Weed management in rice, and rice-based cropping systems
Long-term herbicide trial in transplanted lowland rice-rice cropping system
TNAU, Coimbatore
Significantly higher grain yield and income was obtained with PE bensulfuron-methyl + pretilachlor 660 g/ha fb hand weeding. Whereas, in Kharif 2018 significantly higher grain yield and income were obtained with PE pyrasosulfuron-ethyl 20 g/ha fb hand weeding. The soil microflora and soil enzymes were reduced initially, howver it was gradually increased upto 10 times compared with hand weeding.
Long-term herbicidal trial in rice-rice cropping sequence
AAU, Jorhat
In the long-term herbicidal trial in rice-rice cropping sequence, the highest grain yield in autumn and winter rice was resulted by pyrazosulfuron 25 g/ha + 2,4-D 0.5 kg/ha rotated with pretilachlor 0.75 kg/ha (75% nutrient through fertilizers + 25 % nutrient through organic source) because of this treatment was found best in managing weeds.
Weed management and soil enrichment by concurrent growing of daincha in rice-rice-vegetable cropping system
KAU, Thrissur
Under this experimentation, at 45 DAS, significantly lower weed density of Isachne miliacea was observed in the hand weeded treatment and in rice- Daincha cha concurrent system in which daincha was incorporated manually, followed by hand weeding (Table 1). The total dry biomass accumulation of weeds and higher weed control efficiency (WCE) at 45 DAS was also found lower with the rice- Daincha concurrent system in which daincha was incorporated manually, followed by hand weeding treatment. Just after 45 DAS, very heavy rains and unpredicted flood occurred and the field was completely submerged for about a week, resulting in a completely different trend of weed dry matter production at 65 DAS. Hand weeding again recorded lowest value of dry matter, but the other treatments which were best at 45 DAS showed a reverse trend. Comparing weed density at 45 and 65 DAS, it was observed that at 65 DAS, there was a significant reduction in density of all species except that of Isachne miliacea and Ludwigia perennis, which probably could overcome complete prolonged submergence and still survive. Data on effect of treatments on grain yield showed that all treatments were on par except in the case of rice- Daincha concurrent system with Daincha incorporated manually and unweeded control, which registered significantly lower yields. Effect of treatments on straw yield was non-significant.
Table 1 Effect of different weed management practices on weed growth, crop yield and economics in rice-rice-vegetable cropping system (Kharif, 2018)
| Treatments | Weed density (no./m2) at 45 DAT | Weed dry matter production (kg/ha) at 45 DAS | WCE at 45 DAS | Grain yield (t/m2) | Straw yield (t/m2) | B : C ratio | |
| I. mileacea | M. vaginalis | ||||||
| Concurrent rice- Daincha, Daincha brown manured by 2,4-D at 25 DAS | 2.99
(9.33) |
1.48
(5.33) |
66.08
(47.7) |
35.66 | 2.22 | 2.715 | 1.06 |
| Rice- Daincha, Daincha brown manured by 2,4-D fb cyahalofop butyl at 25 DAS | 5.30
(28.00) |
0.22
(0) |
56.96
(32.4) |
44.54 | 2.05 | 2.20 | 0.89 |
| Rice- Daincha, Daincha brown manured by 2,4-D fb hand weeding at 45 DAS | 3.26
(10.67) |
0.22
(0) |
32.07
(10.7) |
68.78 | 2.41 | 2.66 | 0.85 |
| Rice- Daincha, dain Daincha cha incorporated manually at 25 DAS | 6.29
(40.00) |
2.91
(13.33) |
79.55
(66) |
22.55 | 1.42 | 1.81 | 0.62 |
| Rice- Daincha, Daincha incorporated manually at 25 DAS fb bispyribac-sodium | 6.68
(45.33) |
0.22
(0) |
96.71
(100.1) |
5.84 | 2.58 | 2.75 | 1.00 |
| Rice- Daincha, Daincha incorporated manually at 25 DAS fb hand weeding at 45 DAS | 2.77
