The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in whic...The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in which there were enough germinating individuals), and the effect of storage of seed and fruit on germination of seed was studied in 41 species (in which there were enough seeds and germinating individuals). Most of the species began to germinate within 60 d. Hypogeal species had longer dormancy than epigeal species. Dormancy of fleshy seeds and seeds in pulpy fruit was also longer than that of dry seeds. There were no significant differences in length of dormancy (LD, days from sowing to germination) between fleshy seeds ripening in summer and those ripening in winter and spring, and between big seeds and small seeds. Seeds in pulpy fruit or fleshy seeds had more germination than the dry seeds ( P <0.05), however, percentage germination was not significantly correlated with water content of fresh seeds. Water loss in the seeds could obviously affect percentage germination, especially during the early three days when the seeds were laid open in air in the laboratory. When water content of the seeds decreased to about 20% (fresh weight basis), percentage germination became very low, this happened when the seeds were laid open in air for 10-14 d. Percentage germination decreased with the length of storing in refrigerator ((4±1) ℃), but it was not markedly affected for one month's storage, with a decrease by 8.3% in comparison with the fresh seeds, and it was greatly affected by storing for more than three months, with values decreasing by 37%, 63%, and 81% for three months', six months' and 12 months' storage respectively. Difference in percentage germination as well as in LD was not significant for most lots after different storing periods between big seeds and small seeds, between fruit storage and seed storage, and between seeds in pulpy fruits or fleshy seeds and dry seeds.展开更多
The eggplant (Solanummelongena L.) is widely cultivated across the world.Technology regarding the in vitro germination and preservation of eggplant pollen is important for the production of hybrid seeds.In this work,t...The eggplant (Solanummelongena L.) is widely cultivated across the world.Technology regarding the in vitro germination and preservation of eggplant pollen is important for the production of hybrid seeds.In this work,the suitable cultural medium and time for the germination of fresh and dried pollen was investigated.The results showed that a suitable medium for eggplant pollen germination was 0.5% agar+5% sucrose+0.01% boric acid+0.01% GA3,the suitable culture time was 2 h for fresh pollen and 4 h for dried pollen stored at low temperature.GA3 could induce the germination of dried and stored pollen. The better way to dry anthers was 4 h in a desiccator at 25~30℃.We also found that pollen from the second to the fourth branch has the highest germination rate. Furthermore,there were no significant differences in the seed setting rates among the different storage temperatures and storage times,whereas the number of viable seeds formed per fruit differed significantly,which was 87.3% more for pollen stored at -80℃ and fresh pollen than that stored at 4℃.This work optimized pollen storage conditions and is helpful to eggplant hybrid seed production.展开更多
A field trial was set in 2018/2019 season to investigate </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">capacity of cashew seeds to ...A field trial was set in 2018/2019 season to investigate </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">capacity of cashew seeds to germinate and its vegetative performance with respect to </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">storage </span><span style="font-family:Verdana;">period at Agricultural Research Institute-(TARI-Naliendele), Mtwara-Tanzania.</span><span style="font-family:Verdana;"> The variable investigated was </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">duration of </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">cashew seeds storage period. Cashew seeds were harvested at polyclonal seed gardens (PSG) for three har</span><span style="font-family:Verdana;">vesting seasons 2016, 2017 and 2018 consecutively;seeds were sorted, weighe</span><span style="font-family:Verdana;">d and soaked before sowing to test viability in respective to storage time. Using </span></span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">randomized complete block design obeying factorial approach the experiment was laid with three replications. The observed growth parameters were height (cm), number of leaves, leaf length (cm), leaf width (cm), leaf area (sq cm), leaf area index (LAI), canopy diameter (cm) and seedlings canopy ground area (sq cm). </span><span style="font-family:Verdana;">The a</span><span style="font-family:""><span style="font-family:Verdana;">nalysis was done by using GenStat under Duncan Multiple Range Test (DMRT) on seed germination. </span><span style="font-family:Verdana;">The findings indicated that cashew seeds harvested in 2018 were the superior in both germination and growth vigor differing significantly (p</span></span><span style="font-family:""> </span><span style="font-family:Verdana;"><</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.05) from other seeds harvested in the previous years. Cashew seeds harvested in 2017 were weak and those harvested in 2016 were the worse such that no seeds were able even to germinate. Thus, it is recommendable to sow cashew seeds harvested at</span><span style="font-family:Verdana;"> the</span><span style="font-family:Verdana;"> current season for sowing than those stored for more than a year.展开更多
