مجله چغندر قند
سال بیست و دوم شماره 2 (پاییز و زمستان 1385)

In order to evaluate salinity tolerance in 20 sugar bee genotypes, an experiment was conducted in two fields with salinity (EC= 12 ds/m, pH= 7.6) and non-salinity stress, in the form of RCBD at Miandoab Agricultural Research Station. Different morphological and physiological traits such as root yield, sugar percentage, white sugar percentage, Molasses, N, Na, K, syrup purity and green cover percentage were recorded in salinity and non-salinity conditions. Germination percentage, seed vigor and establishment percentage were measured separately in a greenhouse experiment in karaj, using a factorial experiment based on CRD with two factors A (20 genotypes and B(two levels of salinity of 16 and distilled water). Arcsin transformation was used to analyze the data obtained from the greenhouse experiment. Results of the experiments showed a high variability among the genotypes and origins. Salinity stress caused 77% and 36% decrease in root yield and white sugar yield, respectively. The Na/K ratio was identified as a suitable criterion for selection of the tolerant salinity genotypes in field condition. The index of tolerance to stress was calculated for all of the genotypes and showed that the genotypes C3.3 (Tetraploid Multigerm) with index of 0.3 and 25.48 ton/ha yield had a good tolerance under field salinity conditions.In the greenhouse condition, genotypes C3.3 (Tetraploid Multigerm), 19669-p5 had a good tolerance under farm salinity conditions.

To determine the most important traits affecting root yield and sugar content in monogerm germplasm of sugar beet, 75 monogerm F1 hybrids were evaluated in three separate experments conducted in randomized complete block desing (RCB) with four replications at Abdo–al–Rasoul Research Farm, Karaj in 2004. Root yield, root length, root diameter, crown height, crown diameter, sugar content, α–amino–nitrogen, sodium, potassium, K/Na ratio, K/SC ratio, N/SC ratio, alkality coefficient, white sugar yield, molasses, white sugar content, sugar yield, root uniformity, growth score and purity were measured. Mean of treatments were used for statistical analysis. Factor analysis by principal component methods, revealed that all of the traits could interpret in three factors, white sugar content, root yield and morphological charactors of root. Stepwise regression analysis for root yield as dependent variable ad other traits as independent variables, showed the importance of sugar yield, sugar content, white sugar yield, alkality coefficient, root diameter and crown lenghth. The relationships among root yield with sugar yield, white sugar content and root diameter were positive. Also, white sugar content, K/Na ratio and purity contributed largely to the sugar content. Canonical correlation revealed that increasing of root length and diameter and decreasing of crown diameter accompanied by decreasing root impurities.

To study the effect of variable irrigation in spring on water use efficiency, quantity and quality of root and sugar yield of two sugar beet cultivars Shirin and Rasolan, an experiment was conducted at Safiabad Agriculctura Research Center during 2003-04 and 2004-05 cropping seasons. The experiment was designed in a split plot with four replications in which five water supply treatments 25, 50, 75,100 and 125 percent of the plant water requirment (PWR) as drip irrigation were in main plots and two sugar beet cultivars in subplots. There was a significant difference between years for most of the sugar beet yield parameters, whereas differences among water supply treatments were significant only for root yield, α-N, alkalinity, and irrigation water use efficiency (IWUE) of root and sugar yield. Increasing of water volume increased root yield and alkalinity and decreased IWUE for sugar and root yield. The 100 and 25% PWR treatments had the highest (84t/ha) and the lowest (76t/ha) root yield, respectively. The 25% PWR treatment had the highest IWUE for root and sugar yield which were 18.7 and 2.6 kg/m3, respectively. There was no significant difference between cultivars for any of yield parameters. Increment of water supply increased leaf area, leaf number and fresh dead leaves (leaf+petiole) and reduced root/shoot ratio, and dry matter of leaf and root. Based on the results of this experiment, the 25% PWR as drip irrigation in spring, can be recommended for autumn sugar beet in Dezful region.

