جستجوی مقالات مرتبط با کلیدواژه « oil percentage » در نشریات گروه « آب و خاک »

Many agricultural lands in Guilan province of Iran, especially paddy fields, remain uncultivated in the second half of the year due to various reasons including heavy rainfall, low soil permeability (stickiness of soil particles) and inefficiency of the existing drains. Mole drainage as a low-cost drainage method, proportion for rice cultivation conditions and easier to implement than pipe drainage, can be a suitable solution in the development of second cropping. Due to the oil content of 40% of the seed, the rapeseed plant is one of the valuable oil plants and has the ability to be cultivated as a second crop in paddy fields. Nitrogen plays a key role in the performance of plants and its deficiency causes limitations in plant production. Equipping paddy fields with mole drains along with the application of appropriate level of nitrogen fertilizer can increase the quantitative and qualitative yield of rapeseed as a second crop and contribute to the food security of the country. Therefore, the development of the cultivated area of rapeseed in paddy fields after rice harvesting in Rasht region, the study of the combined effect of mole drainage and different levels of nitrogen fertilizer on yield and yield components were the aims of this project.

In order to investigate the effects of mole drainage and nitrogen fertilizer on the yield and yield components of rapeseed as a second crop in Rasht rice fields, a factorial layout based on a randomized complete block design with three replications at the research field of the Faculty of Agricultural Sciences of Guilan University was implemented in the crop year of 2022-2023. The factors included mole drainage at three levels (without drainage, without gravel and with gravel) as D0, D1 and D2 respectively, and nitrogen fertilizer as urea source at two levels (180 and 240 kg ha-1) as N1 and N2 respectively. Rapeseed plant (Brassica napus) of Delgan cultivar was selected as the second crop after rice harvest. To carry out the experiment, at first the desired land was blocked and divided into plots, then the underground drains of mole were created without gravel and with gravel with a special blade in the desired plots. To drain the drainage from the mole drains, the polyca pipe was installed at the end of each mole tunnel, then the other side of polyca pipe was connected to the sub-pipe collection and finally led to the main surface drain. This experiment was conducted in 18 plots and each one was 9 × 6 meters. The distance between plots was 1.5 m, between replications was two meters, and the distance between plants was 15 and between rows was 25 cm. To avoid the effectiveness of drainage treatments from undrained treatments, undrained plots were considered at the end of the field. Before cultivation, basic chemical fertilizers, 200 kgha-1 of potassium from potassium sulfate source and 200 kgha-1  of phosphorus from ammonium phosphate source were applied. Nitrogen fertilizer from urea source was applied at the level of 180 and 240 kgha-1  in equal amount at three stages. Just before the harvest stage, to determine the traits of the number of seed in the pods of sub-branches, the number of seed per pod, the weight of seed in sub-branches, the weight of seed in the main branch and the weight of seed per plant, ten plants were randomly selected and harvested manually from the crown area. Also, to determine the seed yield, one square meter was randomly selected from each plot, taking into account the borders, and the bushes were manually harvested from the crown area. After the moisture content of the seeds reached the desired level, the seeds were separated from the pods and weighed using a laboratory scale with an accuracy of one thousandth of a gram, and the seed yield was calculated in kgha-1. SOXTEC SYSTEM HT 1043 Extraction Unit set was used to determine oil percentage and Kjeldahl set was used to determine seed protein. Statistical analysis of the data was done using SAS software (version 9.4) and comparison of means was done using the minimum significant difference test at 5% probability level. Excel software was used to draw the graphs.