In order to explore the best storage temperature and storage period of dragon fruit seeds,with the constant-humidity germplasm cold storage of Guangxi Academy of Agricultural Sciences as a platform and storage tempera...In order to explore the best storage temperature and storage period of dragon fruit seeds,with the constant-humidity germplasm cold storage of Guangxi Academy of Agricultural Sciences as a platform and storage temperature as an environmental factor,the germination characteristics of dragon fruit seeds and seedling growth characteristics under low temperature storage(8,4,-1,-10℃)and room temperature storage(25-30℃)over time were explored.The results showed that with the extension of the storage time,the seed germination rates,germination index,healthy seedling rates,seedling heights and fresh weights of 10 seedlings of the three dragon fruit varieties showed basically the same trends,showing a downward trend.After 367 d of cold storage,the germination rate decreased from 100%to 92.33%-98.00%,and the room temperature treatments decreased to 54.00%-86.30%;and the healthy seedling rates of cold-stored seeds decreased from 96.33%-98.00%to 77.33%-97.3%,and the values of the room temperature treatments dropped to 12.00%-68.33%.The germination rates,germination index,healthy seedling rates and seedling heights of the three dragon fruit varieties stored at low temperatures were basically significantly higher than those of the room temperature treatments within 367 d of storage.The germination rates of the three varieties stored at 8℃had no significant differences from other low temperature treatments,but the germination index was significantly lower than other low temperature treatments at 367 d.It showed that low temperature storage at-10-8℃could significantly prolong the vigor and storage time of dragon fruit seeds.Considering cost and other factors,it is better to store dragon fruit seeds in a dry environment at 4℃.The seeds stored at 4℃for 1 year showed a germination rate maintained over 90%and a healthy seedling rate over 85%.展开更多
Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). T...Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). The germination of95 accessions, accounting for 0.51% of the total, declined significantly from above 80% to below 70%. For each crop ofcarrot (Daucus carota var. sativa DC.), lettuce (Lactuca sativa L.), cotton (Gossypium sp. L.), flax (Linum usitatissimumL.) and castor-oil plant (Ricinus communis L.), the mean monitored germination percentage declined significantly as awhole, of which carrot and lettuce seeds lost viability more rapidly. Seed initial germination percentage and pre-storageenvironments affect subsequent seed viability in storage.展开更多
Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even t...Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3).展开更多
Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the e...Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses: modern cold room (5℃), mud house (15℃), concrete block house (17℃ or corrugated iron house (20℃) for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation (p 0.01) in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room (41%) and the mud house (38%) maintained the same level of germination as the intitial germination of the seedlotds (42%). The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots (r 0.80; p 0.01). Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deepphysiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room (5℃) up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level.展开更多
Two psammophile-dominated Artemisia semi-shrubs (A. wudanica and A. halodendron) and two annual Artemisia forbs (A. sieversiana and A. scoparia) bear significant ecological functions in Horqin Sandy Land, but syst...Two psammophile-dominated Artemisia semi-shrubs (A. wudanica and A. halodendron) and two annual Artemisia forbs (A. sieversiana and A. scoparia) bear significant ecological functions in Horqin Sandy Land, but systematical information on their achenes' germination is very limited. A set of studies were conducted to evaluate seed germination responses to storage periods and methods, different temperatures, lights conditions and sand burial depths, in order to determine inter-specific germination variation in the same genus and to explain how the species adapt to its microhabitat. Fresh achenes of A. wudanica, A. halodendron and A. sieversiana showed high germination capacities, but those of A. scoparia had obvious innate dormancy, which could be broken by chilling and dry storage, especially long-term dry storage. Achene germination of the two semi-shrubs preferred lower temperature fluctuation (10 to 22℃) and was not sensitive to light. But the two annuals preferred higher temperature fluctuation (34 to 22℃) and strong light for their achene germination. These four Artemisia species showed similar responses to sand burial, i.e. soil surface was most favorable for seedling emergence, and the deeper the sand burial, the fewer the seedling emergence. For the two semi-shrubs, their microhabitats are sand dunes with high temperature and intense light, which are not favorable for germination and seedling survival. Only rainfall contributes to temporary decrease of temperature and then triggers germination. We deduced that germination is not the main but a supplementary repro- ductive mode for the two semi-shrubs in sand dunes. For the two annuals, achene germination is the only reproductive mode, but different responses have been developed for microhabitat adaptation. For A. sieversiana, high germination capacities in wide temperature ranges and all light conditions could improve its competition and advancement in the wettest microhabitats. For A. scoparia, obvious innate dormancy of fresh achenes and germination inhabitation under unfavorable conditions are important adaptation to environmental disturbances.展开更多