(8.00) |
1.10
(2.67) |
24.21
(6.1) |
76.43 | 2.50 | 2.72 | 0.80 |
| Rice – hand weeded at 25 and 45 DAS | 2.29
(5.33) |
0.82
(1.33) |
30.24
(9.7) |
70.56 | 2.33 | 2.43 | 0.66 |
| Unweeded control | 6.63
(45.33) |
2.36
(8.00) |
102.71
(109.33) |
– | 1.92 | 2.87 | 1.02 |
| LSD(P=0.05) | 1.429 | NS | 3.38 | 0.561.99 | NS | ||
Note: Original figures in parentheses were subjected to square-root transformation before statistical analysis
Weed management in maize-based cropping system
Efficacy of pre and post emergence herbicides in maize
PDKV, Akola
The weed control treatments significantly reduced the weed density and weed biomass when compared with unweeded control (Table 2). Among the different weed management treatment, early post-emergence application of tembotrione +atrazine (120+500g/ha) fb IC + HW at 40DAS and topramezone +atrazine (25.2+500g/ha) fb IC + HW at 40DAS proves better in controlling weed density and dry matter accumulation at 60 DAS in maize. Maximum grain and straw yield at harvest was found in conventional practice i.e. IC + HW at 20 and 40 DAS, which was at par with atrazine 1 kg/ha fb HW at 40 DAS and post emergence herbicides + IWM treatment. The net return was found maximum under conventional practice followed by atrazine 1.0 Kg/ha PE fb HW at 40 DAS and tembotrione +atrazine (120+500g/ha) EPOE fb IC + HW at 40DAS. Whereas, the maximum B:C ratio (3.12) was found with atrazine 1.0 Kg/ha PE fb HW at 40 DAS and tembotrione +atrazine (120+500g/ha) EPOE fb IC + HW at 40DAS treatment in the same treatments and which closely followed by topramezone +atrazine (25.2+500g/ha) EPOE fb IC + HW at 40DAS treatment (3.11).
Table 2 Effect of different weed management treatments on weed growth, crop yield and economics in maize
| Treatments | Total weed density (No/m2) at 60 DAS | Total weed dry weight (g/m2) at 60 DAS | Grain yield (t/ha) | Straw yield (t/ha) | NMR
(Rs /ha) |
B:C Ratio |
| Atrazine 1.0 Kg/ha PE fb HW at 40 DAS | 3.47
(11.6) |
3.59
(12.3) |
4.63 | 7.00 | 49,970 | 3.12 |
| Atrazine + pendimethalin (0.50+0.25 Kg/ha) PE | 6.24
(38.4) |
5.06
(25.2) |
2.98 | 6.15 | 28,635 | 2.37 |
| Atrazine 1.0 Kg/ha PE fb 2,4-D 1.0 kg /ha LPoE | 4.71
(21.7) |
4.64
(21.1) |
3.53 | 6.41 | 35,970 | 2.69 |
| Atrazine + pendimethalin (0.50+0.25 Kg/ha) PE fb 2,4-D 1.0 kg /ha LPoE | 5.19
(26.4) |
4.93
(23.9) |
3.48 | 6.37 | 35,218 | 2.65 |
| Topramezone 25.2 g/ha EPoE | 5.42
(29.0) |
5.18
(26.3) |
3.38 | 6.26 | 33,454 | 2.57 |
| Tembotrione 120g /ha EPoE | 5.75
(32.5) |
5.57
(30.5) |
3.40 | 6.28 | 33,616 | 2.58 |
| Topramezone 25.2 g/ha EPoE fb IC +HW at 40DAS | 3.22
(9.89) |
2.49
(5.71) |
4.21 | 6.50 | 43,024 | 2.83 |
| Tembotrione 120g /ha EPoE fb IC +HW at 40DAS | 2.97
(8.35) |
2.49
(5.69) |
4.07 | 6.70 | 41,243 | 2.74 |
| Topramezone +atrazine (25.2+500g/ha) EPOE fb IC + HW at 40DAS | 2.61
(6.34) |
2.29
(4.75) |
4.38 | 6.86 | 44,976 | 3.11 |
| Tembotrione +atrazine (120+500g/ha) EPOE fb IC + HW at 40DAS | 2.76
(7.11) |
2.35
(5.01) |
4.58 | 6.98 | 47,655 | 3.12 |
| IC+HW at 20 and 40DAS | 2.34
(5.03) |
2.10
(3.94) |
4.87 | 7.30 | 50,852 | 2.75 |
| Weedy check | 13.28
(176.0) |
12.5
(157.1) |
1.99 | 5.64 | 15,863 | 1.81 |
| SE (m) + | 0.21 | 0.18 | 0.25 | 0.23 | 3,160 | — |
| LSD (P= 0.05) | 0.58 | 0.54 | 0.72 | 0.69 | 8,468 | — |
Note: PE: Pre-emergence; PoE: Post-emergence; EPoE: Early post-emergence; LPoE: Late post-emergence; IC: Intercultural operation; HW: Hand weeding; DAS: Days after sowing; fb: Followed by; Original figures in parentheses were subjected to square-root transformation before statistical analysis.
