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1.
香蕉叶片组织细胞结构特性与耐寒性的关系   总被引:4,自引:0,他引:4  
对广东目前推广的4个香蕉良种以及粉蕉和大蕉进行切片显微观察,并结合低温处理的电导率测定,结果表明,香蕉叶片组织细胞结构紧密度(CTR值)与品种的耐寒性密切相关,且具有相对的稳定性,可作为香蕉耐寒性的鉴定指标,供试品种耐寒力强弱依次为粉蕉、大蕉、威廉斯(8818)、“巴西”、“93-1”、广东二号(63-1)。  相似文献   

2.
从香蕉(Musa AAA)组织培养繁殖后代中,选育出特长果指香蕉新品系“93-1”,主要特点为植株表现中矮秆(216 cm),茎粗中等(67.1 cm),苗期叶色浓绿,叶形椭圆形,叶形比(长/宽)1.91,叶尖急尖,叶基凹陷呈耳垂状;果穗7~12梳,平均8.07梳/穗,穗长81.6 cm,单穗重22.8 kg,单果重213.5 g,果指数123.4条/穗,果指特长(25.8 cm);可溶性固形物含量21.8%;全生育期321d(春植)至368 d(夏植),约44片叶。“93-1”适宜在广东雷州半岛及海南岛栽培种植。  相似文献   

3.
从香蕉(Musa AAA)组织培养繁殖后代中,选育出特长果指香蕉新品系“93-1”,主要特点为植株表现中矮秆(216cm),茎粗中等(67.1cm),苗期叶色浓绿,叶形椭圆形,叶形比(长/宽)1.91,叶尖急尖,叶基凹陷呈耳垂状;果穗7-12梳,平均8.07梳/穗,穗长81.6cm,单穗重22.8kg,单果重213.5g,果指数123.4条/穗,果指特长(25+8cm);可溶性固形物含量21.8%;全生育期321d(春植)至368d(夏植),约44片叶。“93—1”适宜在广东雷州半岛及海南岛栽培种植。  相似文献   

4.
以粉蕉的吸芽为试材 ,进行了离体快速繁殖研究 ,结果表明 :以改良MS +BA4 .0mg/L(单位下同 ) +AD5.0 +NAA0 .1作诱导培养基 ,外植体褐变率低 ,芽的诱导率高 ,且芽的生长良好 ;以改良MS +BA3- 6 +NAA0 .1为继代培养基 ,可以获得较高的不定芽增殖率 ,在增殖过程中 ,给予一定的低温处理和变化调整BA的用量 ,可以保持较高的增殖率 (2 .6倍以上 ) ,而且芽的长势好 ;生根培养以 1/ 2MS +IBA1.0 +NAA0 .2 +AC1为宜。  相似文献   

5.
寻氏肌蛤 Museulus senhousei(Benson),福建俗称“海(虫间)”、“土鬼”或“乌(虫念)”,广东称为“薄壳”。它广泛地分布在我国南北沿岸,肉供食用,并可作农肥和饲料。在沿海一带,以往把寻氏肌蛤列为野生贝类,关于它的养殖和利用,仅局限于福建和广东两省的部分地区,没有引起普遍的重视。寻氏肌蛤资源丰富,产量高,生产周期短,养殖方法简易,是一种值得发展养殖的新品种。为了充分利用贝类资源,扩大养殖  相似文献   

6.
以粉蕉的吸芽为试材,进行了离体快速繁殖研究,结果表明:以改良MS BA4.0mg/L(单位下同) AD5.0 NAA0.1作诱导培养基,外植体褐变率低,芽的诱导率高,且芽的生长良好;以改良MS BA3-6 NAA0.1为继代培养基,可以获得较高的不定芽增殖率,在增殖过程中,给予一定的低温处理和变化调整BA的用量,可以保持较高的增殖率(2.6倍以上),而且芽的长势好;生根培养以1/2MS IBA1.0 NAA0.2 ACl为宜。  相似文献   

7.
为了解广东沿海 Cu含量水平的时空变化趋势 ,1989~ 1997年实施“南海贻贝观察”对广东沿海 12个地点进行了连续监测。实测数据和有关历史资料综合分析结果显示 ,广东沿海牡蛎体 Cu含量(湿重 )范围为 2 .70~ 352 mg· kg-1,平均值为 94 .1mg·kg-1,总超标率达 35.1% ;局部海区属重污染水平。牡蛎体 Cu含量的空间分布特点呈珠江口海区 >粤西海区 >粤东海区格局 ;Spearman顺位相关分析结果表明 ,1989~ 1997年间 ,广东沿海牡蛎体 Cu含量年际间无明显的趋势性变化。  相似文献   

8.
利用扩展的线性支出系统(ELES),依据1997年及2003年广东省城镇居民年人均可支配收入和消费支出的截面数据,对广东城镇居民消费结构的变动情况进行定量分析。分析结果表明,广东城镇居民在“衣”和“食”得到满足之余,越来越重视对“住”与“行”的消费,同时,对精神文化、教育、交往联络、自身健康和保健也越来越关注,并提出了促进广东城镇居民消费结构优化和升级的几点建议。  相似文献   

