Seed Soaking Treatment Research Articles

Regulation of seed soaking with indole-3-butyric acid potassium salt (IBA-K) on rapeseed (Brassica napus L.) seedlings under NaCl stress

The growth and yield of rapeseed are significantly hampered by salt stress. Indole-3-butyric Acid Potassium Salt (IBA-K) has been found to alleviate the impact of salt stress on plant growth. However, the regulatory effect of IBA-K dipping on salt-stressed rapeseed remains unclear. To explore the implications of IBA-K on the growth and development of rapeseed during the seedling stage, we conducted potting experiments using the Huayouza 62 variety. Five different concentrations of IBA-K for seed soaking (0, 10, 20, 40, 80 mg·L− 1) were tested. The promotional impact of IBA-K on rapeseed demonstrated an initial increase followed by a decline, reaching a peak at 20 mg·L− 1. Therefore, 20 mg·L− 1 was determined as the optimal concentration for subsequent experiments. To further understand the mechanism of IBA-K’s action on salt-stressed rapeseed seedlings, we utilized the moderately salt-resistant cabbage rapeseed variety Huayouza 158R and the highly salt-resistant Huayouza 62 as specimens. The investigation focused on their response and repair mechanisms under 150 mmol·L− 1 NaCl stress. The findings demonstrated that compared with the sole NaCl stress, the 20 mg·L− 1 IBA-K seed soaking treatment under salt stress significantly enhanced the plant height, stem diameter, and leaf area of both rapeseed varieties. It also led to greater biomass accumulation, increased chlorophyll content, and improved photosynthetic efficiency in rapeseed. Furthermore, this treatment bolstered the activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), while significantly reducing the levels of electrolyte leakage (EL) and malondialdehyde (MDA). Consequently, it alleviated the membrane lipid peroxidation damage induced by NaCl stress, enhanced the accumulation of soluble proteins, maintained cellular osmotic pressure, and effectively mitigated the adverse effects of NaCl stress on rapeseed.

Studies on seed germination of khirni (Manilakara hexandra L.) seedlings under shade net house condition

Studies were carried out on seed germination and subsequent growth of Khirni (Manilkara hexandra L.). seedlings under shade net house condition at Department of Horticulture, Late Shri. Vasantrao Naik Marahwada Agricultural University, Parbhani (M.S.), India during the year 2006-07 and 2007-08. Among the various seed soaking treatments given to Khirni seed, GA3 200 ppm seed soaking treatment for 24 hours was the best for increasing germination percentage and subsequent growth of Khirni seedlings under shade net house condition. While the treatment control i.e. no soaking recorded least germination percentage and subsequent growth of Khirni seedlings.

Effects of Exogenous Isosteviol on the Physiological Characteristics of Brassica napus Seedlings under Salt Stress.

In this paper, the effect of isosteviol on the physiological metabolism of Brassica napus seedlings under salt stress is explored. Brassica napus seeds (Qinyou 2) were used as materials, and the seeds were soaked in different concentrations of isosteviol under salt stress. The fresh weight, dry weight, osmotic substance, absorption and distribution of Na+, K+, Cl-, and the content of reactive oxygen species (ROS) were measured, and these results were combined with the changes shown by Fourier transform infrared spectroscopy (FTIR). The results showed that isosteviol at an appropriate concentration could effectively increase the biomass and soluble protein content of Brassica napus seedlings and reduce the contents of proline, glycine betaine, and ROS in the seedlings. Isosteviol reduces the oxidative damage to Brassica napus seedlings caused by salt stress by regulating the production of osmotic substances and ROS. In addition, after seed soaking in isosteviol, the Na+ content in the shoots of the Brassica napus seedlings was always lower than that in the roots, while the opposite was true for the K+ content. This indicated that under salt stress the Na+ absorbed by the Brassica napus seedlings was mainly accumulated in the roots and that less Na+ was transported to the shoots, while more of the K+ absorbed by the Brassica napus seedlings was retained in the leaves. It is speculated that this may be an important mechanism for Brassica napus seedlings to relieve Na+ toxicity. The spectroscopy analysis showed that, compared with the control group (T1), salt stress increased the absorbance values of carbohydrates, proteins, lipids, nucleic acids, etc., indicating structural damage to the plasma membrane and cell wall. The spectra of the isosteviol seed soaking treatment group were nearly the same as those of the control group (T1). The correlation analysis shows that under salt stress the Brassica napus seedling tissues could absorb large amounts of Na+ and Cl- to induce oxidative stress and inhibit the growth of the plants. After the seed soaking treatment, isosteviol could significantly reduce the absorption of Na+ by the seedling tissues, increase the K+ content, and reduce the salt stress damage to the plant seedlings. Therefore, under salt stress, seed soaking with isosteviol at an appropriate concentration (10-9~10-8 M) can increase the salt resistance of Brassica napus seedlings by regulating their physiological and metabolic functions.

