Showing 171 results for Yield
Y. Raei, M. Sedghi, R. Seied Sharifi,
Volume 12, Issue 43 (4-2008)
Abstract
A factorial experiment, based on RCB design, with three replications was conducted to evaluate the effects of rhizobial inoculation, urea, and weeds on soybean performance in the field. The factors under study consisted of inoculation and non-inoculation, three levels of 0, 150, and 300 kg/ha urea, and weed-control and weed-infestation. Results showed that weed-control, inoculation and urea application increased biological and seed yield. The highest effect on yield was due to weed control, followed by inoculation and urea application. Inoculation, weed-control and urea application of 300 kg/ha enhanced protein percentage in soybean grains. In this case, inoculation had the highest effect on protein percentage, followed by urea application and weed control. In contrast, only weed-control significantly increased seed oil percentage. Seed filling rate increased as a result of inoculation, but, seed filling duration was not affected by inoculation. Weed-control improved seed filling rate and duration. Urea application induced seed filling duration, but had not any effect on seed filling rate.
R. Karimizadeh, M. Safikhani Nasimi, M. Mohammadi, F. Seyyedi, A.a. Mahmoodi, B. Rostami,
Volume 12, Issue 43 (4-2008)
Abstract
One of the applications of Non-Parametric methods is determination of genotypes rank in different environments, which is also used as a measuring stability. A stable genotype shows similar ranks across different environments and has minimum rank variance in different environments. Non-Parametric Stability Statistics require no statistical assumptions about the distribution of the phenotypic values and are easy to use. This study was carried out to determine the ranks of 10 Lentil genotypes (Lens culinaris Medikus) across ten environments in 2002-2004, using a randomized complete block design with four replications. Analysis of Thennarasu non-parametric statistics showed that genotypes 8 and 9 had high stability by NP(1) statistic and genotypes 9, 8 and 1 had stable yield in NP(2) method. Result of the NP(3) statistic was similar to NP(1) statistic. NP(4) statistic selected genotypes 9 and 1 as the most stable genotypes and ultimately NP(5) statistic introduced 9 and 1 genotypes as stable genotypes in this experiment. Also analysis of Nassar and Huhn non-parametric statistics revealed that genotypes 1 and 2 were most stable and well adapted across ten environments. In addition, it was concluded that plots obtained by both mean yield (kg ha-1) vs.Si(1) and mean yield (kg ha-1) vs. Si(2) values could enhance visual efficiency of selection based on genotype × environment interaction. According to these configurations, genotypes in section 1 can be considered as stable and well adapted to all environments, having general adaptable ability. For recognition a daptability,Si(1) and Si(2) take preferred over other non-parametric statistics.
M. Salehi , R. Akbari , M.b. Khorshidi Benam,
Volume 12, Issue 43 (4-2008)
Abstract
In order to determine the response of yield and seed yield components of red bean )Phaseolus vulgaris L. ( genotypes to delay in planting, this study was conducted in Factorial experiment based on a RCB design with 3 replications in the Jahad-Keshavarzi Research farm of Miyaneh in 2006. Factors included cultivars in three levels(Naz, Gole and Sayad) and planting date in three levels (5 and 20 April, and 5 May). Results of variance analysis showed that the cultivars and planting dates had significant effects on all the characteristics. The interaction between cultivars and planting dates had significant effect on stem height, number of pod per plant, 100 seed weight, biological yield, grain yield and number of seed in pod. The Results of mean comparison indicated that SAYAD cultivar in the first planting date with 4033.3 kgha-1 and Gole cultivar in the third planting date with 1500.2 kgha-1 had the highest and lowest grain Yield, respectively. Total yield with all traits, except for the stem height, 100 seed weight and cultivar protein percentage showed a positive and significant correlation.
E. Rahmani, A. Khalili, A. Liaghat,
Volume 12, Issue 44 (7-2008)
Abstract
The growing season climatic parameters, especially rainfall, play the main role to predict the yield production. Therefore, the main objective of this research was to find out some possible relations among meteorology parameters and drought indexes with the yield using classical statistical methods. To achieve the objective, ten meteorological parameters and twelve drought indexes were evaluated in terms of normality and their mutual influences. Then the correlation analysis between the barley yield and the climatic parameters and drought indexes was performed. The results of this study showed that among the drought indexes, Nguyen Index, Transeau Index, Rainfall Anomaly Index and Standardized Precipitation Index (SPI24) are more effective for prediction of barely yield. It was also found that the multivariate regression is better than the univariate regression models. Finally, all the obtained regression models were ranked based on statistical indexes(R,RMSE and MBE). This study showed that the multivariate regression model including wind speed, sunshine, temperature summation more than 10, precipitation and Nguyen index is the best model for prediction yield production in Miane. Average wind speed and Nguyen index were recognized to be the most effective parameters for yield production in the model.
