Germination Time Research Articles

Response of sweet pepper (Capsicum annuum) to different priming treatments on germination and early growth

Production of pepper (Capsicum annuum) is reduced by poor stand as a result of poor germination due to physiological dormancy of the seed. Therefore, a laboratory experiment was carried out to evaluate the response of sweet pepper to pre-sowing treatments, with the objective of improving seed germination and growth. The experiment used Completely Randomised Design (CRD) with four treatments replicated four times. The treatments were pre-soaking in water for 24 hours before planting; pre-chilling at 100C for 7 days before planting; pre-soaking in Potassium nitrate (KNO3) at 2.4g per 1.2 liters distilled water for 24 hours and; untreated seed (control). The parameters measured were days to 50% germination, final germination % (FG%), speed of germination, mean germination time (MGT), radicle, plumule, seedling length, and seedling vigor index. The results showed that the pre-sowing treatment of seed with KNO3 and pre-soaking in water significantly (p < 0.01) increased germination percent of sweet pepper seeds. Pre-chilling and no treatment of sweet pepper seed resulted in significant reduction of final germination percentage, radicle, plumule and seedling lengths and seedling vigor index. Results also showed an increase in number of abnormal and dead seed were pre-chilling and no treatments were used. Basing on these findings, farmers are recommended to pre-soak sweet pepper seed in KNO3 and water before sowing to enhance seed germination.

Optimizing Basil Seed Vigor Evaluations: An Automatic Approach Using Computer Vision-Based Technique

The short cultivation cycle and high essential oil content of basil plants render them a valuable raw material source for diverse industries. However, large-scale production is hindered by the lack of specific protocols to assess seed vigor; thus, a consistent supply of high-quality seeds that meet consumer demands cannot be ensured. This study investigated the effectiveness of an automated system for seedling analysis as a tool for evaluating basil seed vigor and compared it to traditional tests. For this purpose, seeds from eight commercial lots were evaluated in two separate trials spaced six months apart using the following tests: germination, first germination count, saturated salt accelerated aging, primary root emergence, mean germination time, seedling emergence, seedling emergence speed index, and computerized seedling image analysis. The parameters provided by the system allowed us to clearly and objectively classify the basil seed lots based on vigor, and the results were strongly and significantly correlated with the findings of traditional vigor tests, particularly between the vigor index and seedling length. Digital analysis of four-day-old seedlings proved to be a fast and efficient technique for evaluating basil seed vigor and has the potential for use in automating the data collection and analysis process.

Advancements in maize cultivation: synergistic effects of dry atmospheric plasma combined with plasma-activated water

Abstract In this study, we investigate the effects of pre-germinative and post-germinative plasma treatments, applied separately or in combination, to improve maize germination and early seedling development. Pre-germinative treatment consists of priming the seeds with a dry atmospheric plasma (DAP) generated by a dielectric barrier device, characterized by minimal radiative emission, low electrical power (4 W) and high emissions of O, OH and NO radicals. Post-germinative treatment, known as plasma-activated water (PAW), uses a single pin electrode device (SPED) to generate a DC discharge that features a power of 126 W and produces large amounts of OH radicals. The resulting PAW, after 5 min of SPED treatment, induces a slight acidification and increased concentrations of nitrate ions (from 24 to 250 mg l−1), nitrite ions (from less than 0.1 to 56.1 mg l−1) and hydrogen peroxide (from 0.3 to 18.5 mg l−1). Results indicate that DAP applied on maize seeds for 20 min boosts their germination rate by up to 90% (versus only 65% for untreated seeds) while reducing the median germination time by 37.5%. Then, seedling growth monitoring is achieved on control, DAP, PAW and DAP + PAW groups to assess stem length, hypocotyl length, leaf count, collar diameter and fresh/dry mass. The DAP + PAW group shows the most robust growth, demonstrating a synergistic effect of the combined treatments, particularly with significantly longer stem lengths. Additionally, physiological analyses of seedling leaves indicate a decrease in chlorophyll content despite enhanced growth, while fluorescence microscopy reveals a reduction in stomatal density in leaves treated with DAP and PAW, especially in the combined treatment group, potentially impacting photosynthetic efficiency and water regulation.

