Showing 126 results for Wheat
I. Zarrinabadi, P. Ehsanzadeh,
Volume 7, Issue 4 (1-2004)
Abstract
Despite its economic importance, not much information exists on growth and productivity of durum wheat in Iran and Isfahan. In order to evaluate growth, grain yield, and attributes in three durum wheat genotypes, Osta/Gata, Dipper-6, and PI40100, with five planting densities of 200, 275, 350, 425 and 500 seeds/m2, a four-replicate RCBD field study with a spilt-plot layout was carried out in winter 2000 to spring 2001 at Lavark Research Farm, College of Agriculture, Isfahan University of Technology. Genotypes were the main-plots and planting densities, the sub-plots. Each plot contained six rows, spaced 25cm apart, each 6m in length. While Osta/Gata produced a greater spikes/m2, 1000-grain weight and grain yield, PI40100 indicated a greater height, leaf area index (LAI) and biological yield, and Dipper-6 produced a larger number of grains per spike and harvest index, compared to the other two genotypes. Increasing plant density led to an increase in LAI, spikes/m2, grain yield, biological yield and harvest index but a decrease in grains/spike and 1000-grain weight. Grain yield was positively correlated with spikes/m2, grains/spike and 1000-grain weight, despite negative correlations with LAI and plant height. It may be concluded that with environmental conditions such as those encountered in Isfahan in 2000-2001, Osta/Gata can be planted at approximately 425 seeds/m2, if an acceptable grain yield is to be achieved.
S. Bahrami, M. Shahedi,
Volume 8, Issue 1 (4-2004)
Abstract
In this study, the effects of quality and quantity of protein in flours with 95% and 70% extraction rates obtained from Mahdavi and Tajan wheat cultivars each baked at two different durations (100 and 75 sec.) and temperatures (210 and 250°C), after wrapping in polyethylene packages with 40µm thickness were investigated. All tests were carried out during 168 hours after packing and at 24h intervals.
Results indicated that bread staling was affected by wheat cultivar, flour extraction rate, and storage time. Bread prepared from Tajan flour had lower firmness and staleness than that prepared from Mahdavi. High bran content bread was firmer than that with lower bran content. Organoleptic tests indicated that bread baked with 95% flour and bread baked at high temperatures with short durations were not very acceptable.
T. Mahmoodi-Ghehsareh, B. E. Sayed-Tabatabaei, C. Ghobadi, A. Mirlohi,
Volume 8, Issue 3 (10-2004)
Abstract
The significance of haploid plants as genetic and plant breeding tools has been recognized for a long time. Haploid production techniques including anther culture, isolated microspore culture and intergeneric hybridization between wheat × Hordeum bulbosum and wheat × maize have been used to produce homozygous lines which accelerate breeding programs. In this study, wheat × maize hybridization and anther culture techniques were used for haploid production in six wheat genotypes. The results showed that 70.7% of regenerated plants through anther culture were albino plants and only 29.2 % were green, while the plants produced through wheat × maize method were all green. Ploidy variation was not observed in plants regenerated through wheat × maize hybridization. It was concluded that wheat × maize crosses would be an appropriate and practical method for haploid production in different wheat genotypes, which in comparison with the anther culture method has a higher efficiency.
J. Niazi, H. R. Fooladmand, S. H. Ahmadi, J. Vaziri,
Volume 9, Issue 1 (4-2005)
Abstract
A research was conducted in Fars province Agricultural Research Center in Zarghan area from 1999 to 2002 to determine the water requirement and crop coefficient of wheat, applying lysimeter.
The results indicated that the water requirements of wheat were 720, 712 and 674 mm in the years of 1999-2000, 2000-2001 and 2001-2002, respectively. Using Penman-Monteith method for estimating reference crop potential evapotranspiration, the crop coefficients for wheat at a four-stage crop growth were 0.37, 0.64, 1.10 and 0.51, respectively. Due to the inaccessibility of the whole weather data, we tried to figure out a solution to determine wheat water requirement to schedule irrigation planning for future. In this respect, we made use of a ten-day class A pan mean evaporation and crop coefficient.
