Using early indica rice Zhongzao 39 and japonica rice Xiushui 134 as the experimental materials, the effects of 4 temperature levels after transplantation on turning green, leaf growth, tillering, dry matter accumulat...Using early indica rice Zhongzao 39 and japonica rice Xiushui 134 as the experimental materials, the effects of 4 temperature levels after transplantation on turning green, leaf growth, tillering, dry matter accumulation and nutrition absorption were studied using a greenhouse and an artificial climate chest. We found that （1） tillering did not occur and growth of one new leaf took over 15 days at 16℃. New leaf growth took over 10 days and tillering occurred after 15 days of transplanta- tion at 19 ℃. Tillering appeared 10 days after planting and new leaf growth took 5 days between 22 and 25 ℃. This showed that low temperature impeded the turn- ing green of rice seedlings and the temperature must reach above 19 ℃ to ensure timely appearance of new leaf, tillering and turning green in rice seedlings. （2） When the temperature was 10 increased, both 100-seedling dry weight and nitrogen absorption increased. At temperatures lower 11 than 19 ℃, both dry weight incre- ment and nitrogen absorption were low. Nitrogen absorption of all organs increased obviously between 19 and 22 ℃. Thus, 19 ℃ was found to be an minimum tem- perature for plant organs to absorb nutrients. （3）Tiller of seedling cultivated on dry- land soil and substrate grew quickly and tillering occurred about 7 days after trans- planting. After that, the growth rate was about 0.18 tiller per day. For seedlings cultivated in slurry, tillering occurred 10 days after transplanting and the tillers grew at a rate of 0.16 tiller per day. However, substrate choice during the seedling rais- ing stage had no significant influence on leaf age. （4） Japonica rice exhibited stronger resistance to low temperature than indica rice. Tillering began at about the same time after transplanting in both rice varieties, but japonica rice exhibited higher tillering speed than early indica rice. The speed of leaf growth was higher in japoni- ca rice before transplantation but higher in indica rice after transplantation.展开更多
In this study, wild rice chromosome segment substitution lines bred by Yuanjiang common wild rice and elite indica rice variety Teqing were used as ex-perimental materials to detect aluminum tolerancerelated QTLs base...In this study, wild rice chromosome segment substitution lines bred by Yuanjiang common wild rice and elite indica rice variety Teqing were used as ex-perimental materials to detect aluminum tolerancerelated QTLs based on the phe-notypic data of indoor and outdoor plant height inhibition rate and dry weight inhibi-tion rate at seedling stage. According to experimental results, 11, 18, 14 and 5 QTLs related with aluminum tolerance were detected respectively on different chro-mosomes. Analysis of phenotypic data of indoor and outdoor plant height inhibition rate indicated that QTLs around RM38 on chromosome 8 and RM277 chromosome 12 exhibited the highest contribution rates （12% and 11%）, belonging to major QTLs. Analysis of phenotypic data of indoor and outdoor dry weight inhibition rate indicated that the highest contribution rate was only 9% and 8%; therefore, no major QTL was detected. QTLs detected repeatedly were located on chromosomes 7, 8, 9, 11 and 12, respectively. Two QTLs were located on chromosome 8. QTLs around RM310 were detected three times and other QTLs were detected twice, which were identified as stable QTLs.展开更多
[ Objective] The study was to compare the structural and moisture characteristics of leaf from the plantlets of three types of omamental lily（ Lilium brownii）. [ Method ] The paraffin sections of leaves of tested li...[ Objective] The study was to compare the structural and moisture characteristics of leaf from the plantlets of three types of omamental lily（ Lilium brownii）. [ Method ] The paraffin sections of leaves of tested lily varieties were prepared and then observed under microscope, and the stomatal characteristics and moisture characteristics of tested lily varieties were measured. I Resaltl All the three ornamental lily varieties show isobilateral leaf, single layer of epicuticula and lower epidermis, and no obvious differentiation of palisade tissue and spongy tissue; their stomata distribute in lower epidermis, and the guard cells are dumbbell-shaped; all of these matedais present high moisture. For the leaf sick- ness, midrib sickness and mesophyll tissue sickness, the order was determined to be oriental lily 〉 Lilium/ongiflorum 〉 Asian lily; of the three types of ornamental lily, Ulium Iongiflorum has the largest stomatai aperture and Asian lily has the smallest; focusing the water potential and moisture, the turn was Asian lily 〉 oriental lily 〉 Lilium Iong＇fflorum. [ Condusion] The study may facilitate the artificial regulation of the growth conditions of the plantlets of ornamental lily.展开更多
Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem （Population - I）, Upper Shillong （Population - II）, Shillo...Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem （Population - I）, Upper Shillong （Population - II）, Shillong Peak （Population -III）, Laitkor （Population - IV） and Nongpiyur （Population - V） to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions （full sunlight （100%）, intermediate sunlight （50%） and low sunlight （30%）） showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees （〉Scm dbh） exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species.展开更多
In our trials, from 2007 to 2008, of mass production of seedlings of Hizikiafusiformis using synchronization techniques, problems of a ＂dark thalli＂ phenomenon and epiphytes contamination severely threatened the hea...In our trials, from 2007 to 2008, of mass production of seedlings of Hizikiafusiformis using synchronization techniques, problems of a ＂dark thalli＂ phenomenon and epiphytes contamination severely threatened the health of juvenile seedlings. In this investigation, we optimized conditions for improving the growth of juvenile seedlings. Seven string collectors were seeded with zygotes and a series of experiments were conducted including direct exposure to solar irradiance, co-culture with Ulva spp. and treatment with sodium hypochlorite. It was found that direct exposure to solar irradiance （maximum： 1 740 μmol photons/（m2.s）） for 2 h per day could efficiently enhance the growth of young seedlings and simultaneously inhibit the growth of epiphytic algae. In this treatment, 50-day old seedlings could reach an average of 0.44 cm in length and possess up to nine leaflets. However, a single treatment with 18-mmol/L sodium hypochlorite for 10 rain severely harmed 15-day old seedlings. In comparison, weekly treatment with 2.2-mmol/L sodium hypochlorite for 10 rain brought no apparent harm to seedlings and eliminated epiphytic algae efficiently. However, this treatment significantly increased the detachment rate of seedlings, Inoculating Ulva spp. onto the collector caused a dramatic decrease in the number of seedlings. However, the growth of the remaining seedlings appeared unhampered. All collectors except the control were daily sprayed with a high pressure water jet from the 84 day post fertilization. From the first day to 50th day, no ＂dark thallus＂ was observed on any of the seven collectors. We believe that well-timed daily exposure to solar irradiance would favor H. fusiformis in its early growing stages.展开更多
基金Supported by Special Scientific Research Funds for Commonweal Section(Agriculture)(201203029,201003016)China Rice Industry System Project(2011-2015)Special Funding for Basic Scientific Research and Zhejiang Provincial Natural Science Foundation(LY13C130004)~~
文摘Using early indica rice Zhongzao 39 and japonica rice Xiushui 134 as the experimental materials, the effects of 4 temperature levels after transplantation on turning green, leaf growth, tillering, dry matter accumulation and nutrition absorption were studied using a greenhouse and an artificial climate chest. We found that （1） tillering did not occur and growth of one new leaf took over 15 days at 16℃. New leaf growth took over 10 days and tillering occurred after 15 days of transplanta- tion at 19 ℃. Tillering appeared 10 days after planting and new leaf growth took 5 days between 22 and 25 ℃. This showed that low temperature impeded the turn- ing green of rice seedlings and the temperature must reach above 19 ℃ to ensure timely appearance of new leaf, tillering and turning green in rice seedlings. （2） When the temperature was 10 increased, both 100-seedling dry weight and nitrogen absorption increased. At temperatures lower 11 than 19 ℃, both dry weight incre- ment and nitrogen absorption were low. Nitrogen absorption of all organs increased obviously between 19 and 22 ℃. Thus, 19 ℃ was found to be an minimum tem- perature for plant organs to absorb nutrients. （3）Tiller of seedling cultivated on dry- land soil and substrate grew quickly and tillering occurred about 7 days after trans- planting. After that, the growth rate was about 0.18 tiller per day. For seedlings cultivated in slurry, tillering occurred 10 days after transplanting and the tillers grew at a rate of 0.16 tiller per day. However, substrate choice during the seedling rais- ing stage had no significant influence on leaf age. （4） Japonica rice exhibited stronger resistance to low temperature than indica rice. Tillering began at about the same time after transplanting in both rice varieties, but japonica rice exhibited higher tillering speed than early indica rice. The speed of leaf growth was higher in japoni- ca rice before transplantation but higher in indica rice after transplantation.
