Revegetation of disturbed land, particularly in arid environment, is often hindered by low seedling establishment. Information on seed biology and germination cues of valuable species is lacking. We investigated seed ...Revegetation of disturbed land, particularly in arid environment, is often hindered by low seedling establishment. Information on seed biology and germination cues of valuable species is lacking. We investigated seed germination of two Acacia species （Acacia tortilis （Forsk.） Hayne and Acacia oerfota （Forssk） schwein/）, required for nitrogen fixation and rehabilitation of arid and semi-arid areas.（four pregermination seed treatments were applied in order to find the best treatment in germinating acacia species. The medium was L2 and three replicates were used. Seeds pretreated with sand paper and also with H2SO4 and then H2O2 had the highest germination percentage in both species. The lowest germination percentage resulted from soaking seeds in water for 48 h followed by soaking in H2SO4 for A. oerfota and from soaking in water for 24 h for A. tortilis. Because the use of sand paper is difficult and time consuming, we recommend pretreatment ofA. tortilis and A. oerfota seeds with H2SO4 and H2O2 before planting. Our study results are significant for conservation agencies with an interest in optimizing germination in arid zones for rehabilitation and reforestation.展开更多
Lophira lanceolata is a multi-purpose woody plant species used by local populations in Benin. Its seeds are used for the manufacture of edible vegetable oil and also for medicinal care. However, reproduction by seed o...Lophira lanceolata is a multi-purpose woody plant species used by local populations in Benin. Its seeds are used for the manufacture of edible vegetable oil and also for medicinal care. However, reproduction by seed of this plant species is compromised not only by the multiple uses made of the seeds, but also by the difficulties of germination in the natural environment. Several ecological factors could explain this difficulty of germination. In this study, we investigated the species seeds ecophysiology in order to develop seedlings production techniques for its reintroduction. Beta regression was performed to test the effect of water, light and provenance on seeds germination rate. The germination speed was expressed as the median germination time. The results showed that the germination rate was better under light conditions (β = 0.77674 ± 0.14954, Z = 5.194, p < 0.0000). The germination rate decreased as the frequency of watering increased (β = -0.28222 ± 0.14809, Z = -1.906, p = 0.0567). The best provenance was the phytodistrict of Atacora chain. The cumulative germination rate reached 50% after 54 days for seeds collected from Atacora chain and after 57 days under light conditions. Regarding the level of watering, the germination rate remained below 50% regardless the treatment. The germination speed was higher for seeds collected from Atacora chain and that have germinated under light conditions and watered twice a week. For the sustainable management of L. lanceolata, domestication by establishment of plantations by rural communities is recommended based on seeds from Atacora chain.展开更多
Low germination and vigor of rice seed associated with dry-seed broadcasting are common problems encountered by rice growers.The objectives of this study were to evaluate the role of potassium nitrate（KNO3）on the pa...Low germination and vigor of rice seed associated with dry-seed broadcasting are common problems encountered by rice growers.The objectives of this study were to evaluate the role of potassium nitrate（KNO3）on the pattern of seed imbibition and to determine the effect of seed priming with KNO3 on the germination percentage,speed and uniformity of germination in rice seed.Experiment 1 compared the patterns of seed imbibition of six concentrations of KNO3（0,0.25,0.50,1.00,1.50,and 2.00%）in two rice cultivars-KDML105 and RD15.The results showed that soaking rice seed in KNO3 at higher concentrations could delay the imbibition time.The higher concentrations of KNO3 delayed the imbibition time of rice seed and took a longer time to reach the end of phases 1 and 2 compared to the lower concentrations.The patterns of seed imbibition using distilled water of both rice cultivars（KDML105 and RD15）were quite similar,but with different concentrations of KNO3,the imbibition time taken to reach the end of phases 1 and 2 was slightly postponed in KDML105 suggesting that different rice cultivars may need different imbibition times for soaking seed in the priming process.Experiment 2 evaluated the effects of seed priming with 1.0 and 2.0%KNO3 at different imbibition times.It was found that priming with 1.0%KNO3 showed better seed germination than priming with 2.0%KNO3 and seed priming with 1.0%KNO3 at the imbibition time of early phase 2（or 28 h for KDML105）improved seed germination and increased both the speed and uniformity of seed germination.The results of this study show promise for the use of priming with 1.0%KNO3 soaked until early phase 2 of seed imbibition for improving the seed germination and vigor of rice in dry seed broadcasting.展开更多
文摘Revegetation of disturbed land, particularly in arid environment, is often hindered by low seedling establishment. Information on seed biology and germination cues of valuable species is lacking. We investigated seed germination of two Acacia species （Acacia tortilis （Forsk.） Hayne and Acacia oerfota （Forssk） schwein/）, required for nitrogen fixation and rehabilitation of arid and semi-arid areas.（four pregermination seed treatments were applied in order to find the best treatment in germinating acacia species. The medium was L2 and three replicates were used. Seeds pretreated with sand paper and also with H2SO4 and then H2O2 had the highest germination percentage in both species. The lowest germination percentage resulted from soaking seeds in water for 48 h followed by soaking in H2SO4 for A. oerfota and from soaking in water for 24 h for A. tortilis. Because the use of sand paper is difficult and time consuming, we recommend pretreatment ofA. tortilis and A. oerfota seeds with H2SO4 and H2O2 before planting. Our study results are significant for conservation agencies with an interest in optimizing germination in arid zones for rehabilitation and reforestation.
