MSc

The research programme entitled “Efficiency of foliar and soil applied nutrients in irrigated rice” was conducted in the farmer’s field, Thathamangalam, Palakkad during Mundakan season October 2014 – February 2015 to compare the relative efficiency of soil and foliar applied nutrients especially magnesium, zinc and boron alone or in combination in rice. The treatments included soil test based all nutrient package inclusive of FYM, soil test based all nutrients but N at 90 kg/ha inclusive of FYM, soil test based all nutrients but N based on C:N ratio, package of practices recommendation for rice manuring (POP NPK + FYM), NPK alone, soil application of MgSO4 @ 80 kg ha-1, ZnSO4 @ 20 kg ha-1, Borax @ 10 kg ha-1, foliar spray of MgSO4 @ 1%, ZnSO4 @ 0.5%, Borax @ 0.25%, combined soil application of MgSO4 @ 80 kg ha-1 + ZnSO4 @ 20 kg ha-1 + Borax @ 10 kg ha-1, combined foliar application of MgSO4 @ 1% + ZnSO4 @ 0.5% + Borax @ 0.25% and an absolute control. Soil application of Mg, Zn and B were done as basal, and foliar applications were given at 20 and 40 DAT of rice as per the treatments.
The growth characters of rice such as plant height, number of tillers, LAI and dry matter production were significantly increased by the application of MgSO4, ZnSO4 and Borax along with POP NPK irrespective of method of application whether as individual application or combined application. The application of POP NPK inclusive of FYM and the entire soil test based nutrient applications were also resulted in noticeable improvement in growth characters. Combined foliar application of Mg, Zn and B resulted in higher number of productive tillers and combined soil application of Mg, Zn and B produced higher LAI.
The combined foliar application of Mg, Zn and B significantly increased the number of spikelet/panicle along with soil test based all nutrients except N and Nat 90 kg/ha inclusive of FYM. Irrespective of the method of application, Zn application enhanced the fertility percentage of grain compared to other treatments. Soil application of Mg and Zn produced significantly higher 1000 grain weight and it was statistically similar to all the nutrient applied plots irrespective of the method of application. The highest grain yield of 6.28 t ha-1 was observed with combined soil application of Mg, Zn and B along with POP NPK and it was similar to that of combined foliar application of Mg, Zn and B along with POP NPK. The application of B (either soil or foliar) also resulted in higher grain yield. The highest straw yield was observed in B applied treatments irrespective of method of application. The B:C ratio was higher for soil application of B and it was similar to its foliar application. Combined application (soil or foliar) of Mg, Zn and B produced higher B:C ratio than that of package of practices recommendation for rice.
The nutrient content of rice plants were also influenced by the application of MgSO4, ZnSO4 and Borax along with POP NPK. The combined application of Mg, Zn and B increased the content and uptake of Mg. The higher Zn content was observed in foliar application of ZnSO4 along with POP NPK. The highest Zn uptake was observed in combined soil application of Mg, Zn and B. The combined foliar application of Mg, Zn and B increased the B content in rice. Foliar application of B resulted in higher B uptake.
There was no significant difference between the individual application and combined application of MgSO4, ZnSO4 and borax on the soil characteristics pH, EC, OC and available nutrient status of soil after the experiment. Available status of all the nutrients except S, Fe, Zn and Cu decreased after the experiment.