Pengaruh priming terhadap vigor benih kedelai (Glycine max (L.) Merril.) yang dikecambahkan pada media dengan cekaman alumunium

Kandungan aluminium yang tinggi pada tanah Ultisol merupakan salah satu masalah utama dalam budidaya tanaman kedelai mulai dari fase perkecambahan hingga pertumbuhan tanaman. Perlakuan priming pada benih diyakini mampu memperbaiki perkecambahan pada lingkungan yang kurang menguntungkan. Penelitian dilakukan untuk mengetahui pengaruh priming pada perkecambahan benih kedelai yang dikecambahkan dalam media masam dan mengandung aluminium. Penelitian disusun dalam Rancangan Acak Lengkap (RAL) pola faktorial. Faktor pertama adalah jenis priming : tanpa priming, H2O (air), KNO3 1%, KNO3 2%, GA3 50 ppm, GA3 100 ppm, dan PEG 6000 7,5%. Faktor kedua adalah varietas kedelai yaitu: Anjasmoro, Burangrang, dan Grobogan. Data dianalisis sidik ragamnya dan dilanjutkan dengan uji Beda Nyata Jujur (BNJ) 5% menggunakan program statistika R Studio. Hasil penelitian menunjukkan priming PEG 7,5% dan varietas Burangrang secara mandiri merupakan perlakuan terbaik untuk meningkatkan vigor benih kedelai berdasarkan variabel waktu muncul kecambah, kecepatan perkecambahan, dan panjang hipokotil. Implikasi penelitian ini adalah PEG 7,5% dapat digunakan untuk perbaikan perkecambahan pada tanah masam dengan kandungan aluminium yang relatif tinggi. High aluminium content in Ultisol is the main problem in soybean cultivation from germination to planting growth phases.Priming treatment is believed to improve seed germination in a poor-growing environment. This study aimed to determine the effect of priming of soybean seeds germinated under acid medium and aluminium stress. The experimental design used was Completely Randomized Design (CRD) with factorial pattern. The first factor was priming type : no priming, H2O (water), 1% KNO3, 2% KNO3, 50 ppm GA3, 100 ppm GA3, and 7.5% PEG 6000. The second factor was soybean variety : Anjasmoro, Burangrang, and Grobogan. The data obtained were analyzed using the R Studio statistic program with a 5% HSD test. The study resulted that each PEG 7.5% priming and Burangrang variety independently was the best in increasing soybean seed vigor based on sprout time emergence, germination speed and hypocotyl length. This research implicates that PEG 7.5% can be used to improve seed germination on acid soils with high aluminium content.

Evaluation of Seed Germination of Sorghum bicolor Grown After Priming with Leaf Extract and Milky Sap Exudate of Calotropis procera

A pot experiment was conducted to investigate the effect of priming with the extract of plant Calotropis procera on seed germination of Sorghum bicolor. The seeds of Sorghum bicolor were primed with different concentrations of Calotropis procera leaf extract and milky sap exudate for five days at different time intervals. In total, there were five groups of days and nine seed priming treatments. The result showed that maximum seeds were germinated on day 4 in all treatments, but it was not significantly different from day 2, 3, and day 5. Whereas the highest germination of seeds was noted in two treatments, 24 hours priming with 100% boiled leaves extract (T3) and 24 hours priming with 100% milky exudate (T4), irrespective of priming days, except one day. These results showed that both milky exudate and boiled leaf extract have a positive effect on seed germination of Sorghum bicolor; therefore, in the future, both types of extracts of Calotropis procera should be considered important for priming the seeds of different plants to improve seed germination.

Melatonin Alleviates Low-Temperature Stress via ABI5-Mediated Signals During Seed Germination in Rice (Oryza sativa L.)

With increasing areas of direct sowing, low-temperature (LT) stress drastically affects global rice production. Exogenous applications of melatonin (MT) serve as one of the effective ways to improve seed germination under various stress conditions. In this study, we found that MT treatment greatly improved the LT stress-induced loss of germination percentage and the weak performance of seedlings under LT of constant 20°C (LT20). This was largely dependent on the activated antioxidant system and enhanced activities of storage substance utilization-associated enzymes. Moreover, we also detected that exogenous feeding of MT significantly increased the biosynthesis of gibberellin (GA) and endogenous MT but simultaneously inhibited the accumulation of abscisic acid (ABA) and hydrogen peroxide (H2O2) under LT20 stress. These results suggested that MT had antagonistic effects on ABA and H2O2. In addition, MT treatment also significantly enhanced the expression of CATALYSE 2 (OsCAT2), which was directly regulated by ABA-INSENSITIVE 5 (OsABI5), a core module of ABA-stressed signals, and thus promoting the H2O2 scavenging to reach reactive oxygen species (ROS) homeostasis, which consequently increased GA biosynthesis. However, in abi5 mutants, OsCAT2 failed in response to LT20 stress irrespective of MT treatment, indicating that OsABI5 is essential for MT-mediated seed germination under LT20 stress. Collectively, we now demonstrated that MT showed a synergistic interaction with an ABI5-mediated signal to mediate seed germination, partially through the direct regulation of OsCAT2.

