Seed Priming Research Articles

Effective Priming Techniques to Enhance Ghaf (Prosopis cineraria L. Druce) Seed Germination for Mass Planting

Seed priming is a cost-effective and efficient pre-sowing technique that promotes seed germination and plant growth under abiotic stress. This study was conducted to investigate the effect of different priming treatments on breaking the dormancy of ghaf (Prosopis cineraria L. Druce) seeds. Furthermore, the effects of storage conditions and seed coating on seed germination were examined. Treatments with hot water, KNO3, KCl, polyethylene glycol (PEG), H2SO4, gibberellin (GA3), cytokinin benzyl adenine (BA), and H2SO4 + BA were investigated. Among all the tested treatments, seeds responded the best to the H2SO4 50% 2 min + BA (200 ppm) priming treatment in terms of germination uniformity and effectiveness. This treatment initiated germination 5 days after sowing and increased the germination percentage from 11.32% in the untreated seed to 83% and 100% in the primed ones after 5 and 20 days, respectively. The germination percentage and primary root length were shown to be more responsive to this combined treatment, followed by the H2SO4 50% 2 min+ BA 100 ppm. This treatment achieved the best result of 100% germination when the seeds were covered in a seed ball. Additionally, the treated seeds could be stored at room temperature or 4 °C for more than 10 days with no negative effect on the germination. Based on these findings, this treatment could be recommended to farmers and plant producers to boost the mass production of ghaf trees.

Magnesium oxide nanoparticles improved vegetative growth and enhanced productivity, biochemical potency and storage stability of harvested mustard seeds

A field study was conducted to investigate the influence of MgO-NPs priming on growth and development of mustard. Priming of mustard seeds before sowing with MgO-NPs at concentration 10, 50, 100, and 150 μg/ml enhanced the vegetative parameters of plants, with considerable increase in leaf area. MgO-NPs exposure increased the photosynthetic pigment accumulation in mustard that led to increase in biomass, carbohydrate content, and the yield in terms of total grain yield. Increased chlorophyll has simultaneously increased the oxidative stress in plants, and hence stimulated their antioxidant potential. A consistent increase was observed in the content of mustard polyphenols and activity of SOD, CAT, and APX on MgO-NPs exposure. MgO-NPs induced oxidative stress further reduced the protein content and bioavailability in mustard. We further, evaluated the influence of MgO-NPs on the quality of mustard harvested seeds. The seeds harvested from nanoprimed mustard possessed increased antioxidant potential and reduced oxidative stress. The carbohydrate and protein accumulation was significantly enhanced in response to nanopriming. Reduced chlorophyll content in seeds obtained from nanoprimed mustard indicated their potential for disease resistance and stability on long term storage. Therefore, the seeds harvested from MgO-NPs primed mustard were biochemically rich and more stable. Therefore, MgO-NPs priming can be potentially used as a novel strategy for growth promotion in plants where leaves are economically important and a strategy to enhance the seed quality under long term storage conditions.

Effect of Abiotic Stresses from Drought, Temperature, and Density on Germination and Seedling Growth of Barley (Hordeum vulgare L.).

Seed germination and seedling growth are highly sensitive to deficit moisture and temperature stress. This study was designed to investigate barley (Hordeum vulgare L.) seeds' germination and seedling growth under conditions of abiotic stresses. Constant temperature levels of 5, 10, 15, 20, 25, 30, and 35 °C were used for the germination test. Drought and waterlogging stresses using 30 different water levels were examined using two methods: either based at 1 milliliter intervals or, on the other hand, as percentages of thousand kernel weight (TKW). Seedling density in a petri dish and antifungal application techniques were also investigated. Temperature significantly impacted germination time and seedling development with an ideal range of 15-20 °C, with a more comprehensive range to 10 °C. Higher temperatures reversely affected germination percentage, and the lower ones affected the germination and seedling growth rate. Germination commenced at 130% water of the TKW, and the ideal water range for seedling development was greater and more extensive than the range for germination, which means there is a difference between the starting point for germination and the seedling development. Seed size define germination water requirements and provides an objective and more precise basis suggesting an optimal range supply of 720% and 1080% of TKW for barley seedling development. A total of 10 seeds per 9 cm petri dish may be preferable over greater densities. The techniques of priming seeds with an antifungal solution (Bordóilé or Hypo) or antifungal application at even 5 ppm in the media significantly prevented fungal growth. This study is novel regarding the levels and types of abiotic stresses, the crop, the experimental and measurement techniques, and in comparison to the previous studies.

