نشریه علوم به زراعی گیاهی
سال دهم شماره 1 (بهار و تابستان 1399)

In order to investigate the effect of planting date and harvest time on the morphological traits of forage maize (cv. Karoun 701), an experiment of split plot in randomized complete block design with three replications was conducted in Varamin in year of 2015. Treatments included five planting dates as main factor (9th of April, 21th of May, 18th of June, 30th of June and 15th of July) and two harvesting times as sub-factor (milky stage and dough stage). The result showed that the effect of planting dates had significant at 1% level on the plant height, leaf width, leaf area, cob diameter and fresh yield. But had no significant effect on the number of leaf per plant, leaf length, number of internode per plant and stem diameter and were not affected by planting date. Results of this experiment showed that planting date of 30th of June was superior to other planting dates in terms of morphological traits such as plant height, leaf width, leaf area, cob diameter and fresh yield of plant compared to other planting dates, and the amount of the above traits with early and delay in planting are greatly reduced. In between, harvesting time at milky stage had the highest leaf width and leaf area and harvesting at dough stage had the highest fresh yield of plant. It is recommended to obtain optimum corn yield, sowing operations should be carried out in the first half of July in Varamin region and for harvesting quality forage at milky stage and to obtain greater harvest yield at dough stage.

Abstract   This research carried out in a field factorial experiment based on randomized complete block design with three replications in Rasht at 2016-17 growing season. Experimental factors were including two levels of Pseudomonas fluorescent (seed inoculationand uninoculation) and six levels of phosphate fertilizer from super phosphate triple source (0, 30, 60, 90, 120 and 150 kg/ha). Pseudomonas effect was significant on pod length, number of seed per pod, number of pod per plant, hundred seed weight, dry seed yield, harvest index and phosphorous seed content (P≤ 0.01). Effect of phosphate fertilizer was significant on number of pod per plant, hundred seed weight, dry seed yield, harvest index and phosphorous seed content (P≤ 0.01). Interaction effects of two factors were significant on all of the studied traits except of harvest index (P≤ 0.01). The highest value of phosphorous seed content (355 ppm) was observed in combination treatment of 150 kg P/ha and Pseudomonas inoculation. Seed yield was 3893.3 kg/hain combination of seed inoculation with Pseudomonas and phosphate fertilizer (90 kg/ha), which there was no significant differences with 120 and 150 kg P/ha. This fertilizer combination increased 38 percent seed yield in comparison to 90 kg/ha phosphate fertilizer and uninoculation of Pseudomonas bacteria. Overall, the inoculation with Pseudomonas bacteria and phosphate fertilizer (90 kg/ha) could achieve seed yield potential, reduce the adverse environmental impacts and save the P-fertilizer utilization.

Available water is the main factor limiting crop growth and production in arid areas. In this regard, in order to investigate the effect of silicon application on morphological, physiological and yield characteristics of sunflower under different moisture levels, an experiment was conducted in the crop year 1397-1398 in Gonabad. This study was conducted as a split plot in a randomized complete block design with three replications. The main factor of irrigation with different moisture levels based on water requirement includes four levels (100% water requirement, 80% water requirement, 60% water requirement and 40% water requirement) and the secondary factor of silicon consumption time. There were four levels (no application (control), application in vegetative stage, application in reproductive stage, application in vegetative stage and reproductive stage). The results showed that reducing the moisture level from 100% to 40% of water requirement reduced the quantitative traits studied; So that the lowest seed yield (1730.8 kg / ha) and oil yield (583.41 kg / ha) were obtained in the treatment of moisture level of 40% of water requirement. Also, the application of silicon under low moisture levels based on water requirement improved the effects of reducing moisture levels in all evaluated traits and seed yield. The highest seed yield (7572.96 kg / ha) was obtained in the treatment of 80% water requirement and application of silicon in the vegetative and reproductive stages and the lowest value (1193.54 kg / ha) was obtained in the treatment of 40% water requirement and without the use of silicon. Also, the application of silicon in the vegetative and reproductive stages compared to the non-application treatment (control) increased 2.5, 1.5 and 2.5 times the oil yield at different levels of moisture, including 80, 60 and 40% of water requirement. In general, the results showed that the use of silicon in the vegetative and reproductive stages at a moisture level of 80% of the water requirement compensated for the adverse effects of reducing the moisture level in the studied traits.

