Overcoming seed dormancy of mooseer (Allium hirtifolium) through cold stratification, gibberellic acid, and acid scarification

2012 ◽  
Vol 23 (4) ◽  
pp. 707-710 ◽  
Author(s):  
Farshad Dashti ◽  
Hojat Ghahremani-Majd ◽  
Mahmood Esna-Ashari
2005 ◽  
Vol 15 (4) ◽  
pp. 349-356 ◽  
Author(s):  
Carol C. Baskin ◽  
Jerry M. Baskin ◽  
Alvin Yoshinaga ◽  
Ken Thompson

This study addressed the difficulty of germinating drupelets (hereafter seeds) in the multi-seeded stony dispersal units (drupes) of Leptecophylla tameiameiae (Ericaceae). Embryos in fresh seeds were 77% the length of the endosperm, and seeds inside the intact drupes imbibed water. We monitored germination at 15/6, 20/10 and 25/15°C for 162 weeks, after which each drupe was cut open and ungerminated seeds counted. Drupes contained 1–6 seeds, and the total number of seeds in all treatments and controls was 1977, with 20, 29, 25, 18, 7 and <1% of them occurring in one-, two-, three-, four-, five- and six-seeded drupes, respectively. The percentage of seeds germinating in one-, two-, three-, four-, five- and six-seeded drupes was 74, 66, 65, 72, 56 and 0, respectively. Neither warm nor cold stratification for 6 or 12 weeks significantly increased germination percentages, compared to controls incubated continuously at 25/15°C for 162 weeks, where 72% of the seeds in the drupes germinated. At 25/15°C, 24–49 weeks were required for 20% of the seeds to germinate. Warm followed by cold stratification did not promote germination, and there was no widening of the temperature range for germination. Like seeds of other species known to have deep physiological dormancy (PD), those of L. tameiameiae required extended periods of time (16 to ≥162 weeks) to come out of dormancy and germinate, gibberellic acid (GA3) did not promote germination and excised embryos failed to grow. Thus, we conclude that seeds of L. tameiameiae have deep PD. However, unlike seeds of other species with deep PD, those of L. tameiameiae required an extensive period of warm rather than of cold stratification to come out of dormancy. It is suggested that a subtype a (seeds require a long period of cold stratification to come out of dormancy) and a subtype b (seeds require a long period of exposure to warm stratification to come out of dormancy) of deep PD be recognized in the Nikolaeva formula system for classifying seed dormancy.


2012 ◽  
Vol 40 (2) ◽  
pp. 183 ◽  
Author(s):  
Elias PIPINIS ◽  
Elias MILIOS ◽  
Olga MAVROKORDOPOULOU ◽  
Christina GKANATSIOU ◽  
Maria ASLANIDOU ◽  
...  

Sexual propagation of Prunus mahaleb is difficult due to seed dormancy. To overcome dormancy and maximize germination, various pretreatments have been applied, including stratification (warm and cold), gibberellic acid (GA3), sulfuric acid scarification (AS), and endocarp removal. The results show that warm stratification (WS) prior to cold stratification (CS) does not improve seed germination and a long period of WS (3 months) is disastrous for germination. CS alone (up to 4 months) has been found to hasten and increase seed germination. Pretreatment of the seeds with exogenous GA3, during the CS period, has been observed to result in significantly higher seed germination. AS of seeds for 45 minutes prior to GA3 (1000 ppm for 24 hours) plus CS (up to 1 month) pretreatment has been considered to reduce the mechanical resistance of endocarp and improve germination. However, extended time of AS (180 minutes) prior to GA3 plus CS pretreatment has been found to harm the seeds. The removal of endocarp has been noted to significantly improve germination. Seeds without endocarp, which were pretreated with GA3 (1000 or 2000 ppm for 24 hours) and then cold stratified for 1 month, have been noted to exhibit the highest germination percentages.


2021 ◽  
Vol 19 (3) ◽  
pp. e0804-e0804
Author(s):  
Pablo Vivanco ◽  

Aim of study: Germination assays are vital in the management of material preserved in germplasm banks. The rules published by the International Seed Testing Association (ISTA) are generally those followed in such assays. In wild species, seed dormancy and inter-population variability increase the difficulty in estimating seed viability. The aim of the present work was to determine the germination requirements of the seeds from different wild populations of pasture grasses species. Area of study: Northwestern Spain Material and methods: Seeds from eight wild populations of different species of Festuca, all from northwestern Spain, were studied. Germination assays were performed under constant and alternating temperature conditions. Treatments for removing seed dormancy (cold stratification and gibberellic acid application) were also applied. A full parametric time-to event model was used for data analysis. Main results: In general, the optimum environmental temperature for germination was around 15°C for the populations of Festuca group ovina, F. gr. rubra and F. gigantea; temperatures of 20-30ºC had a negative effect. All the examined populations, except that of tall fescue (Lolium arundinaceum), showed non-deep physiological dormancy at suboptimal germination temperatures, but this was breakable by the application of gibberellic acid and by cold stratification. Research highlights: There are clear inter- and intra-specific differences in germination requirements that might be associated with place of origin. The ISTA germination assay recommendations for wild members of fescues may not be the most appropriate.


