Seed and seedling morphology of Bauhinia scandens L.

Bauhinia scandens has potential importance as an ornamental and medicinal plant. Researchers have isolated and identified 1-O-alkylglycerol in the leaves of the B. scandens plant, and established antitumor properties using the Brine Shrimp toxicity test, an internationally accepted bioassay. Although this species has high potential, little is known about the viability of seedling production and the morphology of these plants, particularly in terms of seed characteristics and initial stages of germination. The objective of this study was to characterize the seed morphology, germination, and seedlings of B. scandens. Seed water content, weight, and coloration were evaluated. This study also included a description of seed biometrics, external and internal structures, germination, and seedling morphology. Internal seed morphology was evaluated by the anatomical sectioning and X-ray methods. The morphology data obtained were subjected to descriptive statistical analysis and germination data were determined using Cramér’s V. B. scandens seeds have a coloration ranging from very dark grayish-red to dark reddish-brown, flat oblong shapes, and rounded bases and apexes with full or slightly undulating margins. Healthy seedlings are produced mainly by seeds with well-formed internal structures. The reddish petiole of the seedling leaves is a taxonomic character for B. scandens identification. The non-domestication and genetic variability of this species reflect on the seed and seedling color and size variation.

Post-dispersion humidity condition alters the surface of the testa and the proportion of seeds with physical dormancy in Erythrina speciosa

Seeds of Papilionoideae (Leguminosae) species lose water after dispersal, increasing the proportion of water-impermeable seeds (physical dormancy, PY). However, changes in testa structure during this process remain unknown. The present study investigated how variation in relative humidity (RH) during the post-dispersion period affects the proportion of seeds of Erythrina speciosa with PY. Seeds from two populations were stored in drier (40% RH) and wetter (80% RH) environments and periodically subjected to physiological analysis (seed water content, imbibition and germination) and structural analysis of the testa (light and scanning electron microscopy). Drier storage resulted in seed dehydration, increasing the proportion of water-impermeable seeds and closure of cracks in the mucilaginous stratum. In contrast, wetter storage led to an increase in seed water content, a decrease in the proportion of seeds with PY, and the formation of cracks. As a result of variation in environmental humidity, we conclude that changes occur in the mucilaginous stratum of seeds, altering water loss and, consequently, the proportion of seeds with PY. Environments with low humidity cause a decrease in seed water content, the closing of cracks in the mucilaginous stratum, and, consequently, an increase in the proportion of water-impermeable seeds. On the other hand, a high RH environment increases the seed water content and the formation of superficial cracks, through which water enters during imbibition, causing a decrease in the proportion of seeds with PY.

Harvest times and seed germination of three safflower genotypes

ABSTRACT: The safflower (Carthamus tinctoriusL.) has an uneven flowering and fruiting, which can cause problems in seed production and harvesting in regions with hot and humid climates. However, little is known about the optimal safflower harvest time. Therefore, this study evaluated the optimumtiming for seed harvest of three safflower genotypes (2106, S-325, and 7329).The experiment was a randomized complete block design with six replications. The harvest started 16 days after flowering (DAF) and ended at 52 DAF. Ten harvests were made in total. Seed water content, seeds fresh and dry matter, seed germination, and first germination counts were evaluated.Genotypes 2106 and 7329 had germination rates of 79% and 91%, respectively, at 34 and 38 DAF, while genotype S-325 had 90% germination at 37 DAF. Harvesting at 52 DAF combined with a rainy season impaired the germination of safflower seeds. The harvest time most suitable for safflower occurred between 34 and 42DAF, when the seeds have the seed water content between 26% and 33%.

The role of seed water content for the perception of temperature signals that drive dormancy changes in Polygonum aviculare buried seeds

Seedling emergence in the field is strongly related to the dynamics of dormancy release and induction of the seed bank, which is mainly regulated by soil temperature. However, there is limited information on how temperature-driven effects on dormancy changes are modulated by the seed hydration-level. We investigated the effect of seed water content (SWC) on the dormancy release and dormancy induction in Polygonum aviculare L. seeds. We characterised quantitatively the interaction between seed water content (SWC) and temperature through the measurement of changes in the lower limit temperature for seed germination (Tl) during dormancy changes for seeds with different SWC. These relationships were inserted in existing population-based threshold models and were run against field obtained data. The model considering SWC was able to predict P. aviculare field emergence patterns. However, failure to consider SWC led to overestimations in the emergence size and timing. Our results show that in humid temperate habitats, the occurrence of eventual water shortages during late-winter or spring (i.e. short periods of water content below 31% SWC) can affect soil temperature effects on seed dormancy, and might lead reductions in the emergence size rather than to significant temporal displacements in the emergence window. In conclusion, SWC plays an important role for the perception of temperature signals that drive dormancy changes in buried seeds.