N. R. Jalali, M. Homaee, S. Kh. Mirnia,
Volume 12, Issue 44 (7-2008)
Abstract
Canola (Brassica napus L.) in response to salinity represents various resistances with respect to its phonologic stages. Most plants such as Canola are resistant at germination stage. However, at seedling or earlier growth stages, plants become more sensitive to salinity but their tolerance increases with age. Salt tolerance of various plants has been extensively studied however, the results have either been qualitative or expressed as average values over root zone salinity for the whole growth season. Thus, developing appropriate models for quantitative characterization of plant response to salinity at different growth stages is essential. Canola which is considered as high economic value plant was selected for this study. Two productive stages for canola are recognized as flowering and ripening. To determine the effect of salinity on canola at vegetative growth stages, a greenhouse experiment was conducted on a natural saline loamy sand soil, using salinity treatment including one non-saline water (tap water) and 8 saline waters of 3 to 17 dS.m-1. The canola plants were irrigated with tap water before the desired stage and then salinity treatments were imposed. The Maas and Hoffman (1977), van Genuchten and Hoffman (1984), Dirksen et al., (1993), and Homaee et al., (2002b) models were used to predict relative transpiration (Ta/Tp ) and relative yield ( Y/Ym) as a function of soil salinity. The maximum error (ME), root mean square error (RMSE), coefficient of determination (CD), modeling efficiency (EF) and coefficient of residual mass (CRM) statistics were calculated to compare the models and their efficiencies. The results indicated that the van Genuchten and Hoffman (1984) model provides best prediction at flowering stage. However the Homaee et al. (2002b) model offers better prediction at ripening growth stage.
Gh. Saeidi, A. Sedghi,
Volume 12, Issue 45 (10-2008)
Abstract
Rapeseed (Brassica napus L.) is one of the oilseed crops in the temperate regions and is adapted to different climate conditions. This crop can have an important role in production of vegetable oil, and providing appropriate soil fertility can increase its seed and oil yield. In order to investigate the effect of N, P, K, Fe, Zn and Mn on seed yield and other agronomic traits of rapeseed, an experiment was carried out at the Research Farm of Isfahan University of Technology in 2006. The experiment was arranged as split plot in a randomized complete block design with three replications in which eleven fertilizer treatments and two cultivars of rapeseed (Ocapi and Zarfam) were considered as the main and sub factors, respectively. The results showed that there was no significant effect of fertilizers on days to maturity, but application of NPK+Fe significantly increased the plant height in both cultivars. The fertilizer treatment had no significant effect on the number of pods per plant and seeds per pod. The interaction effects indicated that application of N, P, K, NP and NK significantly increased 1000-seed weight in Ocapi cultivar however NPK+Fe significantly decreased 1000-seed weight and non significantly increased seeds per pod in Zarfam cultivar. Application of N, NPK and NPK+Fe increased the seed yield by 13, 7 and 43%, respectively. Averaged over two cultivars, N significantly increased seed oil content, but significant interaction between fertilizers treatments and cultivars indicated that application of K and NP significantly reduced the seed oil content in Zarfam cultivar. Fertilizer treatments of N, NPK and NPK+Fe had higher effects on seed oil content and oil yield and means of these traits for fertilizer treatments of control, N, NPK and NPK+Fe were 39.7, 41.7, 39.4 and 39.8%, and 681.1, 816.4, 730.2 and 983.3 kg/ha, respectively which indicate that N and Fe increased the seed and oil yield in both cultivars. However, the application of Zn and Mn had no significant effect on seed yield and seed oil content. In this study, the variation of seed yield and oil yield was mainly due to the variation of number of pods per plant and seed yield, respectively. In conclusion, it seems that in soil and climatic conditions like this experiment, application of N and Fe can be economically important and increase the seed and oil yield in rapeseed.