Evaluation of new post-emergent herbicides for weed control in maize
MPUAT, Udaipur
The most dominating weed species in experimental plot were Echinochloa colona and Setaria viridi. Weed density of monocot weeds were higher than dicot weeds. At 60 DAS, the lowest weed density and dry weight was recorded with pre- emergence application of atrazine 750 g/ha fb tembotrione 120 g/ha at 20 DAS over other treatments (Table 3). The maximum grain yield (5.24 t/ha) was recorded with pre-emergence application of atrazine 500 g/ha ha fb tembotrione 120 g/ha at 20 DAS which was statistically at par with two manual weeding at 15 & 35 DAS (5.21 t/ha). Atrazine 750 g/ha fb topramezone 25.2 g/ha at 20 DAS, atrazine 500 g/ha fb tembotrione 120 g/ha at 15-20 DAS, atrazine 500 g/ha fb topramezone 25.2 g/ha at 15-20 DAS and atrazine 500 g/ha + 2,4-D 800 g/ha statistically at par with each other in terms of grain yield. The maximum straw yield was recorded in pre-emergence application of atrazine 500 g/ha ha fb tembotrione 120 g/ha at 20 DAS over other treatments. The highest net returns (Rs. 70515/ha) and B C ratio (2.51) were realized with pre-emergence application of atrazine 500 g/ha ha fb tembotrione 120 g/ha at 20 DAS.
Table 3 Effect of different weed management treatments on weed growth, crop yield and economics in maize
| Treatments | E. colona density at 60 DAS | S. viridis density at 60 DAS | Total weed dry weight (No/m2) at 60 DAS | Grain Yield (t/ha) | Straw Yield (t/ha) | NMR
(Rs /ha) |
B:C Ratio |
| Atrazine 750 g/ha as PE | 3.10
(9.10) |
1.43
(9.10) |
18.67 | 3.82 | 5.02 | 48,651 | 1.99 |
| 2,4-D sodium salt 1000 g/ha at 15-20DAS | 6.91
(47.2) |
1.42
(47.2) |
49.04 | 3.23 | 4.96 | 38,362 | 1.55 |
| Tembotrione 120 g/ha at 15-20DAS | 3.10
(9.12) |
2.33
(9.12) |
15.08 | 3.19 | 5.27 | 36,111 | 1.33 |
| Topramezone 25.2 g/ha at 15-20DAS | 3.12
(9.25) |
1.28
(9.25) |
14.47 | 3.29 | 4.95 | 37,028 | 1.36 |
| Atrazine 750 g/ha PE fb 2,4-D sodium salt 1000 g/ha at 15-20DAS | 3.04
(8.72) |
0.78
(8.72) |
12.53 | 3.82 | 5.07 | 47,511 | 1.85 |
| Atrazine 750 g/ha PE fb tembotrione 120 g/ha at 15-20DAS | 1.47
(1.67) |
0.74
(1.67) |
2.85 | 5.24 | 6.05 | 70,515 | 2.51 |
| Atrazine 750 g/ha PE fb topramezone 25.2 g/ha at 15-20DAS | 1.58
(2.00) |
0.74
(2.00) |
3.35 | 4.96 | 5.70 | 65,195 | 2.32 |