The results of variance analysis of the data showed that the interaction effects of mole drainage and nitrogen fertilizer on the traits of seed weight in the main branches, seed weight in the plant and seed yield was significant at 5% probability level, so that the highest seed weight in the main branch with 0.733 seeds in the mole drainage with gravel with a nitrogen fertilizer level of 180 kgha-1 (D2×N1) treatment was obtained and the highest seed weight in the plant with 1.443 g in the mole drainage without gravel with a nitrogen fertilizer level of 240 kgha-1 (D1×N2) treatment was obtained. Also, the highest seed yield was obtained under 3579.48 kgha-1 in the treatment of mole drainage without gravel using 240 kgha-1 of fertilizer (D1×N2) which is compared to the treatment of without drainage and drainage with gravel with the same level of fertilizer 13.63 and 2.31 percentage was higher, respectively. In addition, rapeseed plant is more important in terms of oil percentage, no significant difference was observed between drainage and nitrogen fertilizer treatments in terms of average oil percentage. Therefore, the mole drainage treatment without gravel with a fertilizer level of 240 kgha-1 (D1×N2) is the most suitable option for rapeseed cultivation as the second crop after rice harvesting.

The results of this study showed that mole drainage without gravel by improving soil ventilation conditions and preventing waterlogging of paddy fields along with the level of nitrogen fertilizer of 240 kgha-1 increased the yield of rapeseed compared to the condition of without drainage at the same level of nitrogen fertilizer. Therefore, rapeseed cultivation in vast paddy fields after rice harvesting can be recommended as a basic solution in order to increase the production of oilseeds and provide part of the country's oil consumption.

In most arid and semi-arid areas, water limitations are one of the main reasons for the reduced plant growth and yield under irrigation and dry land (rainfed) conditions. The aim of this study was to compare the morphophysiological responses of rapeseed cultivars to supplementary irrigation and dryland conditions. For this purpose, an experiment was carried out as a split plot in the form of a randomized complete block design with three replications during 2017-2018 in the Gachsaran Agricultural Research Station. Irrigation treatments were at four levels (no irrigation=I0, supplementary irrigation at flowering stage=I1, supplementary irrigation at grain filling stage=I2, and supplementary irrigation at flowering stage+ grain filling=I3) in the main plot, and cultivars Hayola 401, R. J. S, and Shirali as factorial in the sub-plots. The results showed that supplementary irrigation increased plant height, number of sub-branches per plant, 1000- grain weight, grain yield, and oil percentage compared to rainfed conditions. With supplementary irrigation, the weight of 1000 grains increased by 32% compared to rainfed. Grain yield increased from 755 in rainfed conditions to 2350 kg.ha-1 with two supplementary irrigations. With two supplementary irrigations, the oil content increased by 11.8% compared to the rainfed conditions. In all irrigation treatments, grain yield and oil content of Hayola 401 were higher than R. J. S and Shirali cultivars. In general, supplementary irrigation improved morphophysiological traits, yield, and percentage of grain oil. In rainfed rapeseed cultivation, with supplemental irrigations at flowering and grain filling, water productivity increased from 0.21 to 0.53 kg m-3 grain yield from 755 to 2350 kg ha-1 and oil percentage from 35.4 to 36.9.

Climate change and inappropriate management activities have put pressure on limited freshwater resources. Water scarcity has led to better allocation of irrigation and it is expected that the allocation of water to the plant is planned according to the environmental conditions and growth stage of the plant. In order to investigate the effect of irrigation interval on morphological characteristics, yield components, yield and oil content on Evening Primrose (Oenothera biennis L.) plant, an experimental was carried out in randomized complete block design with five replications at Khorasan Razavi Agricultural Research and Education Center in 2019. Treatments included: irrigation intervals at three levels of 7, 10 and 14 days. The results showed the highest number of canopy (2833 cm2), dry weight of areal part (98 g/plant) and yield components, highest number of capsules per plant (427), seed weight per plant (5.33 g), grain yield per hectare (1921 kg), oil percentage (0.73%) and oil yield per hectare (275 kg) resulted from 10 days irrigation interval. With increasing irrigation interval from 7 days to 10 days was increased values in aforementioned traits and all studied traits was decreased by incremental irrigation interval from 10 days to 14 days. It seems that cultivated media containing fine textured soil due to the increase in surface area of soil constituents to their unit of weight has improved the favorable growth conditions in 10-day irrigation compared to 7-day irrigation. Therefore, application of irrigation treatment in 10 days increased water productivity efficiency in evening Primrose Flower in Mashhad weather condition.

