The authors have declared that no competing interests exist.
This investigation was carried out at the Demonstration Farm of the College of Agriculture- University of Bahri during 2018/2019 winter season to evaluate growth (morphological) and growth analysis (physiological) components in some sugar beet (
Sugar beet (
Sudan has meager information about beet production although scientific research on the crop is going back to 1930s when the first trials were carried out at Gezira Research Farm
To evaluate growth and some growth analysis components in six sugar beet genotypes under AlKadro agro-climatic conditions through the growing season.
To evaluate growth and some growth analysis components in some sugar beet genotypes under low nitrogen fertilizer levels at different terms through the growing season.
A field experiment was carried out during 2018/2019 at Demonstration Farm of University of Bahri at Al Kadro on latitude 15◦ 45′N, longitude 32◦ 39′E and altitude of 398 m above sea level, in Khartoum State, Sudan. In a semi-arid zone with maximum and mean temperature of 45◦C and 30
The method was suggested by
Where, W1and W2 are whole plant dry weight at time t1– t2 respectively, ρ is the ground area on which W1 and W2 are recorded. CGR of a species are usually closely related to interception of solar radiation.
Relative Growth Rate (RGR). The term was coined by
The term, NAR was used by
Statistical analysis of experimental data was carried out by using the SPSS software package and the means were separated by Duncan’s multiple range test with at least P≤0.05.
The data analysis of this study is presented in the
SV | Leaf number per plant | Leaf area index (LAI) | ||||||||
Terms of sampling | Terms of sampling | |||||||||
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G0 | 16.74a | 30.09b | 47.04a | 44.8a | 31.30 | 1.420a | 4.28a | 5.638a | 3.779ab | 1.638ab |
G1 | 14.33b | 22.39c | 27.10c | 32.13a | 26.77a | 1.329a | 3.258a | 4.284bc | 2.603c | 1.380a |
G2 | 17.03a | 27.29b | 26.91c | 45.80a | 35.64a | 1.698a | 4.291a | 4.914b | 4.747a | 1.989a |
G3 | 15.92b | 30.92b | 35.12b | 39.06a | 34.10a | 1.635a | 5.007a | 5.645a | 3.722ab | 1.808a |
G4 | 17.43a | 35.73a | 38.47b | 45.19a | 33.75a | 1.493a | 4.377a | 4.915b | 3.748ab | 1.698a |
G5 | 16.61a | 26.23b | 28.55c | 41.08a | 31.81a | 1.513a | 3.585a | 3.725c | 3.519bc | 1.698a |
Sy‾ | 0.80 | 1.80 | 2.41 | 3.58 | 2.47 | .118 | .419 | .416 | .432 | .161 |
F test | * | * | * | Ns | Ns | Ns | Ns | * | * | Ns |
N0 | 17.14a | 28.84a | 33.45a | 43.31a | 33.42a | 1.634a | 3.983a | 4.711a | 3.893a | 1.760a |
N1 | 15.76a | 29.04a | 34.80a | 41.53a | 31.63a | 1.490a | 4.140a | 4.761a | 3.698a | 1.675a |
N2 | 16.13a | 28.44a | 33.34a | 39.19a | 31.64a | 1.420a | 4.245a | 4.599a | 3.467a | 1.793a |
Sy‾ | 4.81 | 1.27 | 1.71 | 2.53 | 1.75 | .0.083 | .296 | .294 | .305 | .114 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS` | NS |
GxN Sy‾ | 1.81 | 3.11 | 6.19 | 6.19 | 4.28 | .204 | .726 | .721 | .747 | .279 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
NB. 1,2,3,4,&5 designate for 4 ,7,10, 13 & 16 weeks after sowing date (WAS).
