Analysis of compounds present in the basil oil sample by GC-MS Chromatogram-GC-MS analysis shows the high peak area% was Isolongifolo 26.57, Bulnesene 18.5, 3-Undecyne 9.14, Decanol 6.7, Betulin 5.62, and Eicosanoic acid 4.52. The camphor oil sample contained Ecogonin 35.97, Squalane 26,83, Octadecanoic acid, 4-hydroxy-, methyl ester 13.93, Bergenin 5.84, 1-Oleoyl-2-palmitoyl-rac-glycerol, Nonacosane, D-(+)-Camphor 2.5% Table (1 a and b). These compounds have allelopathic effects on weeds, (2), (13) and (6).
Table (2) data results pointed out that the number of weed species seedlings after applying the weed control treatments had a coefficient of variation (C.V.) less than the number of seedlings before applying the weed control treatments. Un-weeded control: the number of weed species seedlings increased during the period of the survey compared to the time before applying the weed control treatments. Applied essential oils significantly reduced the number of all weed species compared to the un-weeded control, except for the effect of basil oil on S. virides. These results were due to up-normal weed distribution in field experiments before application of the weed control treatments, but after application of the weed control treatments the number of weed/ m2 reduced by essential oil, which have a compounds have allelopathic activate was strong phytotoxic activity, (16). Essential oils contain a variety of volatile molecules, as antioxidants can be affecting inner cell membranes and mitochondrial dysfunction with their capacity to exert an antigen toxic effect, (2), (13) and (6).
Table (2) Effect of medicinal oil with adjuvant number of weed species (plant/m2) before and after application of essential oil treatments in 2020 wire house
Treatments
|
Setaria virides plant/m2
|
Echinochloa colonum plant/m2
|
Total grassy weeds plant/m2 plant/m2
|
Portulaca oleracea (Broad leaved ) plant/m2 plant/m2
|
Total weeds plant/m2
|
Before
|
After
|
Before
|
After
|
Before
|
After
|
Before
|
After
|
Before
|
After
|
Camphor oil
|
10.5
|
0.0
|
5.5
|
0.0
|
16.0
|
0.0
|
10.75
|
1.25
|
26.75
|
1.25
|
Basil oil
|
11.25
|
11.0
|
5.25
|
1.25
|
16.5
|
12.25
|
14.75
|
3.5
|
31.25
|
12.75
|
Un-weeded
|
4.0
|
6.25
|
4.25
|
10.5
|
8.25
|
16.75
|
5.0
|
7.25
|
13.25
|
24.0
|
L.sd 0.05
|
12.75
|
4.11
|
13.36
|
5.95
|
22.93
|
7.66
|
14.71
|
3.51
|
29.27
|
5.4
|
C.V.
|
92.5
|
27.1
|
154.5
|
27.7
|
97.6
|
34.3
|
83.6
|
24.4
|
71.5
|
11.8
|
The dominant weed species are recorded in Tables (3 and 4), and Fig. (1) shows the relative importance value of the weed species Ipomea eriocarpa (50.6 and 9.9 and 40.3%), Setaria virids (28.0 and 58.3 and 9.6%), Trianthema portulacastrum (7.3 and 17.7 and 40.7%) and Cynodon dactylon (0.0 and 11.3 and 22.4%) in wire house and field experiments during 2020, 2021 and 2022 seasons, respectively.
Tables (3 and 4) and Fig (2) show that all weed control treatments caused a significant reduction in the fresh weight of all species of weed in the wire house and field experiments. Hand hoeing and Adengo herbicide had a superior effect than essential oils on the total weeds. Camphor oil was effective on Cyperus rotundus, S. virids, Echinochloa colonum, and I. eriocarpa , which caused the reeducation in fresh weight of these weed species between 70-100%, compared to un-weeded check. Sweet basil oil was effective on C. rotundus, which caused the reducation the fresh weight by 65-80%. Essential oils were had less effect on T. portulacastrum. These results were due to the effects of essential oils, monoterpenes, camphor, apinene, and limonene, all of which strongly affected respiratory activity, (17).
Table (3) Effect of medicinal oil with adjuvant on weed species weight (g/m2) wire house experiment
Treatments
|
Setaria virides g/m2
|
Echinochloa colonum g/m2
|
Portulaca
|
Trienatum
|
Convolvulus
|
Ipomea
|
Corchorus
|
Camphor oil
|
67.2
|
7.5
|
11.0
|
90.0
|
15.8
|
98.7
|
0.0
|
Basil oil
|
220.2
|
11.8
|
6.7
|
85.5
|
9.5
|
49.0
|
0.0
|
Adengo extra
|
11.2
|
0.0
|
0.0
|
42.0
|
0.0
|
0.0
|
0.0
|
Hand hoeing
|
5.0
|
3.8
|
30.0
|
0.0
|
3.5
|
42.0
|
0.0
|
Un-weeded
|
378.0
|
42.0
|
39.3
|
98.6
|
26.5
|
684.0
|
83.3
|
L.sd 0.05
|
144.3
|
13.4
|
2.5
|
13.6
|
8.2
|
18.3
|
4.3
|
C.V.