In order to investigate the adaptation of native rice genotypes to Mazandaran climatic conditions, an experiment was conducted with 30 rice genotypes in a randomized complete block design with four replications in in two regions of Mazandaran province (Amol Rice Research Institute and Sari University of Agricultural Sciences and Natural Resources) during 2016-2017. The results of combined analysis of variance showed that there was a significant difference between the locations of experiment only in terms of panicle length and number of filled and unfilled grains per panicle, while there was a significant difference among genotypes and genotype × environment interaction for all studied traits. Results of correlation coefficients of the traits showed that panicle length, number of filled grains per panicle and number of fertile tillers per hill had a positive and significant correlation with grain yield. For the 30 genotypes studied, three clusters were found that the third cluster genotypes, including Gardeh and Zire Bandpey with higher grain yield in the two studied regions showed more adaptation to Mazandaran climatic conditions.

This study was done to investigate the response of vegetative traits of sunflower cultivars in the presence of fenugreek as living mulch at Razi University in 2017. The experiment was conducted as split-plot based on randomized complete block. First factor was the sowing fenugreek at four levels (control (without living mulch), 15 days before sowing of sunflower, simultaneous sowing with sunflower, 15 days after sowing of sunflower) and the second factor was three sunflower cultivars (Progress, Farrokh, Lakomka). Results showed that with planting of fenugreek before sunflower, height, stem weight, number of leaves, leaf weight, leaf area index, content of chlorophyll a, b and total of chlorophylls were decreased by 26.4%, 62.1%, 24.8%, 68.5%, 63%, 7.4%, 3.7% and 6.8% compared to control, respectively. The lowest relative water content was also obtained by planting fenugreek before sunflower (65.2% and 52.7% at the 1/3 of primary growth season and flowering stages). The effect of presence mulch under the simultaneous and 15 days after sunflower conditions had no significant effect on growth characteristics of sunflower compared to control condition. Among thecultivars, the highest of grain yield was assigned to Lacomka (3426 kg/ha). However, Progress had the highest height (212 cm), stem weight (523 g/plant), leaf number (25.5 per plant), leaf weight (157.4 g/plant), leaf area index (6.2) and relative water content (77.8% and 70.5% at the 1/3 of of primary growth season and flowering stages). The highest of leaf area ratio (0.013 m2/g) and carotenoid content (2.5 mg) belonged to Farrokh.

Organic fertilizers are valuable sources for improving soil quality and increasing crop yield. In order to evaluate the effect of vermicompost and manure application on morphological traits, yield and essential oil of basil (Ocimum basilicum L.), a field experiment was conducted in a randomized complete block design with eight treatments and three replications in Urmia city in 2019. The experimental treatments included control (T1), vermicompost [5 tons (T2), 10 tons (T3), 15 tons (T4), 25 tons per hectare (T5)], cow manure [10 tons (T6), 15 tons (T7) and 20 tons per hectare (T8)]. According to the results of ANOVA, the effect of the treatments on all studied traits was significant (p≤0.01). Results showed that T5 treatment increased plant height, number of leaves per plant, biological yield, seed yield, essential oil content and essential oil yield in comparison with control 67.81, 60.91, 53.36, 42.86, 109 and 72.95%, respectively. The highest number of lateral branches per plant (15.61) belonged to the T8 treatment, which was not significantly different from the T5. The T4 treatment had the maximum (45.66) flower number per plant among the treatments and this treatment was not significantly different from the T5 treatment. Also, the highest 1000-grain weight (2.72 g) was obtained from T4 treatment, which was in a same statistical group with T5 and T8 treatments. Overall, the results indicated that the application of vermicompost and cow manure had a favorable effect on morphological traits, yield and essential oil content of basil.