9.
由中国测绘学会主办的全国首届“优秀测绘期刊奖”于6月26日在西宁揭晓。首届“优秀测绘期刊奖”设一、二、三等奖,其中一等奖8名,二等奖12名,三等奖12名。《大地测量与地球动力学》荣获一等奖(表1)。表1一等奖编号期刊名称主办单位2007-4-1-1《测绘学报》中国测绘学会2007-4-1  相似文献   

10.
1GIGANTICRING-MORPHOSTRUCTURESOFAMUR-SONGHUA-HUANGHELINEAMENT(ASHL)Thereareaseriesofgiganticring-morphostructure(RM)alongthemarginofcontinentwithdiameterfrom1-2to3-4thousandkilometers.ASHLcrossthenextmega-RMontheeasternmarginofAsia:Amur,Korean,EastChinaandtheSeaofOkhotsk.TheAmurmega-RMismorethan2500kmindiameterandcoversthewholebasinoftheAmurRiveraswellasseriesofsmallbasinsconnectedwiththeSeasofOkhotskandJapan.Theconformaldistributionofthe“steps”ofthicknessear…  相似文献   

11.
Analysis of cold tolerance on mangroveKandelia candel leaf growing in different soil salinity along Jiulong River Estuary in South China showed that the cold tolerance decreased as the increase of soil salinity. The lethal temperatures ofK. candel leaf were −10.4, −9.9 and −8.6 °C in Liaodong, Baijiao and Aotou, respectively. Under 1–2°C cold stress treatment on detached leaves ofK. candel, their caloric value gradually decreased, while electrolyte leakage gradually increased. The leaf's caloric value and electrolyte leakage in Aotou with higher soil salinity varied more largely than those in Liaodong with lower soil salinity. InK. candel leaf, total water content lowered a little, bound water content rose significantly and free water content dropped significantly with duration of cold stress. At the same time, reduction sugar, soluble sugar and starch content gradually decreased and sucrose content gradually increased. Bound water, free water and sucrose content inK. candel leaf from Aotou with higher soil salinity changed more slowly than those from Liaodong with lower soil salinity, but reduction sugar, soluble sugar and starch content inK. candel leaf from Aotou had faster variations than those from Liaodong. These data indicated that soil salinity can reduce cold tolerance ofK. candel leaf by increasing negative effect of salt ions in cell membrane, inhibiting variations of water content, and aggravating consumption of material and energy. Supported by the Found for Outstanding Young Teacher, the Ministry of Education, China.  相似文献   

12.
CLIMATIC VARIATIONS IN CHINA OVER THE LAST 2000 YEARS   总被引:4,自引:0,他引:4  
1 INTRODUCTIONIn the last years, evidence for climate changes showed that the timing of the two great climatic events of “Medieval Warm Period” (MWP) and “Little Ice Age” (LIA) differed geographically (HUGHES et al., 1994, JONES and BRADLEY, 1992). In other words, the cold or warm periods in one region were often not coincident with those in other regions. The Northern Hemisphere warmth degree in the Middle Ages was lower than or at most comparable to that in the mid-20…  相似文献   

13.
针对深处青藏高原腹地中低纬度高海拔(4 600~5 300m)永冻土地带的青海乌丽地区,开展了该地区天然气水合物形成的气源条件研究。冻土区地表沿断层发育若干冷泉,野外采集冷泉新鲜水500mL密封送实验室进行气相色谱分析。首先对水中溶解的烃在真空和60℃恒温条件下脱出气体,将脱出气体经ρ(NaOH)=300g/L的碱液吸收CO2,余下气体经碱液驱赶至量气管上端,计量脱出气体的体积,并转移至另处;然后根据溶解烃含量注入适当体积的脱出气体进行色谱标定、单点外标定量。结果在冷泉中检测出CH4体积分数一般在223.60~1 097.30 μL/L之间,最高达1 113.21 μL/L。野外工作查明烃源岩主要为上二叠统那益雄组含煤碎屑岩建造,次为上三叠统巴贡组碎屑岩。前者中赋存的煤层及炭质泥岩为天然气水合物气源供给的重要母质。此研究成果揭示该地区具备形成天然气水合物藏的良好气源条件及成藏潜力。   相似文献   

14.
Introduction Agriculture, which is the dominant sector in the mountains, is generally stagnant. Degradation of the natural resource base has contributed to an increase in frequency and intensity of landslides, gully formation, soil erosion, declining soil fertility, reduced per capita availability and fragmentation of land, and reduced flow of water for irrigation. This has led to steady decline in crop yields (5~30 %) or stagnation that caused food shortages at varying degrees among mountain …  相似文献   