|
68.7
|
66.9
|
9.2
|
9.3
|
50.1
|
6.8
|
16.7
|
Setaria virids was significantly reduced in fresh weight due to the treatments for weed control under study. The reduction percent in fresh weight in wire house and field experiments in 2021 and 2022 seasons was about 82.2, 87.4 and 83.2% with camphor oil treatment, 41.7, 100 and 61.6% with basil oil, 97, 80.3 and 97% with adengo herbicide and 98.6, 86.1 and 98.6% with hand hoeing twice, respectively, compared to un-weeded check.
E. colonum fresh weight reduced significantly by applied the weed control treatments. The fresh weight reduction was about 82.1, 71.1 and 33% with camphor oil, 71.9, 54.5 and 68.3% with basil oil, 100, 100 and 100% with adengo herbicide and 91, 100 and 100% with hand hoeing twice under wire house and field experiments in 2021 and 2022 seasons, respectively, compared to un-weeded check.
I. eriocarpa was affected by the essential oils under study with a lower density in the wire house and field experiments in 2021 which reduced fresh weight by 85.7 and 57.6% with camphor oil and 92.8 and 38.3% with basil oil, respectively. Under high infestation by I. eriocarpa in the 2022 season field experiment, the fresh weight was reduced by about 41.8% with camphor oil, 58% with basil oil and 52.7% with adengo herbicide. These results were due to the effects of essential oils, monoterpenes, camphor, apinene, and limonene, all of which strongly affected respiratory activity, (17).
T. portulacastrum was less affected by essential oils, the decrease in fresh weight in the wire house and two field experiments in the 2021 and 2022 seasons was about 8.7, 17.4 and 0.0% with camphor oil and 13.3, 43.4 and 26.6% with basil oil, compared to 57.4, 95.1 and 94.6% with adengo herbicide, respectively. These results were due to the effects of essential oils, monoterpenes, camphor, apinene, and limonene, all of which strongly affected respiratory activity, (17).
Table (4) Effect of medicinal oil with adjuvant on weed species weight (g/m2) field experiment in 2021 and 2022 seasons
Treatments
|
Setaria virides g/m2
|
Echinochloa colonum g/m2
|
Trienatum
|
Ipomea
|
Convolvulus
|
Cyperace
|
Cynodon
|
2021 season
|
Camphor oil
|
259.7
|
12.7
|
516.8
|
148.5
|
0.0
|
16.0
|
199.7
|
Basil oil
|
0.0
|
20.0
|
354.3
|
215.0
|
2.7
|
8.7
|
145.3
|
Adengo extra
|
404.7
|
0.0
|
30.8
|
106.0
|
0.0
|
7.6
|
27.0
|
Hand hoeing
|
285.7
|
0.0
|
16.5
|
0.0
|
0.0
|
17.0
|
0.0
|
Un-weeded
|
2056.3
|
44.0
|
626/0
|
348.3
|
10.3
|
44.6
|
400.3
|
LSD 0.05
|
84.3
|
7.9
|
76.7
|
44.9
|
1.1
|
3.1
|
6.5
|
C.V.
|
6.6
|
23.3
|
16.1
|
17.2
|
27.6
|
11.6
|
12.7
|
2022 season
|
Camphor oil
|
63.3
|
258.0
|
641.8
|
918.7
|
-
|
0.0
|
92.0
|
Basil oil
|
145.3
|
122.3
|
404.2
|
663.0
|
-
|
21.7
|
41.0
|
Adengo extra
|
11.3
|
0.0
|
30.8
|
746.7
|
-
|
9.0
|
78.5
|
Hand hoeing
|
5.0
|
0.0
|
16.5
|
100.0
|
-
|
11.5
|
163.0
|
Un-weeded
|
378.0
|
385.0
|
551.0
|
1579.8
|
-
|
147.5
|
877.8
|
LSD 0.05
|
21.3
|
18.3
|
204.3
|
65.6
|
-
|
28.0
|
51.8
|
C.V.
|
11.5
|
7.2
|
40.3
|
5.5
|
-
|
54.2
|
10.9
|
Table (5) and Fig (2) reflect the efficiency of weed control treatments under high infestation by weeds (high weed seed bank of the soil). The number of weed species seed bank of the soil at 0-5 and 6-15 cm depth seeds/m2 in the field experiment was (18263.3 and 2658) for I. eriocarpa, T. portulacastrum (17100.3 and 3217.6), Euphorbia geniculata (11615 and 5742.6), E. colonum (5921.8 and 3483.1), and S. virids (1227.4 and 938.1 seeds/m2). The greatest fresh weight reduction of total annual weed resulted from hand hoeing twice, followed by Adengo herbicide, sweet basil and camphor oils. Sweet basil and camphor oils were effective on E. geniculata and E. colonum, reducing fresh weight 100%, but less effective on I. eriocarpa. Basil oil and Adengo herbicide were more effective on S. virids than hand hoeing twice and camphor oil in this study.