M . Hassani, G. Saeidi, A . Rezai,
Volume 9, Issue 1 (4-2005)
Abstract
A diallel analysis of eight bread wheat (Ttriticum aestivum L.) cultivars was conducted to determine genetic parameters and the type of genetic control for yield and yield components. The parents and their F1 hybrids were evaluated in a randomized complete block design with 3 replications. General and specific combining ability effects were estimated by the method 2 of the Griffings model I, and the genetic parameters were estimated by the Jinks-Hayman method. According to the analysis of variance, the variances of parents and crosses were significant for all of the traits, except for the fertile tillers per plant in parents and harvest index in crosses. The variance of GCA was significant for almost all of the traits. GCA to SCA ratio indicated a large additive effects for all the traits, except for the number of fertile tillers, grain yield per plant and biological yield. Darab and Chamran cultivars were the excellent general combiners for days to heading. However, Falat for plant height, Arvand for number of fertile tillers, spike length and grain weight per spike, Qods and Arvand for spikeletes per spike, Falat and Arvand for grain yield per plant and Qods and Arvand cultivars for biological yield were the best general combiners. Based upon the Jinks-Hayman method, the average degree of dominance for grain weight per spike, 1000- grain weight, grain yield per plant and biological yield indicated that these traits might be controlled by over dominance effects and other traits by partial dominance. The correlation between Yr and (Wr + Vr) for the flag leaf length, spikeletes per spike, grains per spike and 1000-grain weight indicated that recessive allels enhanced these traits. But dominant allels had their contribution to enhance other traits. The narrow-sense heritability for grain yield per plant (4%) and biological yield (14%) and harvest index (37%) was lower. However, for other traits it was more than 50%. Therefore, it can be inferred that indirect selection of grain yield through selection for yield components such as spikeletes per spike, grains per spike and grain weight per spike with high heritability and correlation with grain yield can be more effective.
M. M. Nakhjavani Moghaddam, B. Ghahraman,
Volume 9, Issue 3 (10-2005)
Abstract
In order to determine the water production functions for winter wheat (Variety, C73,5), an experiment was conducted in through of a complete randomized block design with 9 treatments and 3 replications in Mashhad region. While the first treatment (as a control treatment) was selected on the basis of irrigation in all growth stages of growing season, six treatments were selected on the basis of an irrigation cut in the six stages of growth season and two remaining treatments were also selected on the basis of a constant reduction of irrigation to the amount of 20 and 60 percent. In general the water stress was caused that the amounts of depth percolation were calculated negatively which was an indication of the water uptake from below the root zone. According to results, models of the yield in per unit of area had a higher correlation coefficient of determination in relation to the models of the yield in per unit of water. The derived sensitivity coefficients indicated that the winter grain formation and flowering stages were respectively the most sensitive stages of the growth season stages to the water deficit. There are some differences between these computed sensitivity coefficients and the amounts reported by the other researchers. Probably the variety, degree of stress, the climatic conditions and some unknown factors may explain these differences.
M. Eslami, S.a.m. Mirmohammady Maibody, A. Arzani,
Volume 9, Issue 3 (10-2005)
Abstract
To evaluate heritability, phenotypic and genotypic correlation coefficients, phenotypic and genotypic variances as well as relationships between some of the grain quality traits, an investigation was conducted in a randomized complete block design replicated three times in 2001, using four durum wheat genotypes PI40100, Dipper-6, Oste/Gata, Shova and their F2 and F3 progenies derived from their crosses. Grain quality characteristics including seed hardiness, protein content, SDS sedimentation volume and gluten content were evaluated. The results indicated that wet gluten content and dry gluten content had the highest coefficient of variation. Statistical analysis showed a significant difference between genotypes for all traits with the exception of SDS sedimentation volume. Dry gluten content had the highest heritability (90.4%) while SDS sedimentation volume had the lowest heritability (48.6%). Results of correlation analysis indicated that seed hardiness correlated significantly with protein content, SDS sedimentation and dry gluten content. Protein content had a positive correlation with wet and dry gluten content. Since dry gluten content showed a high correlation with protein content (quantity) and seed hardiness had a high correlation with SDS sedimentation volume, hence these two traits can be used as the selection criteria for improving quality of protein in durum wheat.