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1765
Author(s):  
Wei Zhang ◽  
Lian-Wei Qu ◽  
Jun Zhao ◽  
Li Xue ◽  
Han-Ping Dai ◽  
...  

The innate physiological dormancy of Tulipa thianschanica seeds ensures its survival and regeneration in the natural environment. However, the low percentage of germination restricts the establishment of its population and commercial breeding. To develop effective ways to break dormancy and improve germination, some important factors of seed germination of T. thianschanica were tested, including temperature, gibberellin (GA3) and/or kinetin (KT), cold stratification and sowing depth. The percentage of germination was as high as 80.7% at a constant temperature of 4 °C, followed by 55.6% at a fluctuating temperature of 4/16 °C, and almost no seeds germinated at 16 °C, 20 °C and 16/20 °C. Treatment with exogenous GA3 significantly improved the germination of seeds, but KT had a slight effect on the germination of T. thianschanica seeds. The combined treatment of GA3 and KT was more effective at enhancing seed germination than any individual treatment, and the optimal hormone concentration for the germination of T. thianschanica seeds was 100 mg/L GA3 + 10 mg/L KT. In addition, it took at least 20 days of cold stratification to break the seed dormancy of T. thianschanica. The emergence of T. thianschanica seedlings was the highest with 82.4% at a sowing depth of 1.5 cm, and it decreased significantly at a depth of >3.0 cm. This study provides information on methods to break dormancy and promote the germination of T. thianschanica seeds.


Horticulturae ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 490
Author(s):  
Saeng Geul Baek ◽  
Jin Hyun Im ◽  
Myeong Ja Kwak ◽  
Cho Hee Park ◽  
Mi Hyun Lee ◽  
...  

This study aimed to determine the type of seed dormancy and to identify a suitable method of dormancy-breaking for an efficient seed viability test of Lysimachia coreana Nakai. To confirm the effect of gibberellic acid (GA3) on seed germination at different temperatures, germination tests were conducted at 5, 15, 20, 25, 20/10, and 25/15 °C (12/12 h, light/dark), using 1% agar with 100, 250, and 500 mg·L−1 GA3. Seeds were also stratified at 5 and 25/15 °C for 6 and 9 weeks, respectively, and then germinated at the same temperature. Seeds treated with GA3 demonstrated an increased germination rate (GR) at all temperatures except 5 °C. The highest GR was 82.0% at 25/15 °C and 250 mg·L−1 GA3 (4.8 times higher than the control (14.0%)). Additionally, GR increased after cold stratification, whereas seeds did not germinate after warm stratification at all temperatures. After cold stratification, the highest GR was 56.0% at 25/15 °C, which was lower than the GR observed after GA3 treatment. We hypothesized that L. coreana seeds have a non-deep physiological dormancy and concluded that 250 mg·L−1 GA3 treatment is more effective than cold stratification (9 weeks) for L. coreana seed-dormancy-breaking.


Forests ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 319
Author(s):  
Yuhan Tang ◽  
Keliang Zhang ◽  
Yin Zhang ◽  
Jun Tao

Sorbus alnifolia (Siebold & Zucc.) K.Koch (Rosaceae) is an economically important tree in the temperate forests of Eastern China. In recent decades, ever-increasing use and modification of forestlands have resulted in major degeneration of the natural habitat of S. alnifolia. Moreover, S. alnifolia seeds germinate in a complicated way, leading to a high cost of propagation. The current study aimed to determine the requirements for breaking seed dormancy and for germination as well as to characterize the type of seed dormancy present in this species. Moreover, the roles of temperature, cold/warm stratification, and gibberellic acid (GA3) in breaking dormancy were tested combined with a study of the soil seed bank. The results showed that intact seeds of S. alnifolia were dormant, requiring 150 days of cold stratification to achieve the maximum germination percentage at 5/15 °C. Exposure of the seeds to ranges of temperatures at 15/25 °C and 20/30 °C resulted in secondary dormancy. Scarifying seed coat and partial removal of the cotyledon promoted germination. Compared with long-term cold stratification, one month of warm stratification plus cold stratification was superior in breaking dormancy. Application of GA3 did not break the dormancy during two months of incubation. Seeds of S. alnifolia formed a transient seed bank. The viability of freshly matured S. alnifolia seeds was 87.65% ± 11.67%, but this declined to 38.25% after 6-months of storage at room temperature. Seeds of S. alnifolia have a deep physiological dormancy; cold stratification will be useful in propagating this species. The long chilling requirements of S. alnifolia seeds would avoid seedling death in winter.


2020 ◽  
Vol 183 (3) ◽  
pp. 1157-1170 ◽  
Author(s):  
Haiting Wang ◽  
Yuman Zhang ◽  
Na Xiao ◽  
Ge Zhang ◽  
Fang Wang ◽  
...  

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