Journal of Sugar Beet
Year:2009 | Volume:24 | Issue:2|Papers Count:9

Stability analysis and G*E interaction of eight commercial monogerm cultivars of sugar beet were evaluated in three years at 11 major sugar beet producing locations Karaj, Mashhad, Miandoab, Esfahan, Shiraz, Kermanshah, Kerman, Moghan, Hamedan, Khoy, and Brojerd. A randomized complete block design with four replications was used.In each location cultivars Rasoul, Shirin, Univers, Orbis, 7112Hybrid, 436Hybrid and 428Hybrid were recorded. Data collected from each experiment were subjected to simple analysis of variance and after homgenization of error variance, combined analysis for six traits including RY, SY, SC, WSY, NA and Yield were carried out. The stability parameters such as environmental variance, environmental coefficient of variation, linear regression coefficient, mean square deviation from regression, and linear coefficient of determination for each cultivar were determined. The results of the combined analysis showed significant effect of cultivars, Years (Y), Locations (L), Year*Location (Y*L) and Genotype*Year (G*Y). Comparison of means using Duncans new multiple range test showed that cultivars Univers, Orbis and 276Hybrid were superior in many locations compared to other cultivars. Results from stability analysis indicated that Univers and hybrid 276 were the most stable cultivars tested in different environments of Iran.

For evaluation of drought tolerance of sugar beet genotypes by assessment of the drought tolerance indices under mild and severe stresses, furrow irrigated field experiments were carried out at Zarghan Research Station in 2002 and 2004, and at Motahari Research Station (located in Karaj) in 2002, 2003, and 2004. The experimental design was split plot, with a randomized complete block arrangement with four replications. The irrigation treatments as main plots consisted of non-stress, mild stress (75% of the water applied in non-stress), and severe stress (50% of the water applied in non-stress), and sub plots were composed of 10 genotypes. Based on the potential sugar yield (SYp) and stressed sugar yield (SYs), some quantitative criteria of drought tolerance such as mean productivity (MP), tolerance index (TOL), geometric mean productivity (GMP), harmonic mean (HARM), stress susceptibility index (SSI), yield loss ratio (S), and stress tolerance index (STI) were calculated. The positive and significant correlations of SYp and SYs with different water stress indices showed that (a) in Zarghan, under mild and severe stress conditions, STI, MP, GMP and HARM, and (b) in Karaj, under mild stress condition, STI, MP, GMP, and HARM, and under severe stress condition, STI, GMP, and HARM were the best indices that could be used to determine the tolerant genotypes. By considering these indices, and high values SYp and SYs, and also the multivariate biplot display, the most tolerant genotypes were identified as (a) 7221-I-79 and MST261*W-7221-I-79 in Zraghan under mild stress condition, (b) 7221-I-79 in Zraghan under severe stress condition, (c) MSTC2*W-7221-I-79 and 7221-I-79 in Karaj under mild stress condition, and (d) MSTC2*W-7221-I-79 and BP-Mashhad in Karaj under severe stress condition. Distributions of the genotypes in the biplot display indicated the presence of genetic diversity among the genotypes for drought tolerance.

Lepidoteran pests of sugar beet (Beta vulgaris L.) cause a severe yield reduction in the most sugar beet growing areas of the world as well as in Iran. Due to limited genetic resources of resistance to insect pest and polygenic inhertance, improvement of pest resistance in beet by conventional breeding is a difficult task. Biotechnological enhancement by introducing insect resistance genes such as Bt genes provides a complementary/alternative strategy to control insect pest of sugar beet. Two sugar beet diploid genotypes were used for transformation by Agrobacterium tumefaciens strain GV3101 harboring pBI35Scry construct containing synthetic cry1Ab gene under the control of CaMV 35S promoter and nptII gene as selectable marker. Leaf blades including shoot bases were used as explants for tranformation. Putative transformants were screened on medium containing different concentrations of kanamycin. PCR analysis using cry1Ab-specific primers showed the presence of the transgene in a relatively higher than 50% of regenerated kanamycin-resistant plants. Integration of at least one copy of cry1Ab gene into the genome of putative transgenic was confirmed by Dot blot analysis. Western blot analysis using anti-cry1Ab polyclonal antibody revealed the presence of Cry1Ab protein with the expected size of 67 kDa in transgenic sugar beet lines. Based on bioassay results with Spodoptera littoralis, T0 plants were exhibited an enhancement of resistance, ranging 37 to 70% mortality of the pest within 1 week of infestation.

This research was carried out to evaluate the effects of irrigation methods and N fertilizer rates on the quantity and quality of sugar beet in Ekbatan research station during 2001 and 2002. Experiment was performed in split-plot with 3 replications and 15 treatments. Treatments included 3 irrigation systems: sprinkler (solid set), furrow (hydroflum) and drip (tape: 508-20-500) in main plots and 5 N fertilizer rates: 0(control), 60, 120, 180، 240 N kgha-1 in sub plots. The combined analysis of the data showed that differences among N rates were significant (P£0.01) for root, sugar and white sugar yield. The effects of irrigation systems on root (P£0.01) and white sugar yield (P£0.05) were significant: N fertilizer rates significantly affected IWUE (P£0.01), but interaction between irrigation systems and N fertilizer rates were not significant on IWUE. IWUE was decreased in drip (tape), sprinkler and furrow respectively. Water consumption decreased averagely 45.8% and 36.8% in drip irrigation as compare to furrow and sprinkler irrigation respectively. Water consumption in sprinkler irrigation was 22.2% less than that in furrow irrigation.

