Gibberellic acid and calcium chloride: stimulatory effect on seed germination and enhanced seedling vigor of okra (Abelmoschus esculentus (L.) Moench)

Poor crop establishment is one of the major constraints to obtain the higher potential of rice, particularly in areas prone to environmental stresses. Therefore, present study was conducted to evaluate the effects of potassium nitrate on germination dynamics, seedling growth and associated physiological and biochemical events of two rice cultivars. For this purpose, various seed priming treatments were tested in lab and greenhouse. The percent concentrations of potassium nitrate were 0.25, 0.50, 0.75, 1.0 and 1.25 in both lab evaluation and greenhouse experiment. Non-primed seeds were maintained as a control for comparison. The results depicted that soaking rice seeds at higher concentrations of KNO3 could delay emergence time and final emergence (%) in both cultivars under lab and greenhouse conditions. Seed priming with 0.75% KNO3 significantly increased the stand establishment and seedling vigor attributes of both cultivars compared with other concentrations and naked rice seeds both in lab evaluation and greenhouse screening. Similarly, highest values for photosynthesis rate, evaporation rate and CO2 index were observed in experimental units receiving primed seeds with 0.75% KNO3 under greenhouse screening. Interestingly, no variance was observed among both rice cultivars. Overall, higher seed emergence, seedling vigor and associated biochemical attributes due to seed priming with 0.75% KNO3 was associated with decrease in alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDH) activities in lab and greenhouse screening.

Introduction: In order to energize the seeds, accelerate the germination process and lessen environmental stress, a range of physiological and non-physiological treatments are available. Seed priming is one of these. It's an inexpensive, effective hydration technique that speeds up germination by increasing the pre-germinative metabolic process through controlled drying and hydration. Aims: The main aim was to evaluate effect of halo-priming with KNO3 on germination and vigour of seed. Materials and Methods: In the present study, which was conducted with three carrot genotypes and varying halo-priming concentrations and durations were employed. A completely randomized design with three replications was used. Three genotypes were Carrot Florence (G1), Deb Kuroda-1 (G2) and Deb Kuroda-3 (G3) with various concentrations and duration of KNO3 for halo priming viz. 2% for 24 H (T2), 2% for 18 H (T3), 3% for 24 H (T4), 3% for 18 H (T5), 4% for 24 H (T6), 4% for 18 H (T7) and non-primed seeds (T1). The different seed quality parameters such as time to 50% germination, mean germination time (MGT), germination index, germination Energy (%), root length, shoot length, fresh weight, dry weight, germination percentage and vigor index were recorded. Results and Discussion: Seed priming is a practical and affordable way to guarantee consistent seed development in field crops. It improves germination, vigour, nutrient uptake, water use efficiency, and the release of photo- and thermo-dormancy. Conclusion: Deb Kuroda-3 was the best genotype over all treatments. Consequently, 3% KNO3 pre-sowing treatment for 24 H is advised for carrot seed in order to improve seedling establishment and vigour.

A study on hydropriming with different durations (4, 8, and 12 h) tested the seedling vigor of glutinous corn. Ambient conditions (temperature: 30 ± 2 ˆC; relative humidity - 65 ± 5%) were used as the growing conditions for the hydro primed and unprimed seeds (control). The treatments were arranged in a Completely Randomized Design in four replicates. Results show that longer hydropriming of 12 h exhibited a higher germination index (GI), germination speed, seedling vigor, and lower mean germination time (MGT). The longer the hydropriming, the faster the germination of corn seeds than unprimed and shorter durations of less than 12 h. There was an increasing trend of GI as the hydropriming duration increased. However, the seedling length of 12 h hydroprimed seeds was similar to 4 and 8 h, but they exhibited longer seedlings than unprimed seeds. Likewise, 8 and 12 h hydro primed seeds displayed a comparable seedling vigor index, but they were significantly higher than 4 h and unprimed seeds. Thus, it can be recommended that to improve the seedling vigor of corn seeds, 12 h of hydropriming is needed due to its significant enhancement on the parameters than the unprimed and shorter hydropriming durations.