S. M. Naser Alavi, M. Shamsaddin Saeid,
Volume 12, Issue 45 (10-2008)
Abstract
To study the effects of plant densities and planting orientation on the seed and forage yield of sorghum, an experiment was conducted at Hossein- Abad – Shahcal village –90 kilometers south of Bam-in 2002. The experiment was a factorial with randomized complete block deisgn and three replications. The treatments were: orientation with three levels (South-North, East – West, Northeast – Southwest) and plant densities with four levels (50000, 70000, 90000, 110000 plants per hectare). Results of analysis of variance showed that planting orientation had significant effects on seed yield, weight of 1000 seeds, number of tillers, dry matter yield, length and diameter of shoot. Mean comparisons, showed that the maximum and minimum amount of the above mentioned traits except for shoot length was obtained under the North-South and East-West orientations, respectively. Significant differences were also found among densities in terms of all the mentioned traits. Results showed that increasing density decreased seed yield, weight of 1000 seeds, number of tillers and shoot diameter. The highest and lowest values (except of seed yield) were recorded for 50000 and 110000 plants/per hectare, respectively. Dry matter yield and the shoot length increased with increasing density. Based on the results of this experiment, the best plant densities to obtain the highest forage and seed yield are 70000 and 110000 plant per hectare, respectively and the best planting orientation is North-South.
S. Fallah,
Volume 12, Issue 45 (10-2008)
Abstract
To study the effects of planting date and density on yield and its components in chickpea (Cicer arietinum L.) genotypes under dryland conditions of Khorram-Abad, an experiment was conducted during 2005-2006 growing season at the Agricultural Research Station of Lorestan Weather Department. Three sowing dates (March 6, March 21, and April 5) and two chickpea genotypes (Greet and Flip 93-93) with four plant densities (18, 24, 30 and 36 plants m-2 ) were evaluated using a randomized complete block design with split-factorial design in three replications. Dates of planting were considered as the main plots, genotypes and plant densities were randomly distributed in sub-plots with factorial arrangement. The result showed that delay in planting from March 6 to April 5 significantly reduced number of pods per plant, number of grains per pod, 100-grain weight, grain yield and dry matter. Increasing plant density led to a significant decrease in number of pods per plant, number of grains per pod and 100-grain weight. However, grain yield and dry matter increased firstly with increasing plant density and then decreased. Planting date and density had no significant effect on harvest index, while genotype of Greet produced a larger number of pods per plant, grain yield as well as final dry matter. Also Flip93-93 produced a bigger number of grains per pod, greater grain weight and harvest index. The maximum grain yield was obtained with genotype of Greet at the first planting date in 30 plants m-2 density. It could be concluded that due to thermal and drought stress occurring in late spring,, early planting of Greet genotype at 24-30 plants/m2 may lead to a suitable increase in grain yield.
P. Heydarizadeh, M. Sabzalian, M.r. Khajehpour,
Volume 12, Issue 45 (10-2008)
Abstract
During recent years, several genotypes have been selected from Isfahan land race Kouseh. The performance of safflower selected genotypes was studied in the field conditions, at Agriculture Research Station, Isfahan University of Technology during 2003. The experiment was carried out using a split plot arrangement according to a randomized complete block design with three replications. Planting dates (March 11, April 20, May 22 and June 23) were considered as the main plots and subplots consisted of 20 genotypes of safflower including 19 selections from Kouseh and Arak-2811 genotype. Days from planting to emergence and emergence to stem elongation were reduced as planting was delayed until the fourth planting date. Days from stem elongation to head visible was reduced with delay from the first to the third planting date, and then increased. Days from head visible to 50% flowering was reduced with delay from the first date to the third planting date, but increased in the fourth planting date. Days from 50 percent flowering to physiological maturity was increased with delay in planting. Days from planting to emergence, emergence to stem elongation, stem elongation to head visible and 50 percent flowering to physiological maturity were not influenced by genotypes. Genotype DP7 had the highest and genotype C111 and genotype DP25 had the lowest days from head visible to 50% flowering. The interaction between planting date and genotype in regard to days from stem elongation to head visible was also significant. Seed weight per plant was reduced with delay in planting date. Genotype ISF66 had the highest and genotype Arak-2811 had lowest seed weight per plant. The number of days from emergence to head visible in ISF66, DP5, C128 and Arak-2811 was affected by maximum temperature (Tmax), in genotype DP7 by Tmax2, in genotypes DP17, DP1 and C41100 by Tmin2 and in genotypes DP9, DP25, ISF28, ISF22, and C111 was affected by day length. It seems that development period from emergence to head visible was affected by temperature in the most genotypes. On March 11 planting date, genotypes had the maximum response to temperature and day length and the minimum response was observed in the fourth planting date. The genotype ISF66 had the highest seed yield on March 11 planting date. The result of this study showed that safflower should be planted in late March under condition similar to this experiment for maximum yield production.