In order to evaluate the efficiency of empirical competition models for simulation of sugar beet (Beta vulgaris L.) yield at interference with redroot pigweed (Amaranthus retroflexus L.), a factorial experiment based on randomized complete block design with three replications was carried out. Factors were weed densities (d1=1, d2= 4, d3= 8, d4=12 and d5=16 plants m-1 of row) and relative time of weed emergence (i1=emerged with sugar beet; i2=10, i3= 20 and i4=30 days after sugar beet emergence) included with a weed free control plot. Yield data were analyzed by four nonlinear regression models. Results revealed that sugar beet LAI reduced, when weed density increased and redroot pigweed (RP) emerged earlier, and the role of weed density was more effective than time of emergence for this characteristic. In treatments with low sugar beet LAI, RP LAI was more. Full-season interference of 16 RP m-1 of row decreased sugar beet root yield from 75 tha-1 in control to 58 tha-1. Increasing of each weed plant, reduced sugar yield 1.3 and 0.3 tha-1 in density intervals of 8-12 and 12-16 plants m-1, respectively. Cousens model had the best sugar beet yield simulation based on RP density and relative emergence time because of high R-square, low standard error and low mean percentage error and root mean square error values. In this model, mean percentage error increased from 1.4% to 9.36% based on root yield and sugar yield, respectively.

To determinine the timeliness cost of machine operation, farm-level data were collected from random sample of 227 sugar beet farms located in the three major districts of Fars province of Iran: Eghlid, Marvdasht and Fasa in 2006. The results showed that timeliness cost of tillage practices (plough and land leveling), applying fertilizers before planting and timeliness in seed planting per everyday lag were 12237, 3147, 881 and 2622 Rials/ha respectively. Timeliness cost of machine operation in stages of applying chemical fertilizers after planting, applying chemical pesticides and cultivation per everyday lag were 881, 1101 and 3671 Rials/ha respectively. The results of production elasticity indicated a significant negative relationship between timeliness of tillage practices, machine operations (such as plough, land leveling, planting and …) and yield of sugar beet.

The objective of this study was to develop a cost minimizing pattern for cube sugar and sugar transportation from production centers to refinement and storage centers and finally to distribution and consumption  centers in  Fars province. Producing centers are Marvdasht (27.3%), Eghlid (27.9%), Fasa (11.3%), Kavar (7.3%) and Mamasani (20.2%). Some of the province’s cube sugar and sugar is provided by import. The refinement and storage centers receiving the production of the mentioned producing centers are Marvdasht, Yasuj, Boosher, Eghlid, Abade, Lar, Abarghoo, Fasa, Tehran, Isfahan, Mamasani, Kazeroon, Istahban and Sepidan. The consumption centers also include all of Fars province townships. The transportation cost of the current transporting network amount to 56.55 billion Rials reducing by 23% in optimal solution. Of the figure, transportation network between producing and refinement and storage centers accounts for 71.1% and 28.9% of the total cost rise from transportation network between refinement and storage and distribution and consumption centers. The main changes in network between producing and refinement and storage centers relate to transporting paths of Marvdasht, Eqlid and Mamasani. In optimal pattern production of Marvdasht is allocated to Yasuj, Boosher and Abarghoo in addition to Marvdasht and Shiraz. In optimal pattern, Eqlid’s production instead of Shiraz’s refinement and storage centers is transported to Tehran and Isfahan ones. A part of Mamasani’s production being transported to Tehran and Isfahan in current network is allocated to Yasuj and Boosher. In the transportation network between refinement and storage and distribution and consumption centers the main difference of current and optimal solutions relates to refinement and storage of Shiraz, Eqlid and Abade.

In this paper the use of farm machinery in sugar beet farms in Fars province was studied. The necessary data, with two-stage cluster sampling method in Fasa, Eghlid and Darab cities on 2004-2005 were collected. From 203 farmers selected for the study. 113 of them were in high level mechanization group and 90 of them were in low level mechanization group. In this study, the effect of farm machinery in production, comparison of inputs amount usage and comparison of productivity and efficiency in 2 mentioned groups were considered. The results of study showed significant differences in yield average, machinery operation cost and irrigation. The study of mechanization usage showed that machinery activity cost had more influence on farm production. Variable coefficient of machinery activity cost factor in this model was 0.311. Based on the results, technical efficiency of low level mechanization groups wasn’t non possibility calculate, the maximum and minimum technical efficiency of high level mechanization groups were 99% and 11% respectively and its average was 58.4%. These findings show that no change is technology or inputs are needed to decrease difference.