IRANIAN JOURNAL OF AGRONOMY AND PLANT BREEDING
Year:2014 | Volume:9 | Issue:4|Papers Count:12

This experiment was carried out to study on the effects of soil tillage methods on soil moisture conservation, growth indices, yield and yield components of some soybean cultivars. The experimental layout was RCBD in split plot arrangement with nine treatments and in three replicates conducted in research farm of university of Tehran with altitude of 1321 m ASL, longitude of 510 East, latitude of 350 48// North. The treatments included combination of soil tillage methods of conventional, minimum and no-till as main plots and soybean cultivars of Williams, Wojudanka and Verna as sub plots. According to the results tillage methods had significant effects (p<0.01) on grain yield, biomass, harvest index, number of cobs and number of seeds per cob and the minimum grain yield of 2593 kg ha-1was obtained from conventional system, while there was no significant difference between two other tillage methods. The biological yield in conventional system with the mean yield of 5994 kg ha-1 was more than two other tillage methods and the minimum biomass was obtained from minimum tillage. The maximum harvest index was observed in conventional system and the highest number of cobs per plant was obtained from Williams cultivar, while the number of seeds per cob was significantly different in studied cultivars with the highest amount in Williams and the lowest in Verna.

This research was carried out to determine of sugar beet sensitivity to water strees For 3 year. (2004-2006). We used Complete randomized block desigen with four replication and 5 treatment. Treatmens including: (I1): Irrigation with the amount of evaporation all stages of plant growth. (check) (I2): Implication of water stress at the stage of germination (from emergence to four leaves stages). (I3): Implication of water stress at the stage of development (4 leaves to completely covered). (I4): Implication of water stress at the middle stage. (completely covered to ripen bigining). (I5): Implication of water stress at the final stage. Irregations were done according to used availbe water by direct sampling from root elongation depth and water measurement by volom conture. the notes indicated in check treatment, necessary days have been over primary stage until development stage about 26-29 day and development stage pause have been about 39-42 day and middle and final stages have been respectively 55-60 and 60-65 days. Compound analysis of the data revaled that in moghan, if sugar beet encounters with water leakage and the elongation of irrigation cycle in middle stage due to hot weather summer days (up to 38oc) and resulted evaporation, root yield (51/39T/hec) and sugar percentage (10.6) are decreased. These results in comparision to other treatments and superior treatment without irregatioin in final stage with root yield of 59/5t/hec and sugar percentage of 12.80 are different. Ststistically the difference is sufficient in probability level of %5. the amount of sugar yield in surface unit with the implication of tretment 4 which is 5/5t/hec in comparision with treatment 5 (7/5t/hec) has sufficient differences.

In order to evaluate Reaction of Perko PVH to different levels of nitrogen and cutting in Karaj, an experiment was conducted in 2010-2011 at Mahdasht (Karaj, Iran). The first factor was different levels of nitrogen (100, 150, 200 and 250 kg/ha) and the second factor was cutting (1 and 2). Parameters of this study consisted of: plant hight, fresh forage yield, total dry matter, percent of protein and protein yield. Analysis of variance indicated that there were significant differences between nitrogen levels on plant hight, fresh forage yield, total dry matter, percent of protein and protein yield. Results showed that levels of cutting was significant effect on measured characters. The best of total dry matter were in 200 and 250 kg/ ha of nitrogen with 7.07 and 6.97 ton/ha. The highest percent of protein was on level of 250 kg/ha nitrogen with 24.67%.

In order to evaluating and grouping new maize hybrids based on morphological traits, 12 maize hybrids including medium and late maturing types (9 and 3 foreign and Iranian hybrids, respectively) were studied using completely randomized block design with four replications in Moghan region during, 2011. Analysis of variance revealed that there was significant differences among the hybrids for most of the studied traits. SC647 hybrid showed the highest grain yield among the hybrids, which was attributed by the highest 1000 grain weight and average number of grain row and grain per row. Cluster analysis using Ward's algorithm based on standardized data of the traits assigned the hybrids into two groups. Validity of grouping was confirmed by discriminant analysis. The hybrids grouping was consistent with pedigree information. Generally, the high variability was observed among hybrids. Hybrids SC647, SIMON, KORDUNA, NS770 and MAXIMA were grouped into cluster with high characteristics.