G. Saeidi,
Volume 12, Issue 45 (10-2008)
Abstract
This study was conducted to investigate the effects of thirteen fertilizer treatments (as main factor) on agronomic traits of two local cultivars (as sub factors) of sesame (Sesamum indicum L.), "Mobarakeh" and "Ardestan" in Isfahan by using a randomized complete block design with three replications. The results showed that applying fertilizer treatments of N, P, K, Fe, Zn and Mn had no significant effects on yield components, seed yield and oil yield. However, comparing the control treatment, simultaneous application of all fertilizers significantly reduced days to maturity. Significant interaction between cultivars and fertilizer treatments was observed for seed oil content, as application of N, P, NPK and NPK+Fe+Zn in Mobarakeh and application of N+K in Ardestan reduced seed oil content. However, the other fertilizer treatments had no significant effects on this trait. The Mobarakeh cultivar compared to Ardestan had significantly higher plant height, higher seeds per capsule, lower 1000-seed weight, higher seed yield per plant and per hectare and higher oil yield. Seed yield for Mobarakeh and Ardestan cultivars were 1646 and 1169 kg/ha and their seed oil contents were 52.88% and 53.81%, respectively. The correlation coefficients and regression analysis showed that the variation of seed yield was mostly due to the number of capsules per plant and seeds per capsules, thus these two traits were the most important yield components. Oil yield had a very high correlation coefficient with seed yield (r=0.99**), whereas its correlation with seed oil content was very low (r = -0.10ns). Therefore, it seems that seed yield was the main cause of higher oil yield.
M. Dehghanian, M. Madandoost,
Volume 12, Issue 45 (10-2008)
Abstract
In order to investigate the effect of zinc - chelate on drought tolerance of Azadi cross wheat, a randomized complete block design was conducted as split plot with three replicates in the Kherameh during 1383 - 1384. The main plot was four drought levels (control and drought stress in the stages of flowering, seed milk stage and two phases, together), and sub plot was zinc - chelate rates 0, 5, 10 & 15 kg per hectare. The results showed that zinc application under drought conditions increased spike per square meter significantly at the 5% level. Drought stress decreased 1000 - seed weight. Least of 1000 - grain weight was in two phases of flowering and seed milk stage together (29.78 g). The application of 15kg zinc -chelate fixed 1000 - seed weight. Treatments of drought stress decreased seed yield significantly (14.17% in the proportion of control), but zinc - chelate application increased wheat tolerance to seed yield decrease. Zinc - chelate application prevented from seed number decrease per wheat spike under drought conditions that was caused to tolerance of seed yield and harvest index decrease. The application of 15 kg zinc - chelate increased harvest index in comparison of control amount of 22%.
S.s. Pourdad, K. Alizadeh, R. Azizinegad, A. Shariati, M. Eskandari, M. Khiavi, E. Nabatee,
Volume 12, Issue 45 (10-2008)
Abstract
Safflower (Carthamus tinctoius L.) is an Iranian native crop that is adapted to different environmental conditions of this country. Sixteen safflower varieties/lines were spring-planted in 6 research stations including Sararood (Kermanshah), Maragheh, Ghamlo (Kordestan), Khodabandeh (Zanjan), Shirvan (North Khorasan)and Khohdasht (Lorestan) with and without drought stress conditions each in a RCBD with 3 replications. Some drought resistante indices including Mean of Productivity (MP), Geometric Mean of Productivity (GMP), Tolerance (TOL), Stress Tolerance Index (STI), Stress Susceptibility Index (SSI) for seed yield and genotypes Cell Membrane Stability (CMS) were calculated. Results showed that STI was the most appropriate index to identify drough resistant genotypes. Estimation of STI from mean of all stations revealed that Gila, CW-4440 and PI-537598 with high STI showed high seed yield in both stress and non-stress conditions. Caculation of STI standard deviation for these genotypes showed that Gila had less STI stability over the locations than other two genotypes so, CW-4440 and PI-537598 are more stable in drought stress resistance. Analysis of variance for cell membrane stability (CMS) of genotypes showed the significant differences in 1% level of probability between genotypes. S-541 had the highest and Kino-76 had the lowest CMS. There were significant and strong correlations between STI, MP and GMP with CMS namely, genotypes with more stable membrane having more drought resistance in field condition. So, cell membrance stability can be a useful and fast method to screen germplasm and identify drought resistant genotypes. Cluster analysis based on STI,MP,GMP, CMS and seed yield in both stress and non-stress conditions divided genotypes into 3 groupes. Results of clustering also identified S-541, Gila, CW-4440 and PI-537598 as 4 superior genotypes and confirmed the results of other methods.
