جستجوی مقالات مرتبط با کلیدواژه « seed » در نشریات گروه « منابع طبیعی »

Considering the questions about the reasons for the decline in the quality of corn seeds in Moghan, especially regarding the management of corn cob dryers, this experiment was conducted in order to diagnose the effect of the dryer function on seed quality. For this purpose, 24 samples of corn seed variety 704 were prepared in two stages from nine seed processing stations in 2018. 12 cobs from the shipment were transported from the field and before entering the dryer and 12 dried cobs of the same shipment were randomly registered and tested in the National Seed Quality Laboratory. In addition to laboratory tests, each sample was cultivated in the field in the form of a RCBD in three replications. According to the results there is no significant difference between the sampling time before and after drying. The interaction of processing station and sampling time, except in two stations, did not show any significant difference on seed quality indicators. Based on the results, in the stations with higher output seed quality, the cobs were harvested with a moisture content of 25-29% and aerated at a temperature of 32-35℃ and after reaching the average moisture content of the mass about 20%, the temperature increased to 38℃. According to the results, the dryers function has a minor role in causing damage to seeds and reducing seed quality, and due to the low germination power of seeds produced in farms, other factors including farm management are effective in reducing the quality of corn seeds.

Nowadays, the cultivation of vegetables in greenhouses using soilless beds has become a widely adopted practice for vegetable production worldwide. The inclusion of new greenhouse crops like melons offers the potential to supply consumers with fresh and high-quality produce. Greenhouse melon cultivation is a relatively new practice in Iran, and there is a scarcity of published information regarding its various aspects of production in a greenhouse setting. One crucial factor that significantly influences the quality and quantity of greenhouse crops, such as melons, when employing soilless cultivation techniques, is the selection of appropriate nutrient solutions. Therefore, the current study was conducted to investigate the influence of different nutrient solutions on vegetative growth, seed and fruit characteristics, and biochemical status of three melon cultivars (Ahlam, Polinica, Curie) under greenhouse condition.           

The present study was conducted at the Horticultural Sciences Department of Shahid Chamran University of Ahvaz in southwestern Iran during the 2017-2018. A factorial experiment based on randomized complete blocks design with three replications, was carried out to assess the impact of three nutrient solution treatments (Pars, Shizuoka, Hachmath) and three different cultivars (Ahlam, Polinica, Curie) on key characteristics of greenhouse melon. The melon plants of the three cultivars were cultivated in pots containing 8 L of a growth medium consisting of a 4:1 ratio of cocopeat to perlite. At the end of experiment, four characteristic groups including vegetative growth parameters (dry weight of leaf, root, stem and plant and the ratio of leaf dry weight to root dry weight), seed characteristics (seed dry weight and hundred seeds weight), physical parameters of fruit (length, diameter, weight, wide of seed cavity and flesh thickness) and biochemical traits (ascorbic acid content, carotenoid content, taste index, total soluble solid content and titratable acidity) were measured.

The findings demonstrated that in the Hochmuth and Pars nutrient solutions, the Ahlam cultivar exhibited the highest total dry weight (63.66 g and 37.65 g, respectively). However, the Polinica cultivar showed the highest total dry weight in the Pars nutrient solution. The Hochmuth nutrient solution resulted in the highest leaf dry weight for the Ahlam cultivar (43.77 g). The Ahlam cultivar also displayed the highest fruit weight (1584 g and 1510 g, respectively), dry weight of hundred seeds (4.04 g and 3.56 g, respectively), seed dry weight per fruit (11.56 g and 10.75 g), weight of seed cavity contents (104.10 g and 114 g, respectively), fruit diameter (13.51 cm and 13.58 cm, respectively), and fruit lengths (17.58 cm and 18.28 cm, respectively). The weight of seed cavity content was influenced by both the cultivar and the nutrient solution. The Ahlam cultivar, when fed with the Pars nutrient solution, exhibited the highest total titratable acidity (0.07 %) and seed cavity thickness (6.38 cm). Regarding the Polinica cultivar, the Pars nutrient solution resulted in the highest total soluble solids (11.98 %B) and taste index (337.3), while the Hochmuth nutrient solution led to the highest ascorbic acid content (1.05 mg g-1 FW). The nutrient solution treatments did not have a significant effect on carotenoid content of the melon cultivars. Different amounts of elements in different nutrient solutions cause different growth behaviors of plants. For instance, the melon plants fed with Pars nutrient solution showed higher values of growth parameters comparing to the other plants, and it could be related to high N content of this solution. The similar results have been reported on the other crops such as cucumber and tomato.

