نشریه تحقیقات بذر
پیاپی 40 (پاییز 1400)

In order to evaluate the effect of seed coating with biological and chemical substances, as biofertilizer on seed germination of cumin (Cuminum cyminum L.), this research was conducted in two separate sections as a factorial experiment in the form of completely randomized design (CRD) with four replications in lab and research greenhouse of Kashmar University Jihad Institute in Kashmar in 2018-2019. In the greenhouse, the first factor was coated with chemicals (Lamadur fungicides, Carboxyl Tirah fungicides, Topsin M. fungicides, Gaoucho insecticides, Cruz insecticides) and coated with biological materials (Trichofarm fungus, Biofarm bacterium and Probio 96 bacteria), and the second factor is the use of sterilized soil and soil containing fusarium and in the laboratory, the first factor include coating with chemicals (Similar to the greenhouse) and Also covered with biological materials (Similar to the greenhouse), and the second factor was the application of three temperatures of 5, 10 and 25 ° C. The results of the laboratory showed that the effect of coating, different temperatures and interaction effect of coating with different materials and temperatures on, seedling length, seed germination percentage, germination rate and SV II index at the level of 1% were significant. The results showed that the highest seedling length (7.5 cm) was related to untreated seed treatment at 10 ° C and the lowest (1.3 cm) in cleaning up seed+ Carboxyl Tirah fungicides + Gao Chu insecticide. The results showed that the highest germination percentage (0.245%) was related to untreated seed treatment at 5 ° C. Generally the results showed that in the laboratory control treatment at 10 ° C increase germination percentage and vigure of length seedling in compared to other treatments but in the greenhouse, the use of growth stimulating bacteria (PGPR) was recommended.

In order to investigate the effect of intensity (40 and 59 kHz), power (60, 80 and 100 watts) and duration (2, 4, 6, 8 and 20 minutes) of ultrasound waves on germination, growth and physiological characteristics of canola (Ekapi cultivar), a factorial experiment was carried out as completely randomized design in the Seed Technology Laboratory of the Faculty of Agricultural Sciences of Shahed University in 2019. Germination percentage, germination rate, average time required for germination, weight and length index of seedling vigor, seedling length, seedling dry weight and some physiologic parameters including chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content and relative water content were measured. The interaction of intensity, power of the device and duration of application of ultrasound waves affected all studied traits except germination rate, seedling dry weight and relative water content. The highest germination percentage of rapeseed seeds in the treatment composition was related to 59 kHz waves, 100 watts and 6 minutes with an average of 88.33%. The content of carotenoids, total chlorophyll, chlorophyll a and chlorophyll b were observed with an average of 22.57, 49.08, 22.62 and 26.47 μg/g fresh weight in the application of 40 kHz ultrasonic waves with a power of 80 watts for two minutes. Based on the results, it can be concluded that the use of ultrasound was able to improve the germination, growth and physiologic characteristics of rapeseed. Therefore, according to the conventional time-consumed seed dormancy breaking methods, the use of ultrasound as a new technology to break dormancy as an alternative to older methods is recommended.

Germination is a vital stage in the life cycle of plants and plays an essential role in seedling establishment and seed yield. In order to evaluate the interaction of vermicompost extract and drought stress on germination indices of chickpea plant, a factorial experiment was conducted in a completely randomized design with three replications at Khatam-ul-Anbia University of Technology in Behbahan. The study treatments were: vermicompost extract with levels of 0, 10, 15 and 20% by volume and drought stress with treatments of 0, -0.3, -0.6 and -0.9 MPa. Drought stress was induced by PEG 6000. The results showed that the interaction of vermicompost extract and drought stress on all germination indices was significant in chickpea seeds. In conditions without drought stress and stress of -0.3 MPa, application of vermicompost extract at levels of 10 and 15% by volume causes a significant increase in all studied indices such as germination percentage, germination speed and germination vigor, seed vigor index, endosperm consumption, length plumule and radicle, seedling length, plumule and radicle dry weight. The results under stress conditions of -0.6 MPa showed that the application of 10, 15 and 20% levels could have a positive and significant effect on germination percentage, germination speed and germination vigor, seedling length and plumule length compared to the control treatment. Under these conditions, levels of 10 and 15% of the extract significantly improved radicle dry weight, radicle length and seed vigor index compared to the control treatment. Under -0.9 MPa, the use of vermicompost extract at all levels caused a significant increase in germination percentage, germination speed and germination vigor compared to the control. In general, the results of this study showed that drought stress significantly reduced all the studied traits, but the use of vermicompost extract (especially levels of 10 and 15%) significantly increased germination percentage, germination rate, germination vigor, seed vigor index, cotyledon consumption, plumule and radicle length, seedling length, plumule and radicle dry weight were compared with control treatment (without using vermicompost extract).