Chitosan Nanoparticles as Seed Priming Agents to Alleviate Salinity Stress in Rice (Oryza sativa L.) Seedlings

Nanoparticle-based seed priming has opened new avenues in crop science due to their plant growth promoting potential. Similarly, biopolymers such as chitosan (CS) are widely studied as seed priming agents due to the biodegradable and biocompatible nature, ability to enhance germination percentage and overall seedling health. Therefore, priming with chitosan nanoparticles (CNPs) is a promising tool to enhance overall plant health. Here, we studied the effect of nanopriming with CNPs or CS (50 µg/mL) on morphological, physiological, and biochemical parameters of rice seedlings, grown in salinity stress conditions NaCl (0–250 mM). CNPs were synthesized using an ionic gelation method and characterized by scanning electron microscopy (50–100 nm), zeta potential analyser (Particle size distribution–373.5 ± 3.7 nm; polydispersity index- > 0.4; zeta potential–45.3 ± 2.5 mV) and profilometry (300–1500 nm hydrodynamic height). Morphological, physiological, and biochemical responses of rice seedlings grown from seeds primed with either CNPs or CS showed a positive effect on germination, seedling vigour, biochemical and antioxidant responses. Seeds primed with CNPs and CS demonstrated significantly higher germination potential and seedling vigour compared to control hydro-primed seeds when grown under increasing NaCl concentrations. These outcomes highlight that CNPs and CS can be used as potential seed priming agents to alleviate salinity stress in rice seedlings. However, further studies are warranted to understand the effect of CNPs and CS seed priming on the overall growth and development of rice plants as well as rice yield.

Mitigation of salt stress and stimulation of growth by salicylic acid and calcium chloride seed priming in two barley species

The main objective of the current study is to underline the effects of salicylic acid or calcium chloride seed priming on plant growth, water content, chlorophyll content and photosynthetic activity of two barley species Hordeum marinum and Hordeum vulgare exposed to salinity (0, 100 and 200 mM NaCl). Results revealed that salinity decreased shoot and root growth, transpiration rate, chlorophyll concentration, stomata conductivity and water content in plants obtained from unprimed seeds. This reduction was dependent on the saline concentration used. However, Hordeum marinum species showed tolerance by maintaining tissue hydration, growth, photosynthetic assimilation and chlorophyll biosynthesis in stressed plants compared to controls. Moreover, priming seeds with salicylic acid or calcium chloride significantly improved all the above parameters under different salt treatments, suggesting that the effectiveness of this approach mainly depends on the priming agent applied and may vary with species and stress intensity applied.

The chances in the redox priming of nondormant recalcitrant seeds by spermidine.

The problems posed by seed sensitivity to desiccation and aging have motivated the development of various techniques for mitigating their detrimental effects. The redox priming of seeds in antioxidant solution to improve their postharvest performance is one of the approaches. Spermidine (Spd) was tested as an invigorating solution on nondormant recalcitrant (desiccation sensitive) seeds of the silver maple (Acer saccharinum L.). The treatment resulted in an 8-10% increase in germination capacity in seeds subjected to mild and severe desiccation, while in aged seeds stored for six months, no significant change was observed. The cellular redox milieu, genetic stability, mitochondrial structure and function were investigated to provide information about the cellular targets of Spd activity. Spd improved the antioxidative capacity, especially the activity of catalase, and cellular membrane stability, protected genome integrity from oxidative damage and increased the efficiency of mitochondria. However, it also elicited a hydrogen peroxide burst. Therefore, it seems that redox priming in nondormant seeds that are highly sensitive to desiccation, although positively affected desiccated seed performance, may not be a simple solution to reinvigorate stored seeds with a low-efficiency antioxidant system.

