Alachlor at both levels failed in effective control of Echinochloa crusgalli, E. colonum, Phyllanthus niruri, Commelina benghafensis, Digera arvensis, Ageratum.
Agric. Sci. Digest, 22 (1) : 36 - 38, 2002
EFFECT OF WEED MANAGEMENT ON GROWTH AND PRODUCTIVITY OF MAIZE-BLACKGRAM INTERCROPPING SYSTEM V.S. Shekhawat, M.S. Shaktawat and S.P.S. Tanwar Department of Agronomy, Rajasthan College of Agriculture Maharana Pratap University of Agriculture and Technology, Udaipur-313 001, India
ABSTRACT Weed free treatment resulted in maximum plant height, yield attributes and grain and straw yields of maize and blackgram. Amongst the herbicides, maximum values of above observation were recorded when metolachlor @ 1.0 kg ha'\ was applied. Planting in 2:2 rows of maizeblackgram intercropping proved superior in all observations recorded, over 1: 1 row planting system.
Maize and blackgram are the major crops of south Rajasthan and mostly grown in intercropping system. The environmental conditions in Kharil season are such to support luxuriant growth of weeds resulting in severe crop losses. The present study was undertaken with the objective to find Qut the effect of weed control on productivity of maize-blackgram intercropping system. An experiment was conducted at Rajasthan College of Agriculture, Udaipur during Kharif, 1996. The experiment was laid out in randomized block design with eight weed control treatments (weedy check, weed free throughout, alachlor @ 1.0 kg ha' l , alachlor @1.25 kg ha· l , metolachlor @ 1.0 kg ha- l and metolachlor 1.25 kg ha· l) and two planting patterns (1: 1 and 2:2 rows planting system). Each treatment was replicated four times. Preemergence spray of herbicides was applied as per treatments. Maize (variety Ganga-2) sown at a row to row distance of 60 cm and in betWeen them, one row of blackgram (variety T9) was sown in 1: 1 planting system. In 2:2 planting system, two rows of maize were planted at a distance of 30 cm followed by two rows of blackgram at the same distance. All the agronomic practices for raising the crop as rainfed were applied as per zonal recommend~tions,
Effect on Maize: Wood control treat-
ments significantly improved growth characters and yield attributes which resulted in higher yield of maize over control. The maize yield was maximum under weed free situation (Table 1). Metolachlor @ 1.0 kg hal and 1.25 kg hal and pendimenthalin @ 0.75 kg ha- l and 1 kg ha'l were found equally effective in increasing plant height, LAI at 60 DAS, seeds per cob, 1000 grain weight and grain and stover yields of maize. Weed free treatment and metolachlor@ 1.0 kg ha· 1 caused increase both in grain yield of maize (129.45%) and stover yields (124.04%) over weedy check, respectively. The increase in maize yield might be due to reduced weed competition as well as cumulative increase in growth characters due to favourable conditions created under weed free conditions. Alachlor at both levels failed in effective control of Echinochloa crusgalli, E. colonum, Phyllanthus niruri, Commelina benghafensis, Digera arvensis, Ageratum conzoides and Ec1ipta alba and proved statistically inferior to all other herbicides. The results are in close confirmity with the findings of Thakur and Singh (1990) and Thakur (1994). Of two intercropping patterns, highest LAI at 60 DAS, cobs per plant, seed per cob, 1000 grain weight and grain and stover yields were obtained under 2: 2 row planting system (Table 1). Effect on BIackgram : Weed control
@
3.70
3.32 3.69 0.35
192.8 194.0
NS
2:2
CD (P=0.05)
0.72
B. Planting pattern 1:1
18.28
201.0
1.25 kg hal
@
CD (p=0.05)
Metolachlor
3.75 3.85
201.0 203.0
1.0 kg ha· l
3.70
201.0
@
3.00
3.00
182.0
181.5
Metolachlor
Alachlor @ 1.25 kg ha' l Pendimenthalin @ 0.75 kg hal Pendimenthalin @ 1.0 kg ha' l
Alachlor
3.85
203.0
Weed free
1.0 kg ha' l
2.59
I.J\I at 60 DAS
177.0
Plant height at harvest (em)
A. Weed control Weedy
Treatment
11.74
308.8
294.0
23.94
307.5
311.5
308.5
307.5
295.5
295.5
1000 grain weight (g)
735
177.4
157.1
14.69
170.5
184.0
180.0
170.5
155.5
155.5
185.0
137.0
Maize
356.0
239.0
Seeds per eob
116.0
2.19
50.77
40.44
438
54.37
4.72
1088
97.1
9.44
111.1
116.2
54.53 55.07
111.0
54.23
87.5 87.0
32.17
33.49
46.0 117.0
24.58
vield (q ha ')
Stover
56.40
Grain yIeld (q ha")
0.92
25.90 0.98
20.21 24.3
1.83
20.65
26.50
25.50
23.25 21.25
23.65
26.80
16.75
Pods per plant
2:n
1.96
23.5
25.7
24.7
23.7 22.8
23.1
26.1
20.2
(em)
halVcst
Plant height at
0.24
5.5
5.0
0.48
4.8
5.8
5.6
4.9
5.4
4.8
5.9
4.6
Seeds per pod
3.65
Grain yield (q ha 1)
7.70
7.25
7.60
5.25
6.56 8.51 1.83 0.41
38.5
36.6
3.78 0.82
38-7 10.35 37.5 7.45
38.3
37.5
37.4
37.1
38.7 11.05
35.4
1000 grain weight (g)
Blackgram
66.09
44.60
42.09
73.97
72.01
51.18
7.82
0.82
3.91
19.86 64.57
18.8
1.65
18.85 66.60
25.4
18.95 67.12
18.8
19.3
18.1
26.1
9.15 30.55
Maize Straw equivalent yield yield Iq ha'l (q ha 1)
Table 1. Effect of weed management and planting system on growth, yield attributes and yield of maize-blackgram intercropping system
-..J
W
N 0 0 N
:-'
p
z
~ N _N
38 '
AGRICULTURAL SCIENCE DIGEST
practices significantly increased the growth parameters of blackgram. Maximum plant height at harvest was recorded for weed free treatment. Maximum pods per plant, seeds per pod, 1000 grain weight, grain, straw and maize equivalent yields were obtained from weed free plots which was at par witp metolachlor @ 1.0. kg ha,l but was superior to other weed co~ol treatments. Growth characters and yreld at-
tributes und~r observation and seed and straw yield of blackgram were more under 2:2 row planting system in comparison to 1: 1 system (Table 1). This might be due to the faGt that blackg.:am plants under 2: 2 rows planting systp.n1 were spaced on account of less frequent mterception by maize rows. Abbas et al. (1985) also reportel'.i similar results.
REFERENCES Abbas, M. et al. (1995). Indian J. Agric. Sci. 65: 34-38. Thakur, DR (1994). Indian J. Agron. 39: 203-206. Thakur, D.R. and Singh, KK. (1990). Indian J. Agric. Sci. 60:245-248.
