نشریه پژوهش های کاربردی زراعی
پیاپی 85 (زمستان 1388)

The effect of N and P fertilizers application base on soil analysis were studied during 1999 and 2000 growing season in Fars and Esfahan Provinces of Iran. For 1999 and 2000 growing seasons in Esfahan and Fars Province 56 and 2000 growing season 36 and 56 and 38 sugar beet farms were randomly selected، respectively. In each farm، soil and water samples were selected and analyzed for routine soil fertility test. Each farm divided into two parts. In one part، all fertilizers were recommended based on the results of soil analysis (RST) and in the other part based on the farmers traditional method (FT)، while all cultural practices were identical for both sections. During the growing season all farms were visited and cultural recommendation for enhancing sugarbeet values were given. At the end of growing seasons، sugar beet crops were harvested and their yield and quality were determined for each section. The results were analyzed using pair wise t test at 5 and 1 percent probability levels. The results showed that effect of RST and FT treatments on both yield and quality of sugar beet were significantly greater for RST than FT in Fars and ESfahan Provinces. For 1999 growing season، the root yields for RST were 34. 69 and 36. 12 t/ha which shows 600 and 900 kg/ha increase compare to FT in Fras and Esfahan Provinces، respectively. For 2000 growing season، the root yields in RST were 33. 96 and 32. 1 t/ha which were 1200 and 800 kg/ha higher than FT treatment. In the year 2000، sugar content of RST treatment in Fars was 16. 01% which in comparison to FT treatment it was increased significantly (P<0. 05). In Fars Province during 2000، sugar yield of FT treatment was 4. 87 t/ha which due to RST it was increased by 440 kg/ha. In Esfahan Province، in both years RST treatment increased the sugar yield. In the year 2000، RST treatment increased white sugar yield، thus fertilizer recommendation based on the results of soil analysis in the sugar beet farms may enhance the technical quality of sugar beet.

Six upland cotton varieties called Varamin، Mutagenesis، 818-312، Bul-539، B-557 and Chirpan-539 were planted in deputy office of cotton research institute (Varamin) in 2003. Diallel method of crosses including parents without reciprocals was applied to produce F1 populations. Parents and progenies were planted using 3 replications under randomized complete block design (RCBD) in 2004 and 17 phonological properties were evaluated. Results of diallel analysis showed data coincidence with dominant additive model proposed by Hayman and Griffing. Partial dominance effects of genes influenced on controlling Date of first flower، total bloom، plant height، date of first open boll، boll maturation period، earliness، maturity index and product rate index. In contrast، overdominance effects of genes influenced on controlling horizontal flowering interval، vertical flowering interval، boll weight، number of monopodia، yield، bloom index and mean maturity data. Heritability in narrow sense ranged from 0. 58 to 0. 59 for plant height، 0. 66 to 0. 67 for earliness، 0. 53 to. 063 for production rate index، 0. 0 to 0. 19 for yield and was zero for mean maturity data.

In order to find out the effect of different levels of zinc sulfate and irrigation intervals on morphological characteristic and also on yield and yield components of sunflower. Plot in a completely randomized blocks including three replications different levels of irrigation namely 10، 20 and 30 days as first factor and zinc sulfate levels of 0، 20 and 40 kg per hectare the second factor. Irrigation was in main plot and zinc sulfate in subplots. Measurements included; leaf area index at start of blooming، final leaf area index، leaf weight of stem، weight of over ground parts، special density of leaf، ratio of leaf weight to stem of plant، diameter of stalk، number of days till reproductive stage، number of days till full bloom، number of days till end of pollination، time between blooming and complete physiological ripening of seeds، length of reproductive period، flower diameter، number of seeds per flower، weight of 1000 seeds، dry weight of seed per flower، ratio of weight of seed per flower to weight of flower، percent of unfertilized seeds، seed yield and the yield index. Statistical analysis was preformed by analysis of variance and Duncan method. The results showed that by increasing the interval of irrigation decreases the yield and on the most of under research components had bad effects; zinc sulfate deficiency has effect on most of characters there was no significant difference between 20 and 40 kg zinc sulfate per hectare. The interaction between irrigation and zinc sulfate consumption indicates that between 10 and 20 days irrigation yield is differed significantly. Other measured characters also got better in the presence of zinc. Even the application of zinc at 20 days irrigation interval resulted the yield equal to 10 days interval. In 30 days irrigation period zinc sulfate has no effect on yield and some other characters; but caused the number of seeds per flower and increase of vegetative growth of sunflower. The height yield was detected in 10 days irrigation interval and 40 kg of zinc sulfate application per hectare as 3258 kg per hectare. In irrigation interval of 20 days and use of 40 kg zinc sulfate caused the yield from 2433 kg (no zinc sulfate) to increase 2881 kg per hectare.