Based on the increasing literatures on medicinal plants and their importance in the food and pharmaceutical industries, the present study was designed to study on the medicinal plant Physorrhynchus chamaerapistrum. Silica (Si) is known as a beneficial element for many plant species. In the present study was designed to study on the effect of potassium silicate treatment on some physiological traits of P. chamaerapistrumare. In this order, foliar application of 10 and 20 mM potassium silicate and distilled water (as control plant) was applied on P. chamaerapistrumare in their natural habitat in Behbahan. After one month, the leaves of the plants were harvested to investigate the physiological responses of the plants to the potassium silicate treatment. Based on the results, Silica treatment had not significant effect on the leaf fluorescence indices, while it significantly increased photosynthetic pigments in P. chamaerapistrumare. Silica treatment did not show a significant effect on the efficiency of photosystem II (Fv / Fm) and the efficiency of both photosystems I and II (PIABS). The levels of chlorophyll a, b and total and carotenoids in silica-treated plants showed a significant increase in Silica treatment, while they did not show any differences between 10 and 20 mM of potassium silicate. The results of the present study acclaimed that silica as an unnecessary mineral element for plant can improve the photosynthetic pigments contents in plants.

In order to evaluate the effect of integrated application of the combined chemical -farmyard manure and bio-fertilizer on yield and yield components of corn (S.C.703), in summer 2016, an experiment was conducted as split plot in randomized complete bock design with three replications in Ramhormoz - Iran. The main plots were consisting of four levels of chemical fertilizer (100, 50 and 25% of recommended NPK and no chemical fertilizer application (use of farmyard manure), and sub plots were consisting of three levels (no-inoculation; inoculation of seeds with biofertilizers containing growth-promoting bacteria and phosphate and potassium Solubilizing Bacteria (Azeto Barvar+Phosphate Barvar+Peta Barvar); seed inoculation with biofertilizers containing bacteria+Aspergillus fungus). The highest grain yield belonged to the 100% NPK, but between the two levels of 100 and 50% NPK consumption in terms of plant leaf number, ear length, ear diameter, number of rows per ear, number of grains per row and 1000-grain weight there was no significance difference. Grain yield and yield components were affected by biofertilizer application and there was no significant difference between the two levels of seed inoculation with biofertilizers containing bacteria and seed inoculation with biofertilizers containing bacteria+Aspergillus. In case of non-inoculation of seeds, with 50% reduction of NPK consumption, grain yield decreased by about 24%. However, by inoculation of seeds with biofertilizers containing bacteria and 50% reduction of NPK consumption, grain yield compared to 100% NPK consumption without inoculation Seeds was decreased about 12%. Therefore, co-inoculation of seeds with Azeto Barvar, Phosphate Barvar and Peta Barvar biofertilizers in combination with 50% of the recommended consumption of NPK chemical fertilizer is considered suitable for corn cultivation in Ramhormoz region due to reducing the cost of chemical inputs and preventing environmental pollution.

To evaluate of the role of remobilization in yield of corn (S.C. 704)in conditions of change of density and nitrogen, this experiment was conducted as a factorial based on randomized complete block design with three replications in Ramhormoz city, southwest of Iran, during 2015-2016 cropping season. a factor consisted of plant density per square meter (8, 10 and 12) and another factor of pure nitrogen consumption (from 46% urea source) included 50, 100, 150 kg. ha-1.The results showed that the plant density and nitrogen fertilizer significant effect on grain yield, biological, remobilization, remobilization and contribution of current photosynthesis is. The highest grain yield (8090.4 kg. ha-1) of 8 plants per square meter and the lowest (6480.1 kg. ha-1) were obtained from 12 plant per square meter. The highest grain yield (8650.7 kg. ha-1) was obtained from 150 kg. ha-1 nitrogen fertilizer treatment and the lowest (6160.7 kg. ha-1) was obtained from 50 kg. ha-1nitrogen fertilizer treatment. Most current photosynthesis and remobilization and current photosynthesis contribution of 8 plants per square meter and 150 kg of nitrogen per hectare, respectively. Most remobilization of 8 plants per square meter (143.1 g.m-2), respectively. Overall, the experimental results showed that consumption of 150 kg / ha of pure nitrogen at a density of eight plants per square meter could increase grain yield by 46% compared to consumption of 50 kg / ha nitrogen and a density of 12 plants per square meter and improve corn production.

