مجله چغندر قند
سال بیست و نهم شماره 2 (پاییز و زمستان 1392)

Rhizomania is the most important disease of sugar beet in Iran and some other parts of the world, and plays an essential role in decreasing sugar yield in fields. The best approach to control this disease is to use resistant varieties. Tagging the resistance genes in breeding programs, by molecular markers is necessary. In this study, some breeding populations and commercial varieties of sugar beet originated from Rz1 resistance source were used for validation and repeatability of 6 repulsion molecular markers. Accordingly, ELISA data related to greenhouse evaluation of rhizomania resistance were used in some breeding populations. For molecular analysis, DNA was extracted from leaf samples and RAPD-PCR was performed by using the primers related to the markers of interest. The RAPD-PCR products were separated by gel electrophoresis, After electrophoresis, was stained with ethidium bromide and was observed using gel documentation device and finally was scored for the presence or absence of marker bands. In next step, conformation of the markers with ELISA data in single plants were measured in breeding populations and the precent presence of the markers in commercial varieties was determined. Comparison between ELISA and molecular analysis results showed that repulsion markers (the markers linked to the susceptibility allele) PN3 and PN7-2 had acceptable agreement with ELISA (92% and 98% respectively), susceptible varieties (87% and 90% respectively), and resistant varieties (75% and 97% respectively). Also, the results of the gene dose effect showed that the average OD value of ELISA of the dominant homozygote plants (Rz1Rz1) was significantly lower than the heterozygote plant (Rz1rz1) in the repulsion markers.

There is a long period between harvested beets and their transfer to the sugar factory. Sugar beet crop is damaged and injured during harvest and transport which provides a suitable place for various saccharoliytic microorganisms growth in terms of temperature, moisture, pH and glucose concentration. In this study, samples were randomly selected from the roots stored in spring 2010 and also the processed syrup in one of the sugar factories in Isfahan, to isolate and identify microorganisms. After washing and disinfecting the root’s surface, infected pieces were taken from different parts of tissue. After preparation of dilution series, isolation and identification of microorganisms were carried out using standard microbiological methods. In the next stage, the impact of the ethanolic extract of the honey bee prepolis as an antimicrobial agent was studied under the controlled environment on the isolated bacteria and fungi. And, its effect was compared with two disinfecting materials, i.e. sodium hypochlorite and calcium hypochlorite. Different kinds of gram-positive bacilli and cocci, including genus Bacillus, Leuconostoc, Staphylococcus and Streptococcus from bacteria, and several types of fungi constitute Paecilomyces, Chrysosporium, Pencillium, Fusarium and Pythiumwere isolated, purified and identified. Pathogenic bacteria such as Staphylococcus aureus and Staphylococcus saprophyticus were detected among the isolated bacteria. Bacterial counting in heated syrup showed the presence of bacterial spores and the re- growth of bacteria as 53 colony forming units per ml. after emergence. The bacterial population remained in heated syrup was belonged to the Bacillus species. These bacteria are called as ‘ human opportunistic pathogens’ and some of them are allergens. Therefore, it is important to control their population instored sugar beet which can improve the quality of the crop and health parameters. Ethanol extract from bee Propolis had significant effect on isolated microorganisms, so that the minimum lethal concentration of Propolis was 6 times less than sodium hypochlorite and 12 times less than calcium hypochlorite.

In order to assess the heritability of short vegetation period (early maturity) of sugar beet hybrids, an experiment was carried out in randomized complete block (RCB) design with 4 replications in Abdolrasoul Motahari Agricaltural Research Station of Sugar Beet Seed Institute, Karaj, Iran in 2009. In this research, the heredity of the traits in testcrosses derived from crosses of 18 half sib families with a male sterile line accompanied by a short vegetation period check variety was evaluated under late sowing condition (about late June). ANOVA results showed that there were no significant differences among the testcrosses for most of the traits- Means comparison showed that the hybrids 3, 9, and 16 had slight difference with the check variety for most traits. The testcross 3 was considered suitable for short growth period which was comparable with the commercial check variety. For morphological traits (such as leaf number and crown height) and some impurity traits (such as sodium and extraction coefficient of sugar), narrow- sense heritability was high. Therefore, there is still possibility to improve the above- mentioned traits with respect to the short vegetation period in the half- sib families. For root yield, sugar yield, and white sugar yield, the heritability was about zero. Root yield had significant positive correlations with sugar yield, white sugar yield, root diameter, and crown height and significant negative correlation with sugar content.