In order to evaluation of drought resistance، 24 barley lines in drought stress and non-stress conditions planted in RCBD experiment with 3 replications. Along whole growing period all morphophysiological traits also recorded. The results of statistical analysis showed that: Stress Tolerance Index (STI) and Geometric Mean Productivity (GMP) are the best drought indices. Based on these indices lines Yesevi-93 (Abidar)، CWb22-6-13/ICB-102893، ICB-111877 identified as drought tolerant lines with high yield. On the other hand two-row barley is more drought tolerance than six-row barley. In evaluation of morphophysiological traits in drought stress conditions، STI and GMP indices have positive correlation with heading period length، plant height، awn length، harvest index، 1000-grain weight and grain-No per spike and negative correlation with grain filling period length.

In order to study the effects of delay planting date and seeding rate on seed yield of two wheat genotypes، Zarrin and C-79-16 were planted dates (7 October، 17 October، 27 October، 6 Novamber، 16 Novamber، 26 Novamber، 5 December and 15 December) with three seeding rate (450، 550 and 650 seed/m2). Experimental design was a Strip Split plot layout based on Randomized Compelet Block Design with three replications in two years (2003 - 2005) at Agriculture Research Station of Miandoab in West Azarbayjan. Interaction effects planting date × seeding rate and planting date × genotypes × years were significant on seed yield (p < 0. 05). Grain yield was decreased from 6071 to 3753 kg/ha-1 as delay planting date from 7 October to 15 December with 450 seed/m2. But higher seeding rate (650 seed/m2) yielding more grain، especially in the last four planting dates. Regression analysis showed that delay planting date for each day of delay 7 October on with seeding rate of 450 seed/m2 decreased the grain yield by 37 kg/ha in a day. Result of this research showed that when planting date is delayed، seeding rate should be applied for increasing seed yield.

On the basis of the results gained from the test of the evaluation of quantitative and qualitative producing potential of IAA، in this research 31 bacterial isolates were selected and their potential was studied in vitro conditions. In vitro test results on wheat showed that bacterial treatment and also the Ag and Trp treatments had significant effect on measured parameters. The comparison of the mean shows that between the rhizobial treatment effects is a significant difference on the measured parameters too. Also the mean comparison of Ag and Trp Treatments shows that usage of both Ag and Trp treatments together causes a significant increase on measured parameters in comparison with using Ag and Trp alone and also in comparison with the blank. So، the most important assimilation mechanism by rhizobial strains is production of Indole phytohormones (IAA) which results the better root growth، so increase of water and micronutrient uptake by the plant and increase of the plant growth.

This research was conducted in order to have genetic evaluation of some important agronomic traits as related to seed yield، using 20 soybean varieties in randomized complete block design with three replicates at Agricultural Experiment station، college of Agriculture، karaj.، Iran. A total 20 traits related to vegetative and reproductive growth and yield component were analysied. Analysis of variance showed that there were significant differences among varieties in terms of traits under study، indicating the existence of genetic variation among varieties. Duration of seed filling and pod length had highest and yield had the lowest broad sense. Among the desired traits، 100-seed weight، number of seed / plant and number of seeds/pod، all of which are considered yield component، had the highest correlantion with plant yield. Using multiple linear regression model for 20 traits under study، showed 93% of total variation in yield plants، were attributed to three traits: Namely 100 seed weight، number seed/plant and seed width. Result of path analysis showed the highest and the lowest direct effect، being positive، were related to number of seed/plant and seed width، respectively. Results of factor analysis showed the important factor، called yield component. This factor explained 17/3% of total variation in data.