Considering
Means of leaf number per plant as affected by genotype, low nitrogen fertilizer rates and interaction between genotype and nitrogen fertilizer (G x N) are presented in
The mean values of leaf area index (LAI) as affected by genotype, nitrogen and their interaction are presented in
S V | Fresh weight of leaves per plant (g) | Dry weight of leaves per plant (g) | ||||||||
Sampling Terms | Sampling Terms | |||||||||
Factors | 1 | 2 | 3 | 4 | 5 | 1 | 2 | 3 | 4 | 5 |
G0 | 199.01a | 663.49b | 528.27a | 363.05a | 178.62a | 23.55a | 57.84a | 69.49a | 70.27a | 31.77a |
G1 | 176.76a | 663.49b | 559.42a | 334.39a | 170.85a | 22.19a | 58.46a | 72.13a | 62.18a | 31.87a |
G2 | 253.28a | 764.27a | 464.37a | 367.68a | 192.41a | 27.08a | 57.68a | 67.27a | 66.77a | 31.74a |
G3 | 193.35a | 648.28b | 650.85a | 495.18a | 229.36a | 23.66a | 61.33a | 69.93a | 60.43a | 35.01a |
G4 | 215.45a | 568.64b | 514.70a | 321.68a | 209.60a | 24.92a | 56.13a | 69.30a | 57.33a | 33.09a |
G5 | 192.47a | 732.92a | 525.56a | 338.33a | 190.13a | 21.33a | 60.61a | 63.27a | 51.63a | 34.63a |
Sy‾ | 18.04 | 41.92 | 63.21a | 76.27 | 19..47 | 1.67 | 3.44 | 3.86 | 4.27 | 2.19 |
F test | NS | * | NS | NS | NS | NS | NS | NS | NS | NS |
N0 | 210.94a | 666.48a | 504.03a | 432.40a | 200.68a | 24.82a | 57.28a | 62.73a | 59.99a | .33.10a |
N1 | 208.94a | 674.17a | 510.73a | 347.41a | 191.92a | 23.74a | 58.64a | 71.68a | 63.55a | 32.85a |
N2 | 195.50a | 666.39a | 606.82a | 330.34a | 192.88a | 22.80a | 60.11a | 70.80a | 60.76a | 33.10a |
Sy‾ | 12.76 | 29.68 | 44.7 | 53.93 | 13.76 | 1.18 | 2.43 | 2.73 | 3.02 | 1.55 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
Gx N Sy‾ | 31.25 | 72.71 | 109.49 | 132.11 | 33.72 | 2.9 | 5.95 | 6.68 | 7.39 | 3.8 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
NB. see the foot note of
Means of fresh and dry weight of leaves per plant as affected by genotype, low nitrogen fertilizer levels and their interaction are shown in
Mean values of root dimensions (length and diameter) obtained from the six sugar beet genotypes grown under low N fertilizer levels are shown in
Means of fresh and dry weight of root per plant as affected by genotype, nitrogen fertilizer rate and interaction between genotype and nitrogen fertilizer (GXN) are presented in
Growth analysis as the first step in the analysis of primary production being a link between merely recoding plant productions and analyzing it by means of physiological methods. However, biomass increments in plant or root stands expressed in ground area basis (Crop growth rate = CGR), The rate of increase in biomass per unit of biomass present (Rate growth rate=RGR) and the rate of increase of dry weight per unit time per unit area of leaf surface (Net assimilation rate= NGR) are presented in
Concerning relative growth rate (RGR) data in
Moreover, with regard to Net assimilation rate (NAR), data in
In the light of the present study, it could be assumed that tested genotypes may have the same requirements and reactions to the local environmental effects genetically. Therefore, these physiological components indicated that the evaluated genotypes did not differ in the proportion of photosynthetates partitioned into dry weight. Moreover, the non – significant effect of the nitrogen fertilizer level on all the studied growth and some growth components indicates that the low nitrogen fertilizer levels applied may not enhanced the uptake of nitrogen increased (N1 & N2) and the slight unsubstantial variations among the levels could be due to utilization of accumulated nitrogen. This view is in agreement with who reported that the response of sugar beet depended on the N available in the soil. Nevertheless, no crossover interaction occurred for the fore mentioned parameters, there to be no specific suitability of the tested genotypes to environmental stress condition. The interaction between genotype and N fertilizer level effect on all the evaluated parameters was absent or insignificant. These findings were in line with those reported by
In this study of six sugar beet genotypes; the variation in root and plant growth rate, relative growth rate (RGR) and net assimilation rate (NAR) revealed no substantial differences among the genotypes or tested Nitrogen levels. This is probably arises because the beet is a vegetative storage organ and has no clear growth stages that particularly susceptible to unfavorable environmental conditions. Nevertheless, no significant interaction between genotype and N fertilizer level indicates a similar response of genotypes; not depending on N level. These findings were in line with those reported by
It has been noticed that sugar beet has ability of compensating its morphological growth components through the season. This could be fortified by the significant effects in some stages and insignificant in others among the studied genotypes.