M. Majidian, A. Ghalavand, N. Karimian, A. A. Kamgar Haghighi,
Volume 12, Issue 45 (10-2008)
Abstract
In order to investigate the effects of moisture stress, nitrogen fertilizer, manure and integrated nitrogen and manure fertilizer on yield, yield components and water use efficiency of SC 704 corn (late maturing, non-prolific and dent). In 2005, a field study was conducted in agricultural experiment station of the college of agriculture, Tarbiat Modares University. The type of design was randomized complete block with factorial arrangement and three replications. For the study, four levels of nitrogen fertilizer (0, 92, 184 and 276 kg N ha-1), integrated fertilizer (46 kg N ha-1 + 2/5 ton ha-1 FYM, 92 kg N ha-1 + 5 ton ha-1 FYM and 138 kg N ha-1 +7/5 ton ha-1 FYM ) and organic Farm Yard Manure (5, 10 and 15 ton ha-1 FYM ) along with three levels of irrigation (optimum irrigation (control), water stress 75% optimum irrigation and water stress 50% optimum irrigation) were used as treatments. The results showed maximum seed yield was produced with 92 kg N ha-1 + 5 ton ha-1 FYM and average of seed yield was 7976 kg ha-1. Maximum corn seed yield resulted when optimum irrigation water was applied and average seed yield was 7041 kg ha-1. When water stress was imposed in 50% and 75% of optimum irrigation, seed yield was decreased by 33 and 12%, respectively. The best seed yield was obtained with interaction of 5 ton ha-1 FYM and optimum irrigation. Also, maximum water use efficiency was obtained in using 50% of optimum irrigation. Maximum water use efficiency was obtained with interaction of 92 kg N ha-1 + 5 ton ha-1 FYM and imposition of water stress in 50% optimum irrigation. Results showed that adequate nitrogen fertilizer slightly increased corn seed yield under stress, and integrated (nitrogen and manure) fertilizer increased corn seed yield under stress. But seed yield greatly increased with optimum irrigation. Integrated fertilizer application increased seed yield even with severe moisture stress. Application of integrated chemical fertilizers and manure produced better seed yield and also decreased the amount of chemical fertilizers and improved soil physical and chemical characteristics.
S. A. Kazemeini, H. Ghadiri, N. Karimian, A. A. Kamgar Haghighi, M. Kheradnam,
Volume 12, Issue 45 (10-2008)
Abstract
In order to evaluate the interaction effects of nitrogen and organic matter on growth and yield of dryland wheat, an experiment was conducted at the research station of the College of Agriculture, Shiraz University at Bajgah in 2005 and 2006. The experimental design was split plot in which three levels of nitrogen (0, 40, and 80 kg N ha -1) were main factors and additive organic matters including liquorice root residue at 15 and 30 Mg ha -1, municipal waste compost at 10 and 20 Mg ha -1, and wheat residues at 750 and 1500 kg ha -1 (all rates equivalent to 50 and 100%) were sub factors. A check treatment (no additive materials) was also included in the experiment. Results indicated that with increasing nitrogen level from zero to 40 and 40 to 80 kg ha-1, wheat yield increased significantly. Among yield components, number of seeds per spike increased significantly with zero to 40 and 40 to 80 kg nitrogen ha-1, but number of spikes m-2 increased significantly only when nitrogen level was increased from zero to 80 kg ha-1. Compared to check (no additive materials), maximum wheat grain yield (32%) was obtained from 100% compost application. Results of nitrogen and organic matters interaction effects indicated that 100% compost application and increasing nitrogen level from 40 to 80 kg ha -1 had no significant effect on dryland wheat yield. This showed the positive impact of compost application on the reduction of nitrogen fertilizer. Thus, it appears that 50% of the required nitrogen fertilizer could be replaced by compost. Applying organic matter increased soil water in both years, however, among organic matters, compost had a more pronounced effect on increasing soil water.