Setaria virids, E. colonum and their total grassy weeds were significantly reduced in fresh weight due to the treatments for weed control under study, the reduction percent in fresh weight was about 7.9, 100 and 87.4% with camphor oil treatment, 100, 100 and 199% with basil oil, 100, 76.7 and 82.3% with adengo herbicide and 1.3, 100 and 86.5% with hand hoeing twice, respectively, compared to un-weeded check.
E. geniculata and I. eriocarpa and their total broad leaved weeds fresh weight reduction by 100, 0.0 and 0.0% with camphor oil, 100, 0.0 and 0.0% with basil oil, 0.0, 14 and 40% with adengo herbicide and 0.0, 100 and 95% with hand hoeing twice, respectively, compared to un-weeded check.
Table (5) Effect of medicinal oil with adjuvant on annual weed species complex weight (g/m2) field experiment under high soil weed seed banks in 2021 and 2022 seasons
Treatments
|
S. virides g/m2
|
E. colonum g/m2
|
Total grassy
|
T. portulacasterum
|
E. geneculata
|
Ipomea
|
Total broad leaved
|
Total annual weeds
|
2021 season
|
Camphor oil
|
359.7
|
0.0
|
359.7
|
916.7
|
0.0
|
1848.7
|
2765.0
|
3125.0
|
Basil oil
|
0.0
|
0.0
|
0.0
|
643.0
|
0.0
|
2015.9
|
2658.0
|
2658.0
|
Adengo extra
|
0.0
|
504.7
|
504.7
|
748.7
|
176.3
|
204.0
|
1127.0
|
1632.0
|
Hand hoeing
|
385.7
|
0.0
|
385.7
|
0.0
|
143.67
|
0.0
|
144.0
|
529.0
|
un-weeded
|
390.7
|
2165.3
|
2856.0
|
1584.3
|
54.0
|
237.3
|
1876.0
|
4432.4
|
LSD 0.05
|
34.66
|
78.2
|
84.3
|
98.9
|
19.93
|
48.56
|
125.6
|
149.7
|
C.V.
|
12.4
|
7.8
|
6.6
|
6.7
|
14.1
|
3.0
|
9.3
|
3.3
|
Seed banks in soil (seed m-2)
|
0-5 cm
|
1227.4
|
5921.8
|
7149.2
|
17100.3
|
11615.0
|
18263.3
|
46975.6
|
54124.8
|
6-15 cm
|
938.1
|
3483.1
|
4421.2
|
3217.6
|
5742.6
|
2658.0
|
11618.2
|
16039.4
|
Total annual weeds fresh weight reduction by 29.4, 40, 63.2 and 88.1% with camphor oil, basil oil, adengo herbicide hand hoeing twice, respectively, compared to un-weeded check. These results were due to the fact that I. eriocarpa had a high seed bank in the soil, which represented and germinated after applying the oils treatments as well as after killing the sensitive weed species and becoming the dominant weed species in the oils-treated plots. These results were in agreement with those obtained by (14), (13), (6), and (12).
Wire house experiments
All tested treatments significantly reduced the fresh weight of broadleaved, grassy and total weeds in the three seasons (2020, 2021 and 2022), as shown in table (6).
Results in Table (6), showed that the camphor oil caused the highest decrease in the fresh weight of broadleaved, grassy and total weeds which were (83.8%, 62.6% and 69.1%) and (71.4%, 72.3% and 72.0%) for the 2020 and 2021 seasons, respectively, compared to the un-weeded treatment. Basil oil treatment decreased the fresh weight of broadleaved, grassy and total weeds by (73.9%, 57.3% and 62.4%) and (50.8%, 68.8% and 61.7%) for the 2020 and 2021 seasons, respectively, compared to the un-weeded treatment.
In the 2022 season, the highest reductions in the fresh weight of broadleaved, grassy and total weeds were 94.5, 94.9 and 94.6%, respectively, recorded with Adengo herbicide treatment, followed by hand hoeing treatment (95.2, 93.1 and 94.4%, respectively), basil oil treatment (50.0, 58.6 and 53.3%, respectively) and Camphor oil treatment (18.3, 85.9 and 45.0%, respectively) compared to the un-weeded check. These results are due to the killing of the weeds by weed control treatments under studies due to phytotoxic activity on weed species and cutting the weed above the ground surface by hand hoeing, (2), (13), (6), (16) and (12).