Due to the scarcity of water resources, the need for sustainable development of drip irrigation tape is essential in Iran. A number of drip irrigation tape systems used in sugar beet fields of Isfahan and Chahar mahal va Bakhtiari provinces were evaluated and were compared with furrow irrigation methods in two consecutive years. The actual water use efficiency (WUEsy, WUEwsy) in lower quarter, water use efficiency potential, uniformity of water droppers in lower quarter, uniformity of water movement from water droppers, Christiansen’s uniformity coefficient, uniformity water distribution as well as quantity and quality of sugar beet were investigated in this study. The actual water use efficiency varied in the range of 49 to 74.5%. The average uniformity distribution coefficient of water droppers was 73.8% and Christiansen’s uniformity coefficient was 82%. The drip irrigation tape system had significant difference with furrow irrigation method in terms of water use efficiency in sugar yield and recoverable white sugar (P£0.05). These values were 0.91, 0.78 and 0.65 and 0.53 for drip irrigation tape and furrow irrigation systems, respectively. Both irrigation systems had no significant difference in terms of root yield and sugar beet crop quality parameters. The average water use efficiency in sugar yield and recoverable white sugar for drip irrigation tape were 0.91and 0.65 Kg. m-3 and for furrow irrigation system were 0.78 and 0.53 Kg. m-3, respectively.

Water and soil salinity in some regions of Isfahan, East Azerbaijan, and West Azerbaijan provinces and also other parts of the Iran are the main hindrance for crop planting. Seeds of the tolerant crops to salinity such as cotton and sugar beet may have optimal germination and give acceptable performance if they become far from salt accumulation areas. To evaluate the effects of different planting methods on the quantity and quality of sugar beet in areas with salinity restriction, an experiment was carried out in a split split plot design in three replications in 2004-05, in Research Station of Rudasht, Isfahan. Irrigation with two salinity levels including 8 ds/m and 12 ds/m were allocated to the main plot, two planting dates to the subplots, and three planting methods including two rows under water mark, rows in flat plot, and on ridge to the subplots. Results showed that irrigation with 12 ds/m salinity level compared with 8 ds/m caused 17 and 18 % reduction in root yield and sugar content, respectively. Root yield was highly influenced by water salinity. Delay in planting, caused 31, 46 and 30% reduction in root yield, sugar content and sugar yield, respectively. Reduction in both white sugar yield and sugar yield was owing to root yield reduction. No significant difference was found among three planting methods. White sugar yield and sugar yield were higher in two- row planting method compared with two other methods. Delay in planting caused a significant decrease in sugar yield which is not recommended. Two- row planting method is recommended owing to more simplicity in irrigation, mechanized planting and also a decrease in production cost compared with two other methods.