M. Bayat, B. Rabiei, M. Rabiee, A. Moumeni,
Volume 12, Issue 45 (10-2008)
Abstract
To study relationship between grain yield and important agronomic traits of rapeseed in paddy fields as second culture, fourteen varieties of spring rapeseed were grown in a randomized complete block design of experiment with three replications at Rice Research Institute of Iran, Rasht, during 2005-2006. Analysis of variance showed that there were significant differences between varieties for most of traits. Broad sense heritability ranged from 0.29 for pod length to 0.99 for days to maturity. Phenotypic and genotypic coefficients of variation for days to maturity and the number of pods in secondary branches were the lowest and highest, respectively. Moreover, genetic advance with 5% of selection intensity varied from 3.68% (0.25 cm) for pod length in main branch to 31.48% (915.58 Kg.ha-1) for grain yield. Results from genotypic correlation coefficients demonstrated that there were positive significant correlations between grain yield and the number of secondary branches, the number of pod in main and secondary branches, pod length in secondary branches, pod diameter in main and secondary branches, 1000-grain weight and oil percentage, and negative significant correlations between grain yield and days to 90% of flowering and days to maturity. Path analysis on genotypic correlations for grain yield as a dependent variable and the other traits as independent variables showed that the 1000-grain weight and the number of pods in secondary branches had the highest direct effects and days to 90% of flowering had low and negative direct effect on grain yield. Therefore, indirect selection for increasing 1000-grain weight and the number of pods in secondary branches are recommended for improving grain yield in rapeseed as second culture in paddy fields.
M. R. Tadayon,
Volume 12, Issue 45 (10-2008)
Abstract
In order to investigate the effect of sugar plant effluent on shoot solute percentage, yield components and grain yield of two wheat cultivars, a two year field experiment was conducted on a farm near Eghlid sugar plant during 2004-2005. Treatments consisted of two wheat cultivars (Alamot and Zarin) and two irrigated treatment: irrigation with effluent and irrigation with spring water (control). The statistical design was a completely randomized factorial with three replications. The results showed that under effluent treatment, nitrogen, phosphorus and calcium percentage increased in shoot, and Fe, Mn, Zn, Cu and B concentration decreased. However, effluent treatment had not any significant effect on K, Mg and S concentration. The results showed that N percentages in Alamot and Zarin cultivar under control treatment were 2.41 and 2.54% and under effluent treatment were 3.28 and 3.41%, respectively. P percentages under control treatment were 0.42 and 0.47% and under effluent treatment were 0.46 and 0.51%, respectively. Ca percentages under control treatment were 0.29 and 0.32% and under effluent treatment were 0.46 and 0.51%, respectively. In both years, the lowest number of tiller, number of spike, number of kernel per spike, thousand kernel weight, grain yield and harvest index were obtained from effluent treatment in the two wheat cultivars whereas this reduction was higher in Alamot than Zarin cultivar. In Alvand and Zarin cultivars, the lowest number of tiller per plant with 2.33 and 2.50, number of spike per plant with 1.83 and 1.92, number of kernel per spike with 31.67 and 32.50, grain yield with 5233 and 5532 kg ha-1 and harvest index with 32.03 and 33.53% and water productivity with 0.72 and 0.75 kg m-3 were respectively obtained from effluent treatment compared to control. Thus, the results showed that using sugar plant effluent could decrease grain wheat quality and wheat grain yield.