Table (6) Effect of medicinal oil with adjuvant fresh weight (g/m2) of broadleaved, grassy and their total weeds in 2020, 2021 and 2022 seasons in wire house and field experiments.
Treatments
|
Fresh weight g/m2 of broad leaved weeds
|
Fresh weight g/m2 of grassy weeds
|
Fresh weight g/m2 of total weeds
|
2020
|
2021
|
2022
|
2020
|
2021
|
2022
|
2020
|
2021
|
2022
|
|
Wire house experiments
|
Camphor oil
|
60.5
|
139.0
|
528.5
|
314.3
|
205.5
|
59.3
|
374.8
|
344.0
|
587.3
|
Basil oil
|
97.5
|
239.3
|
323.8
|
358.5
|
232.0
|
174.0
|
456.0
|
471.3
|
497.8
|
Adengo herbicide
|
-
|
-
|
35.8
|
-
|
-
|
21.3
|
-
|
-
|
57.1
|
Hand hoeing twice
|
-
|
-
|
31.0
|
-
|
-
|
28.8
|
-
|
-
|
59.8
|
un-weeded
|
373.0
|
486.0
|
647.0
|
840.0
|
743.0
|
420
|
1213.0
|
1229.0
|
1067.0
|
L.sd 0.05
|
65.7
|
198.2
|
175.2
|
230.4
|
95.3
|
143.7
|
262.8
|
86.6
|
232.8
|
C.V.
|
21.4
|
25.6
|
29,8
|
26.4
|
14.0
|
31.3
|
22.3
|
7.35
|
25.8
|
|
Field experiments
|
Camphor oil
|
-
|
532.5
|
917.7
|
-
|
75.0
|
359.7
|
-
|
607.5
|
1276.3
|
Basil oil
|
-
|
313.8
|
653.0
|
-
|
232.0
|
0.0
|
-
|
545.8
|
643.0
|
Adengo herbicide
|
-
|
30.8
|
920.5
|
-
|
11.2
|
504.7
|
-
|
42.0
|
1427
|
Hand hoeing twice
|
-
|
20.0
|
215.5
|
-
|
8.8
|
385.7
|
-
|
28.8
|
529.3
|
un-weeded
|
-
|
653.0
|
1335.8
|
-
|
420.0
|
2165.3
|
-
|
1073.0
|
3803.7
|
L.S.D. 0.05
|
-
|
102.2
|
538.0
|
-
|
167.3
|
56.3
|
-
|
181.4
|
90.4
|
C.V.
|
-
|
21.4
|
43.3
|
-
|
72.7
|
5.4
|
-
|
25.6
|
3.82
|
Field experiments
All tested treatments significantly reduced the fresh weight of broadleaved, grassy and total weeds in the two seasons (2021 and 2022), shown in table (6).
In the 2021 season, the highest reductions in fresh weight of total weed were 97.3% and 96.1% recorded with hand hoeing and Adengo herbicide treatments, respectively, without significant difference between the two treatments, followed by 49.1% and 43.4% recorded with camphor oil and basil oil treatments, respectively, also without any significant difference between the two treatments compared to the un-weeded check.
In the 2022 season, the highest reductions in fresh weight of broadleaved, grassy and total weeds were (83.9, 82.2 and 86.1%) recorded with hand hoeing treatment, followed by (54.1, 100 and 83.1%) with camphor oil treatment, (31.3, 83.4 and 66.4%) with basil oil treatment and (31.1, 76.7 and 62.5%) with Adengo herbicide treatment, compared to un-weeded check. These results were due to the effect of herbicide and essential oils on the inhibitory carotenoid and DNA synthesis in the root meristem which caused the killing of the weed plant, These results were agreement with the obtained by (13), (6) and (16).
Effect of essential oils on cell of root and stem strictures
The transverse sections of stem and root of dicot weeds Chenopodium mural and Phalaris paradoxa as monocot, in the control plant presented the well-known anatomic regions. The zones identified in the mean roots transverse section were the root hairs zone, epidermis, cortex, xylem, xylem ray and phloem. The root hairs and cortex region were less and very thickened in the plant under basil and camphor oils treatments compared to the plants in un-weeded control, (8).
The effect of the two essential oils caused great anatomical changes, as appeared in transverse sections of the roots and stem of both Chenopodium mural and Phalaris paradoxa plants, as shown in Fig 4.
Cells of the epidermis, cortex and stele shapes had irregular and decreased numbers of xylem and epidermis layers, accompanied by inhibition of root formation due to changes in the hormone balance, particularly auxin, ethylene and gibberellin, which affected cell specification, proliferation and expansion of the two studied species, (13).
Essential oils caused epidermal necrotic the area cells of the cortex with the small cell size and compaction in its cell layers, which were inhibited as compared with untreated check. The anatomical abnormalities in the stem or root's cross section and decreased cell division that were induced by essential oils defense in both roots and stems of Chenopodium mural and Phalaris paradoxa plants, as compared with those of the untreated check it may be inhibited respiration, (17), (2), (5) and (13).