F. Momtazi, Y. Emam, N. A. Karimian,
Volume 9, Issue 3 (10-2005)
Abstract
The physiological characteristics of winter wheat(cv. Shiraz) were evaluated in a 2-yrs field study by using a spilit plot design with four replications, at the experimental farm of Shiraz University, College of Agriculture located at Badjgah. Main plots consisted of three sowing dates (November 6th, December 6th and January 5th) and four planting densities (150, 250, 350 and 450 plants/m2) were assigned as sub plots. The results indicated that delay in sowing was associated with a significant reduction in the grain yield. So that the grain yield in sowing date of January 5th was significantly less than it in sowing dates of November 6th and December 6th. Moreover with delay in sowing date the developmental rate of wheat was enhanced and plants reached maturity more rapidly. The trend of the leaf area index changes and the dry weight of the plants were under the effect of experimental treatments, leaf area index was found to be greater at the higher densities and early planting date. Number of stems per m2 were decreased with delay in the sowing date, although at the higher densities, the number of stems per m2 was greater, despite severe tiller death observed at these densities. The study of trend of dry weight changes during the season indicated that biomass was greater at higher densities and earlier sowings, which resulted in earlier ground cover and higher amount of radiation interception. In conclusion, the results of the present investigation revealed that to achieve a reasonable grain yield, the 6th of December and 250 plants per m2 were the best sowing date and planting density for wheat (cv. Shiraz) under similar agro climatic conditions with the present investigation.
Pourreza, M.r. Ebadi,
Volume 9, Issue 4 (1-2006)
Abstract
In a completely randomized design with 3×5 factorial arrangement, the metabolizable energy and nutrients digestibility of three varieties of sorghum grains (low, medium and high tannin) with and without supplemental phytase were determined and was compared with corn and wheat. Three varieties of sorghum were selected from the 36 varieties according to their tannin content and were grown togther with corn and wheat under the same environmental conditions. Supplemental phytase was added at three levels (0.0, 500 and 1000 FTU/kg) to each grain. The metabolizable energy (ME) and nutrients digestibilities were determined by the mature male Leghorn with the method of Sibbald. The results indicated that different grains had different ME, apparent and true digestibilities regarding dry matter, nitrogen and phosphorus. Medium tannin sorghum had the highest apparent and true metabolizable (AME and TME) energy, whereas the high tannin sorghum showed the lowest AME and TME. The apparent and true dry matter digestibilities of corn was more than the other grains (P<0.001). Medium tannin sorghum had the highest apparent and true nitrogen digestibilies than the other two varieties (P<0.001). Difference between tested grains regarding apparent and true phosphorus digestibilities were not significant. All measured criteria were the lowest for the high tannin sorghum. Adding 500 FTU/Kg phytase caused an improvement (P<0.001) in AME, apparent and true dry matter digestibilities and true nitrogen digestibility. Although added phytase improved apparent and true phosphorus digestibilities and true nitrogen digestibility, but the differences were not significant. The differences between 500 and 1000 units phytase was not significant and the results indicated that 500 FTU/Kg phytase was sufficient to improve the nutritional value of grains under study.
A. R. Ommani, M. Chizari,
Volume 10, Issue 1 (4-2006)
Abstract
The main objective of this article is to present the results of a study done about the social, economical, and farming characteristics of wheat farmers in Khuzestan province of Iran regarding adoption of low input sustainable agriculture (LISA). LISA practices have tended to reduce the use of fertilizer pesticides, and maximal tillage, but, rely more on crop rotation, crop residues, animal manure, green manure, leguminous, appropriate mechanical cultivation or minimal tillage to optimize soil and natural pest control activity. The research design was a descriptive and correlation surveying method. Wheat farmers in Ahvaz, Behbahan, and Dezful township of Iran who cultivated wheat by the use of irrigation in the year of 1379-80 were the target population for this study. A random sample of wheat farmers selected from three randomly selected township of Ahvaz, Behbahan, and Dezful township (N = 5529 , n = 359 ). The main results of the study indicated that correlation of level of education, wheat land, ownership land , income, social participation, social status, social norm, technical knowledge, LISA knowledge, with adoption LISA practices were significantly positive and the correlation of age, experience in agriculture, distance between farm and service centers with adoption LISA practices were significantly negative.
M. Borji,
Volume 10, Issue 2 (7-2006)
Abstract
Recently, the use of microorganisms for conversion of plant biomass into many commercially valuable products has been studied. In this study, some soil samples, composting plant materials, and composted manure from different parts of Markazy province were collected to isolate and identify aerobic bacteria, which have been capable of utilizing lignin preparations as a sole source of carbon. Bacteria were isolated by using three types of lignin preparations and hot- water- extracted wheat stover and saw dusts. Two of the isolates, identified as Streptomyces sp. and Pseudomonades sp. were able to degrade wheat stover and saw dust lignin and polysaccharides. The growth rate of Streptomyces sp. and Pseudomonades sp. was higher in wheat stover fed cultures than the saw dust fed cultures. Results also showed that bacteria treatment of lignocelluloses and nitrogen supplementation of culture media had considerable effects on chemical composition of wheat stover and saw dust. All two bacteria genera increased crude protein, APPL, soluble lignin, and decreased carbohydrates and insoluble lignin of wheat stover and saw dust (P<0.01). Streptomyces showed more degradation ability than Pseudomonades, especially in culture media containing wheat stover. The utilization of yeast extract (as nitrogen source) improved degradation abilities of bacteria. The findings of this study indicate that these bacteria could be used for biological upgrading of agriculture residues in order to feed animals.
