physicochemical

J.Res. ANGRAU 39(1&2)14-19, 2011
RESPONSE OF LOW LAND RICE TO SOURCE, TIME
AND METHOD OF ZINC APPLICATION
M. MALLA REDDY, B. PADMAJA, R. UMA REDDY and D. VISHNU VARDHAN REDDY
Regional Agricultural Research Station,
Acharya N.G.Ranga Agricultural University, Warangal – 506 007
ABSTRACT
Field experiments were conducted during kharif, 2008 and 2009 in clay loam soils to study the influence of
zinc on growth and yield of low land rice at Regional Agricultural Research Station, Warangal, Andhra Pradesh.
Results revealed that there was no significant difference between two sources of Zn i.e., ZnS04 and Biozinc but
significant difference was observed in method of application i.e., basal and foliar application in producing yield. It
was found that significantly higher yield attributes, grain yield (7312 and 7042 kg/ha, respectively) and net returns
(Rs.51, 212 and 62,344/ha, respectively) were recorded with basal application of Biozinc or ZnS04 @ 50 kg/ha +
foliar spray @ 3 g/l at 30 DAT. Even foliar spray of ZnS04 or Biozinc @ 3 g/l at 30 and 45 DAT recorded significantly
higher yield attributes, grain yield and net returns over control but inferior to basal application of Zn during both the
years of study.
In Andhra Pradesh, cultivation of zinc
sensitive varieties (MTU 1001, MTU 1010 etc.,) in
large areas coupled with continuous cropping without
rotation, indiscriminative application of complex
fertilizers in rice induced Zn deficiency. Thus, next
to N and P deficiency, zinc is becoming the most
important nutritional factor, limiting the grain yield of
wetland rice. The deficiency can be corrected by soil
applications or foliar sprays of a suitable Zn fertilizer.
In general, recommendations for soil application of
Zn for crops vary from 5 to 17 kg Zn ha -1 in the form
of ZnSO 4
(Fenster et al. 1984). Dose and time of zinc
application are important for correcting the deficiency.
Source of zinc is also a critical factor for increasing
its availabile form of zinc to rice for higher yields.
The information related to the source and time of Zn
application is inadequate in coarse rice varieties in
Andhra Pradesh. Keeping in view of these factors,
the present investigation was taken up to know the
influence of Zinc on growth and yield of low land rice.
MATERIALS AND METHODS
Field experiments were conducted during
kharif, 2008 and 2009 at Regional Agricultural
Research Station, Warangal, Andhra Pradesh. The
soil was clay loam with a P H of 8.5 and EC of 0.6 d
Sm -1 , low in organic carbon (0.5 %) and available
nitrogen (220 kg/ha), high in available P (59 kg P 2
O 5
/
ha) and available K (384 kg K 2
O/ha) and available Zn
at 0.7 ppm. The experiments were laid out in a
Randomized Block Design comprising of seven
treatments i.e., T 1
:Control, T 2
: 50 kg ZnS0 4
/ha as
basal application,T 3
: 50 kg ZnS0 4
/ha as basal
application + foliar spray @ 3g/l at 30 DAT, T 4
: 50
kg Biozinc/ha as basal application, T 5
: 50 kg Biozinc/
ha as basal application + foliar spray @ 3 g/l at 30
DAT, T 6
: Foliar spray of ZnS0 4
@ 3 g/l at 30 and 45
DAT and T7: Foliar spray of Biozinc @ 3 g/l at 30
and 45 DAT. Biozinc is a natural derivative of glucose
fermentation and contains 12% zinc gluconate
(organic zinc) on dry weight basis along with sulphur
( as certified by the manufacturing company). Rice
variety, MTU-1001(Vijetha) was used in the study.
Rice nursery was sown on 1 st July and 28 th June
and transplanting was taken up on 1 st August and
29 th July during 2008 and 2009, respectively. The
crop was harvested on 16 th and 13 th November during
2008 and 2009, respectively. A rainfall of 421.5 mm
was received during 2008 in 23 rainy days and 309.4
mm during 2009 in 20 rainy days throughout the crop
growth period. All the recommended practices were
followed. Observations on yield attributes and yield
of rice were recorded. Soil samples were drawn after
harvest of rice during two years and analyzed for
DTPA-extractable Zn as per the procedure given by
Lindsay and Norvell (1978).
E-mail: maduri_agron@yahoo.com
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