C. mural plant in control, the xylem parenchyma tissue forms in the stems, which gives support to the growing organs, but the effect of essential oils on the stem cross section presented an increased in pith size and less parenchyma tissue. These results are due to the exertion of antigen-toxic effects and changes in intracellular redox potential and mitochondrial dysfunction induced by essential oils (17), (2), (5) and (13).
The tested chemicals of cinnamic acid inhibited root hairs and changed the structure of the vascular system; the phloem elements were the most affected (8). Squalene content of some vegetable oils, Nergiz and Çelikkale (2011). Cinnamic acid chemical treatments were effective on the growth of bean plants, the biosynthesis of polyphenols and the growth of roots in the seedling stage at a concentration of 114.6 μg/cm2, (7). Essential oils (EOs) and their components, mainly terpenes, terpenoids, genranyl, phenol and squalene, cause changes in the structure of the vascular system, interact with the mitochondrial membrane and impair mitochondrial respiration directly, (17), (7), (8) and (13).
Wire house experiment: Table (7)
In the 2021 season, the treatments significantly affected the maize plant height, number of leaves/plant, ear weight and ear length, in which the highest values of plant height and number of leaves/plant (162.5 cm and 14.3, respectively) were recorded with camphor oil treatment, whereas the highest values of ear weight and ear length (140.7 g and 22.6 cm, respectively) were recorded with basil oil treatment, compared with un-weeded treatment.
In the 2022 season, the treatments had a significant effect on ear weight and length, with the highest ear weight (155.7g) recorded with basil oil treatment and the highest ear length (22.6 cm) recorded with camphor oil treatment, compared with un-weeded treatment, while the oils under study had no significant effect on maize plant height or number of leaves/plant. These results are due to the reduced maize/weed competition during the early stage of the maize plant and increased vegetative growth due to the decreased weed competition by weed control treatments and increased fertility elements around the maize root, (13).
Field experiment: Table (7)
In the 2021 season, the treatments significantly affected the maize plant height, number of leaves/plant, ear weight and ear length.
The highest value of plant height (252.9 cm) was recorded with hand hoeing treatment, followed by camphor oil, Adengo herbicide, un-weeded and basil oil treatments (242.8, 140.0, 235.0 and 232.0 cm, respectively).
The highest number of leaves/plant (14.0) was recorded with camphor oil treatment, followed by Adengo herbicide, hand hoeing, basil oil and un-weeded treatments (13.5, 13.5, 13.5 and 12.3, respectively). These results are due to the reduced maize/weed competition during the early stage of the maize plant and increased vegetative growth due to the decreased weed competition by weed control treatments and increased fertility elements around the maize root, (13).
The highest ear weight (163.4 g) was recorded with the camphor oil treatment, followed by hand hoeing, Adengo herbicide, basil oil and un-weeded treatments (162.5, 160.8, 134.1 and 128.0 g, respectively).
The highest ear length (25.0 cm) was recorded with Adengo herbicide, followed by camphor oil, hand hoeing, basil oil and un-weeded (24.3, 24.3, 21.8 and 20.0 cm, respectively).
In the 2022 season, the treatments significantly affected the maize plant height, ear weight and ear length, but the treatments had no significant effect on the number of leaves/plant.
The highest value of plant height (248.0 cm) was recorded with basil oil treatment, followed by Adengo herbicide, hand hoeing, camphor oil and un-weeded treatments (247.3, 238.0, 224.0 and 217.0 cm, respectively).
The highest ear weight (161.5 g) was recorded with the hand hoeing treatment, followed by basil oil, Adengo herbicide, camphor oil and un-weeded treatments (156.5, 156.3, 142.5 and 79.3 g, respectively).
The highest ear length (22.6 cm) was recorded with camphor oil, followed by Adengo herbicide, hand hoeing, basil oil and un-weeded (20.6, 20.5, 19.5 and 15.1 cm, respectively). These results are due to the increased maize growth characteristics and the increased competitive crop due to killing weeds in the early stages of maize growth. These results were in agreement with the results obtained by (13).