The Exogenous Application of 24-Epibrassinolide (24-EBL) Increases the Cd and Pb Resilience in Zea mays (L.) by Regulating the Growth and Physiological Mechanism.

Heavy metals (HMs) at a concentration above the thresholdlevel act as environmental pollutants and very often threaten theagricultural productivity globally. Finding affordable and environmentally sustainable deliverables to address this issue is therefore a top focus. Phytohormones alleviate the HMs-induced toxicity and positively influence the plant growth. Considering the importance of phytohormones, the present study aimed to assess the effect of 24-epibrassinolide (24-EBL; 10 µM) as seed soaking treatment on growth performance of Zea mays (L.) contaminated separately with increasing concentrations (50-400 mg.kg-1) of lead (Pb) and cadmium (Cd). With increasing metal concentrations, growth and plant biometric criteria were reduced. For instance, Cd at 400 mg.kg-1 soil reduced the germination efficiency (56%), root (77%) and shoot (69%) dry weight, total chlorophyll (64%), and carotenoid content (45%). Contrarily, both HMs caused increase in stress biomarkers and antioxidant enzymes in seedling. However, exogenous administration of 24-EBL significantly enhanced the growth attributes, photosynthetic pigments, proline, MDA, and antioxidant enzyme activity while reducing the harmful effects of HMs stress on Z. mays. For instance, 24-EBL (10 µM) improved the germination percentage, root biomass, chl a, chl b, total chlorophyll, and carotenoid content by 16, 21, 17, 34, 18, and 15%, respectively, in 50 mg.Pb.kg-1 soil-treated Z. mays plants. Furthermore, the amounts of proline, MDA, and antioxidant enzymes in foliage of Z. mays were interestingly and dramatically lowered by 24-EBL application. Uptake of metals in plant organs was significantly reduced when 24-EBL was applied to Pb- and Cd-treated Z. mays. The recent findings help us better understand how 24-EBL regulates growth and development of Z. mays as well as how it boosts HMs' resilience, which could increase the possibility of employing 24-EBL to increase Z. mays productivity. Thus, the present findings confirmed the potentiality of pre-soaking the seed in 24-EBL solution that neutralizes the toxic effects of heavy metals in Z. mays plants. Therefore, it is suggested that applying phytohormones including 24-EBL in removal of heavy metal stress in plants is the best possible solution in sustainable agriculture.

استجابة النقع بمستخلص (الأكاديان) في قوة بذور الحنطة تحت الأجهاد الملحي

A laboratory experiment was carried out in the laboratories of (Seed Examination and Certification Department of the Ministry of Agriculture and Postgraduate Laboratories- College of Agricultural Engineering Sciences - University of Baghdad) in 2021-2022, to determine the best combination of acadian concentration (seaweed extract) 0, 1500, 2000 and 2500 mg/L , under three levels of salt stress 5, 10 and 15 dS/m as well as control treatment through traits of seedlings of wheat (cv. Tammuz). A factorial experiment was applied according to a completely randomized design with three repetitions. The seed soaking treatment was superior to the concentration 2500 mg/L in the first count, final count, radicle length, stalk length, seedling strength index, and seedling dry weight. The salt tensile level 15 dS/m negatively affected the averages of all studied traits. The combination 5 dS/m × 2500 mg/L recorded a significant superiority in (first count, radicle length, stalk length, seedling strength index). A combination of 0 NaCl × 2500 mg/L significantly in the final count.