| Atrazine 500 g/ha PE +2,4-D sodium salt 800 g/ha at 15-20DAS | 5.21
(26.7) |
1.06
(26.7) |
31.51 | 4.60 | 5.05 | 60,290 | 2.35 |
| Atrazine 500 g/ha PE + tembotrione 120 g/ha at 15-20DAS | 1.78
(2.67) |
1.17
(2.67) |
5.16 | 4.83 | 5.54 | 62,704 | 2.24 |
| Atrazine 500 g/ha PE + topramezone 25.2 g/ha at 15-20DAS | 1.96
(3.33) |
1.05
(3.33) |
6.56 | 4.64 | 5.38 | 59,206 | 2.11 |
| Manual weeding at 15 and 35 DAS | 2.41
(5.33) |
0.77
(5.33) |
9.29 | 5.21 | 5.21 | 52,023 | 1.17 |
| Weedy check | 7.33
(53.3) |
3.66
(53.3) |
82.11 | 2.37 | 4.01 | 23,970 | 1.04 |
| SE (m) + | 0.12 | 0.02 | 0.69 | 0.24 | 0.26 | – | – |
| CD P= 0.05 | 0.35 | 0.05 | 2.03 | 0.70 | 0.75 | – | – |
Note: PE: Pre-emergence; DAS: Days after sowing; Original figures in parentheses were subjected to square-root transformation before statistical analysis.
Weed management with new generation herbicides in maize (sweet corn)
OUAT, Bhubaneswar
In sweet corn, at 45 DAS, treatments like pre-emergence application of pendimethalin
(1 kg/ha) fb tembotrione (115 g/ha) and pre-emergence application of pendimethalin
(1 kg/ha) fb topramezone (25 g/ha) reported lowest weed population which differ significantly from remaining treatments in decreasing total weed population (Table 4). Whereas, at the same stage of maize crop, pre emergence application of pendimethalin (1kg/ha) fb tembotrione (115 g/ha) at 40 DAS, pre emergence application of pendimethalin (1kg/ha) fb topramezone (25 g/ha) at 40 DAS gave minimum weed dry weight. Both the treatments are significantly superior over the remaining treatments. Fresh kernel yield of sweet corn was significantly influenced due to different weed control treatments. All the weed control treatments recorded significantly higher cob yield than weedy check. Pre-emergence application of pendimethalin (1 kg/ha) fb topramezone (25 g/ha) at 40 DAS recorded higher fresh kernel yield (16.4 t/ha) over rest of the treatments. However, pre-emergence application of pendimethalin (1.0 kg /ha) fb tembotrione (115 g/ha) at 40 DAS (15.8 t/ha), pre-emergence application of pendimethalin (.0 kg/ha) fb 1 HW at 40 DAS (14.8 t/ha), pre-emergence application of atrazine (1.0 kg/ha) fb 1 HW at 40 DAS (14.3 t/ha) recorded higher yield which were at par with pendimethalin (1.0 kg/ha) fb topramezone (25 g/ha) at 40 DAS.