Foxtail millet is a nutritionally rich and climate-resilient cereal crop; however, poor germination and weak early seedling growth often limit its productivity. This study evaluated the effects of seed priming on germination, seedling vigor, yield attributes, and grain yield of foxtail millet through laboratory and field experiments. In the laboratory study, four foxtail millet varieties were subjected to six priming chemicals at two concentrations each, along with hydropriming and an unprimed control. Seed priming significantly influenced all germination and seedling vigor traits. The highest germination percentage (86.44%) and germination index (116.49), were recorded under NaCl priming at 10000 ppm. Maximum seedling vigor index (6.08), speed of emergence (86.51), germination energy (61.63) were achieved with NaOCl at 500 ppm, while the lowest germination performance occurred under CaCl2 at 20000 ppm. The shortest time to 50% germination (T50 = 1.55 days), mean germination time (MGT = 4.54 days) and seedling vigor index were obtained from no priming, while the longest T50 (2.0 days) and MGT (4.78 days) were recorded with KNO3 at 30000 ppm. The longest shoot (3.76 cm) and shoot dry weight (28.96 mg) were obtained with KNO3 at 15000 ppm, while the longest root (3.92 cm) and seedling length (7.51 cm) were recorded under NaOCl at 1000 ppm. The lowest shoot length (2.18 cm), root length (2.08 cm), seedling length (4.26 cm), shoot (12.03 mg), root (10.66 mg) and seedling (22.69 mg) dry weight were obtained from no priming. Based on laboratory performance, selected treatments were evaluated under field conditions. During the winter season, the highest grain (2.72 t ha-1) and straw (5.03 t ha-1) were recorded from BARI Kaon-2 × NaCl (10000 ppm). The highest grain yield obtained under this treatment combination was due to the production of the highest values for ear length (17.83 cm), ear weight (14.30 g), filled grains ear-1 (2918.33) and 1000-grain weight (2.56 g). Whereas, the lowest grain yield (1.17 t ha-1) was given by BARI Kaon-1 × no priming. In the summer season, the highest grain yield (3.93 t ha-1) was obtained from BARI Kaon-1 × NaCl (10000 ppm) this was due to the production of the higher values for most of the yield attributes by this treatment combination. In summer season, the lowest grain yield was obtained from BARI Kaon-4 × no priming. In conclusion, BARI Kaon-2 × NaCl (10000 ppm) performed best during the winter season, whereas BARI Kaon-1 × NaCl (10000 ppm) exhibited superior performance during the summer season. Seed priming with NaCl (10000 ppm) emerged as a seasonally robust strategy to improve germination, crop establishment, and yield of foxtail millet in Bangladesh.

Seed priming is currently a wide used commercial process that accelerates the germination rate and improves seedling uniformity in several crops. A laboratory study was conducted to evaluate the effect of grain priming treatments on barley grain germination and seedling growth under drought stress imposed by PEG-6000. The experiment was performed employing a factorial completely randomized block design with four levels of drought stress (0,10,20 and 30% PEG6000) and 14 priming treatments (dry, hydropriming, 5, 10, 15% PEG-6000; 500, 1000, 1500 mg/l KNO3; 25, 50, 75 mg/l thiamin; 50, 100, 150 mg/l sodium metasilicate) with five replications for each treatment. Germination percentage, germination index, energy of germination, mean germination time, seedling vigor, seedling length, 10 seedling fresh and dry weights were measured below the experimental conditions. Variance analysis results (ANOVA) showed extremely significant (p<0.05) variations between treatments in all traits. It had been discovered that increasing PEG concentrations up to 30% significantly decrease germination criteria and seedling growth traits and that priming treatments in most cases significantly increased all germination and seedling parameter. The most effective in this regard was 1000 mg/l potassium nitrate as compared with untreated control treatment. Priming treatments in most cases mitigates PEG effects as a major increase, particularly with 1000 mg/l potassium nitrate. It is concluded that potassium nitrate at 1000 mg/l is helpful to enhance drought tolerance of barley grain germination and seedling growth.

Background: Salinity affect germination and seedling growth of several crop species, many techniques are used to improve tolerance and development of plants. Priming is an effective technique that improves germination of several vegetables crop under saline condition. That's why, this experiment was carried to study the effect of seed priming with 5 g/L NaCI and KCI on germination and seedlings growth of safflower {Carthamus tinctorius) exposed to five levels of salinity (0, 5,10,15 and 20 g/L). Materials and Methods: Safflower seeds were soaked in solutions of NaCI (5 g/L for 12 h) and KCI (5 g/L for 24 h) at 20°C. Primed and non primed seeds were put to germinate in petri dishes and irrigated with saline solutions of five concentrations of NaCI (0, 5,10,15 and 20 g/L). Results: NaCI and KCI priming have improved germination parameters (germination percentage, mean germination time, germination index and coefficient of velocity) and growth parameters (radicle and seedling length, seedling fresh and dry weight and Vigour Index) of safflower under saline condition. Conclusions: The present study revealed that, under salt stress, NaCI and KCI priming could be used as a method to improve safflower seed germination. However, further studies are needed to highlight effects of NaCI and KCI seed priming on future growth and development of the culture.

