فصلنامه پژوهشهای زراعی در حاشیه کویر
سال نهم شماره 4 (زمستان 1391)

The physiological impact of source restriction on corn (hybrid SC704) yield formation due to water deficit stress was studied in Varamin during 2007-2008 and 2008-2009 growing seasons. The experiment was carried out in a complete randomized block design with split plot arrangement. In under stress plots, two short periods of water-holding were applied at V8 and tasseling growth stages. Defoliation treatments consisted of: control, cutting 1/3 of leaves at V8, cutting 2/3 of leaves at V8, and cutting 1/3 of leaves at tasseling and cutting 2/3 of leaves at teaseling. The grain yield of 8.9 t .ha-1 was attained by moderate irrigation which was a results of 16.4% and 27.3% greater biomass and harvest index compared to the water stress conditions. The water stress reduced the available assimilates during grain filling which resulted in reduction of grains per ear from 598 to 455, while increased the 1000-grains weight from 105 to 168 g. Positive and significant correlation between the grain yield and number of grains per ear indicated that this yield component is more important than individual grain weight for yield formation. The results showed that cutting 1/3 of leaves at tasseling not only did not decrease the dry matter accumulation but also increased the grain yield by more dry matter partitioning to grain filling process. Under water stress, late but scanty defoliation increased the water content of remaining leaves and their photosynthesis which resulted in higher grain yield.

To determinate the best foreign safflower cultivars with high seed yield and oil content, an experiment was conducted on eight foreign cultivars Hartman, kino 76, Sonora 92,Bacun-92, Saff-891, monte-81 ,CW86 and Sidwill together with two Iranian cultivars Goldasht and S-55 in Bojnourd during 2009-2010 cropping season using a randomized complete block design with four replications. Some agronomic traits such as head number per plant, seed per head, plant height, days to flowering and days to maturity were recorded during the growth period and 1000 seeds weight, seed yield and yield and oil yield were measured traits. The highest seed yield (1056 kgha-1) and oil yield (340 kgha-1) were produced by Goldasht cultivar. Significant and positive correlations were found between seed yield and seed oil, number of secondary branches and plant height. Cluster analysis based on these traits, grouped the Iranian and foreign cultivar in separates clusters.

In order to study the effects of free living nitrogen fixing bacteria and nitrogen chemical fertilizer on yield components of corn cultivar SC 647, a factorial experiment based on randomized complete block design with four replication was conducted at Varamin, Iran in 2010. The factors in this study included Azospirillum, Azotobacter and nitrogen chemical fertilizer. Azospirillum consisted of two levels (non application-application), Azotobacter consisted of two levels (non application-application) and nitrogen chemical fertilizer consisted of two levels (application of net nitrogen chemical fertilizer at the rate of 200 Kg ha-1 and application half of net nitrogen chemical fertilizer at the rate of 100 Kg ha-1. Results revealed that with application free-living nitrogen fixing bacteria with half rate nitrogen chemical fertilizer increased all of traits except seed number in row.

Water deficit stress is a common a biotic stress that seriously affects crop production in more parts of the world. Thus, in order to study the effects of water deficit stress and zinc foliar application and sulfur application on quantitative and qualitative characteristics of sunflower, an experiment was conducted at Varamin, Iran during 2014 growing season. The experimental design was laid out in a randomized complete block with a split plots arrangement of treatments in three replications. Main plots included three different levels of irrigation (complete irrigation, irrigation withholding at flowering stage and irrigation withholding at seed filling period stage) and sub plots were included four different zinc and sulfur application (untreated zinc and ]sulfur application, zinc foliar application, sulfur application and both zinc foliar application and sulfur application) The results showed that irrigation withholding conditions in different growth stages significantly decreased seed yield, biological yield, harvest index, oil percentage and oil yield and total chlorophyll content, Relative Water Content but by contrast increased superoxide dismutase activity in leaves. Both zinc foliar application and sulfur application treatment had positive effect on all attributes in this experiment. In general, the results of the present study indicate that usage of zinc foliar application reduces the harmful effects of water deficit stress and increases resistance to drought stress in sunflower plant.

The growing problem of urban waste generation is threatening public health, and if not cared, irreversible damages will be made to our environment, To solve this problem, we can then convert municipal waste into compost as organic fertilizer used in agricultural fields. This study was carried out to determine the effects of combined municipal city waste with sulfur-coated urea fertilizer on cotton properties of cultivar Varamin. The experiment design was split plot in form of CRB with sixteen treatments and three replications at agricultural research and natural resources center of Tehran province in Varamin. The treatments included: Compost at four levels (0, 20, 30, and 40 tons per hectare) as main plots and sulfur-coated urea fertilizer with four levels (0, 33%, 66%, and 100% of fertilizer needed) as sub plots. Results showed that the effects of sulfur-coated urea treatments on plant height, reproductive branches and effects of compost treatments on number of nodes and boll number was significant at 5% and 1% level. Data showed that the highest boll number and yield were obtained by use of 40 t/hac Municipal soiled waste compost (MSWC) and the highest plant height, reproductive branches and 100-seed weight were obtained by sulfur-coated urea fertilizer with level of 66% of fertilizer needed. Thus, despite the excellence of some other properties in use of other levels of fertilizer in treatments, because of insignificancy of them, combined use of compost and sulfur-coated urea with rate C40N66 is recommended.