Table 4 Effect of different weed management treatments on weed growth, crop yield and economics in maize (sweet corn)
| Treatments | Total weed density (No/m2) at 45 DAS | Total weed dry weight (No/m2) at 45 DAS | Fresh kernel yield (t/ha) | Fresh cob yield (t/ha) | Green fodder yield (t/ha) |
| Atrazine 1.0 kg/ha PE fb HW at 40 DAS | 8.67(74.66) | 5.13(25.81) | 9.44 | 20.53 | 38.61 |
| Atrazine + pendimethaline (0.50 + 0.25 kg/ha) PE (tank mix) | 8.17(66.24) | 4.83(22.82) | 10.22 | 22.73 | 39.27 |
| Atrazine 1.0 kg/ha PE fb 2,4–D 1.0 kg/ha LPoE | 4.97(24.21) | 3.93(14.78) | 11.01 | 24.47 | 40.43 |
| Atrazine + pendimethaline (0.50 + 0.25 kg/ha) PE fb 2,4–D 1.0 kg/ha LPoE | 5.53(30.08) | 3.90(14.71) | 11.08 | 24.58 | 40.71 |
| Topramezone 25 g/ha EPoE | 2.01(3.57) | 1.42(1.54) | 14.27 | 31.72 | 45.37 |
| Tembotrione 100 g/ha EPoE | 1.97(3.42) | 1.26(1.33) | 14.82 | 32.94 | 45.83 |
| Topramezone 25 g/ha EPoE fb IC | 1.48(1.72) | 0.91(0.33) | 15.84 | 35.21 | 47.32 |
| Tembotrione 100 g/ha EPoE fb IC | 1.63(1.45) | 0.84(0.22) | 16.43 | 36.28 | 47.96 |
| Topramezone + atrazine (25 + 250 g/ha) EPoE fb IC | 2.08(3.85) | 1.43(1.54) | 12.05 | 28.47 | 42.57 |
| Tembotrione + atrazine (100+ 250 g/ha) EPoE fb IC + HW at 30 DAS | 15.2(230.54) | 10.97(119.84) | 5.45 | 12.13 | 23.48 |
| IC + HW at 20 and 40 DAS | 2.01(3.57) | 0.84(0.22) | |||
| Weedy check | 32.41(102.41) | 14.3(15.4) | |||
| SEm± | 0.22 | 0.08 | 1.75 | 1.89 | 1.70 |
| CD(P=0.05) | 0.53 | 0.19 | 4.30 | 4.63 | 4.17 |
Note: PE: Pre-emergence; PoE: Post-emergence; EPoE: Early post-emergence; LPoE: Late post-emergence; IC: Intercultural operation; HW: Hand weeding; DAS: Days after sowing; fb: Followed by; Original figures in parentheses were subjected to square-root transformation before statistical analysis.
Weed management in other cropping system
Herbicidal weed management in greengram
CCSHAU, Hisar
Experimental field was infested with Trianthema portulacastrum and Cyperus rotundus. All pre-emergence herbicide treatments proved effective against predominant weed T. portulacastrum but not against C. rotundus. Post-emergence application of aciflourfen + clodinafop at all the rates proved very effective against T. portulacastrum but its efficacy against C. rotundus was poor. Pyroxasulfone alone at 127.5 and 150 g/ha and its combination with pendimethalin proved effective against all weeds. Maximum plant dry matter accumulation and number of pods /plant were recorded under weed free treatment which was at par with aciflourfen + clodinafop at all rates and imazethapyr + pendimethalin at 1000 g/ha. Presence of weeds throughout the season caused 76 % reduction in seed yield of green gram. Seed yield was maximum (1.29 t/ha) with use of aciflourfen + clodinafop at 370 g/ha which was significantly at par with its lower dose, pyroxasulfone 150 g/ha, pyroxasulfone + pendimethalin, imazethapyr + pendimethalin at 1000 g/ha and weed free but significantly higher than all other treatments.
Integrated weed management in turmeric
PDKV, Akola
In the experimental field, both broad and narrow leaved weeds were observed but dominance of broad leaved weeds was observed in entire field. The weed control treatments significantly reduced the weed population and weed biomass when compared with unweeded control. At 60 DAS, treatment hand weeding (25, 45 & 75 DAP) recorded significantly lower weed count and dry matter accumulation followed by glyphosate fb 2 HW (45 & 75 DAP), pendimethalin 1 kg/ha (0-5 DAP) fb straw mulch 10 t/ha (10 DAP) fb one HW (75 DAP) and metribuzin 0.7 kg/ha (0-5 DAP) fb straw mulch (10 DAP) fb HW (75 DAP). At 60 DAS highest weed control efficiency (WCE) was recorded under metribuzin 0.7 kg / ha (0-5 DAP) fb straw mulch (10 DAP) fb HW (75 DAP) followed by post-emergence application of glyphosate fb 2 HW (45 & 75 DAP) followed by pendimethalin 1 kg/ha (0-5 DAP) fb straw mulch 10 t/ha (10 DAP) fb one HW (75 DAP). Number of leaves recorded more or less similar in most of the treatment while maximum number found with those treatments performed better in managing weeds. Maximum rhizome yield was observed in weed free treatment (23.88 t/ha) while among the IWM treatments application of pendimethalin 1 kg/ha (0-5 DAP) fb straw mulch 10 t/ha (10 DAP) fb one HW (75 DAP) recorded higher rhizome yield (22.72 t/ha) which was closely followed by metribuzin 0.7 kg/ha (0-5 DAP) fb straw mulch (10 DAP) fb HW (75 DAP). The higher net return and B:C ratio was also observed with these treatments.