Influence of priming treatments on seed germination and growth characteristics of Moringa oleifera seedlings under laboratory and greenhouse conditions

Seed priming is the treatment of seeds with various priming substances to improve germination and seedling quality, and plant growth. The procedure entails advancing the seed to an equivalent stage of the germination process to achieve rapid and uniform emergence when planted, which is required in the case of Moringa oleifera to reduce the damage of ageing seeds, stimulate their performance, and overcome uneven germination rate due to seedcoat hardening, that leads to wide variation in terms of commercial qualities in the planting field. Therefore, a series of seed priming experiments were conducted to determine the optimal methods of priming treatments that maximise Moringa oleifera total germination, germination rate, and seedling vigour. Moringa oleifera seeds were treated with hydropriming, osmopriming (KNO3), and nutripriming (SeedActivator) for 4, 8, and 12 hrs. Germinability was improved by priming treatments. Results indicated that the highest germination percentage was recorded on seeds subjected to hydropriming (63.25%), followed by nutripriming (61.75%) and osmopriming (60%) with the exact duration of 4 hrs soaking time. All pre-germination treatments have significantly early mean germination days (MGT) compared to the unprimed seeds. In the seed pouch study, seeds treated with hydropriming for 4 hrs had shown the best results to improve roots growth in total root length (cm), root volume (cm3 ), the number of forks, and the number of crossings with 240.52 cm vs. 163.64 cm, 0.47 cm3 vs. 0.29 cm3 , 517.80 vs. 271.47 and 59.20 vs. 28.53 respectively when compared to unprimed seeds. The positive effect of priming can also be seen in the seedling growth of M. oleifera grown in a pot with two different growing media.

Response of selected nutrient elements in pea (Pisum sativum L.) leaf tissues to the seed priming-and-drying technology in cucurbitacin phytonematicides

Priming-and-drying technology for pea (Pisum sativum L.) seeds with hypogeal germination showed that the technology could improve plant growth and development, while suppressing nematode population densities, but without information on the potential causal factors for the former. A study was, therefore, conducted in Limpopo Province, South Africa, to investigate the extent to which plant responses could be associated with accumulation of foliar nutrient elements in pea plants post-subjecting pea seeds to the technology. After a 2-h priming of pea seeds in geometric concentration of Nemarioc-AL and Nemafric-BL phytonematicides and then air-dried in ovens at 26ºC for 72 h. Seeds were sown in 20-cm-diameter plastic pots filled with appropriate growing mixture, with one trial in the greenhouse and the other on microplots. At 60 days after sowing, 10 healthy mature leaves per plant were prepared for extraction of nutrient elements through the digestion method and then quantified in Atomic Absorption Spectrophotometer ICPE-9000. Iron, Na, K and Zn in leaf tissues of pea plants versus increasing phytonematicides concentration, regardless of the growing condition, exhibited significant (P ≤ 0.05) negative or positive quadratic equations. In conclusion, results suggested that the priming-and-drying technology could affect pea plant growth through disproportionate accumulation of nutrient elements in foliar leaf tissues.

Interactive effects of melatonin and salicylic acid on Brassica napus under drought condition

It is imperative to understand the synergetic actions of Melatonin (MET) and salicylic acid (SA) in counteracting drought stress. A pot experiment was performed to investigate the interactive effects of exogenously applied MET and SA on morphology, physiology, and biochemical characteristics of drought-stressed canola (Brassica napus). Two cultivars (Super canola and Faisal canola) were used. MET (0.1 µM) and SA (0.50 mM) were applied as seed priming and foliar spray. Plants were exposed to severe drought (45% field capacity) at the reproductive stage. Drought stress caused a significant reduction in shoot length (19%), plant fresh (15%) and dry (17%) biomass, yield (30%), photosynthetic rate (43%), water potential (29%) and osmotic potential (33%) values. Increased activity of free amino acids (20%), total soluble sugars (5%), and different antioxidant enzymes like catalase (27%), peroxidase (23%), superoxide dismutase (20%) and ascorbate peroxidase (35%), were recorded under drought. Seed priming and foliar application of MET and SA reduced the negativity of drought. Priming of seeds with MET, as well as synergetic application of MET priming and SA foliar spray, were the most effective treatments, showing the most significant growth criteria (22% increase in plant height, 46% in fresh and 40% in dry biomass), yield components (49%), water (54%) and osmotic potential (28%), and endogenous MET (17%) and SA (16%) content. Super canola cultivar showed better growth than Faisal canola. Study showed that the synergetic application of MET and SA has the potential to induce stress resistance and enhance canola plants' growth under drought.