We performed desiccation and storage trials to better understand storage behavior of Knema attenuata seeds. Mature seeds with moisture content (MC) of 31% exhibited 73% germination. During the period of desiccation ...We performed desiccation and storage trials to better understand storage behavior of Knema attenuata seeds. Mature seeds with moisture content (MC) of 31% exhibited 73% germination. During the period of desiccation (open lab condition) seeds with MC 23% showed 40% germination. After further drying to MC 21% germination was reduced to 16%. Complete loss in viability resulted when seed moisture was reduced to 18%. The seeds stored at -10℃, 0℃, 10℃ and 28±2℃ (open lab condition) lost their viability within 10 days. Seeds stored in sealed polythene hags and moist sand retained viability for more days than did seeds stored under all other storage conditions. Sensitivity of seeds to lower temperature and desiccation suggest that the storage behavior of K. attenuata seeds is recalcitrant. Seeds stored in moist conditions can, at best, be stored for a period of two months.展开更多
In order to enhance the seed storability and supply high-quality seeds for vegetation restoration in the arid and semi-arid regions in Northwest China,the effects of ultra-drying and accelerated aging on the physiolog...In order to enhance the seed storability and supply high-quality seeds for vegetation restoration in the arid and semi-arid regions in Northwest China,the effects of ultra-drying and accelerated aging on the physiological characterstics of Melilotus suaveolens seeds were studied.Melilotus suaveolens seeds were dried in a desiccator containing silica gel to 80,53,42,33,23 and 16 g·kg-1 of moisture contents(MC),respectively.The parameters of the seed quality including germination energy(GE),germination percentage(GP),relative conductivity(RC),dehydrogenase activity(DA) and α-amylase activity(AA) were determined after ultra-drying and accelerated aging.The results showed that ultra-dried seeds with 42 g·kg-1 of MC showed the minimum changes of GE and GP before and after seed aging.Moreover,ultra-dry seeds with 42 g·kg-1 of MC showed higher DA and AA,and lower RC than non-ultra-drying seeds.Therefore,ultra-drying to 42 g·kg-1 of MC was helpful for M.suaveolens seed storage.展开更多
Seed storage reserves and organelles after scarification(chemical,mechanical,control)of bambara groundnut with different seed coat colours(cream,light brown and brown)were examined in relation to germination vigour.Se...Seed storage reserves and organelles after scarification(chemical,mechanical,control)of bambara groundnut with different seed coat colours(cream,light brown and brown)were examined in relation to germination vigour.Seed storage proteins,oil and sugar content,starch granules and protein bodies,germination vigour index(GVI)and mean germination time(MGT)were measured.There were significant(p<0.05)effects of seed scarification on protein body diameter,seed oil content and sugar content.Chemical scarification resulted in seeds having larger starch granules,followed by the control and mechanical scarification that resulted in seeds having smaller starch granules.Mechanical scarification had the highest(p>0.05)protein density,followed by chemical scarification and control seeds that had the lowest protein density.Seeds from the control had the highest oil content,followed by seeds from mechanical scarification and seeds from chemical scarification that had the lowest oil content.Seeds from the control and chemical scarification had larger diameter of protein bodies and sugar content.Seed coat colour significantly(p<0.05)influenced the area and diameter of protein bodies,starch granule area,seed sugar content.Brown seeds produced larger protein bodies and the highest oil content,while light brown seeds had larger area of starch granules and the highest sugar content.Seed storage reserves had an influence on bambara groundnut germination vigour.While favouring dark coloured seeds such as light brown and brown,bambara groundnut seed users should adapt chemical seed scarification to enhance germination vigour of this crop.展开更多
We examined the influence of storage time on germinability and tube growth of freeze stored pollens collected from 25 wild male plants in Actinidia eriantha variety. Pollens were stored in freezer at - 20°C ...We examined the influence of storage time on germinability and tube growth of freeze stored pollens collected from 25 wild male plants in Actinidia eriantha variety. Pollens were stored in freezer at - 20°C for six months and one year periods to determine changing at germinability in time. In vitro germination was conducted in certain cultural medium defined for Actinidia genus. The results showed that the germination percentages and tube lengths of genotypes decreased at the end of storage period. MH22, MH45, MH47, MH56, MH67, MH70, MH71, MH72, MH74, MH55 and MH61 genotypes were evaluated as vigor genotypes, because they maintained their viability and germination capability displaying statistically insignificant decreasing although their tube lengths significantly decreased except MH67. This investigation provided to determine some robust wild male germplasm resources in A. eriantha in point of durability of pollens against long term conservation for using at future pollination and breeding programs.展开更多