In order to study of Effect of foliar application of vermiwash, bioferment and different methods of plant nutrition on oil percentage in sunflower, this study was carried out in field of Payaam Nour Arak University in Markazi province in 2013. A factorial arrangement of treatment in a randomized complete block design with three replications was used. Nutrition methods [N1: 300 Kg ha-1 Urea (Control), N2: 50% of nutrition by Urea 50% of nutrition by FAM (15 ton ha-1), N3: 50% of nutrition by FAM 50% of nutrition by nitrogen fixation of phaseolus sp), N4: 50% of nutrition by Urea 50% of nutrition by nitrogen fixation of phaseolus sp) and plant bio-stimulants (B1: Foliar with wermiwash, N2: Foliar with enrich wermiwash, N3: Foliar with bioferment, N4: Foliar with effective microorganisms quail egg) were assigned in plots. Each sub plot consisted of 4 rows, 5 m long with 50 cm between rows space and 25 cm between plants on the rows. In this study characteristics such as: plant height, head diameter, wet biomass weight, weight of head, harvest index, number of grain per head and oil content were assessed. Results indicated that the effect of different levels of nutrition methods on the characteristics such as: plant height, head diameter, wet biomass weight, weight of head, and oil content were significant. Effect of plant bio-stimulants treatment on the characteristics such as: head diameter, wet biomass weight, harvest index, number of grain per head and oil content were significant, too. The maximum and minimum of oil content (35.64 and 30.99 %) were obtained with the (50% of nutrition by Urea 50% of nutrition by nitrogen fixation of phaseolus sp) and (50% of nutrition by Urea 50% of nutrition by animal manure) treatments, respectively. In the treatment of biostimulat as the most and least amount of oil content with an average 35.24 and 33.17 %, were spray of vermiwash and (effective microorganism quail Egg), respectively.

In order to investigate the effect of nitrogen and bio-fertilizers on canola, an experiment as split-plot was conducted based on randomized complete block design with four replications In Ismaeil-Abad of Qazvin privince. Nitrogen in 3 levels (non application, application of 75 kg.ha N and 150 kg.ha N) as main plots and bio-fertilizer in 4 levels (non inoculation, azotobacter, Azospirillum and azotobacter ̺Ⲧ⫢陛) Omit as subplots were considered. The results showed that nitrogen and bio-fertilizers treatment had a significant effect on plant height. 150 kg of nitrogen was treated as the highest plant height. and Combined use of biological fertilizers also had the highest plant height . Also usage Azospirillum and Azotobacter increases the seed yield. Investigate the interaction of biological fertilizers on yield and nitrogen treatments showed non application nitrogen fertilizer in the highest yield was obtained using a combination of biological mountains. .But in terms of 150 kg nitrogen per hectare, non inoculation had the highest yield. The intact biological fertilizers and biological fertilizers combined with higher grain yield in the treatments in terms of 75 kg per hectare; therefore, half of the recommended nitrogen application of biological fertilizer is suggested.

This study investigated the effects of macro element nutrient and Fe, B and Zn on Agro ecological characteristics of corn hybrid KSC704 under limited irrigation in Varamin region. Research was conducted in a complete block randomized, experimental design with split-plot arrangement in three replications. The main plots consisted of irrigation methods of normal irrigation (AFI),fixed furrow irrigation (FFI), and conventional furrow irrigation (CFI). Each irrigation method was further divided into five sub-treatments with different fertilizer combinations: (1) P (control) (2) P㟢 (3) P㟢빦 (4) P㟢빦羁 and (5)P㟢빦羁.Results of analysis of variance showed that the interaction effects of fertilizers and irrigation methods on the characteristics of number of spikes per plant , number of rows per spike, number of grains per row, 1000 grains weight, grain yield, total above ground biomass, harvest index, oil percentage, protein percentage, LAI, radiation use efficiency, N concentration and uptake N were significant at the 1% level. Reusult showed that irrigation method of was fixed to one of the two neighboring furrows(FFI),decreased yield, yield components, oil percentage, LAI, radiation use efficiency and N concentration and uptake N. However, application of fertilizer treatments reduced the negative effects of water deficit stress. The results also showed that in water deficit condition protein percentage increased unlike other qualitative characteristics. In order to utilize the water sources efficiently and increase corn production under limited water supply, the use of circular irrigation care along with application of K, Zn, B and Fe fertilizer can be recommended.