15.
Tetraploid induction was carried out by inhibiting mitosis I in fertilized eggs ofChlamys farreri. Mitosis I was blocked with cold shock (5–7°C), Cytochalasin B (0.75 mg/L) and 6-dimethylaminopurine (6-DMAP) (60–75 mg/L) when 60% fertilized eggs released polar body II at 20°C. At 4-cells embryo stage, the ploidy was determined by counting chromosome number. In control groups, most embryos were diploids (72.22%) and aneuploids (24.78%). In Cytochalasin B, cold shock and 6-DMAP treated groups, tetraploids were respectively 10.51%, 4.08%, and 13.34%; aneuploids were 43.10%, 35.93% and 29.16%, and triploids were 7.84%, 8.52% and 18.33%. At D-larva stage, ploidy was determined by flow cytometry (FCM). The ploidy analysis of day 2 larvae showed diploids in control group and also in three treated groups. Juvenile scallops (0.2–0.3cm) which were harvested in two control groups and two CB treated groups were all diploids through checking ploidy individually by FCM. Contribution No. 3648 from the Institute of Oceanology, Chinese Academy of Sciences. Contribution No. 238 from the Experimental Marine Biology Laboratory, Chinese Academy of Sciences. Project funded by grant (No. 819-01-07) from the Chinese Science and Technology Ministry and also by “Hundred Talents Plan” grant from the Chinese Academy of Sciences.  相似文献   

16.
Bay scallops were introduced from the east coast of the U.S. into China to shorten the economic turn-over from 2 to 1 year. Parent scallops were carried to Qingdao on Dec. 20, 1982 and stocked in indoor tanks at controlled temperature and fed with a mixture ofPhaeodictylum tricornutum, Pyramimonas sp. andChlorella sp. They spawned on Jan. 26 of the next year. The larvae were reared at a temperature of 18–21°C and fed withIsochrysis galbana, Pyramimonas sp. andChorella sp. In 4 weeks’ growing, the spats averaged 827 μm. They attained a height of 6.9 mm on May 9. In the middle of May, the seed scallops were transferred to Luoyuan Bay in Fujian Province, and Jiaozhou Bay, as well as the area off Taiping Jiao Cape, Qingdao, Shandong Province for experimental culture in plastic netcages suspended on a single line raft. Bay scallops cultured in Luoyuan Bay grew to an averaged shell height of 10.4 mm. In Jiaozhou Bay and the Taiping Jiao Cape culture area, they grew to 50 mm in average shell height (marketable size) and 26 g in average weight by late September; and attained 59 mm in average shell height (R. 39–75 mm) and 46 g in average weight in late December. The ovary and testis could be distinguished by color in August. In early September, eggs and sperms were collected for our laboratory where the second generation of seed scallops was successfully reared to suitable size for growing outdoor and breeding. This species can be harvested within a year after fertilization of the eggs, so we consider it suitable for culture in the Yellow Sea and East China Sea. This is the first reported successful introduction of Atlantic mollusks to the China Seas. This paper was published in Chinese inOceanologia et Limnologia Sinica 17 (5): 367–374, 1986.  相似文献   

17.
We studied the effect of pH(pH 5, 6, 7 and 8) on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay(BHB), Artemia franciscana from San Francisco Bay, and A. franciscana artifi cially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were signifi cantly reduced when exposed to a culture medium at pH 5 for 18 d( P 0.05). The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order: juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6–8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidifi cation has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franciscana should be feasible at pH 7–8.  相似文献   

18.
主要介绍ABB机器人自动磨抛系统控制原理,及其在水暖卫浴产品中的应用分析,同时介绍其硬件配置和软件设计。采用ABB第五代机器人控制器IRC5,给出基于DeviceNet总线的硬件设计过程。实现ABB机器人及自身快速、柔性配合,极大的提高生产效率。  相似文献   

19.
INTRODUCTIONRedtidecanadverselyaffectcoastalfisheriesbycausingthedeathofculturedfishandshrimporproducingtoxinsthatcanbeaccumulatedthroughfoodchains (Anderson ,1 989) .Phytoplanktonisoftenthemaincomponentofmanyredtides.AlongthecoastofJiaozhouBay ,P .R .China,theredtideismainlyformedbyadinoflagellate ,Scrippdiellatrochoidea ,duringsummer (JulytoSep tember)andthecelldensitycanreach 9.98× 1 0 7cells ml (Zou ,unpublisheddata) .Manyresearcherssuggestedthatredtideofphytoplanktonmightresultf…  相似文献   

20.
Geochemical characteristics of rare-earth elements (REE) and sedimentary features were studied in the borehole 96-7-1 from Elson Lagoon in Barrow, Arctic Alaska. The results show that total contents of REE (∑ REE) are lower, suggesting that physical weathering is dominate, therefore, concentrations of rare-earth elements are lower in the paleosediment environment. The chondrite-normalized distribution patterns of RE,Es are characterized by light REE (LREE) enrichment and Eu-depletion with the terrestrial sedimentary rock as the parent materials. In comparison with the borecore AB-67 in Elson Lagoon, the main conclusions for climatic and environmental changes are similar: before 1740 A. D. , it was cold and dry with terrestrial properties,but the comparatively warming around 1400 A.D. and 1550 A. D. ; after 1740 A. D. ,it became warming, or markedly after 1821 A.D. ; but it was cold around 1890 A. D.From 1904 A. D. , it got warm again, but it was relatively cold around 1971 A. D..  相似文献   

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