文摘The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in which there were enough germinating individuals), and the effect of storage of seed and fruit on germination of seed was studied in 41 species (in which there were enough seeds and germinating individuals). Most of the species began to germinate within 60 d. Hypogeal species had longer dormancy than epigeal species. Dormancy of fleshy seeds and seeds in pulpy fruit was also longer than that of dry seeds. There were no significant differences in length of dormancy (LD, days from sowing to germination) between fleshy seeds ripening in summer and those ripening in winter and spring, and between big seeds and small seeds. Seeds in pulpy fruit or fleshy seeds had more germination than the dry seeds ( P <0.05), however, percentage germination was not significantly correlated with water content of fresh seeds. Water loss in the seeds could obviously affect percentage germination, especially during the early three days when the seeds were laid open in air in the laboratory. When water content of the seeds decreased to about 20% (fresh weight basis), percentage germination became very low, this happened when the seeds were laid open in air for 10-14 d. Percentage germination decreased with the length of storing in refrigerator ((4±1) ℃), but it was not markedly affected for one month's storage, with a decrease by 8.3% in comparison with the fresh seeds, and it was greatly affected by storing for more than three months, with values decreasing by 37%, 63%, and 81% for three months', six months' and 12 months' storage respectively. Difference in percentage germination as well as in LD was not significant for most lots after different storing periods between big seeds and small seeds, between fruit storage and seed storage, and between seeds in pulpy fruits or fleshy seeds and dry seeds.
文摘The eggplant (Solanummelongena L.) is widely cultivated across the world.Technology regarding the in vitro germination and preservation of eggplant pollen is important for the production of hybrid seeds.In this work,the suitable cultural medium and time for the germination of fresh and dried pollen was investigated.The results showed that a suitable medium for eggplant pollen germination was 0.5% agar+5% sucrose+0.01% boric acid+0.01% GA3,the suitable culture time was 2 h for fresh pollen and 4 h for dried pollen stored at low temperature.GA3 could induce the germination of dried and stored pollen. The better way to dry anthers was 4 h in a desiccator at 25~30℃.We also found that pollen from the second to the fourth branch has the highest germination rate. Furthermore,there were no significant differences in the seed setting rates among the different storage temperatures and storage times,whereas the number of viable seeds formed per fruit differed significantly,which was 87.3% more for pollen stored at -80℃ and fresh pollen than that stored at 4℃.This work optimized pollen storage conditions and is helpful to eggplant hybrid seed production.
文摘A field trial was set in 2018/2019 season to investigate </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">capacity of cashew seeds to germinate and its vegetative performance with respect to </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">storage </span><span style="font-family:Verdana;">period at Agricultural Research Institute-(TARI-Naliendele), Mtwara-Tanzania.</span><span style="font-family:Verdana;"> The variable investigated was </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">duration of </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">cashew seeds storage period. Cashew seeds were harvested at polyclonal seed gardens (PSG) for three har</span><span style="font-family:Verdana;">vesting seasons 2016, 2017 and 2018 consecutively;seeds were sorted, weighe</span><span style="font-family:Verdana;">d and soaked before sowing to test viability in respective to storage time. Using </span></span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">randomized complete block design obeying factorial approach the experiment was laid with three replications. The observed growth parameters were height (cm), number of leaves, leaf length (cm), leaf width (cm), leaf area (sq cm), leaf area index (LAI), canopy diameter (cm) and seedlings canopy ground area (sq cm). </span><span style="font-family:Verdana;">The a</span><span style="font-family:""><span style="font-family:Verdana;">nalysis was done by using GenStat under Duncan Multiple Range Test (DMRT) on seed germination. </span><span style="font-family:Verdana;">The findings indicated that cashew seeds harvested in 2018 were the superior in both germination and growth vigor differing significantly (p</span></span><span style="font-family:""> </span><span style="font-family:Verdana;"><</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.05) from other seeds harvested in the previous years. Cashew seeds harvested in 2017 were weak and those harvested in 2016 were the worse such that no seeds were able even to germinate. Thus, it is recommendable to sow cashew seeds harvested at</span><span style="font-family:Verdana;"> the</span><span style="font-family:Verdana;"> current season for sowing than those stored for more than a year.