基金Supported by National Natural Science Foundation of China(30771340,30771156,31071412)~~
文摘In this study, wild rice chromosome segment substitution lines bred by Yuanjiang common wild rice and elite indica rice variety Teqing were used as ex-perimental materials to detect aluminum tolerancerelated QTLs based on the phe-notypic data of indoor and outdoor plant height inhibition rate and dry weight inhibi-tion rate at seedling stage. According to experimental results, 11, 18, 14 and 5 QTLs related with aluminum tolerance were detected respectively on different chro-mosomes. Analysis of phenotypic data of indoor and outdoor plant height inhibition rate indicated that QTLs around RM38 on chromosome 8 and RM277 chromosome 12 exhibited the highest contribution rates （12% and 11%）, belonging to major QTLs. Analysis of phenotypic data of indoor and outdoor dry weight inhibition rate indicated that the highest contribution rate was only 9% and 8%; therefore, no major QTL was detected. QTLs detected repeatedly were located on chromosomes 7, 8, 9, 11 and 12, respectively. Two QTLs were located on chromosome 8. QTLs around RM310 were detected three times and other QTLs were detected twice, which were identified as stable QTLs.
文摘[ Objective] The study was to compare the structural and moisture characteristics of leaf from the plantlets of three types of omamental lily（ Lilium brownii）. [ Method ] The paraffin sections of leaves of tested lily varieties were prepared and then observed under microscope, and the stomatal characteristics and moisture characteristics of tested lily varieties were measured. I Resaltl All the three ornamental lily varieties show isobilateral leaf, single layer of epicuticula and lower epidermis, and no obvious differentiation of palisade tissue and spongy tissue; their stomata distribute in lower epidermis, and the guard cells are dumbbell-shaped; all of these matedais present high moisture. For the leaf sick- ness, midrib sickness and mesophyll tissue sickness, the order was determined to be oriental lily 〉 Lilium/ongiflorum 〉 Asian lily; of the three types of ornamental lily, Ulium Iongiflorum has the largest stomatai aperture and Asian lily has the smallest; focusing the water potential and moisture, the turn was Asian lily 〉 oriental lily 〉 Lilium Iong＇fflorum. [ Condusion] The study may facilitate the artificial regulation of the growth conditions of the plantlets of ornamental lily.
文摘Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem （Population - I）, Upper Shillong （Population - II）, Shillong Peak （Population -III）, Laitkor （Population - IV） and Nongpiyur （Population - V） to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions （full sunlight （100%）, intermediate sunlight （50%） and low sunlight （30%）） showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees （〉Scm dbh） exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (Nos. 2006AA10A412 2006AA10A416)+1 种基金Main Program of National Science Infrastructure Platform, a project from the Ministry of Science and Technology of China (No. 2006DKA30470-017)a non-profit program from the Ministry of Agriculture of China (No. 200903030)
文摘In our trials, from 2007 to 2008, of mass production of seedlings of Hizikiafusiformis using synchronization techniques, problems of a ＂dark thalli＂ phenomenon and epiphytes contamination severely threatened the health of juvenile seedlings. In this investigation, we optimized conditions for improving the growth of juvenile seedlings. Seven string collectors were seeded with zygotes and a series of experiments were conducted including direct exposure to solar irradiance, co-culture with Ulva spp. and treatment with sodium hypochlorite. It was found that direct exposure to solar irradiance （maximum： 1 740 μmol photons/（m2.s）） for 2 h per day could efficiently enhance the growth of young seedlings and simultaneously inhibit the growth of epiphytic algae. In this treatment, 50-day old seedlings could reach an average of 0.44 cm in length and possess up to nine leaflets. However, a single treatment with 18-mmol/L sodium hypochlorite for 10 rain severely harmed 15-day old seedlings. In comparison, weekly treatment with 2.2-mmol/L sodium hypochlorite for 10 rain brought no apparent harm to seedlings and eliminated epiphytic algae efficiently. However, this treatment significantly increased the detachment rate of seedlings, Inoculating Ulva spp. onto the collector caused a dramatic decrease in the number of seedlings. However, the growth of the remaining seedlings appeared unhampered. All collectors except the control were daily sprayed with a high pressure water jet from the 84 day post fertilization. From the first day to 50th day, no ＂dark thallus＂ was observed on any of the seven collectors. We believe that well-timed daily exposure to solar irradiance would favor H. fusiformis in its early growing stages.