Rice residue management to standardize the succeeding wheat crop
GBPUAT, Pantnagar
Present study envisaged the management of rice residue in a combine harvested field and its impact on wheat performance. Rice was harvested very close to the surface at 30 and 50 cm by combine and in all cases, loose straw left by combine was removed from the field (simulating as conditions created by Baler). In conventional tillage, double harrow + planking + rotavator + double harrow + planking and in reduced tillage harrow + planking + rotavator + harrow + planking were done to prepare land. In zero tillage, sowing was done at about 70% of field capacity moisture. The day on which sowing was done in zero tillage; the field preparation was started in other tillage systems. In the first year, grain yield was not influenced significantly by tillage systems and was comparable in all the tillage systems (Table 1.3.4.1(i). Numerically, reduced tillage managed to record maximum grain yield. Whereas, straw yield and harvest index both were influenced significantly by tillage systems. Reduced tillage recorded maximum straw yield and harvest index, which was comparable in all the tillage systems. Residue load did not influence grain and straw yield, and harvest index. Reduced tillage attained maximum yield due to better rhizospheric environment.
Management of complex weed flora in summer greengram
PAU, Ludhiana
Major weed flora in the field included Trianthema portulacastrum, Dactyloctenium aegyptium, Digitaria sanguinalis and Cleome viscosa. Application of sodium acifluorfen + clodinafop propargyl at 245 and 306 g/ha gave effective control of all weeds species which was significantly better than use of sodium acifluorfen, clodinafop-propargyl or pendimethalin alone. All weed control treatments gave significantly higher seed yield of greengram than unsprayed weedy check. Sodium acifluorfen + clodinafop propargyl at 245 and 306 g/ha gave the highest seed yield of greengram which was at par to weed free treatment.
Management of complex weed flora in rapeseed & mustard crops
PAU, Ludhiana
Cyperus rotundus was the major weed in the experimental field. Other weeds included Eleusine indica, Digitaria sanguinalis, Eragrostis tenella, Anagallis arvensis, Trianthema portulacastrum, Phylanthus niruri. Pre-emergence application of napropamide at 1125 and 1406 g/ha significantly reduced the density of all the weeds as compared to unsprayed check. Napropamide at all doses at 843, 1125 and 1406 g/ha significantly reduced biomass of grasses, broadleaves and sedges than unsprayed check; there was significant decrease in weed biomass with every increment of napropamide. The height and branches of crop plants did not vary significantly among weed control treatments. Application of napropamide at all levels significantly increased seed yield of toria as compared to unsprayed check; seed yield with napropamide at 1125 and 1406 g/ha were at par to weed free treatment. Herbicide was safe to the crop at doses tested.
Weed management in sugarcane
Evaluation of different herbicides in spring planted sugarcane
CCSHAU, Hisar
Weed flora of experiment consisted of Dactyloctenium aegyptium and Cynodon dactylon (grassy), Euphorbia microphylla (broad leaved weed-BLW) and Cyperus rotundus (sedge). At 45 DAS, all weed control treatments were very effective against grasses and broadleaf weeds. Treatments consisted of halosulfuron proved very effective against C. rotundus as is evident from density of sedges at 45 DAS. Inspite of three hoeing, density of Cyperus was more in this treatment due to regeneration in 3 days after hoeing. Sulfentrazone at 720 g/ha was fb hoeing fb metsulfuron/2,4-D was less effective in reducing density of total weeds particularly sedges. Similar trend in density of grassy, BLW and sedges was also observed at 60 DAS. Effect of halosulfuron in reducing density of C. rotundus remained consistent. None of the treatment affected the germination count and phytotoxicity on sugarcane crop (data not given). Early post emergence (15 DAP) use of glyphosate 40% SL at 1860 g/ha + metribuzin was more effective than paraquat fb atrazine in reducing total weed count.