Bokashi leachate as a biopriming on Basella rubra L. seed germination and root development

Basella rubra L. is a type of spinach, which is edible with high nutrient composition. It is also known to be an antioxidant. However, initial germination and root growth remain an issue due to hard exterior seed coating. Thus, some may germinate within 10 to 21 days, and some may not work at all. Inhibited growth may lead to vegetative propagation and micropropagation, which fundamentally reduce the growth and yield. Basella seed treated with Bokashi leachate was found to improve seed germination and root growth. A study was conducted using food waste EM Bokashi leachate (0:1, 1:1500, 1:1000, 1:500) with biopriming duration (6 and 12 hours). The experiment was conducted in a completely random design (CRD) with 3 replications of 100 seeds, with 24 experimental units. Based on the results, a short biopriming duration (6 hours) significantly enhanced the mean germination rate, germination speed accumulated, and coefficient of germination velocity. However, germination percentage had no significant improvement by leachate. Long priming duration significantly reduced the root development due to the seed may loss of desiccation tolerance. The concentration of leachate and priming duration had no significant interaction. In order to improve the germination and root growth performance, 6 hours of seeds priming duration or 1:500 (0.2%) of food waste Bokashi leachate was recommended to soak the Basella rubra seeds.

Warm stratification improves embryos development and seed germination of Cycas revoluta

The broad objective of this research is to study the effect of warm stratification on Cycas revoluta zygotic embryos length, seed germination and plant development. Four warm treatments were applied to seeds. Our results showed that seeds storage at room temperature or 30°C improved significantly zygotic embryos length. Moreover, time of germination was significantly reduced with the warm stratification. The highest percentage of germination was obtained with seeds warm treated at 30°C for 2 months while only 25% of seeds were able to germinate in the control. Regarding seedlings development, our results demonstrated that warm stratification did not affect plant development. No significant differences have been recorded in all the evaluated parameters except for root length. Taken together, these results underlined the beneficial effect of warm stratification on Cycas revoluta seed germination and plant development and proposed a new method to improve seed germination of Cycas revoluta.

Preliminary studies on Tephrosia species: Effect of seed treatments on germination

Germination tests were conducted on the seeds of three species of Tephrosia (T. bracteolata, T. candida, and T. linearis) to investigate potential seedling establishment and possible pre-treatments to improve seed germination. Pre-culture treatments were: i) No treatment (control), ii) rubbed in sand paper, iii) soaking in boiled water for 30 seconds, iv) for 3 minutes, v) for 5 minutes, vi) soaking in concentrated sulphuric acid, and vii) soaking in water for 24 hours. After treatment, a total of two hundred and fifty seeds (5 replicates each of 50 seeds) were cultured on moist filter paper for 15 days. Cumulative percentage germination, percentage dormant seeds and germination rates were calculated. Seeds of all the species of Tephrosia exhibited innate dormancy at varying levels, but most pronounced in T. linearis. Soaking seeds in boiled water for 30 seconds to 5 minutes resulted in higher seed germination (p<0.05) than other pre-culture seed treatments in all the genotypes. Percentage hard seeds were also minimal in seeds treated this way, indicating effective dormancy alleviation in Tephrasia by these treatments. From the trial, soaking seeds in boiled water for 30 seconds is recommended as treatment of Tephrosia seeds to enhance germination and optimal potential seedling establishment.

How to improve seed germination with green nanopriming

The ability to improve the germination performance of aged or dormant seeds is significant in agriculture. Seed nanopriming is one potentially effective strategy. The method of synthesising nanoparticles (NPs) is generally chemical reduction. However, most of the reducing agents are highly toxic chemicals. Plant substitutes can replace such toxic reductants because of their environmental friendliness and hence green synthesis of NPs has arisen as an emerging technology. The technology of seed priming with green synthetic NPs is called green nanopriming. This review introduces the concept of nanopriming, which has attracted research interest in recent years due to advances in nanotechnology. The basis of green nanopriming, the method for green synthesis of NPs, conditions of green nanopriming (temperature; concentration of NPs; length of priming; nature of NPs) are elaborated. Further, the effects on seeds and the growth of seedlings are also summarised. This technology can promote germination of seeds effectively without poisoning seedlings. Therefore, green nanopriming has huge potential for enhancing crop productivity.