M Sc

An experiment entitled “Performance evaluation of Rakthasali rice under different
seed rates and nutrient management” was carried out at the Integrated Farming System
Research Station, Karamana from October 2020 to January 2021 with the objectives to
standardize the seed rate and to evaluate different nutrient management techniques for better
yield and quality in Rakthasali rice.
The experiment was laid out in factorial RBD with 12 treatment combinations
replicated thrice. There were two factors ie., seed rate (S) and nutrient management (N) in
three and four levels respectively. The three levels of seed rate were 60 kg ha-1 (s1), 80 kg ha-1
(s2) and 100 kg ha-1 (s3). The four levels of nutrient management were KAU POP
recommendation for short duration rice ie., 5 t ha-1
FYM + 70:35:35 kg ha-1 N, P and K (n1),
KAU Adhoc organic recommendation for short duration rice ie., 5 t ha-1
FYM + 750 kg ha-1
neem cake half as basal and half as top dressing at active tillering (AT) stage (n2), basal dose
of organics (5 t ha-1
FYM) and PGPR Mix I (@ 2.5 kg mixed with 500 kg dried and
powdered FYM for one ha applied at AT and panicle initiation (PI) stages (n3) and basal dose
of organics (5 t ha-1
FYM + 375 kg ha-1
neem cake at AT) + foliar spray of panchagavya
(3%) at flowering and PI stages (n4).
The results of the study indicated that seed rate and nutrient management could
significantly influence growth parameters, physiological characters, nutrient uptake, yield
attributes, yield and economics of cultivation.
Seed rate of 80 kg ha-1 (s2) registered significantly taller plants at maximum tillering
(MT) (67.81 cm), panicle initiation (72.52 cm) and harvest stages (89.99cm). Tiller number
m
-2 was also influenced by seed rate with s2 resulting in significantly higher tiller number of
240.25, 231.83 and 214.67 at MT, PI and harvest stages respectively. Shoot weight was also
found influenced by seed rates with s2 resulting in significantly the highest shoot weight of
24.56 g plant-1
. The combined effect of taller plants with more tillers and higher shoot weight
resulted in significantly highest drymatter production (4797 kg ha-1
) under s2.
Nutrient management with KAU POP recommendation (n1) could result in
significantly taller plants at MT (66.99 cm), PI (73.15 cm) and harvest stages (90.44 cm) of
crop. Tiller number m-2 were also found significantly influenced with n1 resulting in 233.67,
226.66 and 207.33 tillers respectively at MT, PI and harvest stages of crop. Significantly
highest shoot weight of 25.22 g plant -1 was recorded with n1. The combined effect of taller
plants with more number of tillers and shoot weight resulted in significantly the highest dry
matter productionof 4790.22 kg ha-1
under n1. KAU Adhoc organic package (n2) also
recorded a performance on par to n1.
Physiological parameters like LAI, SCMR and nutrient uptake were also significantly
influenced by seed rate and nutrient management. Seed of 80 kg ha-1
(s2) resulted in
significantly the highest LAI of 2.77 and SCMR of 29.10 and 35.07 respectively at PI and
flowering stages. Significantly the highest nutrient uptake ie., 49.30 kg ha-1
of N, 14.18 kg ha1 of P and 46.25 kg ha-1
of K were obtained with s2.
KAU POP recommendation of nutrients (n1) resulted in significantly the highest LAI
of 2.75 and SCMR of 29.52 and 35.01 respectively at PI and flowering stages of crop.
Significantly highest nutrient uptake ie., 49.22 kg ha-1
of N, 14.11 kg ha-1 of P and 46.58 kg
ha-1 K were also obtained with n1. KAU Adhoc organic package (n2) also recorded
comparable performance as that with n1
Yield attributes viz., number of panicles m-2
, length of panicle, total grains per
panicle, number of filled grains per panicle and thousand grain weight were significantly
influenced by seed rate and nutrient management. Seed rate of 80 kg ha-1
(s2) resulted in
significantly the highest number of panicles per unit area (174.92 m-2
), the longest panicles
(18.07 cm), the highest number of grains per panicle (84.75), higher number of filled grains
per panicle (67.25) and thousand grain weight (11.349 g).
KAU recommended nutrient management (n1) resulted in significantly the highest
number of panicles (169.22 m-2
), longest panicles (18.32 cm), highest number of grains per
panicle (84.78), highest number of filled grains per panicle (69.89) and thousand grain weight
(11.380 g). Performance of KAU Adhoc organic package (n2) was on par with n1
Grain yield, straw yield and harvest index (HI) were also significantly influenced by
seed rate and nutrient management with s2 recording the significantly the highest grain
(1.59 t ha-1
) and straw (3.41 t ha-1
) yields and HI of 0.323.
Significantly highest grain (1.61 t ha-1
) and straw (3.43 t ha-1
) yields and HI (0.322)
were recorded with n1 (integrated nutrient management as per KAU POP). With regard to the
organic nutrition practices experimented for the crop, KAU Adhoc organic package (n2) was
on par with n1.
Nutrient management with KAU Adhoc organic package (n2) resulted in significantly
highest grain protein content of 11.33 g 100g-1
.
Post harvest soil analysis revealed that N, P and K availability were significantly
influenced with KAU POP recommendation for short duration rice (n1) recording
significantly highest soil N (330 kg ha-1
), P (53 kg ha-1
) and K (52 kg ha-1
). KAU
recommended Adhoc organic package (n2) was on par with n1.
Net returns and B:C ratio also varied significantly with seed rate and nutrient
management with s2 recording significantly highest net income of ₹55507/- and B:C ratio of
1.46. Among different nutrient management practices KAU POP recommendation (n1)
resulted in significantly highest net returns of ₹62175/- and B:C ratio of 1.53.
The interaction effect of seed rate and nutrient management could also make a
significant influence on growth parameters, physiological characters, nutrient uptake, yield
attributes, yield and economics of cultivation.
Seed rate @ 80 kg ha-1
+ KAU recommended integrated nutrient management (s2n1)
resulted in significant growth improvement which was reflected in plant height at maximum
tillering (71.93 cm), panicle initiation (76.57 cm) and harvest (93.73 cm) stages. The same
treatment also recorded highest tiller count of 245 nos, 236 nos and 219 nos at MT, PI and
harvest stages respectively and the highest shoot weight of 26.89 g per plant.
The treatment combination s2n1 also resulted in significant improvement in
physiological characters like LAI (3.02) and SCMR of 32.13 and 38.03 at panicle initiation
and flowering stages respectively.
Treatment combination s2n1 also resulted in significant improvement in yield
attributes with higher number of panicles (180.67 m-2
), longest panicle (19.16 cm), highest
number of grains per panicle (87), higher number of filled grains per panicle (72.67), grain
yield (1.69 t ha-1
), straw yield (3.50 t ha-1
) and H.I of 0.327.
The treatment combination s2n1 also resulted in significantly the highest net returns of
₹70501/- and B:C ratio of 1.60.
The results of the study revealed that growth, physiological characters, nutrient
uptake, yield and economics of Rakthasali rice cultivation were significantly influenced by
varying seed rates and nutrient management. Seed rate of 80 kg ha-1
and crop nourishment
through the integrated nutrient management as recommended by KAU could be adjudged as
the best treatment.
Considering the productivity and economics, broadcasting at a seed rate of 80 kg ha-1
along with integrated nutrient management as per KAU POP for short duration rice ie., 5 tha-1
FYM + 70:35:35 kg N P K per ha could be recommended for Rakthasali, the medicinal rice
of Kerala.