Application of WOA–SVR in Seed Vigor of High-Voltage Electric Field Treatment on Aged Cotton (Gossypium spp.) Seeds

When seeds are treated with a high-voltage electric field (HVEF) to improve seed vigor, due to the large differences in the biological electromagnetic effects on different types of seeds, the methods of variance analysis and regression analysis based on data statistics are generally used to construct the optimal electric field dose prediction model; however, the generalization performance of the prediction model tends to be poor. To solve this problem, the electric intensity, frequency and treatment time were taken as the input variables for hybrid support vector regression (SVR) analysis to establish the prediction model of the seed comprehensive germination index. The whale optimization algorithm (WOA) was used to optimize the kernel parameters of the SVR. The optimized hybrid WOA–SVR model predicted the optimal comprehensive germination index of aged cotton (Gossypium spp.) seeds to be 329, the optimal HVEF dosage was 3.64 kV/cm × 99 s, and the frequency was 1.4 Hz. The aged cotton seeds were treated with the optimal HVEF and the germination test was carried out. Compared with the check (CK), the comprehensive germination index of seeds increased by 48%. The research results provided a new method and new idea for the optimal design of parameters for seed treatment with HVEF.

Germination and Seedling Parameters of Wheat as Affected by Storage Conditions

A storage experiment was carried out from 27th April to 27thDecember, 2019 to study the effect of storage conditions i.e. methods (open air, under sunshade and in stores), packages type (normal, gunny, polyethylene and metal containers) and periods of seeds fumigation with phosphine (15, 30 and 45 days) on germination and seedling parameters of wheat. The experiment was arranged in a factorial experiment in randomized complete block design (R.C.B.D.) with four replications. Stored wheat seeds under sunshade produced the highest values of final germination percentage, germination index, mean germination time, plumule length, radical length, seedling vigor index and seedlings dry weight, followed by stored wheat seeds in stores. The highest germination index, mean germination time, plumule and radical lengths, seedling vigor index and seedlings dry weight were recorded in the samples of wheat seeds sealed stored in metal containers, followed by normal stored in gunny packages. The highest percentage of final germination was obtained by normal stored in gunny packages, followed by sealing storage in metal containers. The highest final germination percentage, germination index, mean germination time, plumule length, radical length, seedling vigor index and seedlings dry weight and the lowest abnormal seedlings percentage, rotten and sold seeds percentages, speed germination index, co-efficient of germination and germination energy percentage were recorded when treated with phosphine at the rate of 3 tablets/m3after 15 days from beginning the storage. This study recommended that stored wheat seeds under sunshade in metal packages and treating with phosphine at the rate of 3 tablets/m3 after 15 days from beginning the storage to enhance germination and seedlings parameter of wheat under the environmental conditions of Dakahlia Governorate, Egypt.

Biosurfactant and chemical surfactant effectiveness test for oil spills treatment in a saline environment

Toxic and persistent nature of hydrocarbon and its products make it a significant concern for treating oil spills. In addition, hydrocarbons such as crude oil have long and complex carbon chains, making them challenging to remove directly. Emergency response for oil spills generally conducted by spraying dispersant agent into spillage surface. However, the use of chemical dispersants is reported to have a negative impact on the environment. Therefore, an environmentally friendly method for treating oil spills, utilizing biological agents such as biosurfactant or bioemulsifier, is needed. This research focuses on performance tests of more environmentally friendly surfactants as substitute for chemical surfactant which causes toxic effect when used. Surfactant performance was evaluated through three indicators: emulsifying index, dispersion effectiveness, and germination index (G.I.). Performance test was carried out for three types of surfactants: sophorolipid biosurfactant, methyl ester sulfonate (MES), and tween-80. Dispersion effectiveness test showed sophorolipid, MES, and tween-80 enhanced hydrocarbons dispersion in saline water up to 26.59, 38.65, and 48.19%, respectively. Germination index test showed the average G.I. for oil dispersed by sophorolipid, MES, and tween-80 are 153.16%, 143.94%, and 6.69 %, respectively. Research result suggests sophorolipid and MES have the properties to enhance oil dispersion under-examined laboratory conditions.

Non-chemical treatments to improve the seeds germination and plantlets growth of sessile oak