PENINGKATAN KUALITAS PERKECAMBAHAN BIJI CENDANA (Santalum Album LINN.) DENGAN LAMA PERENDAMAN MENGGUNAKAN AIR KELAPA DAN BAWANG MERAH

Sandalwood (Santalum album Linn.) is an endemic plant that is the identity of the people of East Nusa Tenggara (NTT). Generative propagation by means of seed soaking treatment is one of the alternatives to sandalwood plant propagation. Factors that are known to affect the success of plant propagation are Growth Regulators (ZPT) and the duration of soaking. This study was conducted to determine the use of coconut water and shallots as well as the effect of soaking duration for sandalwood growth. The research method uses a Complete Randomized Design (RAL) using a factorial design of 2 (two) factors, namely the first factor in the use of coconut water and shallots consisting of 3 levels, namely aquades (control), air kelapa 75% and bawang merah 75% and The second factor includes the length of soaking which consists of 3 levels, namely the Soaking Time of 9 Hours, 18 Hours, and 27 Hours. The results of this study showed that the treatment of the use of Coconut Water and Shallots and the combination of treatments did not have a real effect on germination, germination speed index, germination value and wet weight, while the length of soaking had a significant effect on the germination power and has avery noticeable influence on the sandalwood germinating speed index (Santalum album LINN).

Improvement of seedling quality of red jabon (Neolamarckia macrophylla (Roxb.) Bosser) through seed sowing techniques and seed invigoration

Red jabon (Neolamarckia macrophylla) is one of potential tree species, but there are some problems in its cultivation. Intermediate seed character and very small seed sizes with little food reserves often cause the low germination, low growth of the seedlings, and the sowing of the seeds to be too dense, resulting in an abnormal number of seedlings. The purpose of the research was to improve the seed germination and seedling quality of red jabon by adjusting the sowing density and seed invigoration treatment using hormonal and biopriming. Two experiments were conducted, that is, (1) identification of optimal seed density on the several combinations of sowing media (top soil, rice husk and compost) and (2) evaluation of the most suitable hormonal priming (GA3) and biopriming (liquid organic fertilizer, LOF) applications. The use of top soil media with a seed density of 0.5 g/400 cm2 can produce the highest pure live seed (PLS), that is, 721.67 seedlings/0.5 g. The seed treated by hormonal and bio-priming significantly affected the seed germination and seedling growth. Soaking seed in GA3 100 ppm for 4 days produced the highest of the PLS (764 seedlings/0.5 g), followed by soaking in LOF for 3 days and GA3 50 ppm for 4 days. The highest seedling height was generated from soaking the seeds using LOF for 3 days. The highest root collar diameter and biomass of red jabon seedlings were obtained from the treatment of seeds immersed in the GA3 50 ppm for 3 days. The best quality index value of red jabon seedlings was produced from the treatment of seeds immersed in the hormone GA3 50 ppm for 3 days. In general, a sowing density of 0.5 g/400 cm2 in top soil media and seed soaking treatment in GA3 50 ppm or LOF for 3 days can improve germination and growth of red jabon seedlings.

Physiological and Biochemical Mechanisms of Exogenous Melatonin Regulation of Saline–Alkali Tolerance in Oats

Saline–alkali stress is one of the major factors limiting oat seed germination. The regulatory role of melatonin (MT) as a naturally occurring active substance is well known, but the mechanism of MT-mediated intrinsic physiological regulation of oat seed germination under saline–alkali stress is unclear. Therefore, this study investigated (1) the variability of different MT seed soaking concentrations and times on the germination of oat seeds under saline–alkali stress, and (2) the possible physiological regulatory mechanisms of MT on the germination of oat seeds under saline–alkali stress. The results showed that seed vigor was significantly reduced under saline–alkali stress, and seed germination of oats was significantly inhibited; different concentrations of MT seed soaking treatments improved the germination rate, germination potential, germination index, vigor index, root length, germ length, fresh weight, and dry weight; and, overall, treatment improved seed germination and exhibited the phenomenon of “low promotion and high inhibition”. The 100 μmol·L−1 MT seed soaking treatment effectively enhanced the activities of seed antioxidant enzymes (SOD, POD, CAT, and APX) and nonenzymatic antioxidants (GSH and AsA), affected the AsA-GSH cycle, and effectively increased the contents of osmoregulatory substances (proline, protein, and soluble sugar) by reducing levels of H2O2, OH−, and MDA, thus enhancing the tolerance of oats to saline–alkali and promoting seed germination. In conclusion, MT has a positive effect on the saline–alkali tolerance of oat seeds.

Paenibacillus terrae NK3-4 regulates the transcription of growth-related and stress resistance-related genes in rice.

