The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Ni...The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith)) leaf disks. We compared the effect of temperatures ranging from 15°C, 18°C, 20°C, 22°C to 25°C on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli. The highest average of GUS activity was obtained at 20°C among the five temperatures tested although the difference between the 18°C and 20°C treatment was not statistically significant. The GUS activity at 15°C was statistically lower than those at 18°C and 20°C. The GUS activity in 22°C treatment was an intermediate between the highest (18/20°C) and second highest averages (15°C), and was not statistically significantly different. The lowest average of GUS activity was observed at 25°C. The highest increase in the plate average of fresh weight yield was obtained at 20°C among the five temperature tested. The 20°C treatment was statistically significantly better than the 15°C and 18°C treatments. The 20°C co-cultivation treatment resulted in the higher FW yield than 22°C and 25°C even though the differences were not statistically significant. In conclusion, low co-cultivation temperature at 20°C resulted in the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.展开更多
At present, chlorine dioxide has been widely used as a bactericide that may become an alternative to chlorine. In this study, fresh-cut narrow-leaf cattail was soaked with 45, 70 and 95 mg/L chlorine dioxide solution,...At present, chlorine dioxide has been widely used as a bactericide that may become an alternative to chlorine. In this study, fresh-cut narrow-leaf cattail was soaked with 45, 70 and 95 mg/L chlorine dioxide solution, respectively. Fresh-cut narrow-leaf cattail samples were collected regularly to determine changes in surface microbe amount, cellulose content, Vc content, reduction sugar content and sensory quality of narrow-leaf cattail, thus analyzing the effects of chlorine diox- ide on sterilization and preservation of fresh-cut narrow-leaf cattail. The results showed that all three concentrations of chlorine dioxide solution could significantly reduce the amount of microbes on the surface of fresh-cut narrow-leaf cattail and improve the edible safety of products. The initial sterilization efficiency was im- proved gradually as the concentration of chlorine dioxide increased. In addition, chlorine dioxide treatment postponed the increase of cellulose content of fresh-cut narrow-leaf cattail. However, chlorine dioxide oxidized Vc and reducing sugar, and its bleaching effect also exerted a certain impact on the sensory quality of fresh- cut narrow-leaf cattail. Based on comprehensive comparisons, 45 - 70 mg/L chlorine dioxide solution exerted the best effects on sterilization and preservation of fresh-cut narrow-leaf cattail. This study laid the foundation for the production and application of chlorine dioxide solution and promotion of rapid development of nar- row-leaf cattail industry.展开更多
This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of bi...This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of biogas production facility in some villages of local tobacco area,this paper selects Longwan Village of Fengshiyan Town as the experimental site and explores the rational way of discarded fresh tobacco leaf biogas fermentation. Results show that cutting and fermentation of discarded fresh tobacco leaf before adding into biogas digester is conductive to improving p H in fermentation process,reducing crust amount,and effectively improving biogas production amount and rate. The study can provide reference for effective processing and rational utilization of discarded fresh tobacco leaf.展开更多
In order to reveal the cold resistant mechanism of tea plant,two varieties with different cold resistances were studied.The activities of catalase(CAT),peroxidase(POD),superoxide dismutase(SOD) and polyphenol oxidase(...In order to reveal the cold resistant mechanism of tea plant,two varieties with different cold resistances were studied.The activities of catalase(CAT),peroxidase(POD),superoxide dismutase(SOD) and polyphenol oxidase(PPO) were investigated,and the contents of soluble protein,sugar and malondialdehyde(MDA) were determined in fresh tea leaves in the autumn.The results showed that the activities of POD and the content of soluble sugar were both much higher in the variety with strong cold resistance,and the content of soluble protein was associated with the cold resistance,while the cold resistance of the plant was not related with the activities of the CAT,SOD and PPO,and the content of MDA.It is considered that the activity of POD and contents of soluble sugar could be used as indicators to identify the cold resistance of tea varieties.展开更多
The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Pro...The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Progressive pruning is an oil palm pruning method in which pruning is done at the same time as fresh fruit bunch harvesting. This study evaluated the impact of progressive pruning on leaf miner population in oil palm and how these two factors (leaf miner and progressive pruning) affect the yield of oil palm at the Benso Oil Palm Plantation Public listed company (BOPP. Plc). Five distinct blocks in the plantation were selected for observations on fronds at various ranks (33, 25, or 17) based on the degree of defoliation by counting the number of pests on leaflets at different phases of insect development. Fronds from selected plots were sampled in a Completely Randomized Design (CRD). The size of plots used for the study ranged between 19 to 45 hectares. A minimum of 78 fronds were evenly cut from each block for pest count depending on the block size. Secondary data on annual yields of fresh fruit bunches before and after the introduction of progressive pruning were also obtained from BOPP. Plc records from 2011-2020. The results from the analyzed data on leaf miner index before and after the introduction of progressive pruning showed that progressive pruning has, to a high extent (64% to 36%), reduced leaf miner populations in the plantation. Paired t-test on fresh fruit bunch yield has also revealed a significant (p < 0.001) increase in annual fresh fruit bunch yield due to progressive pruning. A regression analysis, however, revealed a lower rate of yield loss (3.05 to 2.70 tonnes) to leaf miner infestation after the introduction of progressive pruning. The study recommends progressive pruning as a key cultural practice for improving crop yields in leaf miner prone plantations.展开更多
文摘The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith)) leaf disks. We compared the effect of temperatures ranging from 15°C, 18°C, 20°C, 22°C to 25°C on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli. The highest average of GUS activity was obtained at 20°C among the five temperatures tested although the difference between the 18°C and 20°C treatment was not statistically significant. The GUS activity at 15°C was statistically lower than those at 18°C and 20°C. The GUS activity in 22°C treatment was an intermediate between the highest (18/20°C) and second highest averages (15°C), and was not statistically significantly different. The lowest average of GUS activity was observed at 25°C. The highest increase in the plate average of fresh weight yield was obtained at 20°C among the five temperature tested. The 20°C treatment was statistically significantly better than the 15°C and 18°C treatments. The 20°C co-cultivation treatment resulted in the higher FW yield than 22°C and 25°C even though the differences were not statistically significant. In conclusion, low co-cultivation temperature at 20°C resulted in the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.