In this study, the effect of different doses (0 (control), 50, 100, 200 ppm) gibberellic acid (GA3) treatment on the germination properties of Arısoy (C1), Crawford (C2) and Samsoy (C3) soybean cultivars were investigated. The experiments were factorial arranged in a completely randomized design with four replications. As a result of this study, final germination percentage (FGP), mean germination time (MGT), germination index (GI) value, germination energy (GE) value, seedling vigor index (SVI) value, seedling fresh weight (SFW), seedling dry weight (SDW) and seedling length (SL) were determined between 82-93%, 3-4.43 days, 27.8-37.3, 72-93%, 533-988, 0.57-0.71 g, 0.13-0.21 g, 6.5-10.6 cm, respectively. In terms of FGP, MGT, GI, GE, SVI, SL, SDW properties, a significant difference (P<0.01) was determined between cultivars, GA3 doses and cultivar x GA3 doses. Among the GA3 dose treatmens, FGP, GE, SVI, SL values with 100 ppm GA3 treatment and GI values with 150 ppm GA3 treatment reached the highest levels. MGT value was determined at the lowest 150 ppm GA3 treatment dose. Germination parameters were negatively affected with 200 ppm GA3 treatment dose. Responses of cultivars to GA3 doses were variable. In conclusion, seed priming with gibberellic acid (GA3) can be used to enhance germination properties of soybean cultivars.

Seed priming is a pre-sowing treatment used to reduce stress effects in crops .This technique has been used to increase the germination rate of seeds mainly under unfavorable environmental condition. Crop productivity faces many problems like that unavailability of suitable condition that causes unbalanced seedling growth and poor germination. Hormones are essential to improve plant growth, development, crop yield quality and quantity. Auxin is essential hormones that improves germination of seeds and reduce stress effects. Laboratory experiment was conducted to study the effect of seed priming using different concentrations of IAA and IBA on carrot seeds (Daucus carota). In laboratory experiment, three concentrations of IAA and IBA (75 ppm, 50ppm, 25ppm) treated with distilled water with priming duration of 24 hours. Experiment was laid out in CRD with three replications. Data was collected to investigate the effect of seed priming with IAA and IBA under these condition like that (fresh weight, dry weight, speed of germination, root length, seed length, seedling length, final germination rate, mean germination time and dry matter content). Maximum fresh weight, final germination percentage, seedling length, energy of germination, speed of germination and mean germination rate was recorded IBA 75ppm. Maximum dry weight and dry matter content was observed IBA 25ppm.Maximum shoot length was recorded IBA 50ppm. Non-significant difference was recorded in root length.

Seed priming is technique for controlled seed hydratation which allows activation of pre-germinative metabolic processes. It has been successfully used for improving germination parameters in different crops. The study was conducted in 2012, at the Institute of Field and Vegetable Crops, Novi Sad, Serbia, in order to assess the effect of seed priming on four germination parameters (germination, germination index, mean germination time and time to 50% germination) of sunflower in in vitro drought conditions. Drought conditions (-0.8 MPa) were simulated using PEG 6000. Seed priming was conducted with soaking seed in water and different KNO3 solutions (0.1, 0.5 and 1%) for 12 h. Seed priming treatment with 0.1% KNO3 showed the best results and improved germination parameters : germination index, mean germination time and time to 50% germination of untreated seed (control). Seed priming showed no improvement in germination percentage in comparison to the control. Control had high germination (98%) and there was no possibility for its significant improvement with seed priming. This study showed that seed priming could improve some germination parameters of sunflower seed in in vitro drought conditions. Seed priming could be used as a simple method for overcoming problems related to a poor germination and seedling establishment in soil drought conditions. Main advantages of seed priming method are its simplicity and no requirements for expensive equipment and chemicals.

An experiment was conducted to study the effect of priming treatments on artificially aged seed germination and seedling growth of guava (Psidium guajava L.) at Department of Seed Science and Technology, CCS Haryana Agriculture University, Hisar during 2019–20. It is comprised 21 treatments in complete randomize design with three replications. There were five priming methods with different treatments under study i.e. tap water, GA3 (at 500, 700 and 1000 ppm concentration), KNO3 (at 0.5 and 1% concentration), thiourea (at 0.5 and 1% concentration) and HCl (at 5% and 10% for 2 and 4 min). Duration of tap water, GA3, KNO3 and thiourea soaking was kept 24 and 48 hours. The study revealed that priming the artificially aged seeds in KNO3 greatly increased germination, especially soaking of artificially aged seeds in KNO3 at 1% for 48 h which shows up to 45.0% germination. Parameter like germination%, mean germination time, seedling length, seedling dry weight and seedling vigour were positively affected by all the priming treatments. Artificially aged seed viability decreased but the standard germination efficiently increased due to priming treatments. KNO3 at 1% for 48 h improved germination and resulted in maximum dry weight of seedling (206.0 mg), seedling length (4.16 cm) and vigour index I and II (187.0 and 9271.0) in laboratory. Artificially aged seeds without any priming treatments showed poor growth and germination.