Effect of Seed Priming with Chitosan Hydrolysate on Lettuce (Lactuca sativa) Growth Parameters.

Seed priming increases germination, yield, and resistance to abiotic factors and phytopathogens. Chitosan is considered an ecofriendly growth stimulant and crop protection agent. Chitosan hydrolysate (CH) is an unfractionated product of hydrolysis of high-molecular-weight crab shell chitosan with a molecular weight of 1040 kDa and a degree of deacetylation of 85% with nitric acid. The average molecular weight of the main fraction in CH was 39 kDa. Lettuce seeds were soaked in 0.01-1 mg/mL CH for 6 h before sowing. The effects of CH on seed germination, plant morphology, and biochemical indicators at different growth stages were evaluated. Under the 0.1 mg/mL CH treatment, earlier seed germination was detected compared to the control. Increased root branching was observed, along with 100% and 67% increases in fresh weight (FW) at the 24th and 38th days after sowing (DAS), respectively. An increase in the shoot FW was found in CH-treated plants (33% and 4% at the 24th and 38th DAS, respectively). Significant increases in chlorophyll and carotenoid content compared to the control were observed at the 10th DAS. There were no significant differences in the activity of phenylalanine ammonia-lyase, polyphenol oxidase, β-1,3-glucanase, and chitinase at the 24th and 38th DAS. Seed priming with CH could increase the yield and uniformity of plants within the group. This effect is important for commercial vegetable production.

CuO Nanoparticle-Mediated Seed Priming Improves Physio-Biochemical and Enzymatic Activities of Brassica juncea.

The use of nanoparticles (NPs) in agricultural fields has risen to a level where people are considering NPs as an alternative to commercial fertilizers. The input of copper oxide NPs (CuO NPs) as seed primers was investigated in this study, and the growth indices of Brassica juncea such as phenotypic parameters, photosynthetic attributes, and biochemical parameters were measured during maximum vegetative growth stage, i.e., at 45 days after sowing. Surface sterilized seeds were soaked in varying concentrations (0, 2, 4, 8 and 16 mg/L) of CuO NPs for 15, 30, and/or 45 min. After those priming periods, the seeds were planted in pots and allowed to grow naturally. Among the different tested concentrations of CuO NPs, 4 mg/L of CuO NPs for 30 min seed priming proved to be best, and considerably increased the, shoot length (30%), root length (27%), net photosynthetic rate (30%), internal CO2 concentration (28%), and proline content (41%). Besides, the performance of the antioxidant enzymes, viz, superoxide dismutase, catalase, peroxidase, and biochemical parameters such as nitrate reductase and carbonic anhydrase were also increased by several folds after the application of CuO NPs in B. juncea. The present study suggests that CuO NPs can be effectively used to increase the performance of B. juncea and may also be suitable for testing on other crop species.

Optimization of 'on farm' hydropriming conditions in wheat: Soaking time and water volume have interactive effects on seed performance.

