فصلنامه زراعت و اصلاح نباتات
سال یازدهم شماره 3 (پاییز 1394)

Dry matter accumulation and cytokinin (zeatin and zeatin riboside) levels of grains in various positions within the wheat (Triticum aestivum L. Var. Pishtaz) spike and spikelet were investigated during the grain filling duration. This experiment was conducted in greenhouse of Islamic Azad University¡ Saveh Branch¡ in 2010-11 farming year. Main shoot of wheat were partitioned into proximal¡ middle and distal regions and further into bold (basal) and small (apical) grains. Ten labeled spikes were sampled every 4 days from 3 days after anthesis (DAA) to 23 DAA¡ and every 7 days from 23 DAA to maturity. Results indicate that the cytokinin level increased rapidly from about 7 until 15 days after anthesis and then decreased depending upon the position of grains in spike and spikelet. The differences in cytokinin levels¡ both among spikelets in different regions of the spike and also among grains within a spikelet¡ were positively correlated with the differences in dry matter accumulation. Higher zeatin and zeatin riboside contents in the grains at the early grain filling stage¡ may promote the division of endosperm cells¡ thus constitute a powerful sink¡ and enhance assimilate migration and its accumulation in the developing grains. The results suggest that cytokinins in the grains during the early phase of grain development play an important role in regulating grain filling pattern and consequently influence grain filling percentage.

In order to determine appropriate planting spaces¡ and nitrogen fertilizer levels on rice promising line 8608¡ a field experiment was carried out at the Rice Research Institute of Iran– Deputy of Mazandaran (Amol) during 2008 and 2009. The experiment was laid out as factorial based on a Randomized Complete Block Design with 3 replications. There were three levels for planting spaces (16×30¡ 20 20 and 25×25 cm) and nitrogen fertilizer had four levels(0¡ 92¡ 115 and 138 kg N ha-1¡ respectively). Some agronomical traits such as length of panicle¡ number of filled and unfilled grains¡ totalnumber of grains per panicle¡ 1000 grains weight and economic yield were measured.Results showed that Planting spaces and nitrogen levels had significant effects on grain yield and the highest grain yield was obtained from the Planting spaces of20×20 cm and application of 115 kg N ha-1.

In order to study the effect of different densities on the quantitative and qualitative characters of the two cultivars of alfalfa in condition of Alley Cropping system an experiment was done in the experimental field of Agriculture College¡ Karaj unit in the years 1388-1389. It was done in the form of split factorial in randomized complete block designin two rep.The treatment were: two cultivars (Hamedani alfalfa and ghare alfalfa)¡ and five density(5¡10¡15¡20¡25 kg/ha)¡ and three harvest¡ in thisexperiment cultivars were main plot¡ density and crop were sub plot. The measured character included the percentage of Crude protein of leaf and steam¡leaf and steam Fiber¡ Fresh weight¡ Dry weight and total yield protein. The results corresponding to the analysis of variance showed that the interaction of density had a significant effect on crud protein of steam at= 1% and had a significant effect on steam fiber at p=5% .The result of mean contrast of stages effect showed that the stages had a significant effect on other character at p=1%. The interaction of density* stage had a significant effect on leaf total fiber at p=5%.The result corresponding to the analysis of variance showed that the interaction of density on crude protein of steam in density levels 4 and 5 were about 12/97¡ 12/81had highest means and levels 1and 3 had the least percentage. Total fiber in steam was oposite¡level 1 had the least. Also stage three had highest percentage of crud protein of leaf (32/06) and steam about (14/28).The stage two had the least percentage of crud protein leaf and steam (25/41)¡(12/6). Highest fresh weight was in stage three(4782/8 kg/ha) and stage one had the least fresh weight and dry weight (2270/6 kg/ha)¡(668/41). The highest dry weight was in stage two it was about (1509/88 kg/ha). Moreover the highest and lowest proteinyield corresponding to the second stage(293/35) and first stage (140/56). Stage effect showed first stage had highest Fiberpercentage of leaf (27/64) and steam (41/18).

A field experiment was conducted aiming to determine the possibility of improving the lentil performance as co-inoculated with Vesicular Arbuscular Mycorrhiza (VAM) fungi and Azospirillum under rain-fed conditions. A tri-factorial experiment was organized on the basis of Randomized Complete Block Design with four replicates¡ in which factor M was the Mycorrhizal inoculums in three levels (not use¡ use Glomus intraradices and use Glomus mosseae)¡ Factor A was Azospirillum in 2 levels (not use and use Azospirillum brasilense) and factor L as the lentil cultivar with two levels (Mashhadi and Naz cultivars). The results showed that the effect of Mycorrhiza on traits of root dry weight and Mycorrhizal root dry weight was significant at the 1% probability level.Highest value for root dry weight and Mycorrhizal root dry weightwas recorded in plants inoculated with Glomus mosseae.Also¡ Azospirillum and Lentil cultivars were not significanteffect on all traits.The results showed that the interaction between Azospirillum and Lentil cultivars on seed yield at the 5% probability level was significant.

Maximizing of nitrogen use efficiency has an important rule in sustainable agricultural development. This experiment wasconducted in order to investigate the reduction effect of nitrogen and instead useing of Azotobacter inoculants and Mushroom compost on potato yield in 1392.The experiment performed split factorial based on complete randomized design in three replication in the farm of Sheykhlar located in Razan Hamedan.Main factor was nitrogen from the source of urea in three levels including 100% nitrogen (as suggested by soil and water research institute) ¡ 75% nitrogen suggested¡ 50% nitrogen suggested . Second factor was mushroom compost and Azotobacter levels as factorial.Compost were used in two levels control and 11 ton/ha. Azotobacter (Azotobacter chroococcum) were used in two levels control and application of bacteria as spraying on tubers. Results of nitrogen application showed significant effect on tuber number per unit area¡tuber yield¡ average weight of tubers per plant in 1% level of probability. Results of using compost also showed significant effect on tuber number per unit area¡ average weight of tubers per plant in 1% level of probability. Azotobacter showed significant effect on total number of tubers per unit of area ¡ tuber yield and average weight of tubers per plant in 5% level of probability.