Sustainable agriculture for producing food is not possible without optimal use of water resources. Because of the limitation of water resources, deficit irrigation would be essential to increase water productivity. In order to evaluate the effects of deficit irrigation on quality and quantity of sugar beet, an experiment was carried out in a farm in Miandoab Agricultural Research Station for 2 years(1999-2000). The experiment was conducted in a split–plot design on the basis of randomized complete blocks with three levels of irrigation (100%, 75% and 50%) and three irrigation intervals (7,10,14 days) in four replications. The analysis of two years results indicated that there was a significant difference at 1% level among deficit irrigation and root yield and sugar yield. Deficit irrigation decreased root yield and sugar yield, but because of the positive effect of deficit irrigation on sugar beet quality, the rate of root yield decrease was more than the rate of sugar yield. D7S100 treatment (irrigation interval 7 days and full irrigation), providing 100% of water need of plant, produced the highest root yield (67.71 t/ha) but in D14550 treatment root yield decreased by 48.7 percent. The effects of deficit irrigation was more on longer irrigation intervals. The results also indicated that the 50 percent levels of irrigation resulted in less root yield and sugar yield which may not be accepted by farmers, Therefore it cannot be recommended. Considering water productivity, and avoiding S50 treatment, treatment D10S75 is recommended for the region. With 28.9% reduction in water use, there was only 23.5% and 16.6% reduction in root yield and sugar yield, respectively.

The use of organic fertilizer brings about an increase in the organic matter of soil and the microbiological activities. Generally as the soil in many parts of Iran is poor, the use of manure is suggested for improvement of soil structure and physical and chemical properties to increase yield and to reach a sustainable agriculture. This investigation was conducted during 2001-2004 in Karaj at the experimental station to study the effects of different amounts of manure on quality and quantity of sugar beet. The experiment was carried out in a complete block design with three replications in permanent plots for no-manure, 30ton manure/ha and 60ton manure/ha treatments. A cereal-sugar beet rotation for two cycles was followed in the experimental field. Manuring was done in autumn before wheat planting in order to avoid any detrimental effect on beet quality. Beet quantitative and qualitative traits along with physical and chemical properties of the soil were recorded. The results showed that the use of manure increased the grain weight (of wheat) and total yield significantly. Wheat crop yield of 4.17t/ha in the no-manure increased to 5.41t/ha in 30t manure/ha treatment. The white sugar yield increased significantly from 5.78 to 6.78 t/ha using manure, although the sugar content suffered a decrease. The 60t/ha treatment increased the organic carbon of the soil from 0.81 to 0.94 percent. Furthermore, manuring improved the soil physical condition with apparent specific weight of soil at 0-20 cm depth which decreased from 1.46 g/cm3 in no-manure treatment to 1.38 g/cm3 in 30ton manure/ha, while the water capacity of soil improved significantly by the increase of soil organic matter. Moreover, crop nutrition was improved by manuring of the soil and diminished the need for chemical fertilization. Manuring with 30ton manure/ha before wheat cultivation is justified

To determinate the most proper N.P.K. fertilizer level for increasing the quality and quantity of polygerm seeds of sugar beet, an experiment was conducted in randomized complete block design with three replications in 1998-2000 at Research Farm of Faculty of Agriculture, Azad University of Ardabil (Hassan Barog). Fertilizer treatments were: N30P60K60, N90P90K90, N0P0K0, N90P150K150, N90P120K120, N90P90K120 and N60P60K60. The results showed that generally in all treatments, plant height and number of main stems significantly differed at 5 percent and seed yield and germination percentage differed at 1 percent level of probability. The highest seed yield was obtained from N90P90K90 and N90P90K120 treatments. In addition, the treatment N90P90K120 had the highest germination percentage.

In ordet to investigate economic efficiency of five cultural systems in sugar beet crop, including high input, medium input low input, high and medium inputs without 3 times irrigation after emergence, an experiment was conducted over two years (2002-2003) in Agricultural and Natural Resources Research Center of Khorasan. These systems were analysed by marginal analysis and linear programming methods. Results showed significant difference among treatments for root yield, sugar and white sugar yield, sugar and white sugar content, sodium, potassium, α - amino azote and molass sugar.The maximum yield (52.11 ton/ha), was obtained from high input treatment and the minimum yield 35.89 (ton/ha) was obtained for medium input traetment without 3 times irrigation. Economic analysis showed that, low input treatment had the highest water efficiency followed by medium input treatment which had the highest economic rate of return. Beside, change in price of water, led to change the optimum treatment.

In order to study the effective factors in sugar beet production, evaluation of technical, allocative and economical efficiency of sugar beet producers in Bardsir city, 150 sugar beet producers were questioned by classified method. Data were collected through questionnaire forms filled by producers in 2004-05. The stochastic frontier production and cost function method were used to analyze the data. The results showed that, average rate of technical, allocative and economic efficiencies in Bardsir were 69%, 81% and 56%, respectively. The effects of the number of field, education, and time of the last irrigation were evident on sugar beet producers technical efficiency.