Optimizing germination in tomato (Solanum lycopersicum) seeds through non-thermal plasma treatment

Abstract This study explores the efficacy of non-thermal plasma (NTP) treatment in enhancing the germination of tomato (Solanum lycopersicum) seeds. The experimental setup utilized a dielectric barrier discharge (DBD) system with specific parameters, including voltage, frequency, and treatment duration. Optical emission spectroscopy (OES) was employed to characterize the reactive oxygen and nitrogen species (RONS) generated during plasma treatment. Seeds subjected to plasma for durations ranging from 60 to 300 s were assessed for various germination parameters, including germination percentage, mean germination time, and seedling vigor. Our findings demonstrate significant improvements in germination efficiency, particularly evident at 120 and 180 s of exposure, where germination percentages increased by 113.0% and 83.3%, respectively, compared to control (untreated) seeds. Moreover, seeds subjected to NTP showed reduced mean germination times and enhanced synchronization in germination compared to the control group. Optical characterization revealed the presence of reactive species that likely contribute to the improved seed performance. These findings highlight the promise of non-thermal plasma as an eco-friendly method for improving seed germination in agriculture.

Machine Learning Insights into Ascorbic Acid-Enhanced Germination of Black Cumin (Nigella sativa L.) under Cadmium Stress

AbstractThe objective of the present work is to study the impact of seed priming with varying concentrations of ascorbic acid (vitamin C) on the germination process of black cumin (Nigella sativa) under cadmium (Cd) stress. As expected, Cd had a great effect on germination rates and seedling growth. However, the application of ascorbic acid during seed priming effectively alleviated Cd stress and significantly increased seed vigor. Primed seeds exhibited markedly elevated final germination percentage, germination index, mean germination time, seedling length, seedling vigor index, and reduced abnormal seedling percentage. Additionally, vitamin priming reduced membrane lipid peroxidation, in treated seeds. Moreover, seed priming elicited a considerable increase in peroxidase and catalase activity, thus mitigating stress effects and augmenting seed vitality. Our experimental data allowed us to establish 100–150 mg/L as the optimal concentration range for ascorbic acid in seed priming of black cumin. These insights were further corroborated through modeling techniques based on supervised machine learning. Notably, XGBoost emerged as a proficient tool for predicting final germination percentage, mean germination time, seedling vigor index, abnormal seedling percentage, and peroxidase activity, while SVR demonstrated aptitude in forecasting catalase activity and germination index. The Gaussian method exhibited superior performance in predicting malondialdehyde content. These comprehensive findings substantiate the premise that vitamin priming with ascorbic acid serves as a promising strategy to ameliorate germination outcomes under Cd-induced stress conditions.

Evaluating the impact of Cold plasma on Seedling Growth properties, seed germination, and soybean antioxidant enzyme activity.

Cold atmospheric pressure plasma (CAP) has garnered significant attention in recent years for its potential applications in biomedical, environmental, and agricultural fields. Cold plasma treatment exhibits a variety of effects in agricultural applications, including impacts on seed germination and seedling growth; however, further research is required. Soybean serves as a fundamental source of nutrients for both animals and humans. Soybean seeds possess impermeable and thick testae, which results in prolonged germination times and suboptimal germination rates. The soybeans exhibit low uniformity. As a result, poor crop establishment and yield reduction are inevitable outcomes. Therefore, the purpose of this study was to examine the effects of Iranian soybean cultivars, such as Sari, Saba, Arian, Katoul, and Williams, on seedling growth properties, seed germination, and antioxidant enzyme activity, using argon at time intervals of 30, 60, 180, 300, and 420s. Cold plasma treatment significantly enhanced germination potential from 1.18 to 66.97%, germination index from 0.50 to 60.09%, germination rate from 1.78 to 32.17%, seedling length from 2.70cm to 78.13cm, root length from 2.87cm to 56.13cm, and seedling dry weight from 1.80g to 36.63g. Additionally, CAT activity increased from 0.88- to 4.40-fold, SOD activity from 0.86- to 5.89-fold, and APX activities from 0.40- to 4.01-fold compared to the control treatment. The findings indicated that the samples exhibited optimal results at treatment durations of 60 and 180s. The influence of plasma on the antioxidant responses of seedlings, seed germination, and growth characteristics was contingent upon the duration of treatment. Cold plasma, when applied for an appropriate duration, may enhance soybean seedling growth characteristics and seed germination.