The outcomes of the current study, which investigated variations in vegetative growth, yield, and quantitative and qualitative traits of melon cultivars under different nutrient solutions, indicated that the genetic traits of the cultivar, vegetative growth, and quality attributes of melon fruit were influenced in the presence of cocopeat and perlite media. The findings suggest that prior to selecting a melon cultivar for greenhouse cultivation, it is crucial to assess the impact of various nutrients on both vegetative growth and the qualitative characteristics of the fruits. Conducting such experiments can enhance the efficiency of nutrient utilization in greenhouse melon production.

In order to investigate the effect of priming on different aspects of germination of aged pumpkin seeds under drought stress, a factorial experiment was conducted based on a completely randomized design with four replications in the laboratory. Treatments included different levels of aging (control, 85% and 75% of control germination), salt stress (0, 75 and 150 Mmol) and priming (control, hydro, gibberellin, GR24, benzyl aminopurine and spermidine). The seeds reached the desired vigor level by accelerated ageing test. Morphological traits were also studied using seedling growth test. Mobility of seed lipid reserves, carbohydrate, number of photosynthetic pigments, photosynthesis, α-amylase and the amount of sodium ions were measured. In the study of germination traits, motility of lipid reserves, carbohydrates, chlorophyll a, photosynthesis and sodium content, salinity stress, seed deterioration and priming led to a significant change in them compared to the control seed. While in the case of shoot and root dry weight, chlorophyll b, and chlorophyll a / b ratio under salinity, seed deterioration and priming, no statistically significant change were compared to the control seed, the greatest effect of gibberellin-related seed priming was observed on germination traits and spermidine on physiological traits.

This experiment was conducted at seed technology laboratory of Agricultural Sciences and Natural Resources University of Khuzestan, in 2018 with the to evaluate the effects of seed priming on cardinal temperatures and thermal time requirements of borage seed germination. The factorial experiment was arranged based on the randomized complete block design with three replications. Treatments were gibberellic acid (0 (distilled water as control), 100, 200, 400 mg/L-1), priming durations (6 and 12 hour) and seven levels of germination temperatures (5, 10, 15, 20, 25, 30 and 35 oC). Beta model, beta modified, dent-like and segmented were used to determine cardinal temperatures. Results showed that seed germination significantly increased at both priming durations of 6 and 12 hours with increasing of temperature and gibberellic acid concentrations. The highest seed germination was observed at 200 mg/L-1gibberellic acid and 15 oC. Increase of gibberellic acid concentrations resulted higher thermal time requirements to complete 50% of germination in seed population. From the results, the beta model provided the best fit to evaluate cardinal temperatures of borage seeds. It is therefore, suggested that the base, optimum and celling temperatures of borage seeds are 0.51, 21.5 and 35.1 oC and influenced by application 200 mg/L-1GA to 0.33, 23.5 and 35.8 oC.

Coriander seed (Coriandrum sativum L.) has essential oil, lipid and protein, and the lack attention to seed storage condition causes physical and physiological damage and ultimately decreasesits quality and deterioration so a factorial experiment in a completely randomized design was carried out and six levels of time storage (30, 60, 90,120,150 and 180 days), five level of seed moisture (5, 7, 9, 11 and 13 %) and four level of temperature (10,15,20 and 25 oc ) were studied. The results showed that the moisture content of 13% had severe harmful effects on seed germination at different temperatures compared to other humidity. In 5% moisture, an increase in temperature from 10 to 25 oc had no significant effect on germination indices especially seed germination percent and it was above 90 in all temperatures. The results of different seed packaging material showed that between aluminum, fabric, paper and cellophane, aluminum has less impact on the germination indices. The conclustion that can storage coriander seeds in the moisture content of 5% and aluminum packaging at temperature bellow 25 for long-term without a significant reduction in its maintenance.