Weed management in spring planted sugarcane
BCKV, Kalyani
The most dominating weeds were Cyperus rotundus and C. difformis as sedge, Cynodon dactylon as grassy weed and Alternanthera phyloxeroides, Physalis minima, Commelina benghalensis and cucumis sativus as broad leaved species. The minimum dominance of C. rotundus and C. dactylon was observed in the treatment having atrazine 1.0 kg/ha as PRE fb hand weeding at 30 DAS, and this treatment also reduces the total biomass of weeds to a greater extent. Regarding crop performance, highest value of biological yield was recorded in atrazine 1.0 kg/ha as PRE fb hand weeding at 30 DAS followed by sesbania co-culture fb 2, 4-D 1.0 kg/ha at 40 DAS and atrazine + pendimethalin (0.50 + 0.5 kg/ha) PRE fb hand weeding at 30 DAS. Yield components and yield as recorded in the experiment are presented in the below table showed that the treatment atrazine 1.0 kg/ha as PRE fb hand weeding at 30 DAS was the best performer and the second best one was the treatment sesbania co-culture fb 2, 4-D 1.0 kg/ha at 40 DAS. This threatments also gave higher net return and B:C ratio as compared to others treatments.
Weed management in orchards
CSKHPKV, Palampur
Integrated weed management in established peach orchard
The weed flora of the experimental field comprised of Alternanthera philoxeroides, Ageratum, Cynodon dactylon, Artemisia, Bidens pilosa, Trifolium repens, Plantago lanceolata, Setaria glauca and Polygonum. In the month of March major weed flora comprised of Ageratum, C. dactylon, Artemisia, T. repens and P. lanceolata. The population of Artemisia was highest followed by P. lanceolata, C. dactylon, T. repens and Ageratum. In the month of August major weed flora comprised of A. philoxeroides, Ageratum, C. dactylon, Artemisia, B. pilosa, S. glauca and Polygonum. The population of Ageratum was highest followed by A. philoxeroides, B. pilosa, C. dactylon, Artemisia, Polygonum and S. glauca. Results of the study revealed that maximum peach yield was recorded in legume intercropping treatment (7.74 t/ha) and which was at par with the manual weeding, fodder intercropping, application of glyphosate, while significantly lowest peach yield was recorded under unweeded situation due to abundance of weeds.
Weed management in fenugreek
MPUAT, Udaipur
Bioefficacy evaluation of different herbicides in fenugreek and their residual effect on succeeding crop
The prominent weed species in experimental field were Chenopodium album, Chenopodium murale, Fumeria parviflora, Malwa parviflora, Melilotus indica, Convolvulus arvensis and Phalaris minor.Weed density of broad leaf weeds were higher than grassy weeds at 60 DAS. The lowest weed density and total weed dry biomass accumulation at 60 DAS was recorded with PRE application of oxadiargyl 100 g/ha fb one hoeing at 40 DAS. And the maximum WCE (86.3%) was also recorded with the same treatment. Data indicated that the maximum seed yield (2908 kg/ha) was recorded with weed free treatment. Among herbicidal treatments PRE application of oxadiargyl 100 g/ha fb one hoeing at 40 DAS recorded the maximum seed yield (2820 kg/ha) which was significantly higher to other treatments. The lowest seed yield was recorded in weedy check (1.05 t/ha). The increment in seed yield due to PRE application of oxadiargyl 100 g/ha fb one hoeing at 40 DAS was 24.7 and 27.2 % higher over PRE application of imazethapyr fb one hoeing at 40 DAS and PRE application of oxadiargyl 100 g/ha. The highest net returns (Rs. 98,158/ha) and B C ratio (2.63) were realized with PRE application of oxadiargyl 100 g/ha fb one hoeing at 40 DAS.