基金Basic Operating Expenses of Guangxi Academy of Agricultural Sciences(GNK 2015YT98,GNK 2020YM21,GNK 2020YM20)。
文摘In order to explore the best storage temperature and storage period of dragon fruit seeds,with the constant-humidity germplasm cold storage of Guangxi Academy of Agricultural Sciences as a platform and storage temperature as an environmental factor,the germination characteristics of dragon fruit seeds and seedling growth characteristics under low temperature storage(8,4,-1,-10℃)and room temperature storage(25-30℃)over time were explored.The results showed that with the extension of the storage time,the seed germination rates,germination index,healthy seedling rates,seedling heights and fresh weights of 10 seedlings of the three dragon fruit varieties showed basically the same trends,showing a downward trend.After 367 d of cold storage,the germination rate decreased from 100%to 92.33%-98.00%,and the room temperature treatments decreased to 54.00%-86.30%;and the healthy seedling rates of cold-stored seeds decreased from 96.33%-98.00%to 77.33%-97.3%,and the values of the room temperature treatments dropped to 12.00%-68.33%.The germination rates,germination index,healthy seedling rates and seedling heights of the three dragon fruit varieties stored at low temperatures were basically significantly higher than those of the room temperature treatments within 367 d of storage.The germination rates of the three varieties stored at 8℃had no significant differences from other low temperature treatments,but the germination index was significantly lower than other low temperature treatments at 367 d.It showed that low temperature storage at-10-8℃could significantly prolong the vigor and storage time of dragon fruit seeds.Considering cost and other factors,it is better to store dragon fruit seeds in a dry environment at 4℃.The seeds stored at 4℃for 1 year showed a germination rate maintained over 90%and a healthy seedling rate over 85%.
文摘Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). The germination of95 accessions, accounting for 0.51% of the total, declined significantly from above 80% to below 70%. For each crop ofcarrot (Daucus carota var. sativa DC.), lettuce (Lactuca sativa L.), cotton (Gossypium sp. L.), flax (Linum usitatissimumL.) and castor-oil plant (Ricinus communis L.), the mean monitored germination percentage declined significantly as awhole, of which carrot and lettuce seeds lost viability more rapidly. Seed initial germination percentage and pre-storageenvironments affect subsequent seed viability in storage.
文摘Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3).
基金supported by the Ethiopian Institute of Agricultural Research Organization
文摘Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses: modern cold room (5℃), mud house (15℃), concrete block house (17℃ or corrugated iron house (20℃) for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation (p 0.01) in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room (41%) and the mud house (38%) maintained the same level of germination as the intitial germination of the seedlotds (42%). The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots (r 0.80; p 0.01). Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deepphysiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room (5℃) up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level.
基金financially supported by the National Natural Science Foundation of China (41071187 and 40701097)
文摘Two psammophile-dominated Artemisia semi-shrubs (A. wudanica and A. halodendron) and two annual Artemisia forbs (A. sieversiana and A. scoparia) bear significant ecological functions in Horqin Sandy Land, but systematical information on their achenes' germination is very limited. A set of studies were conducted to evaluate seed germination responses to storage periods and methods, different temperatures, lights conditions and sand burial depths, in order to determine inter-specific germination variation in the same genus and to explain how the species adapt to its microhabitat. Fresh achenes of A. wudanica, A. halodendron and A. sieversiana showed high germination capacities, but those of A. scoparia had obvious innate dormancy, which could be broken by chilling and dry storage, especially long-term dry storage. Achene germination of the two semi-shrubs preferred lower temperature fluctuation (10 to 22℃) and was not sensitive to light. But the two annuals preferred higher temperature fluctuation (34 to 22℃) and strong light for their achene germination. These four Artemisia species showed similar responses to sand burial, i.e. soil surface was most favorable for seedling emergence, and the deeper the sand burial, the fewer the seedling emergence. For the two semi-shrubs, their microhabitats are sand dunes with high temperature and intense light, which are not favorable for germination and seedling survival. Only rainfall contributes to temporary decrease of temperature and then triggers germination. We deduced that germination is not the main but a supplementary repro- ductive mode for the two semi-shrubs in sand dunes. For the two annuals, achene germination is the only reproductive mode, but different responses have been developed for microhabitat adaptation. For A. sieversiana, high germination capacities in wide temperature ranges and all light conditions could improve its competition and advancement in the wettest microhabitats. For A. scoparia, obvious innate dormancy of fresh achenes and germination inhabitation under unfavorable conditions are important adaptation to environmental disturbances.