基金Supported by Practice and Innovation Training Project for College Students in Jiangsu Province(2012JSSPITP3590)
文摘At present, chlorine dioxide has been widely used as a bactericide that may become an alternative to chlorine. In this study, fresh-cut narrow-leaf cattail was soaked with 45, 70 and 95 mg/L chlorine dioxide solution, respectively. Fresh-cut narrow-leaf cattail samples were collected regularly to determine changes in surface microbe amount, cellulose content, Vc content, reduction sugar content and sensory quality of narrow-leaf cattail, thus analyzing the effects of chlorine diox- ide on sterilization and preservation of fresh-cut narrow-leaf cattail. The results showed that all three concentrations of chlorine dioxide solution could significantly reduce the amount of microbes on the surface of fresh-cut narrow-leaf cattail and improve the edible safety of products. The initial sterilization efficiency was im- proved gradually as the concentration of chlorine dioxide increased. In addition, chlorine dioxide treatment postponed the increase of cellulose content of fresh-cut narrow-leaf cattail. However, chlorine dioxide oxidized Vc and reducing sugar, and its bleaching effect also exerted a certain impact on the sensory quality of fresh- cut narrow-leaf cattail. Based on comprehensive comparisons, 45 - 70 mg/L chlorine dioxide solution exerted the best effects on sterilization and preservation of fresh-cut narrow-leaf cattail. This study laid the foundation for the production and application of chlorine dioxide solution and promotion of rapid development of nar- row-leaf cattail industry.
文摘This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of biogas production facility in some villages of local tobacco area,this paper selects Longwan Village of Fengshiyan Town as the experimental site and explores the rational way of discarded fresh tobacco leaf biogas fermentation. Results show that cutting and fermentation of discarded fresh tobacco leaf before adding into biogas digester is conductive to improving p H in fermentation process,reducing crust amount,and effectively improving biogas production amount and rate. The study can provide reference for effective processing and rational utilization of discarded fresh tobacco leaf.
文摘In order to reveal the cold resistant mechanism of tea plant,two varieties with different cold resistances were studied.The activities of catalase(CAT),peroxidase(POD),superoxide dismutase(SOD) and polyphenol oxidase(PPO) were investigated,and the contents of soluble protein,sugar and malondialdehyde(MDA) were determined in fresh tea leaves in the autumn.The results showed that the activities of POD and the content of soluble sugar were both much higher in the variety with strong cold resistance,and the content of soluble protein was associated with the cold resistance,while the cold resistance of the plant was not related with the activities of the CAT,SOD and PPO,and the content of MDA.It is considered that the activity of POD and contents of soluble sugar could be used as indicators to identify the cold resistance of tea varieties.
文摘The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Progressive pruning is an oil palm pruning method in which pruning is done at the same time as fresh fruit bunch harvesting. This study evaluated the impact of progressive pruning on leaf miner population in oil palm and how these two factors (leaf miner and progressive pruning) affect the yield of oil palm at the Benso Oil Palm Plantation Public listed company (BOPP. Plc). Five distinct blocks in the plantation were selected for observations on fronds at various ranks (33, 25, or 17) based on the degree of defoliation by counting the number of pests on leaflets at different phases of insect development. Fronds from selected plots were sampled in a Completely Randomized Design (CRD). The size of plots used for the study ranged between 19 to 45 hectares. A minimum of 78 fronds were evenly cut from each block for pest count depending on the block size. Secondary data on annual yields of fresh fruit bunches before and after the introduction of progressive pruning were also obtained from BOPP. Plc records from 2011-2020. The results from the analyzed data on leaf miner index before and after the introduction of progressive pruning showed that progressive pruning has, to a high extent (64% to 36%), reduced leaf miner populations in the plantation. Paired t-test on fresh fruit bunch yield has also revealed a significant (p < 0.001) increase in annual fresh fruit bunch yield due to progressive pruning. A regression analysis, however, revealed a lower rate of yield loss (3.05 to 2.70 tonnes) to leaf miner infestation after the introduction of progressive pruning. The study recommends progressive pruning as a key cultural practice for improving crop yields in leaf miner prone plantations.