To evalute the effect of Trichoderma fungus on potato productin in the presence of Rhizoctonia solani, a three replicated greenhouse experiment was conducted in a randomized complete block design. Treatments were three strains of Trichoderma (i.e. Trichoderma harzianum (TR), Trichoderma virens (Tr2), Trichoderma atroviride (Tr3)), Rhizoctoniasolani Ag3 fungus and Agria and Sante varieties of potato provided by the seed and plant certification and registration institute. Root and shoot dry weight, stolon dry weight and number, tubers number and fresh weight were measured. the results showed that Trichoderma tretmeant could have a significant effect on the traits in the presence of fungus (pathogen-infected condition). Also, the virulence was significant decreased as compared to the contorol. Tr1 - Agria variety combined treatment had mor significant effect on the measured traits than the other combined treatments, so that dry weight of shoot and stolons, fresh weight of tubers and the number of tubers was the highest in Tr1 tretmeant which was increased as compared to the control as 80, 52, 70 and 175 percentage, respectively. Also Tr1 Treatment increased Antioxidant enzyme activity and proline content, while decreased lipid peroxidation.

To understanding of effect of canopy gap disturbance on quantity and quality of seed germination of forest trees, seeds of two economic trees in Hyrcanian forest including Fagus orientalis and Carpinus betulus were collected from some canopy gaps with different sizes and their germination parameters were studied. In this regard, 48 canopy gaps were identified from a mixed Fagetum stand at Hajikola-Tirankli forestry plan from Tajan River watershed. In the following, the canopy gaps were classified to three difference size classes such as smaller than 150 (small), 150-350 (moderate) and 350-500 m2 (large) and the seeds of the Beech and Hornbeam were collected from inside and outside of the canopy gaps and seed germination test were done on the collected seeds. Seed germinant percent, germination speed and mean seed germination time were calculated and then statistically analyzed. Comparison of the collected data showed that there is no considerable difference between natural and artificial canopy gaps in aspect of seed germination parameters while for both species, collected seeds from moderate and large canopy gaps had higher seed germination and sometimes germination speed. It seems that optimal environmental condition such as moisture, temperature and light is better provided in canopy gaps bigger 150 m2 for seed germination of both species. Same research would be suggested on the other tree species.

In order to evaluate the effect of hydropriming on germination and seedling growth of Chickpea cultivars under drought stress this study was conducted in two separate experiments. In the first experiment the effect of hydropriming on the germination of two chickpea cultivars ILC6266 and MCC510 were studied in physiology laboratory. The second experiment was conducted in research greenhouse in same location. Drought treatments were 70, 50 and 30 percent of field capacity. Analysis of variance showed that increasing the duration of soaking in water to 24 hours, the germination percentage and germination rate increased 8 % and 25 % respectively. Seed priming increased radicle and plumule length of both cultivars, but the MCC 510 has a length of radicle and plumule was higher than the ILC 6266. Also with increasing duration of hydro to 24 hours seed length vigor of MCC 510 and ILC 6266 was increased 41% and 52% compared control condition. Based on the results of glasshouse drought severely reduced germination percentage of both cultivars, although somewhat priming could reduce the damaging effects of water stress as a priming for 24 hours could caused 100% percentage of emergence in the MCC 510. Both cultivars under drought stress in seedling death was caused without priming but The hydropriming for 24 hours could increase 74 percent dry matter chickpea cultivars compared control condition. In conjunction with plant weight vigor also increase drought stress caused a significant reduction of both cultivars in all levels of hydropriming.

At present experiment, the effects of moist stratification duration (at 7+1 oC) on seed germination and early seedling growth of three genotype of wild almond (Prunus scoparia) from Khuzestan province (southwest of Iran) were investigated. The seeds of P. scoparia were selected from wild almond trees in Masjed Sloeyman, Izeh and Dezful regions. After tip pinching, seeds of each genotype were stratified for 0, 15, 30 and 45 days. Results of germination test showed that stratification for 45 days increased seed germination percentage, seed germination rate and early seedling growth of all three genotype. The highest germination percentage were 68, 69 and 71 for Masjed Sloeyman, Izeh and Dezful, respectively. Seedling growth indices of each genotype (vigor index, root and shoot length and seedling dry weight) were increased after stratification for 30 to 45 days and also differences among responses of genotypes were statistically significant. The lowest germination vigor (0 and 43.75, respectively) were observed in seeds of Masjed Sloeyman and Dezful without stratification after 15 days stratification and for seeds of Masjed Sloeyman (84.5) after 30 days. Overall, results indicated that the stratification for 45 days after removal of seed coat and origin of seed significantly affect the germination and early seedling growth of P. scoparia genotypes form Khuzestan.