Background: Blackgram (Vignam ungo L.) is one of the most important legume crops, grown all around the world. It is used as a vegetable, feed, food and fodder purpose. Blackgram has lower germination and production because of its hard outer covering. To improve germination and seedling vigour, priming alters the physiological state of the seed. This change may improve germination uniformity, increasing seed vigour or physiology. Primed seeds generate seedlings that germinate faster and more uniformed than unprimed seeds and these early seedlings are frequently more robust and resistant to biotic and abiotic stresses. This is a time-saving and low-cost strategy that farmers may employ to improve crop stand and productivity while reducing cost. Methods: The experiment was carried out in 2016-2017 at Department of Genetics and Plant Breeding, SHUATS, Prayagraj. Blackgram (var. PU-31) seeds were primed with Hydro, Halo, Osmo and Organic priming at 12 hours. Then, four replications of the Complete Randomized Block Design were used to test seeds for germination and vigour. Result: The experimental results indicated that seed primed with PEG6000@ 20% had the highest germination, seedling length and vigour indices, followed by CaCl2@ 1%, when compared to control and other treatments.

Bu çalışma; aspir çeşitlerinin çimlenme ve çıkış dönemlerinde tuz (NaCl) stresine karşı tepkilerini belirlemek amacıyla yürütülmüştür. Denemede Asol, Balcı, Dinçer, Linas ve Olas çeşitleri materyal olarak kullanılmıştır. Araştırmada aspir tohumlarına çimlenme ve çıkış döneminde saf su (kontrol) ile 3 farklı NaCl (100 mM, 200 mM ve 300 mM) dozu uygulanmıştır. Çimlenme denemesi, petri kaplarında tesadüf parselleri faktöriyel deneme desenine göre 4 tekerrürlü olarak iklim dolabında karanlıkta (25 °C) yürütülmüştür. Çıkış denemesi ise torf (3/4), perlit (1/4) karışımı ile doldurulan kaplarda yürütülmüştür. Sonuç olarak; aspir çeşitlerinin çimlenme oranı %69-100, hassaslık indeksi 1.00-1.67, çıkış oranı %5.00-97.50, fide uzunluğu 13.4-115.9 mm, yaş fide ağırlığı 0.077-0.476 g, yaş kök ağırlığı 0.11-0.061 g, tuza tolerans yüzdesi %11.4-28.6 arasında tespit edilmiştir. Ayrıca ortalama çimlenme süresi (gün), çimlenme indeksi, ortalama çıkış süresi (gün), kök uzunluğu (mm), kuru fide ağırlığı (g), kuru kök ağırlığı (g), ve çıkış indeksi özellikleri de incelenmiştir. Deneme sonucunda; tuz dozlarının artmasıyla birlikte çimlenme süresi, (gün) hassaslık indeksi ve ortalama çıkış süresi (gün) değerleri önemli ölçüde artmıştır. Çimlenme indeksi, çıkış oranı (%), fide uzunluğu (mm), kök uzunluğu (mm), yaş fide ağırlığı (g), yaş kök ağırlığı (g), kuru fide ağırlığı (g), kuru kök ağırlığı (g), tuza tolerans yüzdesi (%), ve çıkış indeksi gibi değerler azalmıştır.