The current study aimed to investigate the effect of different treatments applied to sessile oak seeds in order to improve the germination features, development and growth of seedlings. The seeds were subjected to electric field, electromagnetic field and γ rays’ treatments. For the electric field study three distinct voltages (10V, 30V and 50V) and three values of exposure time (15 min., 35 min. and 60 min.) were considered. Displaying the seeds in an electric field for 60 minutes increased the germination rate with 58.89%. The highest value for the seedling’s height was obtained when seeds were exposed for 15 minutes at an intensity of 30V. The interaction between the intensity and the timing showed that treating seeds with 30V for 35 minutes improved significantly the seedlings peculiarities. In regard to the electromagnetic field, the seeds were subjected to a single value of electromagnetic field (B=0,4mT; i=0,680 A) and three values of exposure time: 10 min., 20 min. and 30 min. The sessile oak seeds subjected to the electromagnetic field for 20 minutes induced the highest value of germination percentage (90.00%) and germination index (1.81) and those seeds produced plantlets with high diameter (2.69 mm) and with significant differences towards non-treated plants. For γ rays treatments a dosage of 2 Gy induced the highest value of germination percentage (86.67%), of germination index (2.02); of germination energy (7.7); and of germination speed (7.24). A dosage of 6 Gy decreased the values of the same parameters. Our results showed that a dosage of 2 Gy improved also the growth parameters such as plantlets diameter (2.65 mm) and height (11.25 cm). In short, the physical treatments represent an ecological substitute approach towards the chemical substances presently used to improve seeds germination. Using physical treatments for seeds germination and growth of seedlings might be a harmless alternative for environment.

Effects of osmo-priming on germination, growth and green pod yield of okra [Abelmoschus esculentus (L.) Moench] at Luyengo, Middleveld of Eswatini

Okra is a nutritious summer vegetable crop in Eswatini. However, it has slow and uneven germination. Seed pre-sowing treatment through osmo-priming can enhance the germination, growth and yield of okra. Thus, laboratory and field experiments were conducted at Luyengo, Middleveld of Eswatini in 2019/2020 cropping season to determine the effect of osmo-priming on germination, growth and yield of okra. Treatments included priming of seeds with Polyethylene glycol (PEG) concentration of 5%, 10%, 15%, and 20% and unprimed control. Completely randomized design was used for the laboratory experiment and randomized complete block design was used for the field experiment. Results showed significant (p<0.01) effect of seed priming on the germination index, mean germination time and final germination percentage of okra seeds. Significantly the highest germination index (5.2) and final germination percentage (66) were recorded in priming with 15% PEG. Similarly, seeds priming with 15% PEG resulted in significantly the highest number of leaves per plant (12.07), leaf area index (1.49), canopy height (120.9 cm), and number of branches per plant (8.13). Moreover, okra seeds primed in 15% PEG resulted in the highest pod length and total green pod yield (2009.8 kg ha-1). Thus, it can be concluded that seed priming with 15% PEG is the most effective in improving the germination, growth and yield of okra in the study area.

Biostimulant Effects of Cerium on Seed Germination and Initial Growth of Tomato Seedlings

The rare earth element (REE) cerium (Ce) can act as a biostimulant in diverse crop plants. The effects of 0, 5, 10, and 15 µM Ce (supplied as CeCl3 7H2O) on seed germination and the initial growth of tomato (Solanum lycopersicum L.) cv. Vengador were evaluated. After a 12 h imbibition, the weight of the seeds treated with 15 µM Ce was 37.5% greater than that observed in the control. The germination index of the seeds treated with 5 µM Ce was greater than 100% (101.93%), though when applying 10 µM Ce this index was 17.53% lower than the control seeds. Nevertheless, Ce treatments did not significantly affect the coefficient of velocity of germination, relative seed germination, germination index, radicle length, dry biomass, or relative growth. Interestingly, shoot length increased significantly in the treatments with 5, 10, and 15 µM Ce. This tendency was also observed in the dry biomass weight and relative growth of the shoots. Hence, Ce has a stimulating effect on germination and initial growth in tomato cv. Vengador shoots. In particular, there was a priming effect of Ce on seeds, reflected in a higher weight gain in Ce-treated seeds, which indicated greater water absorption. Therefore, Ce can be an alternative to accelerate the production time of tomato seedlings in seedbeds.

The GmXTH1 Gene Improves Drought Stress Resistance of Soybean Seedlings

To study the role of GmXTH1 gene in alleviating drought stress. T4 transgenic soybean seeds with GmXTH1 gene were treated with PEG6000 at 0%, 5%, 10% and 15%, respectively. Germination potential, germination rate and germination index were measured. The results showed that the germination potential, germination rate and germination index of OEA1 and OEA2 strains overexpressed in T4 generation were significantly higher than that of control material M18. After 0d, 7d and 15d drought stress, the analysis of seedling phenotypes and root-shoot of different T4 generation transgenic soybean lines showed that under stress conditions, the growth of GmXTH1 overexpression material was generally better than that of control material M18, and the growth of GmXTH1 interference expression material was generally worse than that of control material M18, with significant differences in plant phenotypes.The root system of GmXTH1 overexpressed material was significantly developed compared with that of control material M18. The analysis of physiological and biochemical indexes showed that the relative water content and the activity of antioxidant enzymes (superoxide dismutase and peroxidase) of GmXTH1 transgenic soybean material were significantly higher than that of control material M18, and the accumulation of malondialdehyde was lower under the same stress conditions at seedling stage. Fluorescence quantitative PCR assay showed that the relative expression of GmXTH1 gene in transgenic soybean was significantly increased after drought stress.The results showed that the overexpression of GmXTH1 could increase the total root length, surface area, total projection area, root volume, average diameter, total cross number and total root tip number, thereby increasing the water intake and reducing the transpiration of water content in leaves, thus reducing the accumulation of MDA and producing more protective enzymes in a more effective and prompt way.Reducing cell membrane damage to improve drought resistance of soybean.