Table (7): Effect of medicinal oil with adjuvant on growth characters of maize in the 2021 and 2022 seasons in wire house and field experiments
Treatments
|
Plant height cm
|
Number of leaves/plant
|
ear weight g
|
Ear length cm
|
2021
|
2022
|
2021
|
2022
|
2021
|
2022
|
2021
|
2022
|
Wire house experiments
|
Camphor oil
|
279.0
|
260.0
|
14.8
|
14.5
|
134.1
|
136.1
|
19.6
|
22.6
|
Basil oil
|
260.5
|
261.5
|
14.3
|
14.5
|
140.7
|
155.7
|
22.6
|
15.1
|
un-weeded
|
243
|
259.5
|
13.0
|
14.1
|
83.5
|
89.1
|
15.1
|
15.1
|
L.sd 0.05
|
11.6
|
N.S
|
1.2
|
N.S
|
39.5
|
66.2
|
1.47
|
1.6
|
C.V.
|
2.58
|
4.1
|
4.9
|
5.1
|
19.14
|
30.0
|
10.2
|
4.7
|
Field experiments
|
Camphor oil
|
242.8
|
224.5
|
14.0
|
13.7
|
163.4
|
142.5
|
24.3
|
20.6
|
Basil oil
|
232.0
|
248.0
|
13.3
|
12.5
|
134.1
|
156.5
|
21.8
|
19.5
|
Adengo herbicide
|
240.0
|
247.3
|
13.5
|
13.5
|
160.8
|
156.3
|
25.0
|
20.6
|
Hand hoeing twice
|
252.9
|
238.0
|
13.5
|
13.8
|
162.5
|
161.5
|
24.3
|
20.5
|
un-weeded
|
235.0
|
217.0
|
12.3
|
13.8
|
128.0
|
79.3
|
20.0
|
15.1
|
L.S.D. 0.05
|
14.6
|
20.4
|
1.0
|
N.S.
|
26.4
|
34.8
|
1.5
|
1.4
|
C.V.
|
3.9
|
5.7
|
5.0
|
7.3
|
11.4
|
16.2
|
4.2
|
4.5
|
Table (8):
Wire house experiment:
In the 2021 season, the tested treatments had no significant effect on ear diameter, the number of rows/ear or the number of kernals/row.
In the 2022 season, the treatments had a significant effect on ear diameter, the number of rows/ear and the number of kernals/row. The camphor oil treatment gave the highest values for ear diameter and number of kernals/row (7.2 cm and 23.9), while the greatest number of rows/ear (12.9) was recorded with basil oil compared with the un-weeded treatment. The maize yield ton ha-1 was significantly affected by the tested treatments in the two seasons.
In the 2021 season, the greatest yield (5.9 ton ha-1) was recorded with basil oil treatment, followed by camphor oil treatment, which was 4.6 ton ha-1, which means that basil oil and camphor oil treatments increased in maize yield by 90.3% and 46.2%, respectively, compared to the un-weeded yield (3.1 ton ha-1).
In the 2022 season, the greatest yield (5.7 ton ha-1) was recorded with camphor oil treatment followed by Basil oil treatment which was 4.9 ton ha-1, which means that camphor oil and basil oil treatments increased in maize yield by 62.7% and 44.1%, respectively, compared to the un-weeded yield (3.4 ton ha-1).
Field experiment: concerning data in Table (8)
The tested treatments had a significant effect on ear diameter, the number of rows/ear, the number of kernals/row and grain yield ton ha-1 in the two seasons.
In the 2021 season, the highest ear diameter (8.4 cm) was recorded with Adengo herbicide, followed by hand hoeing (7.9 cm), camphor oil, basil oil treatments (7.7 cm) and un-weeded (6.4 cm).
The highest number of row/era (15.8) was recorded with basil oil treatment, followed by Adengo herbicide (15.5), hand hoeing (15.3), camphor oil (14.9) and un-weeded (11.4).
The highest number of kernals/row (45.5) was recorded with hand hoeing treatment, followed by camphor oil (43.3), Adengo herbicide (42.0), basil oil (41.3) and un-weeded (33.0).
In the 2022 season, the highest ear diameter (8.6 cm) was recorded with hand hoeing, followed by Adengo herbicide (7.8 cm), camphor oil, basil oil treatments (7.2 cm) and un-weeded (6.9 cm).
The highest number of row/era (15.4) was recorded with hand hoeing treatment, followed by Adengo herbicide (13.6), basil oil (12.2), un-weeded (11.9) and camphor oil (11.1).
The highest number of kernals/row (39.4) was recorded with hand hoeing treatment, followed by Adengo herbicide (34.8), camphor oil (31.0), basil oil (26.2) and un-weeded (23.5).
In the 2021 season, the greatest yield (6.7 ton ha-1) was recorded with basil oil treatment, followed by camphor oil (6.4 ton ha-1), Adengo herbicide (6.3 ton ha-1), hand hoeing (6.0 ton ha-1) and un-weeded (5.4 ton ha-1), which means that basil oil and camphor oil treatments increased maize yield by 23.8% and 18.8%, respectively, compared to the un-weeded yield (5.4 ton ha-1).
In the 2022 season, the greatest yield (10.2 ton ha-1) was recorded with hand hoeing treatment, followed by Adengo herbicide (9.5 ton ha-1), camphor oil (8.7 ton ha-1), basil oil treatment (8.3 ton ha-1), and un-weeded (5.0 ton ha-1). These results are due to the increase in ear weight and diameters, the number of kernals/row and the number of row/ear.