In order to determine of the proper sowing date of steckling (rootlet) and harvesting date of seed, an experiment was conducted in Ardabil Agricultural Research Station (Alarough) in 2004- 05 growing season in split-plot in randomized complete block design arrangement with four replications. Four different planting dates viz. 5th March, 20th March, 4th April and 19th April– were allocated to the main plot and four harvest dates viz. 15, 30, 45 and 60 days to the subplots. The first harvest was conducted 15 days after 50% flowering to the subplots. Results showed that the maximum number of main stems (2.7 per plant) and lateral stems (42.4 per plant) were recorded on first and second planting dates, respectively. The plant height reduced from 128.03 cm (first planting) to 106.50 (4th planting). The highest raw seed yield and coefficient of standard seed extraction was achieved at the first planting date. The harvest date had a significant effect on raw seed yield, seed size and the percent of the empty seed. Also, the results showed that the highest raw seed yield (2735.8 kg/ha) and the percent of seeds with the size of 3.5- 4.5 mm (36.3%) was obtained from the 3rd harvesting date. The first harvesting date had the highest percent of the empty seed (17.2%). It is recommended that the beet steckling to be planted at the first possible date (in March) and the seed to be harvested at least 45 days after 50% flowering.. The total plant dry weight on first, second, third, and fourth planting dates were 389.6, 409.14, 344.9 and 300.9 g/plant, respectively. Among harvest dates, harvest at 45 days after flowering led to significant increase in plant dry weight, seed dry weight and seed yield (2735.8 kg/ha). Seeds harvested at 15 days after flowering had 60% of a normal seed size which was less than 3.5 mm (unusable) compared with seeds harvested at 45 days after flowering. Also, the highest rate of unfilled seed (%17.2) was obtained on the first seed harvest date.

This study aimed to modify the current purchase formula of sugar beet into a formula with different coefficients with respect to sugar percentage of autumn sugar beet. Ahvaz sugar factory was selected as an autumn sowing factory in Iran and 163 samples were randomly taken at different delivery times in 2007 (28th April to 27th June). From each truck, one sample was taken and sugar content, water content, marc, brix, reducing sugar, sodium, potassium, amino nitrogen, molasses sugars, and extraction coefficient of sugar were determined. Simultaneouly, results of all 4084 delivery samples during the campaign of the factory including 68801 tons beet belonging to three agro-industry companies and two contractors as well as Safiabad Agriculture Research Center, were statistically analyzed for sugar content (SC), soil tare, sugar beet price per tone and the paid price per vehicle. Results showed that average sugar content for all delivery vehicles was 12.84% (in the range of 10 to 15.20%) with standard deviation (SD) of 0.847. Average sugar content of Ahvaz factory was 3 units lower than the base price (16%) and 5.5 units lower than the average SC of the country in 2007 (18.29%). Average soil tare of the delivery vehicles (estimated visually) was 11.92% (in the range of 2 to 50%) with SD of 6.613. The average soil tare of Ahvaz factory was nine units greater than the country’s average in 2007 (about 3% for 4,282,805 tones of beets). Quality analysis, results showed that the average moisture content of delivery beets from autumn sowing in Khozestan province was 79% which was 4% higher than normal beet (75% moisture content or 25% dry matter). According to the results of this research and considering the potential of the region and with the aim at increasing the sugar content of the autum sowing sugar beet in Khoozestan, new formula for purchase price with three different coefficients was introduced for SC in the range of 10 to 24%. In this formula, the purchase price for each ton can be calculated by the following equations: a) SC of 10 to 15% {base price × (((SC×12) – 80))/100}, b) higher than 15 and equal to 20% {base price × ((SC×0.065) + 0.025)} and c) SC greater than 20% {base price × 1.325} and compared and analysed with the current formula assuming two units increase in sugar content. Application of the new formula with different coefficients with respect to SC is an important step in purchasing sugar beet based on quality, increasing the average SC of the region and consequently increasing the efficiency of the factory. So, this will support the farmers who are looking for the high quality sugar beet.

The main objective of this study was to develop an optimal cropping pattern for sugar beet growers in Fasa district (Fars province) and to investigate sugar beet importance in cropping pattern. Regarding the effect of risk on producer's decision, two risk sources including price and yield were considered. Data was obtained from Fasa district producers in 2008. In this study multi-objective mathematical programming was used. Results showed 7% difference between current income and optimal cropping pattern. However, they had difference in crop composition. In current pattern, 3.8 hectares out of 6.8 hectares belonged to sugar beet, while in optimal pattern, it reduced to 0.2 hectares. In general, in developed cropping pattern, sugar beet-wheat dominated production composition changes in favor of bean. These changes meet the goal of water use reduction up to 33% in addition to supply the current output. Results showed that farmers pay more attention to price risk in cropping pattern formulation. It was also determined that the inefficiency of sugar beet in using water as a restricting input has lowered its ranking in cropping pattern.