A, The Allelopathic effects of Papavare somniferum on germination and initial seedling growth of Echinochloa cruss-galli

Weeds are unwanted plants in crop that can be control by different methods among them use of aqueous extract of crop is an imperative method. To investigate the allopathic potential of aqueous extract of winter crop Papavare somniferum (opium) on summer weed Echinochloa cruss-galli (barnyard grass) laboratory experiments were conducted. The experiment coomprised seven concentrations (0, 0.25, 0.50, 1, 2, 4, and 8%) of different plant parts i.e., leaves, stem and flower of P. somniferumwere. All the tested concentrations and plant parts of P. somniferum significantly reduced mean emergence time, germination index, germination percentage, time to 50% germination as well as well growth of E. cruss-galliweed. However, maximum mean emergence time (9.07 days), time to 50% germination (3.67 days) was noted at leaves and stem extract, respectively. Application of aqueous extract of stem at 8% concentration resulted in greatest time to complete 50% germination (5.42 days) and lowest fresh weight (6.28 g), dry weight (1.00 g) and root length (0.33 cm) of E. cruss-galli. Whereas leaf extract at 8% concentration produces less shoot length (1.13 cm) and more emergence time (9.18 days). Lowest emergence percentage (6.67%) and germination index (0.89) were produced by aqueous extract of fruit at 8% concentration. On the basis of this experiment, it can be concluded that higher concentration (8%) of stem extract of P. somniferumwas used to biologically control the infestation of E. cruss-galli weed.

THE ALLELOPATHICITY OF RED SPRANGLETOP (Leptochloa chinensis L.) AGAINST GERMINATION AND SEEDLING GROWTH OF RICE (Oryza sativa L.)

Red sprangletop (Leptochloa chinensis L.) is a problematic weed of aerobic rice (Oryza sativa L.) that greatly reduces in yield. The laboratory studies were undertaken to confirm allelopathicity of its plant leachates and soil-decomposition plant residues towards emergence and seedling growth of rice. In first experiment, aqueous extracts from various plant parts of red sprangletop (stem, root, leaves, flower and entire plant) at their 5% (w/v) concentration were applied to germinating rice seeds. In second experiment, soil-decomposed red sprangletop plant residues of variable concentrations (2, 4 and 6% w/w) were used as germination media for rice. Among plant parts, red sprangletop leaves showed maximum allelopathic effect by fully inhibiting the germination of rice while its stem could be positioned at second situation as it caused 60, 73, 84.13 and 86 % reductions in germination percentage, germination index, seedling length and seedling dry biomass of rice as compared with control, respectively. This treatment also resulted in maximum delays in mean germination time (up to 4.80 days) and days taken to 50% germination (up to 4.40 days) of rice. The highest concentrated (6%) soil-decomposed plant residue of red sprangletop significantly diminished the germination percentage, germination index, seedling length and seedling vigor index that were 35.13, 23.26 and 41.61% lower than control. It very well may be presumed that liquid concentrates of leave and stem soil-decomposed plant residues of 6% concentration had different kind of allelochemicals that inhibited the germination, seedling growth and development of rice.

Thermo-Chemical Treatment for Carcass Disposal and the Application of Treated Carcass as Compost

A mechanized thermo-chemical treatment system was developed to treat the undecomposed carcass and remediate livestock burial sites. Animal carcasses were thus processed via crushing, mixing, and treatment with quicklime treatment, heat treatment (200–500 °C), and mixing with sawdust. The machinery was applied to two sites where 16,000 chickens and 418 pigs had previously been buried in fiber-reinforced plastic storage bins. No dioxins were detected in the gas discharged during processing, and the concentration of total volatile organic compound, toluene, ethylbenzene, xylene, and styrene were 430.3, 139.0, 18.3, 21.4, and 10.4 μg/m3, respectively, which were below the air pollutant emission standards issued by the Korean Ministry of Environment. Korean standards stipulating the use of treated carcasses as compost (C, N, and P content, heavy metal concentration, Escherichia coli, and Salmonella) were met, but the germination index value was less than 70, not satisfying the criteria. Plant height, leaf length, leaf width, and dry weight of lettuce grown in soil amended with treated carcass product were significantly lower than those grown in low nutrient soil due to the poor germination index of the treated carcass. These results indicate that a composting process is required before the use of the treated carcass as a fertilizer. The addition of zeolite retarded the elution of ammonia from the carcasses and its efficiency was about 87.9%. It is expected that the mechanized thermo-chemical treatment process developed in this study could replace other technologies for the remediation of livestock burial sites.