EVALUATION OF BIOFERTILIZERS IN IRRIGATED RICE: EFFECTS ON GRAIN YIELD AT DIFFERENT FERTILIZER RATE - Organic Agricultural Practices - page 145

However, there was a trend of higher yield increases due to biofertilizer
use at low to medium inorganic fertilizer rates (Table 4, Figure 1). This
trend was most obvious for the BN biofertilizer whereas the performance
of the BS and BG biofertilizers was less consistent.

TABLE 4: Grain yield of the variety PSB Rc18 as affected by inorganic fertilizer level and
biofertilizer treatments in all four experimental seasons and both sites.

Season Biofertil-

izer treat-
ment ***

Inorganic fertilizer treatment **

0% RR 25% RR 50% RR 100% RR Mean *

Grain yield (kg·ha −1 )

2008/09 DS BG 4016 4421 4569 5134 4508 a

BN 4163 4753 4900 5081 4683 a

BS 4351 4569 4375 5173 4610 a

Control 4062 4440 4630 4799 4534 a

Mean * 4158 c 4548 b 4617 b 5034 a

2009 WS BG 1963 1975 2502 2383 2206 bc

BN 2149 2417 2420 2604 2398 a

BS 2005 2179 2287 2674 2286 ab

Control 1902 2000 2038 2165 2026 c

Mean * 2005 c 2143 bc 2038 ab 2456 a

2010 WS BG 4326 4303 4670 4596 4482 ab

BN 4197 4529 5131 4794 4663 a

BS 3952 4336 4578 4732 4399 bc

Control 3389 4245 4274 4716 4219 c

Mean * 3965 c 4353 b 4659 a 4710 a

2010/11 DS BG 4145 4665 4926 5556 4825 a

BN 4009 5049 5262 5519 4960 a

BS 3955 4876 5175 5492 4861 a

Control 3801 4420 4707 5265 4548 b

Mean * 3977 c 4751 b 5014 b 5458 a

* In each season, mean values in a column or row followed by the same letter are
not significantly different at the 5% level of significance according to LSD; ** RR:
Recommended rate: 120-60-60 kg N-P 2 O 5 -K 2 O ha −1 in the DS; 90-30-30 kg N-P 2 O 5 -K 2 O
ha− 1 in the WS; *** Biofertilizer treatments are described in detail in the text.