The excessive uses of chemical fertilizers have generated several environmental problems. Some of these problems can be tackled by use of Biofertilizer, which are natural, beneficial and ecologically friendly. The Biofertilizers provide nutrients to the plants and maintain soil structure. Biofertilizer is an alternative to mineral fertilizers for increasing soil productivity and plant growth in sustainable agriculture. Plant growth promoting rhizobacteria (PGPR) are a group of bacteria that actively colonize plant roots and increase plant growth and yield. There is a widespread distribution of PGPR that flourishes in different geographical habitats. These rhizobacteria significantly affect plant growth not only by increasing nutrient cycling, also by suppressing pathogens by producing antibiotics and siderophores or by bacterial and fungal antagonistic substances and/or by other plant hormones. Inoculation of plants with Azospirillum could result in significant changes in various growth parameters, such as increase in plant biomass, nutrient uptake, tissue N content, plant height, leaf size and root length of cereals. Thus, it has been shown that Azospirillum and Pseudomonas have the potential for agricultural exploitation and can be used as natural fertilizers. The divers array of bacteria including Pseudomonas, Azospirillum, Azotobacter, Bacillus, Klebsilla, Entrobacter and Serratia seem to promote plant growth. These bacteria are important components of the rhizosphere of many plants, and are known to colonize the rhizosphere of wheat, potato, maize, grasses, pea and cucumber. Strains of Pseudomonas putida and Pseudomonas fluorescens could increase root and shoot elongation in wheat. Azospirillum, Pseudomonas and Azotobacter strains could affect seed germination and seedling growth To investigate yield, yield components and some qualitative and quantitative characteristics of safflower at different planting dates, a factorial experiment was conducted based on randomized completed block design with three replications in 2016 at the laboratory of Agricultural University of Payam Noor, Kosar (Kivi) branch. The first factor consists of three sowing dates (5 March, 20 April and 5 May) and the second factor involves the seeds inoculation with plant growth promoting rhizobacteria (no inoculation, seed inoculation with Azotobacter chorchorum strain 5 and Azosprilium lipoferum strain OF). The climate of studied region is semi-arid with 1350 meters altitude from sea level. Based on the soil test, pH was about 7.1, soil texture was loamy-sand and the depth of top soil was 70 cm. The experimental unit included six ridges of 25 cm in 6 m length. The plant density was 40 plants per m2. Each 1 gram bacteria have 107 no, we therefore used about 7 gr from each bacterium for seed inoculation. We also used Arabic gum to adhere the bacteria to the seed. The results showed that the planting date had a significant effect on all characteristics, except brain to grain ratio and the ratio of skin to grain. The effect of seed inoculation with plant growth promoting rhizobacteria was statistically significant on plant height, stem diameter, number of main and sub main branches, seed oil and protein percentage. The maximum number of boll per plant, number of grain per boll, 1000-grain weight, grain yield, biological yield, harvest index, plant height and protein percent were achieved on the first planting date (5 April). The lowest amounts of these traits were obtained on the third planting date (5 May). The maximum oil percentage, number of primary and secondary branches and stem diameter were obtained on the first planting date and seed inoculation by Azotobacter. The lowest rates of these traits were obtained on the third planting date and no inoculation. Thus, seed priming with Azotobacter and first date (5 March) planting are recommendable to increase number of grain per boll, 1000-grain weight, grain yield, biological yield, harvest index, plant height and protein percent and other traits.