SOV | Fresh Weight of foliage (g/plant) | Dry Weight of foliage (g/plant) | ||||||||
Sampling terms | Sampling terms | |||||||||
Factors | 1 | 2 | 3 | 4 | 5 | 1 | 2 | 3 | 4 | 5 |
G0 | 219.05b | 743.58a | 608.93a | 478.68a | 324.48a | 24.73a | 65.75a | 90.23a | 94.10a | 63.41a |
G1 | 186.93bc | 686.8a7 | 632.20a | 435.84a | 339.93a | 23.96a | 6a5.63a | 90.32a | 85.83a | 73.33aa |
G2 | 272.06ba | 787.96a | 531.77a | 482.65a | 331.49a | 29.52a | 6a4.19 | 81.96a | 91.09a | 63.12a |
G3 | 205.51b | 706.74a | 653.13a | 468.61a | 423.79a | 25.34a | 64a.03 | 91.33a | 89.34a | 73.48a |
G4 | 230.72a | 622.58a | 597.76a | 493.18a | 370.57a | 27.68a | 65.5a3 | 83.64a | 80.62a | 69.43a |
G5 | 204.60b | 765.78a | 606.04a | 418.55a | 302.43a | 23.32a | 69.52a | 76.84a | 69.00b | 44.34b |
Sy‾ | 19.02 | 47.39 | 40.07 | 51.76 | 31.57 | 1.96 | 5.08 | 6.14 | 6.29 | 7.29 |
F test | * | NS | NS | NS | NS | NS | NS | NS | * | * |
N0 | 228.36a | 729.75a | 575.44a | 446.19a | 348.31a | 26.45a | 63.51a | 82.69a | 83.40a | 66.34a |
N1 | 222.73a | 708.80a | 611.28a | 496.63a | 356.20a | 26.31a | 65.04a | 88.61a | 8a8.38a | 62.74a |
N2 | 208.35a | 718.20a | 628.20a | 445.94a | 341.84a | 24.51a | 68.78a | 85.62a | 83.21 | 64.45a |
Sy‾ | 13.45 | 33.51 | 28.33 | 36.6 | 22.33 | 1.39 | 3.59 | 4..34 | 4.45 | 5.16 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
Gx N Sy‾ | 32.94 | 82.09 | 69.4 | 89.65 | 54.68 | 3.4 | 8.79 | 10.63 | 10.89 | 12.63 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
NB. see the foot note of
Source of Variation | Root Length (cm) | Root Diameter (cm) | ||||||||
Sampling Terms | Sampling Terms | |||||||||
Factors | 1 | 2 | 3 | 4 | 5 | 1 | 2 | 3 | 4 | 5a |
G0 | 19.05b | 26.14a | 26.83 | 25.54a | 27.41a | 4.01a | 8.12b | 9.05a | 11.92a | 11.18a |
G1 | 21.75a | 26.21a | 27.28 | 26.82a | 27.44a | 4.03a | 7.93bc | 9.88a | 10.58ab | 10.86a |
G2 | 20.55ab | 27.38a | 27.25 | 28.13a | 26.86a | 4.07a | 9.48a | 10.82a | 11.57a | 11.54a |
G3 | 21.73a | 28.94a | 29.85 | 29.12aa | 28.75a | 4.38a | 8.20b | 9.66a | 10.40ab | 11.02a |
G4 | 20.70ab | 28.16a | 27.66 | 26.79a | 27.43a | 4.40a | 8.25b | 9.26a | 10.09b | 10.36a |
G5 | 19.93ab | 27.13a | 26.99 | 25.93a | 29.62a | 4.06a | 8.40b | 9.83a | 10.83ab | 10.83a |
Sy‾ | 0.89 | 0.86 | 1.04 | 1.37 | 1.41 | 1.91 | 0.34 | 0.26 | 0.49 | 0.30 |
F test | * | NS | NS | NS | NS | NS | * | NS | * | NS |
N0 | 21.33a | 27.54a | 27.43 | 26.97a | 27.55a | 4.42a | 8.64a | 9.54a | 10.68a | 11.17a |