B. Heidari, A. Rezaie, S. A. M. Mirmohammadi Maibody,
Volume 10, Issue 2 (7-2006)
Abstract
Diallel analysis was used to estimate the combining ability, gene action, gene number, heritabilties and other genetic parameters of a set of wheat genotypes. For this purpose, nine parents and their 36 crosses were evaluated for 9 traits in a randomized complete block design with three replications in 1996. The analysis of variance revealed significant differences among all genotypes for all traits. Estimates of general and specific combining ability mean squares based on Griffing’s Method 2 indicated the importance of additive and non additive effects in the expression of all traits. Alvand and Roshan cultivars for grain yield per plant, Alvand for grain number per main spike and main spike weight, and Alvand and Alamoot for 1000 grain weight were the best combiners, thus use of them is beneficial for these traits. Based on the estimates of average degree of dominance and results of graphical analysis, the gene action for grain number and spikeletes per main spike were partial dominance, while for grain yield per plant, biological yield, plant height, harvest index and 1000 grain weight, overdominance gene actions were observed. Moreover, genotypic correlation coefficients of grain yield per plant with grain number per main spike, 1000 grain weight, grain weight per main spike and main spike weight were positive and significant.
M. Salehifar, M. Shahedi, Gh. Kabir,
Volume 10, Issue 2 (7-2006)
Abstract
Bread is widely consumed as a staple food all over the world. The major ingredient of bread is wheat flour which suffers of a couple of shortcomings, such as essential amino acids. To overcome of this problem, a great deal of attention has been made by fortification of bread with different cereal and legume flours. In this study, wheat flour was replaced with 0, 10, 20, 30 and 40% of oat flour to investigate of its effects on dough texture and sensory attributes at room and lower temperatures for 0, 24, 48, 72 h in improved and unimproved breads. Improved formula containing levels of blanched oats, 1.5% fat and 60 ppm ascorbic acid. Addition of oat flour improved bread shelf life. Breads baked with up to 20% oat flour, were considered to be stable along over the time as indicated by sensory evaluation. Samples substituted with 30% and 40% oat flour had the high intensities of bitterness.
M. A. Nazari, H. Shariatmadari, M. Afyuni, M. Mobli, Sh. Rahili,
Volume 10, Issue 3 (10-2006)
Abstract
Sewage sludge and effluents, as cheap sources of irrigation water and fertilizer, can supply plants with water and nutrients however, contamination of these sources with heavy metals and the possibility of human food chain contamination using these sources should be considered. In this research, the effects of industrial sewage sludge and effluents on concentration of some nurtients, heavy metals and sodium and dry matter yield of wheat (Triticum aestivum), barley (Hordeum vulgare) and corn (Zea mays) were investigated. The experiment was carried out in a greenhouse using a complete randomized design with four replication. The treatments comprised well water, well water + sewage sludge(50 tons/ha), and three industrial effluents from Iran Polyacryl factory including the cooling tower, the over flow and the factory outlet effluents. Chemical analysis showed the following results: The concentration of the elements in the sludge and the effluents were below the critical contaminating levels. The application of the treatments did not supply enough nitrogen for corn the cooling tower effluent could not supply enough nitrogen for wheat and barley all the treatments supplied enough P for wheat. None of the treatments could supply enough P for corn. The cooling tower, over flow and the factory outlet effluents could not supply enough P for barley, the micronutrient and heavy metal concentrations in the plant tissues using the effluents and the sewage sludge were higher than those for well water the dry matter yield of plants’roots and shoots was highest using well water + sludge and in comparison with the well water, effluents could increase the shoot dry matter yield.