Optimization of Sargassum bovianum Extraction Techniques for Germination of Wheat, Canola, and Corn Under Different Salinity Stress

Seaweeds are a cheap, eco-friendly, and rich source of plant growth stimulators that can mitigate the adverse effects of salinity stress. This study examined the impact of Sargassum bovianum extracts obtained through different techniques using pressure, heat, and microwave radiations on the germination and growth of wheat, corn, and canola seeds under varying salinity levels (500, 3500, and 6500 µS cm−1). The findings showed that pressure, microwave, and acidic extraction methods were the most effective in extracting polysaccharides, alginate, and nutrients from S. bovianum. Seaweed extract significantly improved the mean germination time (MGT) and germination index (GI) of wheat under high salinity stress and had a positive effect on wheat plumule length (PL) and germination percentage (GP). However, seaweed extract had no significant impact on canola seeds in salinity stress, except for improved canola PL. The PL and seedling vigor index (SVI) of corn were enhanced in low salinity levels, but most treatments reduced PL and SVI in high salinity. This study suggests that using heat, pressure, and microwave techniques for seaweed extraction results in higher polysaccharides and alginate content, leading to improved germination and plant growth, particularly in wheat and canola. These findings can help growers optimize the germination and growth of these important crops.

Designing ferulic acid-functionalized dual protein conjugates: Process-induced changes, structural interplays, and sustainable calcium fortification

This study investigates the structural changes and covalent interactions of rice glutelin and egg white proteins with ferulic acid, considering the effects of germination and whisking times. Using ternary phase diagrams, we analyzed the antioxidant properties and in vitro digestive behaviors of these protein-ferulic acid conjugates. Increased germination time enhanced the conjugate potential of rice glutelin, while prolonged whisking time increased the molecular flexibility of egg white proteins. The optimal ratio of rice glutelin to egg white proteins (6:4) resulted in higher surface hydrophobicity. In vitro digestion showed that a higher proportion of rice glutelin aids gastric digestion, while more egg white protein supports intestinal hydrolysis. Extended germination time reduced particle size and antioxidant capacities during digestion but negatively impacted calcium loading from eggshells. These findings highlight the potential of tailored protein-ferulic acid conjugates for improved functional properties and food applications.

In Vitro Propagation of Alyssum Species with Different Metal Accumulation Strategies

The Alyssum genus, with its many metal-adapted species, is a good candidate for research on phytoremediation and metal tolerance mechanisms. These goals can be supported by elaborating on an in vitro multiplication protocol. Our study aimed to determine the aseptic conditions for the growth and effective propagation of Alyssum murale, A. alyssoides, and A. montanum, each exhibiting different adaptation strategies to nickel ions. Firstly, hydrogen peroxide (H2O2) or sodium nitroprusside (SNP) were investigated in the biological Lepidium test to find their optimal concentrations that could improve the germination attributes of tested Alyssum species. The concentration of 0.5 mM H2O2 or SNP was selected for research on Alyssum seeds, which were the initial material to start in vitro cultivation. Regardless of the species, H2O2 harmed germination percentage; however, its application accelerated radicle emergence, especially in metal-sensitive genotypes, while in both metal-tolerant ones, the germination time of H2O2-treated seeds was similar to that of treated with SNP. These findings provide a novel insight into the effect of H2O2 or SNP on seeds, contributing to a better understanding of their role in the germination of different genotypes. Among tested media compositions, the synchronous plant regeneration of all species was achieved on MS medium supplemented with 0.5 mg/L 2iP and 0.1 mg/L IAA, making an essential advancement in the in vitro protocols for metallophytes.