Seed priming is a simple and cost effective method to obtain a better plant stand under diverse environmental conditions. The current study was designed to determine the optimal priming duration and water volume for wheat seed. For this experiment, three wheat genotypes with distinct genetic and adaptive backgrounds were chosen. Seeds of each genotype were hydroprimed for 7 durations, i.e. 1, 2, 4, 8, 12, 16, and 20 hours, in three different water volumes, i.e. half, equal, and double volume with respect to seed weight and then surface dried for 1 hour. The control was unprimed (dry) seed. The germination characteristics and seedling vigour potential of hydroprimed seeds were evaluated in the lab by recording several parameters such as germination percentage and speed, seedling growth, and vigour indices at two different temperature levels. The results showed that optimal duration for hydropriming of wheat seed is 12 hours with an equal volume with respect to original seed weight, closely followed by 8 hours with double volume. Reduction in seed performance was observed at 16 and 20 hours priming particularly at double volume treatment. Effect of temperature on seed germination showed improvement in seedling vigour at 25°C when compared to 20°C, although effect on germination percentage was non-significant. Volume of water and priming duration showed significant interactive effects demonstrating that a higher volume can give equivalent results at a shorter duration and vice versa. Another experiment was also conducted to compare the on-farm priming (surface dried seed) with conventional priming (seed re-dried to original moisture) taking 3 potential durations i.e. 8, 12 and 16 hours. Results revealed that both priming methods were statistically at par in terms of germination percentage, while, surface drying resulted in better seedling vigour and speed of germination.

Effect of Seed Priming Methods on Seed Quality of Okra (Abelmoschus esculentus (L.) Moench) Genotypes

Seed priming is an effective way of promoting seed germination and vigor of okra by alleviating seed dormancy in fresh or stored okra seeds. An experiment was carried out to evaluate the effect of seed priming treatment on seed physiological quality of okra genotypes. This experiment was conducted in a laboratory at Haramaya University in a completely randomized design with 4 replications. It comprised of 5 seed priming treatments (untreated seeds, tape water, 200 ppm GA3, 0.5% KH2PO4, and 50% cow urine) and 5 okra genotypes (Clemson, Arka Anamika, SOH701, 240207, and 240586). The results showed that the main and interaction effects of seed priming treatment and genotypes significantly affected physiological seed quality attributes and hard seed percentage. GA3-treated genotype Clemson showed the highest germination (78.28%) and germination speed (25.29). Similarly, GA3-treated genotypes SHO701 and 240586 had the highest seed vigor index I (13.161) and vigor index II (34.14), respectively. There were no hard seeds in genotype Clemson treated with GA3 and cow urine, genotype SOH701 treated with GA3, besides genotype 240207 treated with KH2PO4 and tap water. All seed priming treatments had a significant positive effect on physiological quality and seed overcame seed hardness in all 5 okra genotypes compared to controls. Therefore, in this study concluded that GA3 seed priming treatment improved physiological seed quality, and alleviated seeds hardness in okra genotypes. As an alternative to GA3 seed priming treatments, Ethiopian farmers can also use tape water, cow urine, and KH2PO4 seed priming treatments.

The comparative effects of manganese nanoparticles and their counterparts (bulk and ionic) in Artemisia annua plants via seed priming and foliar application.

The world has experienced an unprecedented boom in nanotechnology. Nanoparticles (NPs) are likely to act as biostimulants in various plants due to having high surface/volume value. However, understanding the actual effect of NPs is essential to discriminate them from other counterparts in terms of being applicable, safe and cost-effective. This study aimed to assay the impact of manganese(III) oxide (Mn2O3)-NPs via seed-priming (SP) and a combination of SP and foliar application (SP+F) on Artemisia. annua performance at several times intervals and comparison with other available manganese (Mn) forms. Our findings indicate that SP with MnSO4 and Mn2O3-NPs stimulates the processes that occur prior to germination and thus reduces the time for radicle emergence. In both applications (i.e., SP and +F), none of the Mn treatments did show adverse phytotoxic on A. annua growth at morpho-physio and biochemical levels except for Mn2O3, which delayed germination and further plant growth, subsequently. Besides, from physio-biochemical data, it can be inferred that the general mechanism mode of action of Mn is mainly attributed to induce the photosynthetic processes, stimulate the superoxide dismutase (SOD) activity, and up-regulation of proline and phenolic compounds. Therefore, our results showed that both enzymatic and non-enzymatic antioxidants could be influenced by the application of Mn treatments in a type-dependent manner. In general, this study revealed that Mn2O3-NPs at the tested condition could be used as biostimulants to improve germination, seedling development and further plant growth. However, they are not as effective as MnSO4 treatments. Nonetheless, these findings can be used to consider and develop Mn2O3-NPs priming in future studies to improve seed germination and seedling quality in plants.