文摘Lophira lanceolata is a multi-purpose woody plant species used by local populations in Benin. Its seeds are used for the manufacture of edible vegetable oil and also for medicinal care. However, reproduction by seed of this plant species is compromised not only by the multiple uses made of the seeds, but also by the difficulties of germination in the natural environment. Several ecological factors could explain this difficulty of germination. In this study, we investigated the species seeds ecophysiology in order to develop seedlings production techniques for its reintroduction. Beta regression was performed to test the effect of water, light and provenance on seeds germination rate. The germination speed was expressed as the median germination time. The results showed that the germination rate was better under light conditions (β = 0.77674 ± 0.14954, Z = 5.194, p < 0.0000). The germination rate decreased as the frequency of watering increased (β = -0.28222 ± 0.14809, Z = -1.906, p = 0.0567). The best provenance was the phytodistrict of Atacora chain. The cumulative germination rate reached 50% after 54 days for seeds collected from Atacora chain and after 57 days under light conditions. Regarding the level of watering, the germination rate remained below 50% regardless the treatment. The germination speed was higher for seeds collected from Atacora chain and that have germinated under light conditions and watered twice a week. For the sustainable management of L. lanceolata, domestication by establishment of plantations by rural communities is recommended based on seeds from Atacora chain.
基金financially supported by a Kasetsart University 72 Year Anniversary Graduate Scholarship, from the Graduate School, Kasetsart University, Thailand
文摘Low germination and vigor of rice seed associated with dry-seed broadcasting are common problems encountered by rice growers.The objectives of this study were to evaluate the role of potassium nitrate（KNO3）on the pattern of seed imbibition and to determine the effect of seed priming with KNO3 on the germination percentage,speed and uniformity of germination in rice seed.Experiment 1 compared the patterns of seed imbibition of six concentrations of KNO3（0,0.25,0.50,1.00,1.50,and 2.00%）in two rice cultivars-KDML105 and RD15.The results showed that soaking rice seed in KNO3 at higher concentrations could delay the imbibition time.The higher concentrations of KNO3 delayed the imbibition time of rice seed and took a longer time to reach the end of phases 1 and 2 compared to the lower concentrations.The patterns of seed imbibition using distilled water of both rice cultivars（KDML105 and RD15）were quite similar,but with different concentrations of KNO3,the imbibition time taken to reach the end of phases 1 and 2 was slightly postponed in KDML105 suggesting that different rice cultivars may need different imbibition times for soaking seed in the priming process.Experiment 2 evaluated the effects of seed priming with 1.0 and 2.0%KNO3 at different imbibition times.It was found that priming with 1.0%KNO3 showed better seed germination than priming with 2.0%KNO3 and seed priming with 1.0%KNO3 at the imbibition time of early phase 2（or 28 h for KDML105）improved seed germination and increased both the speed and uniformity of seed germination.The results of this study show promise for the use of priming with 1.0%KNO3 soaked until early phase 2 of seed imbibition for improving the seed germination and vigor of rice in dry seed broadcasting.