Effects of manakin gut passage on germination of a neotropical melastome shrub (Melastomataceae)

AbstractGut passage is an important but understudied component of animal‐mediated seed dispersal that can impact germination and survival. Melastomataceae plants are abundant and ecologically important throughout the tropics, but studies have obtained contrasting results regarding effects of avian gut passage on melastome germination. We conducted a paired germination experiment to test how gut passage by four species of manakins—key avian dispersers of melastomes—affects germination of the pioneer melastome shrub Miconia rubescens. Manakin gut passage accelerated M. rubescens germination, with gut‐passed seeds germinating an average of 5.1 days earlier than controls, and percent germination of gut‐passed seeds was significantly higher at 20 and 40 days post‐planting. Interestingly, manakin species varied in their gut passage effects, with L. velutina having stronger overall germination effects than M. manacus. Within species, greater body mass was correlated with higher percent germination and shorter times to first germination. Within M. manacus, seeds passed by females had significantly shorter times to first germination than seeds passed by males. Because control seeds were manually depulped in the experiment, the observed gut passage effects are likely attributable to minor scarification of the seed coat during gut transit. Our results suggest manakin gut passage can have biologically meaningful impacts on melastome germination, and the magnitude of these effects can vary based on manakin species, mass, and sex. This study refines our understanding of the “quality” component of seed disperser effectiveness in an iconic dispersal mutualism, with implications for plant community composition and recovery of deforested neotropical ecosystems.Abstract in Spanish is available with online material.

Provenance and pretreatment effect on seed germination of twenty-six provenances of Xanthoceras sorbifolium

ABSTRACT Due to the long dormancy period and hard seed coat, the natural germination percentage of yellowhorn (Xanthoceras sorbifolium) seeds is low, which seriously hinders the large-scale cultivation of the yellowhorn. In this study, the seeds of 26 provenances with different climatic and geographical conditions were collected and the seed germination was tested, which was conducted to determine the effects of seed pretreatment methods on the germination of yellowhorn. This study showed that the germination percentage (GP), mean germination time (MGT) and germination index (GI) of 26 provenances of yellowhorn seeds in different pretreatment methods were highly significant (p < 0.01). The sand storage + clean water and sand storage + PEG almost significantly promote the GP and GI, and reduce the MGT of all provenances, while the pretreatments of warm water and cold water have almost no promoting effect on the GP and GI. In addition, this study indicates that provenances are as important as pretreatments in germination ability. Correlation between germination ability and geo-climatic data of provenances showed that low temperature can improve seed germination ability. This study showed that the seed germination ability of yellowhorn can be improved by using combined pretreatments for provenances with genetically low germination potential.

In-Vivo and In-Vitro Investigation of Germination Rate of Buried Sclerotia, and Variability in Carpogenic Germination Among Sclerotinia sclerotiorum Isolates

The sclerotia of Sclerotinia sclerotiorum serve as a primary inoculum source for initiating infections. This study aimed to evaluate the effects of environmental factors on sclerotial germination under field conditions by establishing sclerotia depots to monitor apothecia appearance over four consecutive years. Additionally, the effects of soil moisture content (25%, 50%, 75%, and 95%), air temperature (10 °C/10 °C, 14 °C/10 °C, and 18 °C/10 °C), and light conditions (white and UV light) on sclerotial germination and apothecial formation were investigated under controlled conditions with a 17 h day/7 h night regime. Furthermore, variability in carpogenic germination among S. sclerotiorum isolates was examined. From 2021 to 2024, significant differences were observed in both the sclerotia germination rate and timing of germination within the season. High soil moisture, particularly prolonged wetness, and soil temperatures between 10 and 14 °C were key factors for apothecial formation under field conditions. Under controlled conditions, higher soil moisture levels (75% and 95%) accelerated sclerotial germination, with sclerotia incubated at 14 °C/10 °C germinating earlier after 38 days than those at 10 °C/10 °C or 18 °C/10 °C. Additionally, the type of light significantly affected apothecial formation, which was observed only in treatments exposed to a combination of white and UV light. Furthermore, significant variations were also found in the duration until sclerotia of different S. sclerotiorum isolates produced the first stipe and the first apothecium, indicating that the genetic characteristics of each isolate affect carpogenic germination.