A. Azizian, A. R. Sepaskhah, A.r. Tavakoli, M. Zibaee,
Volume 10, Issue 4 (1-2007)
Abstract
Irrigation water Scarcity is the major limiting factor for crop production in irrigated farming. Therefore, optimal use of water is influenced by seasonal rainfall especially where the water price is high. Nitrogen also plays a key role in plant nutrition. In this study, wheat grain yield production as a function of applied water (irrigation plus seasonal rainfall) and nitrogen fertilizer (applied plus soil residual nitrogen) using existing data of a field experiment, were used. This function was obtained based on the data from the Maraghah Agricultural Experiment station. Based on this production function, maximum attainable yield can be 8.12 t/ha obtained by the consumption of 1.56 m of water (irrigation plus rainfall) and 193 kg/ha of nitrogen. An economic analysis based on the Iso-Quant curve was conducted to optimize the application rates of production inputs (water and nitrogen). When land is limited, the optimum water and nitrogen use will be based on maximizing net returns from land unit area. The optimal levels of these inputs were determined on the basis of farmer ability for paying the costs of water and nitrogen. Furthermore, optimum amounts of water and nitrogen were determined for different levels of wheat yield. The results indicated that despite low price of irrigation water and nitrogen fertilizer, at present market value, optimum values of water were more variable than those of nitrogen, for its high effective role in wheat production. The results also indicated that when there is no limitation of the source and use of water and nitrogen, and farmers are also able to pay their costs, application of 1.47 m of water (irrigation plus rainfall) and 190 kg/ha of nitrogen (applied plus soil residual) will produce maximum profit per hectare, reaching Rls 12,207,506. When water is limited, optimum levels of water and nitrogen will be based on the maximizing profit per unit of water. In this analysis, the use of 0.556 m of water (irrigation plus rainfall) and 190 kg/ha of nitrogen (applied plus soil residual) resulted in maximum net income per unit of applied water (irrigation plus rainfall) amounting to Rls/m3 1203. This amount of water use, which is 64.4 % lower than its amount under maximum yield condition, resulted in 181 % increase of cultivated area. Graphic expansion path on the isolines of yield showed more dependence of wheat production on water than nitrogen. Therefore, the optimum amounts of nitrogen in the three mentioned conditions are close to each other due to its subsidized price and lower effect on wheat production relative to water.
A. Ghanbari, J. Abedi Koupai, J. Taie Semiromi,
Volume 10, Issue 4 (1-2007)
Abstract
A field study was conducted at the Zabol Agricultural Research Center during the years (2003-2004) to investigate the effect of irrigation with treated municipal wastewater on the yield and quality of wheat and some soil properties. Irrigation treatments were: T1: Irrigation of wheat with well water during entire period of growing season T2: Irrigation of wheat with well water until the begging of flowering stage, and irrigation with wastewater in every other turns of irrigation T3: Irrigation of wheat with well water until the beginning of booting stage, and irrigation with wastewater in every other turns of irrigation T4: Irrigation of wheat with well water until the begging of tilling stage, and irrigation with wastewater in every other turns of irrigation and T5: Irrigation of wheat with wastewater during entire period of growing season. A complete randomized block design with four replications was adopted for this experiment. The soil was sandy loam with no limitation for internal drainage. Chemical and physical aspects of soil were measured during the experiment. Grain yield, yield components and chemical composition of wheat grain were also measured. The results showed that yield of wheat and total biomass production were statistically significant in T3, T4 and T5 compared with the control treatment. Plant height, width and length of flag leaf, numbers of fertile tillers, length of panicle, numbers of grains per panicle and weight of 1000 grains were also statistically significant with the control treatment. Percentages of protein were statistically different among various irrigation treatments. No significant changes in accumulation of heavy metals in soil and plant grains were observed. The increase of SAR, ECe, O.C% and total nitrogen in the T4 and T5 were statistical significant compared with the control treatment. In summary, for sustainable use of Zabol municipal wastewater, the growth stages of wheat should be irrigated with municipal wastewater and other growth stages should be irrigated with nonsalinty water, so that the maximum yield is obtained and soil salinitisation and sodication is prevented.