Residual effect of herbicide on succeeding fodder maize
During fodder maize cultivation, major weeds observed in the experimental field were Echinochloa colona, Commelina bengalensis, Trianthama portalacastrum, Digera arvensis, Parthanium hysterophorus and Cyperus rotundus. Application of imazethapyr, pendimethalin, oxyfluorfen, oxadiargyl and imazethapyr + imazamox (RM) to fenugreek and its residual phytotoxic effect on succeeding fodder maize was not observed at 10 and 15 days after herbicide application, and there was no carry over or residual phytotoxic effect on succeeding maize fodder. All the weed control treatments adopted in preceding fenugreek crop had no significant impact in respect to dry matter accumulation of maize crop plant at 30 DAS and final green fodder yield.
Weed management in vegetable pea
Management of complex weed flora in vegetable peas and residual effect on succeeding cucurbit crops
SKUAST, Jammu
The most dominant weed species found in experimental field during crop growth period were mainly Vicia sativa, Anagallis arvensis, Melilotus indica and Medicago denticulata amongst broad leaved weeds and Phalaris mionr and Cynodon dactylon amongst grassy weeds. The weed management treatments had significant effect on weed density and weed biomass at 50 DAS (Table 1.3.10.1). Among the herbicidal treatments lower grassy, broad-leaved, sedges, total weed density and weed biomass were recorded in pendimethalin+imazethapyr 1250 g/ha as pre-emergence followed by pendimethalin+imazethapyr 1000 g/ha as pre-emergencee. Different weed management treatments had significant effect on growth, yield and yield attributes as compared weedy check. Among the weed management treatments, all the weed management treatments recorded significantly higher plant height, plant dry matter, number of nodules, number of pods and green pod yield as compared to weedy check. Among the herbicidal treatments, highest green pod yield was recorded with pendimethalin + imazethapyr 1250 g/ha as pre-emergencee followed by pendimethalin + imazethapyr 1000 g/ha. The highest net returns and B:C ratio was recorded in pendimethalin + imazethapyr 1000 g/ha. There was no residual phytotoxicity on succeeding cucurbit crops (Cucumber and Round Gourd).
Weed management in direct-seeded rice and wheat
Effect of irrigation methods and weed management on weed flora dynamics in direct- seeded rice and wheat
SKUAST, Jammu
During winter season, the main dominating weed flora were Phalaris minor and Avena spp. amongst grassy weeds; Rumex spp., Anagalis arvensis and Melilotus indica amongst broad-leaved weeds. Different irrigation treatments had no significant effect on weed density and weed biomass at 60 DAS and harvest. However, lower weed density and weed biomass were recorded in flooding irrigation as compared to sprinkler and sprinkler with VSD. Among the weed management treatments, all the weed management treatments recorded significantly lower weed density and weed biomass as compared to weed check. At 60 DAS, significantly lowest total weed density and biomass were recorded in sulfosulfuron + carfentrazone (25 + 20 g/ha) which was statistically at par with clodinafop-propargyl + metsulfuron (60 +4 g/ha) and significantly lower than other herbicidal treatments. Different irrigation treatments had non-significant effect on growth, yield attributes and grain and straw yield of wheat. However, higher growth, yield attributes, grain yield and straw yield of wheat were recorded in flooding irrigation as compared to sprinkler and sprinkler with VSD. All the weed management treatments recorded significantly higher growth parameters, yield attributes and grain and straw yield of wheat compared to weedy check. The higher grain yield and straw yield were recorded in clodinafop-propargyl+metsulfuron (60 +4 g/ha) which was statistically at par with sulfosulfuron+carfentrazone (25+20 g/ha) and clodinafop-propargyl +metribuzin (60+210 g/ha). The higher B: C ratio was recorded with flood irrigation as compared to sprinkle irrigation and sprinkler with VSD. However, highest water use efficiency was recorded with sprinkler with VSD as compared to sprinkler and flood irrigation. Amongst the weed management treatments highest B: C ration and water use efficiency were recorded with clodinafop-propargyl+metsulfuron (60 +4 g/ha) followed by sulfosulfuron+carfentrazone (25 + 20 g/ha) in wheat.