Chilling Stress Accelerates Degradation of Seed Storage Protein and Photosynthetic Protein during Cotton Seed Germination

Low temperature is one of the major abiotic stresses limiting the productivity and geographical distribution of many important crops. To gain a better understanding of chilling stress responses in cotton ( Gossypium hirsutum L . ), we carried out a comparative proteomic analysis. Cotyledon proteins of 1-week-old cotton seedlings treated with or without chilling treatment at 4 °C were extracted, separated by a two-dimensional gel electrophoresis and compared. Among 1500 protein spots reproducibly detected on each gel, 25 protein spots were down-regulated and 29 were up-regulated. Seven cotton proteins were identified by mass spectrometry analysis as beta-globulin A precursor fragments. One was identified as a Rubisco large subunit fragment, providing evidence of both seed storage protein and photosynthetic protein destruction by chilling stress. The related physiological and biochemical analysis showed that there was a significant increase in endopeptidase activity and activated oxygen generation rate, and an obvious decrease in carboxylation efficiency and maximum net photosynthetic rate of cotton seedlings under chilling stress. Based on the above results, the degradation mechanisms of beta-globulin and Rubisco under chilling stress were discussed. In conclusion, our study provides new insights into chilling-stress responses in cotton and demonstrates the advantages of proteomic analysis.     

木本植物芽内休眠机制的研究进展

木本植物芽的内休眠是植物经过长期演化而获得的一种对环境及季节性变化的生物学适应性,其机制较为复杂.了解内休眠的机制,调控芽的休眠与萌发,具有重要的理论意义和应用价值.在探讨内休眠概念的基础上,重点阐述内休眠诱导及解除的影响因素、内休眠过程中的代谢变化、顶端分生组织内细胞间通讯及细胞周期调控、内休眠相关基因等方面的研究进展,提出今后内休眠调控机制的研究重点.     

半夏小块茎悬浮培养及其生物碱类化合物的测定

【目的】筛选半夏小块茎悬浮培养过程中诱导和继代的最佳培养基,并对小块茎中生物碱类化合物的含量进行测定,为半夏生物碱的生产及其次生代谢物的调控提供参考。【方法】在添加不同激素的MS培养基上诱导、增殖半夏小块茎,并建立未分化小块茎的液体悬浮培养体系,采用酸性染料比色法测定小块茎的总生物碱含量,高效液相色谱法测定小块茎中鸟苷、肌苷和葫芦巴碱的含量。【结果】以块茎、叶片叶柄为外植体诱导半夏小块茎的最佳培养基分别为MS+0.5mg/LNAA+1.0mg/L6-BA和MS+0.2mg/LNAA+1.0mg/L6-BA;小块茎最适继代培养基为固体1/2MS+0.6mg/LABA;小块茎的液体悬浮培养基为液体1/2MS+0.6mg/LABA。与栽培块茎相比,以块茎及叶片叶柄为外植体诱导的半夏小块茎总生物碱含量分别提高了4.46倍和2.07倍。以块茎为外植体诱导的半夏小块茎中,鸟苷和葫芦巴碱的含量分别是栽培块茎的10.6和2.5倍;而肌苷含量降低,约是栽培块茎的1/3。以叶片叶柄为外植体诱导的半夏小块茎中,鸟苷和葫芦巴碱的含量分别比栽培块茎增加了1.1和1.9倍,肌苷含量约为栽培块茎的1/4。【结论】半夏组培小块茎可作为一种模式材料,用于半夏生物碱的生产以及鸟苷、肌苷和葫芦巴碱的代谢调控。     

中国大豆品种熟期组划分的研究

根据北美13个熟期组大豆代表品种48份及我国各地地方品种256份在南京春播自然条件结合18小时长光照条件的试验,部分品种在石家庄、哈尔滨的春播试验,获得以下主要结果：(1)将我国大豆品种归属为相应的000～Ⅸ共12个熟期组,未发现熟期组Ⅹ品种;(2)按同一熟期组品种生育前期变异的地理分布,0～Ⅲ熟期组内各划分为秦岭淮河     

陕西省粮食生产波动的时序分析

以 1 953～ 1 997年粮食生产统计数据为依据 ,在分离陕西省粮食生产波动的基础上 ,总结了粮食生产波动规律和时序分布特征 ,分析了粮食生产波动的成因机制 ,并对迈向 2 1世纪陕西省粮食生产形势作了相应的预期。     

多种小麦蛋白质酸性聚丙烯酰胺凝胶电泳方法研究

研究了离子强度、缓冲液 p H、慢离子浓度、凝胶浓度等因素对小麦蛋白质 APAGE分离效果的影响 ,采用 L1 6 ( 41× 2 1 2 )正交试验进行了条件优化 ,所建立的甲酸盐 APAGE方法 ,具有分辩率高、重复性好的特点 ,可通过改变凝胶浓度实现不同蛋白的分离研究。因而此法在小麦蛋白分离、遗传研究、品种鉴定等方面具有广阔的应用前景     

Genetic Diversity and Evolutionary Tendency Detected by Isozyme, RFLP and RAPD Markers in the Wild and Cultivated Soybean in China

A large numbers of samples of wild soybean accessions and cultivated soybean landraces from various areas in China were analyzed by isozyrme, cytoplasmic DNA RFLP and nuclear DNA RAPD markers in order to reveal their genetic diversity. Greater comprehensive genetic diversity was detected in wild soybean than in cultivated soybean. The genetic plentifulness and the genetic dispersion of wild soybean were 180 (95. 2％) and 0. 2891 while those of cultivated soybean were 154(81.5％) and 0. 2091,respectively. On the most loci, especially on isozyme loci Idh1, Aph, Idh2,and Dia, cytoplasmic DNA RFLP loci cp Ⅰ , cp Ⅲ, mt Ⅳ a and mt Ⅳ b, and nuclear RAPD loci OPAP4-8, OPAP5-1, OPAP9-8 and OPAP20-8, the wild soybeans djffered remarkably from the cultivated ones in allele frequency. These markers could be used in further study on the evolution and origin of the cultivated soybean.     

人与自然的和谐——农业院校必须加大生态学与环境保护教育

人与自然和谐相处、和谐发展的关键是发展,是在发展中寻求和谐、建立和谐、完善和谐、升华和谐。必须以更大的决心和力度推进生态环境建设,建立人与自然新的更高水平的和谐。农业院校要大力促进人与自然和谐相处、和谐发展,在课程设置上应该加大对生态学和环境保护的教育。     

田间条件下大豆气孔特性的初步研究

对12个中国和日本大豆品种在田间两种种植密度下结荚期气孔特性研究表明:气孔密度(SD)、气孔长度(SL)和单位叶面积的气孔总长度(SD×SL)在主茎叶位间、叶片正背面间有显著差异。种植密度间SD和SD×SL差异显著,但SL无差异。品种间SL和SD×SL差异显著,但SD的品种间差异受密度影响。SD与SL显著负相关,与SD×SL显著正相关。光合速率在叶位间和品种×叶位间与SD和SD×SL显著正相关,与SL显著负相关。     

四川“榨菜”花叶病毒鉴定及不同季节和地点发生情况调查

 四川"榨菜"以其鲜、香、嫩、脆特色享誉全国,但原料茎瘤芥花叶病为害严重,流行年减产四成以上。王廷泉(1962年)对其病原、流行规律及防治曾作研究,但大面积的病原种类和分布尚无报导。