Design of Measurement of Coffee Seed Water Content Using Load Cell Sensor On Coffee Dryer

The conventional method of drying coffee beans that depend on sunlight (drying) has a number of drawbacks, one of which is that the drying productivity takes a long time. In general, coffee drying is carried out until it reaches a moisture content of 12.5% to achieve a quality bean standard. Mathematically, the moisture content can be assessed by paying attention to the initial weight of the coffee beans and the final weight of the coffee beans. So that the use of the Load Cell sensor to read the depreciation value of the coffee bean weight on a coffee dryer powered by Hybrid Collector and LPG coffee beans. Research that has been carried out during 200 minutes of drying in a coffee dryer, the Load Cell sensor is able to read the depreciation value of the coffee bean weight by 114 grams from the initial weight of 978 grams. Therefore, it can be concluded that the final moisture content of coffee beans has reached 12.01% and the final weight of coffee beans is 864 grams.

PEMATAHAN DORMANSI BENIH AREN (Arenga pinnata (wurmb.) Merr.) PADA TINGKAT KEMASAKAN YANG BERBEDA MENGGUNAKAN METODE PERENDAMAN

This study aims to find out the effect of submersion by using 1% acetic acid, 100% palm juice, and 100% coconut water to break the dormancy of palm seeds at different maturity levels. The research was conducted in the Green House of Forestry Study Program, University of Mataram, using the experimental method with Complet Random Design (CRD) three factors. The first factor is the maturity level consists of 3 levels, the second factor is the submersion liquid substance consist of 3 levels, and the third factor is the period of submersion consist of 4 levels.The results of this study indicate that maturity rate gives significant influence on the following parameter i.e: percentage potency of seed germination, rotten seed, seed weight, seed moisture content, and embryo lenght, while seed dormancy parameter is not significant. The submersion factor significantly influenced on the following parameter i.e: seed weight, and seed water content, while the other parameters are not significant. The submersion period factor is significant only on seed moisture content and the embryo lenght, while the other parameters have no significant effect. While in all interactions between factors show no significant result on all parameters.

Extended low temperature and cryostorage longevity of Salix seeds with desiccation control

Salix xerophila, S. maximowiczii, and S. koreensis are species of willow native to Korea that are important for bioenergy production. However, the native range of these species has narrowed in recent years due to the impact of climate change. Seeds of these Salix species lose viability within 4 weeks at ambient temperature, and within 4 months at -4°C. Preservation techniques are urgently needed to protect these valuable resources. The effects of seed water content (SWC; 3%, 6%, 9%, 12%, 18%, and 24%) and temperature (ambient, 4°C, -18°C, -80°C, and -196°C) on storage stability were investigated for up to 48, 52, or 60 months, depending on species. Optimal storage temperature and SWC varied between species. S. xerophila seed could be stored without deterioration for 60 months with 9% SWC at -80°C, but rapidly lost viability when stored at -18°C. In S. maximowiczii and S. koreensis, 100% and 90% of normal germination, respectively, was maintained with 18% SWC at -18°C or -80°C. Thus, for some Salix species, storage at -18 and -80°C may provide an economical alternative to cryopreservation or medium-term storage for the maintenance of seedbanks or breeding stocks.

Effect of Different Seed Water Content and Storage Duration towards Seed Viability of Local Genotype Brown Rice Daro Merah

Most of rice seeds experience after ripening problem which then result in seed dormancy. This kind of dormancy could be broken through various types of treatments, including storaging in dry place for certain period. This study was aimed to evaluate the combination between seed water content and storage duration to induce the seed germination of local genotype brown rice, Daro Merah. Various levels of seed water content (6-10, 11-15, 16-20 and 21-25 %) and storage duration (2, 4, 6 and 8 weeks) were evaluated to identify its effect on Daro Merah seed germination. Data were analyzed using two-way analysis of variance where significance were further proceeded using Duncan’s New Multiple Range Test with a p>0.05. The results showed that seed germination of Daro Merah reached 95 % at five days after seeding when the seed water content was maintained at 6-10% and stored for 8 weeks. After 14 days, the germination reached 99 % and most of the seeds showed some shoots emerged from the soil. Keywords: Brown rice, germination, seed water content, storage duration, Daro Merah