Table (8): Effect of medicinal oil with adjuvant on yield and yield components of maize in the 2021 and 2022 seasons in wirehouse and field experiments
Treatments
|
Ear diameters cm
|
Number of row/ear
|
Number of kernals/row
|
Grain yield ton ha-1
|
|
2021
|
2022
|
2021
|
2022
|
2021
|
2022
|
2021
|
2022
|
Wire house experiments
|
Camphor oil
|
6.4
|
7.2
|
9.9
|
12.7
|
24,1
|
23.9
|
4.6
|
5.7
|
Basil oil
|
5.8
|
7.2
|
9.6
|
12.9
|
25.7
|
20.9
|
5.9
|
4.9
|
un-weeded
|
6.5
|
6.9
|
9.5
|
9.6
|
20.9
|
16.0
|
3.1
|
3.4
|
L.sd 0.05
|
N. S.
|
1.1
|
N. S.
|
1.8
|
N. S.
|
6.7
|
2.4
|
0.4
|
C.V.
|
8.5
|
8.7
|
18.0
|
8.8
|
26.7
|
26.7
|
20.2
|
6.2
|
Field experiments
|
Camphor oil
|
7.7
|
7.2
|
14.9
|
11.1
|
43.3
|
31.0
|
6.4
|
8.7
|
Basil oil
|
7.7
|
7.2
|
15.8
|
12.2
|
41.3
|
26.2
|
6.7
|
8.3
|
Adengo herbicide
|
8.4
|
7.8
|
15.5
|
13.6
|
42.0
|
34.8
|
6.3
|
9.5
|
Hand hoeing twice
|
7.9
|
8.6
|
15.3
|
15.4
|
45,5
|
39.4
|
6.0
|
10.2
|
Un-weeded
|
6.4
|
6.9
|
11.4
|
11.9
|
33.0
|
23.5
|
5.4
|
5.0
|
L.S.D. 0.05
|
0,8
|
0.9
|
1.4
|
2.6
|
6.1
|
6.95
|
0.5
|
1.4
|
C.V.
|
6.9
|
7.9
|
6.2
|
13.2
|
9.7
|
14.6
|
5.1
|
17.3
|
Results in table (9) show that all test treatments had a significant effect on the fresh weight of broadleaved, grassy and total weeds and sunflower growth traits, yield and yield components.
The highest reduction in fresh weight of broadleaved, grassy and total weeds was recorded (71.4, 72.4 and 71.9%) with camphor oil treatment, followed by (50.7, 68.8 and 61.7%) with basil oil treatment, compared to un-weeded check. These results are due to the essential components of terpenoids, either as pure natural compounds or in mixtures, having a great effect on their structural and strong phytotoxic activity, (13) and (16).
Results in table (9) showed that sunflower yield was significantly affected by the tested treatments in which the highest yield (4.3 ton ha-1) was recorded with the camphor oil treatment, followed by the basil oil treatment, which gave a yield of about (4.0 ton ha-1) which means that using basil oil and camphor oil for weed control in sunflower caused an increase in yield of 90.9% and 63.6%, respectively, compared with an un-weeded yield (2. ton ha-1).
All tested components had no significant effect on head weight and diameter, or 100-seed weight, where the highest values of the previous parameters were recoded with camphor and basil oil treatment.
Table (9) Effect of medicinal oil with adjuvant fresh weight (g/m2) of broad leaved, grassy and total weeds, yield and yield components of sun flower 2022 seasons.
Treatments
|
Fresh weight g/m2 of weeds
|
Sunflower yield and yield component
|
Broad leaved weeds
|
Grassy weeds
|
Total weeds
|
Head weight g/head
|
Head diameters cm
|
100 seed weight g
|
Seed yield ton ha-1.
|
Camphor oil
|
139.0
|
205.5
|
344.5
|
312.1
|
15.9
|
9.4
|
4.3
|
Basil oil
|
239.3
|
232.0
|
471.2
|
302.0
|
15.5
|
9.0
|
4.0
|
Un-weeded
|
485.5
|
743.5
|
1229.0
|
216.1
|
13.1
|
8.5
|
2.6
|
L.S.D. 0.05
|
80.8
|
95.3
|
86.6
|
N. S.
|
N. S.
|
N. S.
|
1.5
|
C.V.
|
16.2
|
14.0
|
7.3
|
24.0
|
12.0
|
11.7
|
21.9
|
Results in tables (10 and 11) indicated that all test treatments had a significant effect on the fresh weight of broadleaved, grassy and total weeds and sorghum growth traits, yield and yield components, except synthetic herbicide were have high phytotoxity on sorghum plant.