Paenibacillus terrae NK3-4 is a plant growth-promoting rhizobacterium. In this study, the effects of NK3-4 on rice growth and gene transcription were determined. The results indicated that a seed soaking treatment and a pre-germination seed treatment using NK3-4 promoted rice growth, especially spraying rice seedlings with NK3-4 increased the root number and root length by 34.2% and 34.1%, respectively. Moreover, NK3-4 induced the differential transcription of genes annotated with gene ontology (GO) terms; the number of up-regulated genes was 4.38-times higher than the number of down-regulated genes. The NK3-4 treatment induced the differential transcription of genes in 1794 GO functional groups, with 1531 functional groups containing up-regulated genes. Specific growth-related genes up-regulated by NK3-4 are involved in biological processes, including responses to auxin, hormone biosynthesis, cellular component biogenesis, root system development, and other functions. Furthermore, stress resistance-related genes were up-regulated, some of which encode WRKYs, NPK1-related protein kinase, NPR1-like 4, CaM-like proteins, MYBs, ERFs, TIFYs, NACs, EL5s, PR1s, PR2, PR8, PODs, and PAD4. Considered together, these findings imply that NK3-4 may promote plant growth and enhance stress resistance by regulating gene expression, making it a potentially useful microbe for regulating rice growth and stress resistance.

Melatonin Promotes Rice Seed Germination under Drought Stress by Regulating Antioxidant Capacity

Drought stress is a serious threat to the germination of plant seeds and the growth of seedlings. Melatonin has been proven to play an important role in alleviating plant stress. However, its effect on seed germination under drought conditions is still poorly understood. Therefore, we studied the effects of melatonin on rice seed germination and physiological characteristics under drought stress. Rice seeds were treated with different concentrations of melatonin (i.e., 0, 20, 100, and 500 μM) and drought stress was simulated with 5% polyethylene glycol 6000 (PEG6000). The results showed that 100 μM melatonin can effectively improve the germination potential, rate and index; the vigor index of rice seeds; and the length of the shoot and root. In addition, that treatment also increased the activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and reduced the content of malondialdehyde (MDA). The grey relational grade between the shoot MDA content and the melatonin seed-soaking treatment was the highest, which could be useful for evaluating the effect of melatonin on drought tolerance. Two-way analysis of variance showed that the effect of single melatonin treatment on rice seeds was more significant than that of single drought stress and interaction treatment of drought and melatonin (p < 0.05). The subordinate function results showed that 100 μM melatonin significantly improved the germination and physiological indexes of rice seeds and effectively alleviated the adverse effects of drought stress on rice seedlings. The results helped to improve the understanding of the morphological and physiological involvement of melatonin in promoting seed germination and seedling development under drought stress.

Novel Plant Growth Regulator Guvermectin from Plant Growth-Promoting Rhizobacteria Boosts Biomass and Grain Yield in Rice.

Food is a fundamental human right, and global food security is threatened by crop production. Plant growth regulators (PGRs) play an essential role in improving crop yield and quality, and this study reports on a novel PGR, termed guvermectin (GV), isolated from plant growth-promoting rhizobacteria, which can promote root and coleoptile growth, tillering, and early maturing in rice. GV is a nucleoside analogue like cytokinin (CK), but it was found that GV significantly promoted root and hypocotyl growth, which is different from the function of CK in Arabidopsis. The Arabidopsis CK receptor triple mutant ahk2-2 ahk3-3 cre1-12 still showed a GV response. Moreover, GV led different growth-promoting traits from auxin, gibberellin (GA), and brassinosteroid (BR) in Arabidopsis and rice. The results from a four-year field trial involving 28 rice varieties showed that seed-soaking treatment with GV increased the yields by 6.2 to 19.6%, outperforming the 4.0 to 10.8% for CK, 1.6 to 16.9% for BR, and 2.2 to 7.1% for GA-auxin-BR mixture. Transcriptome analysis demonstrated that GV induced different transcriptome patterns from CK, auxin, BR, and GA, and SAUR genes may regulate GV-mediated plant growth and development. This study suggests that GV represents a novel PGR with a unique signal perception and transduction pathway in plants.