Seed priming and exogenous application of citric acid enhance seedling growth and photosynthetic pigments and mitigate oxidative damage of soybean (Glycine max) under salt stress

Seed priming and citric acid (CA) supplementation on germination and seedling growth of soybeans were investigated. Soybean seeds were primed with distilled water (control), 1 mM CA (CA1), or 2 mM CA (CA2) and then placed for germination in Petri dishes containing distilled water or 150 mM NaCl (SS), alone or in combination with 1 mM or 2 mM CA. Germinated seeds were placed in hydroponic pots using a similar treatment regimen to that specified for the Petri dishes to obtain seedling growth and biochemical parameters. Salt stress significantly lowered germination, growth traits, relative water content (RWC), and photosynthetic pigment. When soybean seeds were primed with CA under salt stress, the germination rate, final germination percentage, seed vigor index, and number of lateral roots significantly increased. Moreover, supplementation of CA significantly increased fresh and dry shoot and root weight, plant height, RWC, and photosynthetic pigments compared to salt-treated plants. The results also displayed that salt stress considerably increased hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents compared to control plants. Spraying of CA1 and CA2 significantly lowered the levels of H2O2 and MDA in salt-treated plants. Both hierarchical clustering and PCA revealed that the effects of salt stress and CA on germination, growth characteristics, photosynthetic pigments, H2O2, and MDA concentrations strongly interacted with one another. According to the findings, CA could be applied as a seed priming and exogenous agent to help soybeans grow more quickly when exposed to salt stress.

ВЛИЯНИЕ ОБРАБОТКИ СЕМЯН РАЗНЫМИ ДОЗАМИ ГЕТЕРОАУКСИНА НА РОСТОВЫЕ ПАРАМЕТРЫ ДВУХ СОРТОВ ФАСОЛИ

Priming of seeds in auxin solution is a model of the action of auxin-producing bacteria on plant growth. The aim of the study was to identify auxin concentrations that stimulate and inhibit the growth of seedlings of two varieties of beans. Seeds were soaked for 3 hours in tenfold dilutions of heteroauxin 0,00001–100 mg/l, germinated on wet filters in the dark, growth parameters (germination energy, germination, length of axial organs of the seedling, number and length of lateral and accessory roots, root and shoot weight) were measured on the 7th day. For the Ufa variety, an increase in all growth indicators by 25-36% relative to the control occurred only at a dose of 0,001 mg/l, while the shoot/root ratio of 1.8 was as in the control. Changing this dose by an order of magnitude led to a neutral or negative effect on all growth indicators. For the Elsa variety, the growth of the length of the main root on the gradient of hormone concentrations was characterized by a two-vertex graph with a maximum value of an increase in root length by 23% to the control at a dose of 0,1 mg/l hormone. At the same time, the shoot/root ratio is 1,0. According to other indicators, no stimulating effect was found. The presence of one or more pessimums of the values of the growth indicators of seedlings on the concentration curve indicates that in both varieties the range of stimulating concentration of exogenous auxin is very narrow. Therefore, to stimulate growth, it is necessary to use precision and individual concentrations of exogenous hormone for each variety.

Effect of Multi-Walled Carbon nanotubes-based Seed Priming in Pennisetum glaucum Seedlings Affecting the Antioxidant Activities

Effect of Multi-Walled Carbon nanotubes-based Seed Priming in Pennisetum glaucum Seedlings Affecting the Antioxidant Activities

Priming Apoplast-Associated Bacillus Amyloliquefaciens LAS10 Enhances Growth and Yield Attributes of Little Millet Under Drought Stress