Multiplication and development in the nursery of Pterocarpus erinaceus, an endangered agroforestry species in Cote d'Ivoire

Pterocarpus erinaceus is a multi-purpose species threatened with extinction. The present study aims to contribute to the improvement of multiplication and nursery growth of Pterocarpus erinaceus hulled seeds. To this end, four pre-treatments were applied to Pterocarpus erinaceus hulled seeds to lift their dormancy in order to facilitate germination of the species. These were: untreated seeds as Control (To), soaking in ordinary water for 24 h (T1), soaking in hot water at 60°C (T2) and soaking in sulfuric acid (H2SO4) for 20 min (T3). Germination parameters such as germination rate, germination time and average germination time were evaluated. Growth in height, diameter, number of leaves and root length were determined. Germination data and growth parameters were collected. Analyses showed that soaking shelled seeds in ordinary water for 24 h was the best treatment, with a germination rate of 43%. Pre-treatment of the seeds with sulfuric acid for 20 min showed the lowest germination rate (1%), due to the sensitivity of the seeds. Furthermore, these pre-treatments had no effect on seedling growth in the nursery. Those interested in producing Pterocarpus erinaceus seedlings are advised to soak shelled seeds in ordinary water for 24 hours to ensure better germination in the nursery.

Optimization of Acacia auriculiformis A. Cunn. Ex Benth. Seed Germination Using Pretreatment Analysis

Agroforestry resources play a crucial role in conserving biodiversity, stabilizing soils and improving the livelihoods of rural populations. This study investigates the impact of different treatments on the germination of Acacia auriculiformis, an important tree species for soil restoration in Côte d'Ivoire. The work was carried out at the University Jean Lorougnon GUEDE in Daloa. The seeds used for this work were subjected to four treatments, including a control (T0); those soaked for 3 days in ordinary water (T1); a hot water treatment at 60°C (T3); a boiling water treatment at 100°C and a flame treatment (T4). A randomized block design consisting of four treatments in three blocks. The results showed that seed treatment in hot water at 100°C until cooling gave the best germination percentages and germination speed. The results also showed that soaking the seeds in water for three days produced seedlings with the shortest germination time. The study underlines the importance of pregermination for the selection of better-performing varieties and the implementation of effective reforestation programs. It also highlights the need for further research into the impacts of climate change on tree germination and growth. However, for a better policy of extension, production and improvement of this endangered forest species of socio-economic interest, mastery of the requirements of this species while maintaining optimal conditions for its germination in the nursery is more necessary.

Morphophysiological variation, vigor test, and influence of light and temperature on the germination of four cultivars of Glycine max (L.) Merrill

Soybean (Glycine max. (L.) Merrill) is a crop whose productivity depends on the quality of the seeds used. In this context, the objective of this study was to characterize the seeds physically, evaluate viability using tetrazolium, identify physiological vigor through an electrical conductivity test, and determine the influence of temperature and photoperiod on the germination of four cultivars (Ultra, Olimpo, Extrema and Foco). 200 seeds were used, measuring size, weight of a thousand seeds, moisture content, and fresh mass. In tetrazolium (1%), 100 seeds were soaked for 4 h at 25°C. For electrical conductivity, 50 seeds were submerged on 75 mL of deionized water at 25°C for periods of 4, 8, 12, 16, 20 and 24 h. In the germination process, the treatments (four replications of 50 seeds) were incubated (B.O.D.) at temperatures of 25°C, 27°C, 30°C and 35°C, under photoperiods of 12 and 14 h. The experimental design adopted was completely randomized for all experiments, and the means were subjected to analysis of variance and Tukey's test at 5% probability. The Ultra cultivar presented perimeter (38.21±3.72 mm), length of 9.98±0.24 mm, and width of 7.94±0.27 mm. The cultivars presented viability above 90%. For electrical conductivity, the 12 h period was effective for identifying vigor. The Ultra cultivar (25°C and 12 h of photoperiod) achieved 77% germination, 10 germinated seeds per day, an average germination time of 4 days and 43 germinated seeds by the third day.