N1 | 20.25a | 27.01a | 26.93 | 27.49a | 27.21a | 4.27a | 8.28a | 9.61a | 10.88a | 10.96a |
N2 | 20.28a | 27.43a | 28.58 | 26.71a | 28.49a | 4.10a | 8.27a | 9.70a | 10.86a | 10.77a |
Sy‾ | 0.63 | 0.81 | 0.73 | 0.97 | 1.00 | 1.35 | 0.24 | 0.18 | 0.35 | 0.21 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
Gx N Sy‾ | 1.54 | 1.49 | 1.79 | 2.73 | 1.99 | 0.33 | 0.59 | 0.45 | 0.85 | 0.51 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
NB. see the foot note of
S V | Fresh weight of root (g/plant) | Dry weight of root (g/plant) | ||||||||
Sampling Terms | Sampling Terms | |||||||||
Factors | 1 | 2 | 3 | 4 | 5 | 1 | 2 | 3 | 4 | 5 |
G0 | 86.59b | 487.43a | 586.78b | 1326.57a | 1189.39a | 17.64ab | 128.43a | 189.06c | 413.00a | 268.22a |
G1 | 72.66b | 405.36a | 741.00b | 999.21a | 1003.46a | 15.29bc | 108.84a | 283.73ab | 396.18a | 240.79a |
G2 | 105.24a | 538.58a | 734.58b | 1185.21a | 1092.93a | 19.09ab | 167.98a | 252.14b | 420.24a | 274.43a |
G3 | 106.67a | 532.45a | 913.81a | 1183.17a | 1247.88a | 18.34ab | 175.60a | 326.43a | 432.18a | 263.03a |
G4 | 108.88a | 503.89a | 726.90b | 1070.14a | 1123.32a | 22.08a | 148.74a | 251.52b | 355.44a | 240.40a |
G5 | 79.28b | 509.68a | 702.93b | 844.84a | 943.19a | 12.54c | 146.98a | 222.81b | 286.46a | 221.11a |
Sy‾ | 9.19 | 54.55 | 63.58 | 156.65 | 102.83 | 1.63 | 19.02 | 23.9 | 37.81 | 20.2 |
F test | * | NS | * | NS | NS | ** | NS | ** | NS | NS |
N0 | 102.78a | 527.77a | 724.62a | 1070.26a | 1127.59a | 18.79a | 158.00a | 247.18a | 384.84a | 281.78a |
N1 | 90.22a | 494.82a | 735.01a | 1225.32a | 1146.93a | 17.32a | 140.62a | 257.94a | 388.65a | 258.70a |
N2 | 85.15a | 466.10a | 743.37a | 1008.98a | 1020.56a | 18.38a | 139.67a | 257.72a | 378.27a | 233.51a |
Sy‾ | 6.5 | 38.63 | 44.95 | 110.77 | 72.72 | 1.15 | 13.45 | 16.9 | 26.74 | 14.28 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
Gx N Sy‾ | 15.91 | 94.49 | 110.11 | 271.33 | 178.77 | 2.82 | 32.94 | 41.4 | 65.99 | 34.99 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
NB. see the foot note of
S V | Growth Analysis Parameters | |||||||||
Period between sampling terms | ||||||||||
RCGR ( g cm-2 day-1) | RGR (g g-1day-1) | NAR (g cm -2 day-1) | PCGR (g cm-2 day-1) | |||||||
Factors | 02-Jan | 03-Feb | 04-Mar | 02-Jan | 03-Feb | 04-Mar | 2 – 1 | 02-Jan | 03-Feb | 04-Mar |
G0 | 0.004 | 0.003 | 0.007 | 0.04 | 0.019 | 0.013 | 0.007 | 7.169 | 4.222 | 7.741 |