A. Jalalian, J. Givi, M. Bazgir, Sh. Ayoubi,
Volume 10, Issue 4 (1-2007)
Abstract
In Iran, the development of cultivated areas becomes gradually impossible due to ever-increasing population growth and urban area development. Therefore, it is very important to use the existing cultivated lands more efficiently. Land suitability evaluation makes the sustainable use of the lands feasible. The objective of this study was qualitative, quantitative and economic assessment of land suitability in Talandahst area for rainfed wheat, barley and chickpea. Talandasht plain with a surface area of 4500 ha is located southwest of Kermanshah city. The climate is semi-arid with cold winter and moderate summer. The successive stages of this research included soil survey in the field, soil analysis, qualitative and quantitative and economic evaluations of land suitability. In qualitative evaluation of land, climatic, topographic and soil suitability classes were determined according to the degree of the matching. Limitation and parametric methods were used in qualitative evaluation. Quantitative and economic evaluations made based on the observed yield and gross benefit, respectively. Based on qualitative evaluation, the studied area is marginally suitable for rainfed farming of wheat, barley and chickpea. This is due to water deficiency occurring during some stages of the growing cycle. The solution for this problem is supplementary irrigation. In addition to climate limitation, there are also topographic and soil restriction for the growth of the studied crops. On the basis of observed yield, the land units are moderately to highly suitable for rainfed wheat and barley production. Among the three named crops, the most and least profitable ones are chickpea and barley, respectively, and wheat ranks between them.
M .tousi Mojarrad, M. R. Ghannadha,
Volume 10, Issue 4 (1-2007)
Abstract
In order to evaluate grain yield potential and study dry matter remobilization to seed, 8 commercial bread wheat cultivars were examined in two separate experiments, using randomized complete block design with 4 replications in 2003. There were significant differences for most traits in normal and drought conditions. Sarday variety had the least grain yield in the two environments. There was considerable variation between genotypes for independent parameters of dry matter remobilization to different plant parts in the two environments. Factor analysis showed that seven factors accounted for 100 % of the data total variance in normal and drought conditions. Factor analysis also showed that the effective traits to components grain yield , height and phenological traits were important for the selection of appropriate genotypes. Calculation of drought resistance indices showed that four indices including mean productivity, geometric mean productivity, harmonic index, stress tolerance index were more effective than other indices for the selection of drought tolerant genotypes.
E. Farahani, A. Arzani,
Volume 10, Issue 4 (1-2007)
Abstract
An experiment was conducted to investigate the genetic diversity in the cultivars and F1 hybrids of durum wheat, using agronomic and morphological traits. Evaluation of consistency between choosing parents of crosses based on morphological and agronomic observations and genetic distance obtained from cluster analysis were objectives of this study. Fourty- two genotypes were evaluated using a randomized complete block design with three replications in 2003. Agronomic characteristics comprised days to 50% flowering, days to 50% pollination, days to maturity, plant height (cm), spike length (cm), grain weight per spike (gr), number of grain per spike, number of spike per m2, grain yield (t/ha), biological yield (t/ha), 1000 grain weight, test weight (gr/L) and harvest index were measured in the studied genotypes. The results of analysis of variance showed significant differences among genotypes for all the studied traits. The results also revealed that grain yield had the highest coefficient of variation (CV= 21.6%), followed by spikes per m2 (CV= 20%) and number of grains per spike (CV= 18.9%). Lowest coefficient of variation was observed in days to maturity, days to 50% pollination and days to 50% flowering. Moreover, correlation analysis indicated that grain yield correlated with harvest index, biological yield, grain per spike and grain weight per spike. Cluster analysis of genotypes based on agronomic traits defined desirable clusters. These clusters have desirable characteristics and are beneficial for breeding objectives. Results of evaluation of consistency between choosing parents based on observation and those of cluster analysis showed varing degrees of consistency in 12 conducted crosses, ranging from highly similar parents in Eupoda6×Chahba88 to relatively distinct parents in PI40100×PI40099 cross.
N. Sahebani, A. Kheiri, H. Rahimian, A. Sharifi Tehrani,
Volume 10, Issue 4 (1-2007)
Abstract
The effect of Rathayibacter tritici on the movement of Anguina tritici larva and nematode function as vector of ear rot bacterium was conducted in the laboratory (Agarose plates) and greenhouse conditions. The results showed that the contact of nematode larva with high concentration of bacterium or long duration of nematode-bacteria contact can decrease the movement and the efficiency of nematode function as the vector of the disease, and in some cases it resulted in the mortality of the nematode. No differences were detected in the mobility of larva in the concentrations less than 102 CFU and less than 0.5 hour of nematode-bacteria contact times and their controls (exposed to water alone). Movement of the nematodes appeared to be random under these conditions. It can be concluded that Rathayibacter tritici did not act as an attractant to Anguina tritici larva. These results suggest that the attachment of a large number of bacteria to nematode (as an essential vector of the bacterium) would induce nematode weakness and mortality. So it is possible that ear rot bacterium can parasite ear cockle nematode, or the nematode is a host for this bacterium .