F. Heidari, S. Zehtab-Salmasi, A. Javanshir, H. Aliari, M. R. Dadpour,
Volume 12, Issue 45 (10-2008)
Abstract
In order to examine the effects of plant density on the morohological traits, yield and essential oil of peppermint, an experiment was conduced in Agricultural College of Tabriz University during 2005 and 2006. The treatments included four plant density levels ( 8,12 ,16,20 plants.m-2) with three replications. The treatments were based on a split plot design in time and result analysis of compound variance was done during two years. The two years’ results of the compound variance showed that the plant density affected the fresh yield, dry yield, the bush essential oil percentage and the essential oil yield, but it had no effect on the bush height and the leaf’s essential oil percentage. In the second year, the maximum fresh yield, dry yield, bush height, the bush essential oil percentage, and the essential oil yield were obtained. In the second year, the maximum essential oil yield in the density of 20 plant/m2 was 21.15 li.ha-1.
F. Amini, G. Saeidi, A. Arzani,
Volume 12, Issue 45 (10-2008)
Abstract
In order to investigate the relationship among seed yield and its components in safflower, path and factor analysis were conducted using the agronomic and morphological traits of 32 genotypes. Genotypes were evaluated on the Research Farm of Isfahan University of Technology, using a randomized complete block design with three replications. The correlation coefficients showed that number of seeds per capitula and number of capitula per plant had the highest positive correlation with both seed yield and seed yield per plant. The results of regression analysis showed that number of capitula per plant explained 43.6%, and along with seeds per capitula and plant height 60% of the phenotypic variations for seed yield. The regression analysis for seed yield per plant also revealed that seeds per capitula, capitula per plant and seed weight in order had more contributions to the variation of seed yield per plant and explained 81.2% of its variation. Path analysis showed that capitula per plant had the most direct positive effect on both seed yield and seed yield per plant however, this effect was decreased by the indirect and negative effect of seed weight. Results of factor analysis recognized 3 main factors which explained 81.81 % of total variation of the data. These factors were named the seed yield and its components, phenological traits and branching. In general, it can be concluded that seeds per capitula, capitula per plant and seed weight in order contributed more to the seed yield of safflower genotypes. In conclusion, these yield components can be used as selection criteria in breeding programs.
M. Gholamhoseini, M. Aghaalikhani, M.j. Malakouti,
Volume 12, Issue 45 (10-2008)
Abstract
In order to study the effect of various amounts of nitrogen (N) and Iranian natural zeolite on the quantitative and qualitative forage yield of winter canola (Brassica napus L.) in light soil, a field experiment was conducted on research farm of Tarbiat Modares University, Tehran, during 2006-2007. Treatments were arranged in the form of RCBD with 3 replications. The experimental treatments were based on factorial various levels of zeolite (0, 3, 6 and 9 t.ha-1) and nitrogen (90, 180 and 270 kg ha-1) in urea form. Seeds of canola (Brassica napus L. cv. Okapi) were sown on October 2, and fresh forage was harvested at the time of silique formation (170 DAP). Results showed that the effect of N and zeolite on forage quantitative attributes including biomass, leaf and stem dry weight and leaf area index were statistically significant. In addition, forage qualitative traits including crude protein percentage and calcium percentage in plant mass were significantly affected by N and zeolite. Increasing application of N fertilizer caused increase in N leaching, and with increasing zeolite application, N leaching reduced. The interaction of two factors for all parameters was not significant. The most increasing effects on forage yield and quality were gained using 270 kg N ha-1 in combination with 9 t. Zeolite ha-1. More detailed studies are strongly recommended to investigate the effects of integrated application of chemical fertilizer and natural zeolite.
S. M. Mansouri, M. Mobli, R. Ebadi, A. Rezai,
Volume 12, Issue 45 (10-2008)
Abstract
Because of many small florets and protandry, cross pollination in onion which is a biennial plant, by using polycross method for breeding is suitable and easy. To produce polycross seed, bulbs of 9 self onion genotypes were planted in the shape of equilibrium lattice design for 9 treatments with 10 replications on May 2002. To study some agronomical characteristicss, the polycross seeds produced from free pollination and original self-fed seeds (totally 18 genotypes) were planted in plots as a randomized block design with four replications. Samples were taken from each plot and different characteristics were measured. Results showed that polycross generally increased plant fresh and dry weight, plant height, percentage of off type bulbs and yield, with no effect on bulbing ratio and time to ripening. Although polycross increased most agronomical characteristics and yield in Kashan, Azarshahr and Kazeroon genotypes, in some genotypes little increase or even negative effects resulted due to interaction between genotype and polycross. With more assessment of polycross genotypes, good characteristics will be fixed and seeds with higher qualities will be produced.