A test was conducted in Achachi village by a split-plot factorial design in form of a completely randomized design model with three replications in 2017-2018. The treatments include three stress levels (a1: without stress (flooding), a2: irrigation interval per 10 days (from the beginning of clawing step), a3: irrigation interval of 20 days (since the clawing step), zeolite in two levels (b1: non-use (control), b2: 10 ton/ha), and cultivars in 4 levels (c1: Shahpasand, c2: local Tarom, c3: CT13382-8-3-M, c4: Sangjoo). The maximum yield was in a combination of flooding and zeolite use in cultivar of CT13382-8-3-M with an average of 5.9 ton/ha, and the minimum yield was in a combination of once every 20 days’ irrigation and non-use of zeolite in a cultivar of Shahpasand with the average of 1.06 ton/ha. The maximum transfer of the dry matter from the aerial parts was obtained when Sangjoo cultivar was irrigated once every 10 days in non-use of zeolite (816 kg/ha), and the share of grain re-transfer was reduced by increasing zeolite use. The other leaves have the main role of the dry matter re-transfer to the gain than the other parts (stem and flag leaf). In addition, its amount depends on the genotype and the environmental conditions and varied from -3.45 to 14.63%. The role of stems to transfer the dry matter to the grain was lower than the other aerial parts and in range of 2.5-16.7%. Totally, it seems that the re-transfer of the dry matter from the aerial parts of rice genotypes has an important role in filling the grains.

Considering the salinity problem and limited water resources in Iran, joint application of salinity moderators and super absorbents, can be an effective approach to improve the growth indexes of plants, grown in saline soils. For investigating the effects of salicylic acid and pumice on yield and nutrients content in Cress (Lepidium sativum) in a saline soil, a field experiment was conducted in a factorial form on completely randomized design with nine treatments and three replications. The factors were 1) salicylic acid (s) including three rates, consists of a) no amendment (control), b) soaking seeds in salicylic acid 0.1 mM for 24 h and c) spraying plants by salicylic acid 0.7 mM in three stages and 2) pumice (p) including three rates, consists of a) 0 (p0), b)15 T/ha (p1) and c) 30 T/ha (p2). Results showed that seeds soaking in salicylic acid 0.1 mM could moderate the negative effects of salinity in Cress. But there was not a significant difference between spraying plants by salicylic acid 0.7 mM and control, in most growth indexes. Increasing pumice rate, increased Dw and P, Ca, Mg and K content and reduced Na content, prolin, H2O2 and ascorbat peroxidase in Cress. Totally P2S1 treatment or application of 30 T/ha pumice and soaking seeds in salicylic acid 0.1 mM, produced the most Dw and nutrients content and the leastsalinity stress indexes in Cress.

In order to Assessment of the role of growth reduction factors on some morpho-physiological and yield indicators of rice cultivars an experiment in the year 2018 was conducted as split plot in a randomized complete block design with three replications. Experimentation factors included various rice varieties: Champa, Chermez-anbori and Hoveizeh in the main plot and reducing growth factors include: control (without cutting), consumption of half a liter of medax top in 45 days after planting, cut 65 days after planting to a height of 35 cm and cut 85 days after planting at a height of 35 cm in the subplot was. the results showed difference between levels of reducing growth factors in terms of stem height, panicle number, number of hollow seed per panicle and seed yield were at 1% probability and 1000-seed weight at 5% level. the difference between cultivars in terms of number of hollow seed per panicle at 1% level and 1000 grain weight at 5% probability level. highest number of hollow seed per panicle was in the control and the lowest in the cut 65 days after planting. the highest grain yield was obtained in the application of medax top with average of 4.7 tons/h and the lowest grain yield with average of 3.19 tons/h was obtained by cutting in 85 days after planting. so it can be cut by 65 days after the planting and use of the medax top or using the hoveizeh cultivar to reach the desired results in the region.