Seed ecology of the arid zone invasive thistle; Centaurea melitensis L.: A study of the effects of seasonal temperature, pH, salinity and moisture stress

AbstractCentaurea melitensis L., known commonly as Malta thistle, is an aggressive and invasive weed species native to the Mediterranean region. This species now occupies a diverse range of ecosystems and climate types across the globe, including the semi‐arid zone of New South Wales, Australia. This semi‐arid climate differs dramatically from its native Mediterranean climate, therefore, we aimed to identify if local adaptations in the seed ecology for C. melitensis have developed. Seeds were collected from mature C. melitensis at Nanya Station, located within the Scotia region of NSW, and then transported to Federation University Australia, Mt. Helen, Victoria. Under laboratory conditions, mature seeds were tested for their germination responses to temperature (17/7, 25/15, 30/20, 35/25°C), photoperiod (12 h light and 12 h dark [L/D], 24 h dark [D]), salinity (0, 25, 50, 100, 150, 200, and 250 mM), osmotic potential (0, −0.1, −0.2, −0.4, −0.6, and −0.8 MPa), and pH (5, 6, 6.2, 7, 8, 9, and 10). The seeds achieved 100% germination in the 17/7°C treatment, with light not being a limiting factor. The seeds exposed to the 25/15°C (D) and 30/20°C (D) treatments also maintained high germination percentage, whilst germination was significantly reduced in the 35/25°C (D) treatment. The L/D photoperiod maintained a 77.5% germination rate at 35/25°C. Whilst increased salinity reduced seed germination from 97.5% in the control to 6% at 250 mM, this species nevertheless demonstrated resistance to osmotic stress with 23% germination observed at 0.8 MPa. Germination exceeded 90% at all of the soil pH treatments, although mean germination time was significantly reduced when seeds were treated with a solution of pH 10. Our results demonstrate that the C. melitensis seeds collected in Australia's semi‐arid zone demonstrated high germination plasticity and are capable of competitive germination in warmer and drier conditions compared to its native Mediterranean climate. Therefore, management efforts that prioritise restricting the spread of C. melitensis seeds into new environments, for example through practising correct sanitation protocols, coupled with the early detection and control of emerging populations will be critical for C. melitensis management in Australia.

Seed priming enhances seed germination and plant growth in four neglected cultivars of Capsicum annuum L.

Priming is basically a water-based technique inducing controlled seed rehydration to trigger the metabolic processes normally activated during the early phase of germination. It is regarded as an ecofriendly approach alternative to fertilizers in traditional agriculture, but also a method to synchronize off-field crops and resume stored seeds, improving vigor, and allowing for a rapid, uniform seedling emergence. In this work we tested several methods of seed priming (i.e., hydro-priming, halopriming by KNO3, and acid priming with HCl) in four ancient and neglected cultivars of Capsicum annuum L., a crop species belonging to Solanaceae family cultivated worldwide. We followed germination performance, seedling growth and selected morphological traits, antioxidant production in the leaves, and protein content of the seeds. Apart from acid priming, which inhibited root emergence, both hydropriming and halopriming decreased the mean germination time in all cultivars. The best treatments were KNO3 6% for 96 h > KNO3 4% for 48 h > hydropriming for 24 h. In particular, KNO3 6% for 96 h in all four cultivars significantly increased plant growth, simple vigor index, development germination index, leaf antioxidant concentration and protein content in the seeds, in comparison to control and other priming treatments, indicating the prompt activation of pre-germinative processes.