文摘We performed desiccation and storage trials to better understand storage behavior of Knema attenuata seeds. Mature seeds with moisture content (MC) of 31% exhibited 73% germination. During the period of desiccation (open lab condition) seeds with MC 23% showed 40% germination. After further drying to MC 21% germination was reduced to 16%. Complete loss in viability resulted when seed moisture was reduced to 18%. The seeds stored at -10℃, 0℃, 10℃ and 28±2℃ (open lab condition) lost their viability within 10 days. Seeds stored in sealed polythene hags and moist sand retained viability for more days than did seeds stored under all other storage conditions. Sensitivity of seeds to lower temperature and desiccation suggest that the storage behavior of K. attenuata seeds is recalcitrant. Seeds stored in moist conditions can, at best, be stored for a period of two months.
基金Supported by National Key Project of Scientifi c and Technical Supporting Programs of China (2006BAD09B06, 2006BAD03A0308)948 Program of Ministry of Water Resources of China (200207)
文摘In order to enhance the seed storability and supply high-quality seeds for vegetation restoration in the arid and semi-arid regions in Northwest China,the effects of ultra-drying and accelerated aging on the physiological characterstics of Melilotus suaveolens seeds were studied.Melilotus suaveolens seeds were dried in a desiccator containing silica gel to 80,53,42,33,23 and 16 g·kg-1 of moisture contents(MC),respectively.The parameters of the seed quality including germination energy(GE),germination percentage(GP),relative conductivity(RC),dehydrogenase activity(DA) and α-amylase activity(AA) were determined after ultra-drying and accelerated aging.The results showed that ultra-dried seeds with 42 g·kg-1 of MC showed the minimum changes of GE and GP before and after seed aging.Moreover,ultra-dry seeds with 42 g·kg-1 of MC showed higher DA and AA,and lower RC than non-ultra-drying seeds.Therefore,ultra-drying to 42 g·kg-1 of MC was helpful for M.suaveolens seed storage.
基金Funding from National Research Foundation(NRF)of South Africa and South African National Seed Organization(SANSOR)respectively is acknowledged.
文摘Seed storage reserves and organelles after scarification(chemical,mechanical,control)of bambara groundnut with different seed coat colours(cream,light brown and brown)were examined in relation to germination vigour.Seed storage proteins,oil and sugar content,starch granules and protein bodies,germination vigour index(GVI)and mean germination time(MGT)were measured.There were significant(p<0.05)effects of seed scarification on protein body diameter,seed oil content and sugar content.Chemical scarification resulted in seeds having larger starch granules,followed by the control and mechanical scarification that resulted in seeds having smaller starch granules.Mechanical scarification had the highest(p>0.05)protein density,followed by chemical scarification and control seeds that had the lowest protein density.Seeds from the control had the highest oil content,followed by seeds from mechanical scarification and seeds from chemical scarification that had the lowest oil content.Seeds from the control and chemical scarification had larger diameter of protein bodies and sugar content.Seed coat colour significantly(p<0.05)influenced the area and diameter of protein bodies,starch granule area,seed sugar content.Brown seeds produced larger protein bodies and the highest oil content,while light brown seeds had larger area of starch granules and the highest sugar content.Seed storage reserves had an influence on bambara groundnut germination vigour.While favouring dark coloured seeds such as light brown and brown,bambara groundnut seed users should adapt chemical seed scarification to enhance germination vigour of this crop.
文摘We examined the influence of storage time on germinability and tube growth of freeze stored pollens collected from 25 wild male plants in Actinidia eriantha variety. Pollens were stored in freezer at - 20°C for six months and one year periods to determine changing at germinability in time. In vitro germination was conducted in certain cultural medium defined for Actinidia genus. The results showed that the germination percentages and tube lengths of genotypes decreased at the end of storage period. MH22, MH45, MH47, MH56, MH67, MH70, MH71, MH72, MH74, MH55 and MH61 genotypes were evaluated as vigor genotypes, because they maintained their viability and germination capability displaying statistically insignificant decreasing although their tube lengths significantly decreased except MH67. This investigation provided to determine some robust wild male germplasm resources in A. eriantha in point of durability of pollens against long term conservation for using at future pollination and breeding programs.