Effects of Seed Soaking and Growing Media on Germination and Survivability of Acid Lime (Citrus aurantifolia Swingle)

Seed germination is the most important aspect for raising the nursery for successful seedling production of acid lime. The present study was carried out to explore the effect of different seed soaking treatment with growing media on seed germination and survivability of acid lime (Citrus aurantifolia Swingle) under net house condition. The experiments were laid out as a Completely Randomized Design with Factorial concept comprising twenty four treatment combinations with three replicates. The seeds of acid lime were treated with different seed soaking: water, GA3 @ 50 ppm, GA3 @ 100 ppm, cow urine @ 25%, cow urine @ 50% and cow dung slurry (1:1, cow dung:water w/w) and sowed in different growing media combinations: Sand + Vermicompost (1:1 v/v), Sand + Farmyard manure (1:1 v/v), Sand + Vermicompost + Cocopeat (1:1:1 v/v/v), Sand + Farmyard manure + Cocopeat (1:1:1 v/v/v). The result indicated that GA3 @ 100 ppm was found to be the most effective for better germination parameters, growth parameters and survival percentage of acid lime seedlings. Among the different growing media, Sand + Vermicompost + Cocopeat (1:1:1 v/v/v) recorded higher values for germination parameters, growth parameters and survival percentage of acid lime seedlings. The treatment combination of GA3 @ 100 ppm and Sand + Vermicompost + Cocopeat (1:1:1 v/v/v) showed better germination parameters, growth parameters and survival percentage. In conclusion, the combination of GA3 @ 100 ppm and Sand + Vermicompost + Cocopeat (1:1:1 v/v/v) was found most suitable for better growth of acid lime seedling.

Invigorasi Benih Terhadap Viabilitas dan Vigor Benih Kacang Tanah (Arachys Hypogaea)

Seed treatment or so called as seed invigoration is one of effort to increase seed germination (viability) and avoid the attack of disease. This study aimed to examine the effect of peanut seeds tretament using water and Ca(OH)2 solution on growth, viability, and vigor of peanut seeds, which were arranged in a Randomized Block Design consisting of five levels and three replications, namely, P0 (control), P1 (immersion in water temperature of 20-25oC), P2 (immersion with water temperature of 50oC), P3 (immersion with water temperature of 20-25oC + Ca(OH)2), and P4 (soaking with water 50oC + Ca(OH)2). The results showed that the seed soaking treatment significantly affected plant height, root length, germination and vigor index of peanut seeds. Soaking the seeds in water at a temperature of 20-25oC (P1) can give the highest of plant height, percentage of germination and vigor index of 84% and 75% higher, respectively, than without seed soaking treatment. However, the treatment of seed soaking by adding a solution of Ca(OH)2 was able to produce the highest primary root length.

Guvermectin, a novel plant growth regulator, can promote the growth and high temperature tolerance of maize.

Guvermectin is a recently discovered microbial N9-glucoside cytokinin compound extracted from Streptomyces sanjiangensis NEAU6. Although some research has reported that N9-glucoside cytokinin compounds do not have the activity of cytokinin, it has been noted that guvermectin can promote growth and antifungal activity in Arabidopsis. Maize is an important food crop in the world and exploring the effect of guvermectin on this crop could help its cultivation in regions with adverse environmental conditions such as a high temperature. Here, we investigated the effects of guvermectin seed soaking treatment on the growth of maize at the seedlings stage and its yield attributes with different temperature stresses. The maize (cv. Zhengdan 958) with guvermectin seed soaking treatment were in two systems: paper roll culture and field conditions. Guvermectin seed soaking treated plants had increased plant height, root length, and mesocotyl length at the seedlings stage, and spike weight at maturity in the field. But only root length was increased at the paper roll culture by guvermectin seed soaking treatment. Guvermectin seed soaking treatment reduced the adverse effects on maize seedling when grow at a high temperature. Further experiments showed that, in high temperature conditions, guvermectin treatment promoted the accumulation of heat shock protein (HSP) 17.0, HSP 17.4 and HSP 17.9 in maize roots. Comparative transcriptomic profiling showed there were 33 common differentially expressed genes (DEGs) in guvermectin treated plants under high temperature and room temperature conditions. The DEGs suggested that guvermectin treatment led to the differential modulation of several transcripts mainly related with plant defense, stress response, and terpenoid biosynthesis. Taken together, these results suggested that the guvermectin treatment promoted the growth and tolerance of high temperature stresses, possibly by activation of related pathways. These results show that guvermectin is a novel plant growth regulator and could be developed as an application to maize seeds to promote growth in high temperature environments.

