at 50 DAT as foliar spray respectively), T7 - T4 + Ayar (500 kg ha-1 as basal
dose), T8 - T4 + Sampoorna (5g l-1 at 1-2 days before transplanting and 10 g l-1
and at 50 DAT as foliar spray respectively), T9 - T5 + Si (100 kg ha-1 as calcium
silicate), T10 - T6 + Si (100 kg ha-1 as calcium silicate), T11 - T7 + Si (100 kg ha-1
as calcium silicate) and T12 - T8 + Si (100 kg ha-1
as calcium silicate). The
available N, P and K status of the experimental field ranged from low to medium
and the secondary and micronutrients were in the sufficiency level. All the
treatments were applied as per the technical programme.
The results of the experiment showed that the growth and yield attributes
such as plant height and number of tillers hill-1, number of panicles hill-1, filled
grains panicle-1, test weight and lowest number of chaffy grains were significantly
influenced by application of POP recommendation of KAU along with
micronutrient mixtures viz. Sampoorna and Ayar. The treatment T9 (T5 + Si)
recorded maximum grain yield which was on par with T6 (T3 + Sampoorna).
Straw yield was maximum in T5 (T3 + Ayar) and was on par with T6. Higher
harvest index was recorded in treatment T9 (T5 + Si).
At harvest, the available N and P status of the soil were increased whereas
the available K was decreased when compared to the initial soil nutrient status.
Application of FYM + Neem cake + Groundnut cake along with Sampoorna

recorded higher soil available N and application of fertilizers based on POP
recommendation of KAU along with Ayar recorded maximum soil available P
content. Plant nutrient content viz. N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and Si of both
shoot and root were analyzed at maximum tillering, PI stage and at harvest. In the
shoot, all the nutrients showed a declining trend from maximum tillering to PI
except sulphur. The content of Fe showed sharp decrease from maximum tillering
to harvest stage. The total uptake of nutrients showed a significant difference
among treatments. Phosphorus uptake was maximum in treatment T10 and T6
recorded maximum K uptake. The treatment T9 recorded maximum uptake of
nutrients such as Ca, Zn and Mn. T 5 recorded maximum Mg uptake. Application
of FYM + Neem cake + Groundnut cake along with Sampoorna and silicon
reduced the uptake of Fe. Correlation study revealed that plant nutrient content
such as P, Ca, Mg, Cu and Si showed a positive relationship with yield at different
critical growth stages.
The treatment with POP Recommendation of KAU along with Sampoorna
(T6) recorded maximum yield, gross return, net return and B:C ratio whereas,
application of POP Recommendation of KAU along with Ayar and Si were also
equally good with yield and ease of application.
In general, the integrated use of organic and inorganic sources of nutrients
along with secondary, micronutrients and Si not only increase the growth
parameters and yield attributes but also increase the soil nutrient level and
economics of wetland rice cultivation.