In order to evaluate nitrogen fixation and nodulation ratio in bean (Phaseolus vulgaris L.) Iranian cultivars with different strains of Rhizobium leguminosarum biovar phaseoli with Plant Growth Promoting Bacteria to determine the best bacteria×cultivar’s combination، a spilt plot experiment in randomized complete block design was conducted in the field at Shahrekord، Iran in 2006 and 2007. The factors were six bacterial strains Rb-133، Rb-133×Azospirillum، Rb-133×Pseudomonas، Rb-136، Rb-136×Azospirillum، Rb-136×Pseudomonas and non-inoculated controls including application of nitrogen fertilizer treatment (100 kg N ha-1) and without application of nitrogen fertilizer in main plots. Three bean cultivars Sayad، Akhtar and Goli were assigned as factor B to subplots. The results revealed that there were significant differences among levels of factor A in shoot nitrogen content، nitrogen fixation، number nod، dry weight and fresh weight of nod at early flowering (45-50 days after emergence). Treatment of inoculated seeds with strain bacteria×Pseudomonas and non-inoculated control (without N–fertilizer application) demonstrated the highest and lowest nitrogen fixation and nodulation، respectively. The results showed that all treatments of bacteria are capable of nodulation; however، strains Rb-133 gave highest nodule dry weight، N total (shoot) and percent of fixed N2.

Precision farming attempts to improve cropping efficiency by correct planning، a necessary first step in this process is the search for techniques able to identify functional relationships between measure soil and site characteristics and crop yield. Agro ecological zoning of the region was obtained by the use of climate، soil and topographical data base and determined homogen zone for this study. Each crop yield potential was calculated and finally the crops yield were determined for each zone. A variety of supervised feedforward neural network techniques، including several variations of backpropagation were selected for investigation about barley maze and wheat yield prediction. the performance of all artificial neural networks was assessed based on calculating the mean absolute error (MAE)، the root mean square error (RMSE) and the coefficient of determination (R2) of linear regression line between the predicted values from either the ANN model and the desired output was also used as a measure of performance. Input layer include soil chemical and soil physical properties as well as climatical and topography factors. In this research use of multilayer feedforward neural network with backpropagation algorithm. Artificial neural network models with two hidden layer have good accuracy between predicted and observed yield in training and validation. ANN performance show significant preciseness from land condition for predicts yield.

In order to evaluation the effects of terminal drought stress and rate of nitrogen application on yield and yield components of canola (Brassica napus L. cultivar Hayola 401) an experiment was conducted in a split plot at base of randomized complete block design (RCBD) with four replications in experimental field of agricultural and natural resource of Ramin in 2004-2005. Drought stress at three levels without stress (S1)، moderate (S2) and severe (S3) water stress where irrigation was done after depletion of 25، 50 and 75 % field capacity (FC) respectively as main plots and different levels of nitrogen application at 4 level: 90، 140، 190 and 240 kg nitrogen. ha-1 were consider as sub plots. Drought stress treatments were implement from flowering stage and continued after maturity. The results showed that the effects of different levels of drought stress and nitrogen application on grain and oil yield were significant. The highest grain yield (3622 Kg. ha-1) was obtained at no stress condition. Moderate and severe drought stress reduced grain yield by 14 and 30. 8 % compared to no stress condition، respectively because of significant decrease in number of silique. m-2 and 1000-seed weight. With increasing of nitrogen application the number of branches، silique. m-2 and 1000-seed weight and consequently seed yield was increased significantly. Seed oil content adverse to seed protein content with increasing the severity of drought stress was decreased. Increase in nitrogen led to increase in protein content، but oil content was decreased. Highest seed and oil yield (4060. 5 and 1850. 8 kg. ha-1، respectively) were obtained in 190 kg nitrogen. ha-1 at no stress condition (S1N3).