In order to determine the effects of different tillage methods on apparent density of soil and yield of forage corn¡ experiments were carried out on a land in Miandoab town from west Azarbaijan. The treatments include: moldboard plow and double disk¡ chisel plow and double disk¡ disk plow and double disk and cultivator with one disk. The results showed that different tillage methods have significant effects on apparent density during different measurement period (1 day¡ 15 days¡ and 30 days after tillage). Maximum apparent density related to cultivator treatment during 30 days after tillage with 2.18 g/cm3 and minimum apparent density related to disk plow treatment during one day with 1.69 g/cm3. By increasing time of measurement after tillage¡ the ration of apparent density increased 23%. In deeps of (0-5)¡ (5-10) and (10-15) cm of soil¡ variation of apparent density of soil was not significant. Effects of tillage methods on yield of forage corn by one percent probability were significant and maximum performance related to disk plow with 61.5 tons per hectare.

The present study was performed with use of Esfehan variety in the research field of Arak Azad University in the 2009 agricultural years. This experiment was performed in factorial split plot in randomize complete block design in 4 Replication and 48 plot. Treatment included two planting date 10 may and 10 July(delayed plant) and different level of N include (46¡92¡138)kg per hectare and two plant density included 400.000 and 800.000 plant per hectare that 800.000 plant per hectare executed in double row planting. the result of this study showed that the highest yield of the 821.17 oil per hectare was related to the treatment of date of planting 10 may with 92 kg N and plant density of 800.000 per hectare. Also¡ the lowest yield of 444.42 kg/h was related to the date of planting 10 may with 92 kg N and 400.000 plant density per hectare¡ Therefore¡ plant density has very influence on the yield of safflower. So¡ according to the result¡ 800.000 plant density in per hectare has direct effect on the yield of safflower rather than 400.000 plant density.

Beans as an important source of food are increasingly under attention nowadays. Genotypes as well as yield components can be affected by agricultural managements. This experiment was conducted as split plot based on randomized complete design with three replication in Challus city- Mazandaran Province. Main factor was distance between rows(25¡45¡65 Cm) and sub factor was distance of plants on rows(10¡15¡20 Cm). Results of distance between rows¡ distance of plants on rows and interactions showed significant differences for most of the measured traits. The best and highest yield obtained from 45 Cm distance between rows and 15 Cm distance between plants on the rows.

Biologic fertilizers actually are complex of some micro organisms that mobilize main nutrients from unavailable form to available form and can improve root system and seed germination and are one of main sources of nutrients providing in sustainable agriculture. To study effects of biologic fertilizers on growth of dill (Anethum graveolens) an experiment was curried out in Looieen plain (Saveh suburb).Investigation conducted on the basis of complete randomized blocks design with four treatments and three replications.The treatments were as fallow: 1- Nitroxin application (Azotobacter and Azospirillum bacteria). 2- Barvar2 application (pseudomonas flurescence) as phosphorus solubilizing bactria. 3- Application of mixture of above two biologic fertilizers. 4-control treatment (without any biologic fertilizer application). Results showed utilization of biologic fertilizers significantly increased seed yield¡ biologic yield¡ bush height¡ umberella flowering arrangement number in bashes¡ seed number in any umberella¡ seed number in bashes and one thousand seed weight.Nitroxin Barvar 2 had most effects on above parameters and nitroxin also had promising results. Most and least seed yield obtained in first treatment and control (16.31 and 9.8 gr) respectively. It was concluded utilization of biologic fertilizers improves growth and growth characteristics of dill and can substitute chemicals without hazards to environment.

This research was conducted to evaluate the effect of drought stress and foliar application of phosphorus on yield and yield component of wheat in experimental field of Islamic Azad University Karaj Branch in 1387-89. The experiment performed factorial split plot based on complete randomized block design with four replication. Treatments were included: four levels of phosphor foliar application 0¡2¡4¡6 kg/ha from the source of KH2PO4)¡ three levels of drought stress (40% ¡ 60% and 75% available moisture reduction) and two growth stage based on Fix method(stage 7)(second node appearance) and stage 10/1(appearance of spike). Yield and yield components were measured at the harvest time. Results showed significant difference among irrigation treatments. Minimum seed yield obtained in 75% available moisture reduction and maximum yield obtained in 40% available moisture reduction . Results also showed that foliar application of phosphor increased significantly seed yield ¡ biological yield¡ peduncle length¡ number of spike in unit area¡ number of grain per spike and plant height. Maximum grain yield obtained from six kg/ha phosphor treatment and minimum grain yield obtained in control treatment. Triple interaction showed significant effect on seed yield. Irrigation in 40% available moisture reduction treatment in the appearance time of second node and appearance of spike time showed maximum yield with application of six kg/ha phosphor foliar application. Irrigation in deficit irrigation treatment (60% available moisture reduction) and in spike appearance time showed maximum yield with six kg/ha phosphor foliar application. In deficit irrigation treatment (75% available moisture reduction)¡ foliar application of phosphor showed no yield increase and all foliar application phosphor treatment arranged in a same order in Duncans test.