Little millet plant, in general, withstands various climatic changes and environmental stresses. The endophytic bacterial communities associated with these plants help the plant to develop enduring harsh conditions. Priming seeds with endophytic bacteria helps the host plant grow under adverse environments. The present study aimed to prime the seeds with apoplastic endophytic bacteria, Bacillus amyloliquefaciens LAS10 from little millet (var. ATL1) and to evaluate the efficiency to tolerate an osmotic potential of -10 bars (-1MPa). The seeds were primed with B. amyloliquefaciens LAS10 to investigate the plant growth attributes in vitro and in vivo. Induced drought stress was imposed using different concentrations of PEG6000 in vitro and by withholding the irrigation for ten days during panicle initiation in vivo. Biometric observations were recorded. The results showed significant differences both in vegetative growth parameters as well as yield attributes compared with the control under moisture stress. During the panicle initiation stage (20 DAS), the shoot length (32.26, and 28.36 cm), root length (19.1, and 17.7 cm), total plant biomass (4.61, and 2.47 g), number of productive tillers plant-1 (5, and 3), the total number of panicles plant1 (15.63, and 13.69), panicle length (9.9 cm, and 9.1 cm) and 1000 grain weight (12.91, and 11.92 g), grain yield plant-1 (16.92, and 12.24g), straw yield (21.65, and 19.31) registered more in B. amyloliquefaciens LAS10 primed plants compared to uninoculated control under both irrigated and drought stressed conditions, respectively. Thus, the present study confirmed that the inoculation of little millet with the apoplastic bacterium B. amyloliquefaciens LAS10 could promote plant growth and productivity under moisture stress. Further, the apoplastic bacterium B. amyloliquefaciens LAS10 can be recommended as a bio-inoculant for alleviating drought stress in little millet and enhancing crop fitness and sustainable little millet production.

Seed Priming of Rice Varieties with Decoyinine Improve Their Resistance against the Brown Planthopper Nilaparvata lugens

The brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae) is one of the most destructive rice pests in Asia. The microbial metabolite decoyinine (DCY) has been extracted from Streptomyces hygroscopicus. Recent studies have suggested that treating rice seeds with DCY could improve the growth and yield of rice. To further assess the effects of priming the seeds of different rice varieties with DCY on rice seedling resistance against BPH, an age-stage, two-sex life table and choice test were applied to investigate the individual fitness, population parameters, and preference behavior of BPHs in this study. The results indicated that feeding on rice seedlings grown from seeds primed with DCY significantly affected BPHs’ adult longevity, oviposition period, fecundity, as well as the net reproductive rate (R0), intrinsic rate of increase (rm), finite rate of increase (λ), doubling time (DT), and population size in terms of BPH. The honeydew excretions and the weights of BPHs fed on DCY-pretreated rice plants were remarkably lowered. The two-way ANOVA results also showed that there were significant differences in the biological parameters, honeydew excretions, and of BPH weights owing to DCY treatment, rice variety, and the interactions between DCY treatment and rice variety. Additionally, the feeding and oviposition preferences of BPHs for the pretreated rice plants were reduced. Our results imply that the priming of seeds with DCY can improve rice resistance against BPH, which could facilitate the utilization of seed priming as a new avenue for effective crop protection.

Effect of Aeration and KNO3 in Seed Priming on The Germination of Tomato (Solanum lycopersicum) Seeds

Seed priming by soaking in KNO3 has been used to enhance seed performance and crop establishment in tomatoes. However, seeds that are immersed in a solution for a long time may be deprived of oxygen during critical phases of imbibition. Aeration during priming is a solution to solve this problem. Thus, this study aims to determine the effect of aeration and KNO3 in seed priming on the germination of tomato seeds. The seeds used in this study were tomato seeds var. Palupi. This study used seven treatments i.e. non-primed, KNO3 moistened paper, KNO3 soaking, KNO3 aeration, water moistened paper, water soaking, and water aeration. The study was arranged in a completely randomized design (CRD). All data were statistically analyzed using one-way ANOVA and followed by means analysis using Fisher’s LSD (Least Significant Difference) test at P<0.05. The result showed that all priming treatments gave a better performance in FGP (Final Germination Percentage), MGT (Mean Germination Time), and GRI (Germination Rate Index) compared to the non-primed. The best treatments, however, were observed in the aeration method in either KNO3 or water in all parameters observed. KNO3 gave a slightly better performance than water in all parameters, although there was no statistical difference between the two treatments.