Germination process impact on proximate, minerals, and phytochemicals of malt barley, Abyssinian purple-colored barley and wheat

In this study we aimed to determine germination time impact on the proximate, minerals and phytochemicals content of malt barley, Abyssinian purple-colored barley and wheat grow in Southern highland of Tigray. Germination evenly affected protein, carbohydrate, iron, calcium, zinc, and phenolic. It also inversely affected the fiber, fat, ash, tannin, and anthocyanin content of the colored cereals. The crude protein content of raw cereals, which ranged from 6.30 to 8.40% increased after germination to 6.60–8.90%. Mineral element of mature cereals varied across cultivars and their level increased (171.4–223.3 to 227.3–249.8 mg/100 g) after germination. After 72 h germination time, condensed tannin concentration decreased from 2.27 to 5.24 into 0.20–3.6 mg GAE per 100 g. The phenolic content tripled from 63.5 to 189.6 mg GAE per 100 g in germinated samples. Anthocyanin of raw whole purple colored-barley had highest value (303.0 mg GAE/100 g) and followed by raw purple colored wheat (266.0 mg GAE/ 100 g). Both purple colored-barley and -wheat showed decreased TAC after germination, along with changes in protein, mineral and tannin. When after germination, it drastically decreased into 207.2 and 137.4 mg GAE/100 g. Germinated cereal which had higher protein and mineral content showed very strong positive correlation. A germination process should be accounted for improved utilization of these purple-colored cereals might be best alternative sources of malt. While germination inversely influenced to anthocyanins. Thus, it is vulnerable molecules that require special stabilization treatments during food preparation and processing.

Biochemical Changes and Germination Response of Indian Sandalwood (Santalum album L.) Seeds Subjected to Biopriming Techniques and Variable Post-priming Storage

Understanding of the storage behaviour of endangered plant species such as Indian Sandalwood, Santalum album L. is important for successful conservation. We tested biopriming method with five biopriming agents (e.g. Effective microorganisms; Plant growth promoting rhizobacteria (PGPR-I and PGPR-II); Pseudomonas fluorescens and Piriformospora indica) with four uniform durations of treatments viz. 2, 4, 6 and 8 days. Hydropriming was also performed with similar condition for comparison of seed performance. The study examined the biochemical changes that occur in Sandalwood seeds during different post-priming storage periods (0, 30, 60, 90 days) to assess the efficacy of biopriming techniques on seed germination and health. Biopriming with Pseudomonas fluorescens for eight days recorded the highest germination percentage (70.67%) and the highest germination rate index (0.84). Longer durations of PGPR-I and Piriformospora indica treatment (6-8 days) lowered the imbibition period and mean germination time while increasing the germination rate. After a post-priming storage period of 30 days, only EM and Pseudomonas fluorescens treated seeds germinated while all other treatments failed to germinate. Absence of germination in any biopriming group at 60 and 90 days storage period indicated that the sandal seeds deteriorated over extended storage period. The reduction in seed viability of sandal seeds was consequent to the changes in the biochemical characteristics and action of enzymes (α and β amylases) involved in seed food reserve depletion and loss in membrane integrity.

Response of GA3, NAA, and KNO3 treatments on in vitro seedgermination and shoot performance of highland bamboo(Oldeania alpina L.)

Oldeania alpina (K. Schum) Stapleton is an African alpine bamboo, native of Ethiopia to Zambia. The untreated seeds of O. alpina do not give good germination. Therefore, the effects of different seed pretreatments on germination and shoot quality were evaluated. The pre-sowing treatments were highly significant (P ≤ 0.001) for all studied parameters. The seeds subjected to 8% Gibberellic acid (GA3) treatment produced the highest germination percent (30%) while 6% NAA naphthalene acetic acid produced 23% germination. The values of MGT (mean germination time), PV (peak value) and VI (vigorous index) were also analyzed and interpreted to evaluate the germination of seed and shoot quality of the emerging plants. Moreover, the highest values for morphological parameters were recorded for 8% GA3 and 6 % NAA. Hence, the use of 8% GA3 or 6% NAA pretreatment is recommended to enhance the germination and shoot quality of O. alpina.