In order to investigate the effect of allelopathy of different organs of Mexican marigold on germination and growth of weeds and crops, a factorial experiment was conducted in a completely randomized design with three replications in greenhouse conditions. The first factor consisted of 5 concentrations of marigold extract (0, 5, 10, 25, 50 and 100% of) and the second factor included three different parts of marigold organs (leaves, stems and roots). Different extracts of different organs of marigold were applied on weeds of amaranthus, white goosefoot, phalaris, ryegrass, wiled barley and corn. The results showed that with increasing the extract, germination percentage, germination coefficient, germination rate, root length, shoot length, fresh and dry weight of seedlings decreased and the lowest measurement traits were obtained at 100% concentration of the extract. Concentration of 50% of extracts of different organs of marigold (leaves, stems and roots) resulted in non-germination of weed seeds of amaranthus, phalaris and white goosefoot. Germination of ryegrass and maize was stopped at 100% of the extract. Root extract had a greater inhibitory effect on weeds of amaranthus and white goosefoot. While the inhibitory effect of stem extract on phalaris weed and corn was greater. In general, the results showed that among the studied weeds, phalaris germination was more sensitive than other weeds and more sensitive to other weeds, as at lower concentrations of the extract, germination percentage was stopped. Among the extracts of marigold, the root extract had the greatest effect on inhibiting weeds and corn. Marigold plant extract had more inhibitory effect on the roots of weeds and corn and the stems of these plants were less affected. Weeds with smaller seeds also became more sensitive to lower concentrations and their germination stopped.

Myrtus is a tree that has been widely used in land space in recent decades, as well as this medicinal property. The seed of this plant has dormancy and its dormancy should be broken by various treatments to provide germination. In order to investigate seed dormancy breaking treatments, the study was conducted in a complete randomized design with 4 replications in 2015 in the Horticulture Physiology Laboratory of Agricultural Sciences and Natural Resource University of Khuzestan. Treatments included: control, scarification with sandpaper for 2 minutes, soaking in water 4, 25, 50°C by 30, 60 and 90 minutes, application of potassium nitrate in concentration 100, 500, 1000 ppm with immersion time for 24 hours, use 50% sulfuric acid for 5, 10, 20, 40 minutes and then wash 3 times with distilled water, stratification at 4 °C with times of 10, 20, 40 days. The results of comparing the means showed that by applying 50% sulfuric acid treatment for 20 minutes, the highest germination rate was 64.25% and the highest germination rate was 12.8 units per day and the highest seed vigor (22.29 units). Was obtained. After this treatment, sanding was almost in the second place. The results also showed that some treatments such as 50% sulfuric acid for 40 minutes, potassium nitrate at a concentration of 1000 ppm and soaking in water at 50 °C for 90 minutes caused seed damage and reduced germination indices. In general, it was found that the main obstacle to seed germination was the seed coat.

In order to investigate the effect of priming and aging on Physiological and biochemical constituents of common bean seed a factorial experiment was conducted based on completely randomized design at the University of Mohaghegh Ardabili in 2020 with 3 replications treatments were aging (control and two levels of 88 and 78% germination) and priming (control, hydro-priming, priming by gibberellin (20 mg / l) and salicylic acid (100 mg / l)). In this experiment. To survey the effect of water potential on the process of water uptake by bean seeds, distilled water was used as water with zero potential. The weight of the treated seeds was measured every 15 minutes, 45 minutes, 1:30 minutes, etc. for 24 hours at 25 °C. The results showed that the highest Mean Daily Germination (MDG), Germination Rate (GR), Germination Coefficient (GC), Seedling Weight Vigor Index (SWVI) and Seedling Length Vigor Index (SLVI), Seedling Length (SL) were obtained by priming treatment with gibberellin and without aging. Aging reduced phytin stores and Water absorption, but increased priming types of measured traits. Also, Aging increased the Daily Germination Speed (DGS) and Allometry Coefficient (AC). In general, using gibberellin pre-treatment strengthened weak bean seeds physiologically and the treatment can be used to increase weak seed vigor.