To determine the critical level of the micronutrients of Fe, Zn, Cu, Mn and B for the balanced consumption of chemical fertilizers keeping and improving the hygiene of the nutritions of the society increasing the quality and quantity of the field of wheat on the base of the research soil a test had been done in the city of Qazvin in 2007.First according to the width of the fields under the wheat cultivation that has been announced by the agriculture organization in distances of 2 km in the areas where soil sampling had been done then the features of the fields in the aspect of the width length and the altitude had been determined by the use of GPS.Due to the level of Fe, Zn, Cu, Mn and B in the soil the critical level of these elements had been computed by the use of the visual method of Cate-Nelson. On this research the critical level of Fe, Zn, Mn, Cu, and B were 3.75, 0.9, 1.65, 9, 1.05 mg/kg.According to the concluded critical levels in the straws that were suffering from deficient of Fe, the number of the grains were fewer, and finally it decreased the real function of the wheat.

One of the unique traits of plants is the conversion of the radiation energy into the chemical energy. Rapid canopy development and closure in crop increases interception of solar radiation and can be resulted in increases crop yield. Therefore, a study was conducted to investigate the relationship between canopy development on crop yield in soybean and determination of traits that affect canopy development. This study was conducted by using of eight soybeanars including Steel, BP, JK, Klark, Williams, Habit, Harcor and Hil in randomized complete blocks design with four replication in 2011. The results showed that rapid canopy development had significant effect on seed yield and cultivars with faster canopy development produced more seed yield. Leaf area index and crop dry matter at beginning of exponential growth phase and relative leaf area development rate and relative growth rate during the exponential phase, the average of individual leaf area and leaf area ratio were detected as effective traits in rapid canopy development.

Current research was conducted with the objective to evaluate the genetic variability for quantitative traits and their contributions towards grain yield as well as to identify the characters of utmost importance that may be used as selection criteria in a wheat breeding program under two water conditions. The experiment was laid out in a randomized block design with three replications in two separately fields in Gerize, Sanandaj during 2008-2009. Five statistical procedures including; simple correlation, stepwise regression, factor analysis, path analysis and cluster analysis were used to study the relationship between wheat grain yield and its components under two conditions. Results revealed that biomass, seed per spike and harvest index were the most effective variables influencing grain yield under well irrigated. While under drought stress biomass, grains per square and spike per square were the most important traits. Based on the results, it is reasonable to assume that high yield of wheat plants under drought conditions could be obtained by selecting breeding materials with high biomass, grains per square and spike per square.

This experiment carried out in order to investigation of biological traits and impact on yield and yield component in 8 cultivars of rice promising lines based on randomize complete block design, with 8 treatments and four replicate in rice research institute (Amol) in 2012 years. Cultivars effects on traits of plant height at raceme appearance time, plant height at maturity, number tiller at raceme appearance time, tiller number at maturity, 1000 grain weight, hollow grain percent in raceme, total grain number per raceme were significant at level 5%. In study of biological traits experiment cultivars, cv. Shirudi (Control) without consider sink and source limitation treatments, cultivars of 2, 6 and 7 designed in highest level, cultivars of 4 and 8 in the next level and cultivars of 1, 3 and 5 in third level. Finally cv.7 (Exp. cv.843) with plant height (97.37 cm) at raceme appearance time, plant height (116.4 cm) at maturity time, 19.5 tiller number at raceme appearance time, tiller number at maturity (15.75), 1000 grain weight (27 g), raceme length (26.75 cm), healthy grain percent (%82.53), hollow grain percent (%17.5) and total grain number per raceme (96.75) have been highest grain yield among cultivars.