In order to study the effect of foliar application of boron and zinc on yield and some qualitative characteristics of two rapeseed (Brassica napus L.) cultivars, a factorial experiment was carried out based on RCBD with 18 treatments and 3 replicates during 2005-2006 at Zanjan Agricultural Research Station. Factors of the experiment were: spraying of in 3 levels including Zn0 (without spraying), Zn1 (spraying with 3 g ZnSO4/L), Zn2 (spraying with 6 g ZnSO4/L) and H3BO3 spraying including B0 (without spraying), B1 (spraying with 2 g H3BO3/L), B3 (spraying with 4 g H3BO3/L) and the cultivars were V1 (SLM046) and V2 (Talayeh). Zn and B foliar applications were done in two plant phenological stages (early stemming and flowering). During the growth season common agronomic practices were followed and grain yield and concentration of oil, protein, Fe, Mn, Zn, Cu and B of rapeseed grains were measured at harvesting time. Results showed significant difference between the treatments, so maximum grain yield of 4180 kg/ha was obtained from Zn0B1 in V1 cultivar. Concomitant application of Zn and B led to increase in their concentrations in the grain that is important from rapeseed fortification view of point. Therefore, regarding to beneficial effects of B on grain yield and joint application of B and Zn on the seed quality simultaneous spraying of boric acid and Zn sulphate with 2 g /L and 3 g /L respectively in early stemming and flowering stages may be recommended for the study area and the similar regions.

A study was conducted in 2007 to investigate the effect of nitrogen fertilizer rates (0, 30, 60 Kg ha-1) on some agronomic characteristics, seed yield and oil percentage in three Sesame(Sesamum indicum L.) cultivars (Dashtestan, Darab 14, and Zarghan) in Kaki region (Bushehr Province). The type of design was completely randomized block with factorial arrangement and three replications. Nitrogen(N) fertilizer had a very significant effect on agronomic characteristics, such as number of capsules in the main stem, number of capsules per plant, branches /plant, biological yield, seed yield ,and oil percentage, but had no effect on 1000 seed weight. There was no significant difference between the application of 30 and 60 Kg of N fertilizer ha-1 with respect to harvest index. Seed yield increased as N rate increased, but each cultivar had a different response to different rates of nitrogen. Dashtestan and Zarghan had superiority over Darab 14 with respect to overall agronomic properties such as response to fertilizer and early maturity, but from the qualitative point of view, Darab 14 produced higher percentage of oil.

To determine the effects of different intensities of leaf removal at different reproduction stages of sunflower on seed yield and oil percentage, and the most sensitive stages to defoliation, an experiment was carried out by split-spilt plot design in randomized complete block with 3 replications at research farm, College of Agric. Urmia University, in 2004. The main factor, sub factor and sub-sub factor in our experiment were: 1. two cultivars, Uroflor and Alstar, 2. defoliation at four reproduction stages, star shape of inflorescence (R2), pollination stage (R5), seed setting initiation (R6) and final period of seed setting (R7), and 3. four defoliation intensities ( 0% as an undefoliated control, 25%, 50% and 75% ). Seeding was accomplished on May 23. Average triple factor interactions verified that different defoliations at R2 stage have significantly reduced seed yield and oil percentage of both Uroflor and Alstar cultivars. Out of this reduction, 75 percent defoliation at R2 was the most, while at R5 and R6 stages 50 and 75 defoliation caused significant reduction on seed yield in comparison with control. At R7 stage different defoliations had no significant effect on seed yield of Uroflor cultivar, while, on Alstar cultivar, 75 percent defoliation at R7 stage caused significant difference in relation to control. Also average triple interaction among factors showed that none of defoliation percentages had significant effect on oil percentage. In view of the fact that, seed development and filling occurred after defoliation at R2 and R5 , the most variation resulted from defoliation of valued traits like number of filled seed per head and weight of 1000 seeds, observed at R2 and R5 stages and consequently reduced seed and oil yields. On the bases of this experiment it could be concluded that sunflower cultivation with losses of 50 and 75 percent will be economically unprofitable and it will be more desirable to replace it with any other suitable crop in the region.