This study was conducted during the years of 2007, 2008 and 2009 in the green house and Laboratory of the Department of Horticulture, Faculty of Agriculture, Suez CanalUniversity, Ismalia, Egypt.This experiment was carried out to study the effect of seed priming under different levels of salinity on seed germination, seedling growth and field behavior of tomato. Under laboratory conditions, low salinity level (1500 ppm) or un saline (control) recorded maximum values of germination percentage (GP%), germination performance index (GPT) and coefficient of velocity and minimum values of mean germination time (MGT) , uniformity germination and T50 % and tallest seedling. Maximum values of fresh and dry weight/ seedling, total carbohydrate, total phenol and peroxidase enzyme activity were also recorded under low salinity level. Seed priming in KCl was the superior treatment for enhancing GP%, GPI, coefficient of velocity, both fresh and dry weight with no significant differences with NaCl with respect to coefficient of velocity. Under green house conditions, low salinity at 1500 ppm significantly increased growth rate, leaf production per week, both fresh and dry weight as well as number of leaves / plant, concentration of chlorophyll a and b as well as carotenoides in leaf tissues of tomato compared with other treatments or control. Seed priming in PEG significantly increased growth rate, leaf production per week, both fresh and dry weight and number of leaves/ plant, concentration of chlorophyll a and b as well as carotenoides in leaf tissues of tomato. The interaction between seed priming and salinity levels showed a significant effect on seedling growth and chemical constituents of germinated seeds of tomato. This study was conducted during the years of 2007, 2008 and 2009 in the green house and Laboratory of the Department of Horticulture, Faculty of Agriculture, Suez CanalUniversity, Ismalia, Egypt.This experiment was carried out to study the effect of seed priming under different levels of salinity on seed germination, seedling growth and field behavior of tomato. Under laboratory conditions, low salinity level (1500 ppm) or un saline (control) recorded maximum values of germination percentage (GP%), germination performance index (GPT) and coefficient of velocity and minimum values of mean germination time (MGT) , uniformity germination and T50 % and tallest seedling. Maximum values of fresh and dry weight/ seedling, total carbohydrate, total phenol and peroxidase enzyme activity were also recorded under low salinity level. Seed priming in KCl was the superior treatment for enhancing GP%, GPI, coefficient of velocity, both fresh and dry weight with no significant differences with NaCl with respect to coefficient of velocity. Under green house conditions, low salinity at 1500 ppm significantly increased growth rate, leaf production per week, both fresh and dry weight as well as number of leaves / plant, concentration of chlorophyll a and b as well as carotenoides in leaf tissues of tomato compared with other treatments or control. Seed priming in PEG significantly increased growth rate, leaf production per week, both fresh and dry weight and number of leaves/ plant, concentration of chlorophyll a and b as well as carotenoides in leaf tissues of tomato. The interaction between seed priming and salinity levels showed a significant effect on seedling growth and chemical constituents of germinated seeds of tomato.

Crops face moisture stress during the germination and early seedling stages. Seed priming has proved to be an effective technique to resolve the issue. With the objective of studying the effect of gibberellic acid (GA) on germination and early seedling growth of three crops under drought conditions, a two-factor factorial experiment was conducted with a completely randomized design with the replicates for three crops separately. The drought factors were three different levels (no stress, moderate stress (0.5 MPa) and severe stress (1.5 MPa) environments using NaCl) and methods of priming (GA-100 ppm) and hydropriming as control) on rice, black gram and rape seed at Agronomy lab of Lamjung Campus. Number of seeds germinated each day were counted and the root and shoot length were also measured till the 13th day. The results revealed that seed germination was sensitive to drought stress, as the mean germination time, germination index, seedling vigor index, coefficient of velocity of germination and seedling length with increasing stress in each crop (P-0.05) However, hydro-priming and Gibberellic Acid (GA), showed no significant difference in any parameters of any crops under various stress conditions Thus, hydropriming is suggested to overcome stress effects and further research with different concentrations of GA, with different priming period can be carried out to overcome the stress situations irrespective of the starch, protein, and lipid content of the seeds.

Poor germination in fodder crops is one of the major reasons responsible for lower than potential green forage yield of cereals. Invigoration treatments aids to promote and accelerate germination, increase the vigour of seedlings, and improve stand establishment in field, vegetable, and horticultural crops. Therefore, a study was carried out to evaluate the effect of different seed invigoration treatments on seed quality parameters viz., germination, field emergence, speed of germination, seedling length, dry weight and seedling vigour in fodder maize (Zea mays L.). The experiment was laid out in factorial completely randomized design with two factors i.e., months and treatments having 5 different seed priming treatment combinations i.e., - Priming with water for 12 hrs., - Priming with NaCl @ 4 g / litre of water for 8 hours., - Priming with Poly Ethylene Glycol solution @ 10g / litre of water for 8 hours., – Priming with GA3 @ 0.2 g / litre of water for 8 hours and - Control (unprimed seeds) and the treatments were replicated four times during Rabi, 2022-23 at the Department of Seed Science and Technology, Seed Research and Technology Centre, College of Agriculture, PJTSAU, Rajendranagar, Hyderabad, Telangana. The results obtained from this study indicate that hormonal priming with GA3 can be successfully employed to improve germination, field emergence, seedling length, dry weight, and seedling vigour in fodder maize (Zea mays L.). At the end of the study, it was observed that hormonal priming with GA3 had a significantly positive influence on mean germination per cent (90%), field emergence (87%), speed of germination (20.221%), seedling length (34.17 cm), dry weight (0.792 g), seedling vigour index-I (3082.05) and seedling vigour index-II (71.42) over the control.