In this research, cleaning, drying and grading of corn seed were investigated in Ardabil provinces (Mogan zone). Beside investigation of corn seed drying and processing machineries, some items such as moisture changes of corn seeds, broken and cracked seeds studied during process steps in four seed process factories. Although the most seed breaking belong to the large and round seeds, the most cracked seeds observed in round seeds. Cracked seeds had increasing trend and direct relationship with moisture. Numbers and revolution speed of bucket elevators had direct effect on seeds physical damages. It may increase seed cracking more than 30 percent. In totality about 15 percent of seeds go out of process line as broken seeds. Besides 30 percent of seeds cracked during process. Endosperm damages increased risk of planting and cusses to lack or poor germination.

The main purpose of the present study is to investigate the stability of seed producing companies in the Khuzestan Province, I.R. Iran. This research is a causal-correlational survey. The statistical population consisted of all members of the board of directors of seed producing companies in the Khuzestan Province (N=72). Seventy two questionnaires were distributed using the full enumeration method. Finally, fifty questionnaires were collected and analyzed since a few of the members were not willing to respond to the questionnaires. A questionnaire was used for data collection which was satisfactory in terms of reliability and validity. After completing the questionnaire and data collection, the SPSS software package was used for data analysis. Based on the results of the present study, a significant relationship was found between information resources, social participation, social status and education level with the dependent variable set at the level of 0.001. Also, a significant relationship was observed between the land area, number of warehouses and silos, corporate income, educational courses and age with the dependent variable set at the level of 0.005. The results of stepwise regression showed that the social status, age and corporate income account for 57 percent of the variations of the dependent variable. Moreover, the results of factor analysis related to the stabilizing factors of the seed producing companies of the Khuzestan province showed that supporting and regulatory factors, education and empowering, standardization and satisfaction, application of new technologies and business skills allocate themselves a total of 70.25 percent of the variance of stability of the seed producing companies.

In order to study on effect of irrigation intervals and parent plant nutrition by various nitrogen levels on seed and seedling vigor and some related characteristics of hybrid maize single cross 704 (B73× MO17)a research conducted at Kermanshah province research station field of Agricultural and Natural Resources Research Centre and seed quality analysis laboratory of Seed and Plant Certification and Registration Institute (SPCRI) at Karaj.Field experiment based on complete randomized clocks design and as split plot by three replications conducted. Studied treatments levels arranged as7, 9, 11 and 13 day irrigation intervals as main plots and nitrogen rates 200, 300, 400 and 500 kg per hectare as sub plots. One thousand seed weight was determined and seed and seedling vigour tests including seedling growth analysis, radical emergence rate and electrocunductivity conducted based on complete randomized blocks design by four replications and final germination, normal and abnormal seedlings percent, mean germination time, seedling and primary root length, seedling and primary root fresh weigh, seedling and primary root and shoot dry weigh, seedling length and weight vigour index and electrical conductivity were measured. Results revealed produced seeds in 7 and 9 day irrigation intervals and 400 kg per hectare nitrogen from seed and seedling vigour and some related characters point of view had most optimum situation. Thereafter, based on this research results and for the reason of water resources for irrigation limitation, 9 day irrigation interval and 400 kg per hectare condition recommended forhybrid maize single cross 704 seed production in Kermanshah conditions.

In this research the effects of four levels of salinity(0, 5, 10 and 15 dS.m-1) on three cultivars of rapeseed (Okapi, Zarfam, and RGS) were studied. Salinity and cultivar carried out in completely block design in factorial arrangement with three replications. Germination and vigor tests were done on produced seeds in laboratory. Seed viability indices showed no significant difference. These traits were not affected by salinity.Normal seedling percentage in different varieties and salinity treatments were not significantly different. Some of The seed vigor indices such as root length were significantly different between varieties and RGS003had lowest root length, so shoot fresh weight in both standard germination and accelerated aging test increased with increasing salinity. Shoot dry weight increased with increasing salinity (non-significant) and decreased in higher salinity level (15dS.m-1). So the seed production under saline conditions, have no negative impact on seed viability and vigor and even some of the seed vigour indicators will be improved.