G1 | 0.003 | 0.007 | 0.005 | 0.04 | 0.018 | 0.008 | 0.008 | 6.427 | 9.15 | 5.518 |
G2 | 0.005 | 0.004 | 0.005 | 0.045 | 0.015 | 0.011 | 0.01 | 6.729 | 5.263 | 7.857 |
G3 | 0.005 | 0.006 | 0.004 | 0.016 | 0.013 | 0.006 | 0.009 | 9.571 | 8.899 | 5.928 |
G4 | 0.004 | 0.004 | 0.005 | 0.039 | 0.014 | 0.009 | 0.008 | 7.873 | 5.757 | 5.742 |
G5 | 0.005 | 0.003 | 0.004 | 0.045 | 0.012 | 0.01 | 0.008 | 8.481 | 4.238 | 5.589 |
Sy | 0.001 | 0.001 | 0.001 | 0.003 | 0.003 | 0.002 | 0.001 | 1.06 | 1.833 | 2.277 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
N0 | 0.005 | 0.004 | 0.006 | 0.044 | 0.012 | 0.01 | 0.009 | 8.374 | 5.18 | 6.697 |
N! | 0.004 | 0.005 | 0.005 | 0.041 | 0.018 | 0.008 | 0.007 | 7.673 | 4.076 | 6.453 |
N2 | ..005 | 0.004 | 0.005 | 0.043 | 0.016 | 0.01 | 008 | 4.978 | 6.264 | 5.572 |
Sy‾ | 0 | 0.001 | 0.001 | 0.002 | 0.002 | 0.001 | 0.001 | 0.75 | 1.296 | 1.61 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
GxNSy‾ | .006. | 0.005 | 0.003 | .006. | 0.005 | 0.003 | 0.002 | 1.838 | 3.167 | 3.943 |
F test | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
NB. see the foot note of
To this end, it could be concluded that all the studied genotypes could be cultivated successfully under Al Kadro, Khartoum North climatic and soil conditions. The tested low nitrogen fertilizer levels coupled with very low available nitrogen and organic carbon in the soil; ranged between 0.00-0.003 % and 0.002-0.01%, respectively, not enhanced nitrogen uptake and no substantial interaction (GxN), also, the growth analysis components reflected non-significant effect among the studied genotypes, nitrogen levels and their interaction. Therefore, further research is needed to fix outstanding genotype and optimum rate of nitrogen for benefit of the farmer, environment and developing local sugar and fodder industry in the area.
The authors wish to thank Ministry of Higher Education and Scientific Research for funding this work, and extend their gratitude to Prof. Hydr and Dr Basim of ARC (of the Executive Committee for Sugar Beet Introduction). Sincerely thanks to Dr. SalahEldin A Mukhtar and his aides at the Sugarcane Research Center-Guneid, Sudanese Sugar Company for their technical and raw material analysis support, Also, thanks to College of Agriculture - University of Bahri, and Animal Production Research Center- Ministry of animal Wealth for accommodating the project in their premises.