Seed-Soaking with Melatonin for the Improvement of Seed Germination, Seedling Growth, and the Antioxidant Defense System under Flooding Stress

Flooding is the main cause of inhibited seed germination and seedling growth during the direct seeding of rice. As a growth-regulating hormone, melatonin plays an important role in promoting seed germination and enhancing plant stress resistance. However, there are still many unknown mechanisms related to the exogenous-melatonin-mediated regulation of submergence tolerance during seed germination. To overcome these challenges, this study investigated the effects of seed-soaking with different melatonin concentrations on the germination and physiological characteristics of rice seeds over different flooding times. The results showed that the exogenous administration of 100 μM of melatonin significantly improved the germination potential, germination rate, germination index, and vigor index of seeds and increased the size of the aboveground and underground biomass. By increasing the activities of superoxide dismutase (SOD) and peroxidase (POD) in shoots and roots, and reducing the content of malondialdehyde (MDA), the 100 μM melatonin alleviated the damage of rice seeds under flooding stress. The gray relational grade between the root MDA content and the melatonin seed-soaking treatment was the highest, and this was used to evaluate the effect of melatonin in alleviating flooding stress. A two-factor analysis of variance showed that the flooding stress treatment and the melatonin treatment had more significant effects on rice seed germination than the flooding and melatonin interaction treatments (p &lt; 0.01). The optimal number of days for rice seeds to resist flooding stress was two, and the optimal concentration for the melatonin seed-soaking treatment was 100 μM. In sum, a 100 μM melatonin seed-soaking treatment can effectively alleviate the damage of flooding stress on rice seeds and promote the growth and development of seedlings. This study provides the theoretical basis for a light and simple cultivation technique for the direct seeding of rice.

Melatonin-Induced Resilience Strategies against the Damaging Impacts of Drought Stress in Rice

Drought is a severe abiotic stress that imposes a serious threat to rice productivity. Although previous studies have found that melatonin can promote seed germination, the physiological regulation mechanism of drought tolerance in rice seed germination mediated by exogenous melatonin is still unclear. In order to overcome these challenges, polyethylene glycol 6000 (PEG6000) at concentrations of 20% and 35% was used to simulate osmotic stress. Rice seeds were treated with different concentrations of melatonin (i.e., 0, 20, 100, and 500 μM) to study the effects on germination characteristics, growth and development, superoxide dismutase (SOD) activity, peroxidase (POD) activity, catalase (CAT) activity, malondialdehyde (MDA) content, and soluble protein content. The results showed that the seed soaking treatment using melatonin at a concentration of 100 μM under drought stress effectively promoted the germination rate and improved the biomass of rice seed shoots and roots. Meanwhile, this treatment reduced MDA content to alleviate the oxidative damage of rice seeds caused by drought stress. The two-way ANOVA showed that the effect of single melatonin soaking treatment on rice seed germination was more significant than that of single drought stress and the interaction of drought stress and melatonin (p &lt; 0.05). Using the membership function method, it was shown that the critical gradient of rice seeds under drought stress was 35%, and the critical treatment of interactive treatment was 35% + 100 μM. Through grey correlation analysis, it was found that germination rate (7 d) had the highest grey correlation with melatonin seed soaking treatment to evaluate the mitigation effect of melatonin on drought stress. This study provides a theoretical basis for light and simple cultivation technology for the dry direct seeding of rice.

Exogenous Melatonin Activates Antioxidant Systems to Increase the Ability of Rice Seeds to Germinate under High Temperature Conditions.

High temperatures are a major concern that limit rice germination and plant growth. Although previous studies found that melatonin can promote seed germination, the physiological regulation mechanism by which exogenous melatonin mediates high temperature tolerance during rice seed germination is still largely unknown. In order to overcome these challenges, the present study investigates the effects of melatonin on the characteristics of rice seed germination as well as on antioxidant properties, under different high temperature conditions. The results show that 100 μM melatonin seed-soaking treatment under high temperature conditions effectively improves the germination potential, the germination index, and the vigor index of rice seeds; increases the length of the shoot and the root; improves the activity of the antioxidant enzymes; and significantly reduces the malondialdehyde content. The gray relational grade of the shoot peroxidase activity and the melatonin soaking treatment was the highest, which was used to evaluate the effect of melatonin on the heat tolerance of rice. The subordinate function method was used to comprehensively evaluate the tolerance, and the results show that the critical concentration of melatonin is 100 μM, and the critical interactive treatment is the germination at 38 °C and followed by the recovery at 26 °C for 1 day + 100 μM. In conclusion, 100 μM of melatonin concentration improved the heat resistance of rice seeds by enhancing the activity of the antioxidant enzymes.