In order to evaluate the priming effects of gibberllic acid and potassium nitrate on germination and seedling growth characteristics of three populations Satureja sahendica،, an experiment was conducted. The treatments including plant populations (Majarition, Zeninjab and Osko), gibberllic acid (500, 250 ppm) and potasium nitrate (1%, 2%) and cold treatment in three replications arranged in factorial was carried out in greenhouse and laboratory conditions in Natural Gene Bank Group of Research Institute of Rangeland and Forestry in 2011- 2012. After seedling growth, traits including: percentage and speed of germination, root and shoot length , ratio of root length by shoot length, vigor index, normal seedlings, seedling length, fresh and dry weight and ratio of dry weight to fresh weight were measured in laboratory condition. Also in greenhouse, traits including: percentage and speed of emergence, root and shoot length , ratio of root length by shoot length, normal seedlings, seedling length, fresh and dry weight and ratio of dry weight to fresh weight were measured. Analysis of variance showed that there were significanc differences between populations, treatments and interaction of populations with treatments(5%) for all traits in both experimental conditions except for seed emergence percentage and shoot length in greenhouse condition. Comparing seed germination characteristics of three population showed that population of Mjarishen selected from East Azarbijan had higher vigor characteristics like seed germination (97%), speed of germination (15 sprout/day) and vigor index(41) than other populations in laboratory condition. In greenhouse condition, percentage and speed of emergence of Osko population as 17% and 1 sprout/day, respectively, were higher than other two populations. Effect of treatment on the populations showed that priming of the seeds with gibberllic acid were more effective for vigor traits like(germination speed, emergence speed and vigor index) than the other treatments in both experimental conditions.

Among the production factors, seed as the primary production factor plays an important role in the transfer and exploitation of genetic characteristics seeds aiming to increase qualitative and quantities of the yield. Among growth stages of plants, seed germination and emergence stages are the most critical growth stages and play a pivotal role in plant establishment in fields. In order to investigate the impacts of seed diameter size on characteristics of germination in three wheat )Triticum aestivum L.( cultivars, this study was conducted in 2008 in a research station of seed and plant certification and registration research institute, Karaj, Iran. The experimental factors were five seed diameters ) 2-2.2, 2.2-2.5, 2.5-2.8, 2.8-3 ,andgt;3 mm ( and three wheat cultivars )Mahdavi, Pishtaz and Bahar(. In laboratory, seeds from different size class from cultivars were planted in a completely randomized design with 3 replicates. Germination percentage, germination speed , seedling-length, radicle-length, plumule-length, seedling dry weights, radicle dry weights and plumule dry weights were measured. Data analysis showed that seed size had a significant impact on speed of germinations, radicle dry weights, plumule dry weights and seedling dry weights. Results indicated that germination speed significantly decrease with increasing seed size. The other traits showed significant increases with increasing seed size. Cultivar had significant impact on germination characteristics but germination percentage and germination speed were similar between cultivars. Mahdavi cultivarandrsquo;s seedling length and dry weight was dependent on 1000 number of seed weights, especially influenced by 2.5-2.8, 2.8-3 and andgt;3 mm seed diameter, Seed size may be equivalent to the amount of nutrients saved in seeds. Therefore larger seeds may produce vigorous seedlings. Significant interaction was observed for radicle-length, plumule-length and seedling dry weight. This study suggested that the wheat genotypes did not have similar performance regarding to the variation in seed sizes .

In order to consider the effect of sowing date on germination characteristics in seeds of Pinus brutia, a Complete Random block design with four replications and 60 vests per replication was performed and pure seeds of Pinus brutia were planted in two different dates including November 20 and February 1. At the beginning of growth season, germination was recorded every 5 days. Then results of parameters including germination, germination percent, energy, peak value, speed and capacity and survival were calculated in autumn and winter sowing date. The results showed significant effect of sowing date on germination. Suitable sowing date for seeds of Pinus brutia is autumn, which is optimal considering labor force scarcity in winter and decrease in costs.