The highest reduction in fresh weight of broadleaved, grassy and total weeds was recorded (91.1, 100 and 94%) with hand hoeing twice treatment, followed by (93.1, 68.2 and 85.1%) with basil oil treatment and (86.4, 33 and 69.1%) with camphor oil treatment compared to un-weeded check. These results are due to the fact that essential oils can act as prooxidants, affecting inner cell membranes and organelles such as mitochondria, depending on type and concentration, changes in intracellular redox potential and mitochondrial dysfunction induced by essential oils can be associated with their capacity to exert antigen-toxic effects. (2). Inhibition of carotenoid biosynthesis gives rise to chlorosis of new growth and effects on meristemtic regions, which become chlorotic and necrotic, followed by general foliar chlorosis and necrosis, but hand hoeing kills weeds by cutting the growing weeds above or below the soil surface.
Table (10) Effect of medicinal oil with adjuvant fresh weight (g/m2) of broadleaved, grassy and total weeds and sorghum growth traits
Treatments
|
Fresh weight g/m2 of weeds
|
Sorghum growth traits
|
Broad leaved weeds
|
Grassy weeds
|
Total weeds
|
Plant height cm
|
Plant weight g/plant
|
Number of leaves/plant
|
Camphor oil
|
109.7
|
258.0
|
367.7
|
190.0
|
956.5
|
13.2
|
Basil oil
|
55.7
|
122.3
|
178.0
|
194.0
|
977.8
|
15.1
|
Stomp extra
|
18.0
|
0.0
|
18.0
|
0.0
|
0.0
|
0.0
|
Adengo extra
|
0.0
|
0.0
|
0.0
|
0.0
|
0.0
|
0.0
|
Cleaner
|
0.0
|
171.0
|
171.3
|
0.0
|
0.0
|
0.0
|
Equip
|
0.0
|
0.0
|
0.0
|
0.0
|
0.0
|
0.0
|
Hand hoeing twice
|
72.0
|
0.0
|
72.0
|
204.6
|
972.2
|
15.3
|
un-weeded
|
806.7
|
385.0
|
1191.7
|
180.8
|
695.7
|
11.9
|
L.S.D. 0.05
|
13.9
|
12.4
|
26.0
|
17.0
|
75.3
|
2.4
|
C.V.
|
9.8
|
9.8
|
9.7
|
5.5
|
5.2
|
11.0
|
The herbicide treatments under study had a phototoxic effect on the sorghum plants, which caused their deaths. These results are due to the chemical weed control in the sorghum crop are limited by the low quantity of herbicides registered for the crop, Pre emergence herbicide as trifluralin, S-metolachlorand clomazon have high toxicity in the sorghum plant, (9), S-metolachlor + mesotrione and S-metolachlor fb prosulfuron reduced sorghum yields by 1121 to 1009 kg ha-1 compared to other treatments, (3).
Essential oils were safe effect on sorghum crop and give improvement growth trait of sorghum crop. Basil oil treatment had the highest values of plant height (cm) plant weight (g) and number of leaves/plant (194 cm, 977.8 and 15.1, respectively), followed by camphor oil treatment (190 cm, 956.5 and 13.2, respectively).
All tested components had significant effect on spike weight and diameter, number of tiller/spike and grain weight g spike-1, where the highest values of the previous parameters were recoded with camphor and basil oil treatment. These results due to the decreased weed competition and increased available of fertilizer nutrients of sorghum plant due to reduced number and weed biomass, (9) and (3).
Table (11) Effect of medicinal oil with adjuvant on yield and yield components of sorghum
Treatments
|
Spike length cm
|
Spike diameters cm
|
Number of tillers/spike
|
Grain weight g / spike
|
Biological yield ton ha-1
|
Grain yield ton ha-1
|
Camphor oil
|
29.7
|
19.2
|
65.6
|
51.0
|
5.8
|
0.27
|
Basil oil
|
32.8
|
21.7
|
70.9
|
69.0
|
8.1
|
0.38
|
Hand hoeing twice
|
41.7
|
22.4
|
74.7
|
65.2
|
7.7
|
0.36
|
un-weeded
|
29.0
|
16.1
|
59.6
|
44.7
|
4.5
|
0.21
|
L.S.D. 0.05
|
7.4
|
3.7
|
4.4
|
1.6
|
1.6
|
0.08
|
C.V.
|
13.9
|
11.6
|
4.0
|
1.7
|
16.7
|
16.7
|
Results in table (11) showed that sorghum yields, biology and grain yield (ton ha-1) were significantly affected by the essential oils in which the highest yield (5.8 and 0.27 ton ha-1) was recorded with the camphor oil treatment, (8.1 and 0.38 ton ha-1) with basil oil and (7.7 and 0.36 ton ha-1) with hand hoeing twice which means that using basil oil and camphor oil for weed control in sorghum caused an increase in grain yield of 28.6% and 81%, respectively, compared with an un-weeded yield (0.21 ton ha-1). These results due to the increased spike weight and diameter, number of tiller/spike and grain weight g spike-1 due to the reduced weed/sorghum competition, (9) and (3).