The effect of potassium humate and micronutrients on the yield of cucumber fruits in greenhouse conditions

A hybrid Svyatogor F1 of Dutch breeding was grown in a winter greenhouse for three turns. Studies have shown that pre-sowing seed soaking treatment and foliar top dressing of plants with potassium humate did not affect germination, but positively affected plant growth, except for lithium carbon dioxide. For potassium humate and PABA, the leaf area increased, while for lithium it decreased. Micro fertilizers, except lithium, had a positive effect on the formation of fruits, their weight and yield. The largest yield of cucumbers was obtained by PABA and potassium humate mixed with other trace elements: 33.63 and 34.0 kg/m2 with a control indicator of 30.75 kg/m2. One foliage fertilization with micro fertilizers also had a positive effect: in terms of yield, the variant of a mixture of all fertilizers was in the first place - 34.75, the PABA with a yield of 33.93 kg/m2 was in the second place, and 30.97 kg/m2 were in the control. Lithium had a retarding effect on all indicators.

Effect of Concentration and Period of Seed Soaking with Atonik on Some Quantitative Traits of Mung Bean

A field experiment was carried out during spring season of 2016 and 2017 in the field of the Department of Field Crops - College of Agriculture - University of Anbar (Alternative Site – Abu Ghraib), to study the effect of concentration and Period of seed soaking with the Atonik growth regulator on the some quantitative traits of the mung bean (Al-Khadhrawi variety). Split plots arrangement according to randomized complete block design (RCBD) at three replications was used. The concentrations of soaking with Atonik (0, 2.5, 5- and 7.5-ml L-1) were the main plots, while the soaking period (0, 2, 4 and 6 hours) occupied the sub plots. The results showed that the seeds soaking with Atonik growth regulator at a 7.5 ml L-1 recorded the highest plant height (54.05 and 47.10 cm), number of pods (15.83 and 11.58 pods plant-1) and number of seeds (10.81 and 8.48 seeds pod-1) for both seasons respectively, and number of branches (14.33 branch plant-1) in the first season only. The soaking period for 6 hours was significantly superior and gave the highest plant height (54.23 and 46.59 cm), number of branches (14.00 and 12.80 plant branch- 1), number of pods (16.75 and 14.08 pod plant-1) and number of seeds (10.80 and 8.80 seed pod-1) for both seasons respectively. The interaction between concentrations of soaking at 7.5 ml L-1 and soaking period for 6 hours had highest values for more the studied traits and both seasons. We can bw conclude that the quantitative characteristics of the mung It can be improved by using seed soaking treatment before planting with Atonik growth regulator.

Study of the effectiveness of hydrogen peroxide in improving the germination characteristics of maize seed under water stress

"A factorial experiment was carried out in the lab. college of Agricultural Engineering Science, University of Baghdad Al- Jadiriyah during year of 2017 With the aim of improving the germination properties of Maize variety of Noor under water stress. According to the Completely randomize design (CRD) with three replications were used in both and two factors: first: it included water tensile treatments by exposing the seeds to a solution of polyethylene glycol PEG 6000 with three levels (0, -4 ,-8) Bar, while the second factor with three concentrations of the compound peroxide Hydrogen H2O2 with a concentration of 50% (0, 10 , 20 mg L-1). The results showed that water stress had a significant effect on the characteristics of Maize seedlings, as it reduced the level of water stress (-8) bar, the average germination percentage, Average 80.00%, Root Shoot length, 7.900 , 5.22 (cm), respectively, seedling dry weight 269.9 (mg seedlings-1) and Seed vigor index of drought resistance 0.781,while treatment with compound hydrogen peroxide H2O2 contributed to improving the characteristics of Maize seedlings significantly, as the seed soaking treatment at a concentration of 20 (mg L-1) recorded the highest germination rate of 89.44%, the feather length of 5.90 (cm), and the seedling dry weight 353.6 (mg seedlings-1). Germination and vigor index of drought resistant 1.089. We recommend to soak maize seeds with peroxide Hydrogen H2O2 (10 ) mg L-1 for 24 h before planting, especially under water stress."