不同基因型高梁的理化特性与抗蚜性的相关性研究

通过对抗蚜的河农16和感蚜品系Tx623B、Tx622B、Tx3197B、千三、晋五及杂交种的物理特性、组织结构、生理生化特性的对比分析,研究了不同基因型高粱理化特性与抗蚜性的相关性。结果表明,高粱抗蚜品系叶片表面较感蚜品系的细胞排列整齐、致密、表皮细胞直径较感蚜品系小、叶片薄、叶片表面光滑、叶片颜色浅。感虫后各品系过氧化物酶（POD）、多酚氧化酶（PPO）活性均有升高,与蚜虫的诱导存在相关性,但不同品系感蚜前后均不存在趋势性变化;苯丙氨酸解氨酶（PAL）酶活性感虫前在抗虫的河农16及杂交种中具有高水平表达,并与其他感蚜品系存在显著差异;蚜虫侵害诱导后PAL酶活性均有上升,但抗蚜品系中表现稳定,酶活性变化幅度与叶片损伤程度存在相关性,PAL酶活性与高粱的抗蚜性存在明显的相关性。感虫前后氨基酸含量及其变化与高粱品系抗蚜性间无相关性;在感蚜虫前,抗蚜品系及其杂交种可溶性糖含量显著高于感蚜品系,接虫后感蚜品系可溶性糖含量升高显著。     

棉花抗蚜性与苯丙氨酸解氨酶活性的关系

为探讨苯丙氨酸解氨酶活性与棉花抗蚜性的关系,在室内人工接蚜危害和田间自然蚜群2种条件下,测定不同抗蚜性棉花品种受棉蚜Aphis gossypii Glover危害后叶片的PAL活性。结果表明:未受棉蚜危害时,抗、感品种PAL活性无明显差异;棉蚜危害胁迫棉花PAL活性升高,抗蚜品种受到棉蚜危害诱导所产生的PAL活性远比感蚜品种高。田间有蚜株率与棉花叶片苯丙氨酸解氨酶活性的呈显著的负相关关系。研究说明PAL酶活性对棉花的抗蚜性有一定的影响。     

对高粱抗蚜植株形态及组织结构的观察

以BTAM428（高抗）和ICS-12B（高感）及二者杂交的F2代为试材,对其形态及组织结构进行研究。结果表明：抗感品种形态及组织结构上均有差异。在抗蚜高粱品系的气孔数目多于感蚜品系;其下表皮的表皮蜡质比感蚜的致密;维管束的直径则小于感性的。     

茉莉酸甲酯对菊花抗蚜性的影响

本研究以杭白菊为试验材料,分析茉莉酸甲酯对菊花抗蚜性的影响。供试幼苗叶面喷施不同浓度(0.01、0.05、0.1、0.5、1 mmol·L^-1)茉莉酸甲酯后接种菊姬长管蚜,测定外源茉莉酸甲酯对蚜虫胁迫下菊花叶片的保护酶、防御酶活性、渗透性物质、次生代谢物和茉莉酸途径关键酶基因表达的影响,探究菊花抗蚜性与茉莉酸信号途径的关系。结果表明: 0.01、0.05、0.1、0.5、1 mmol·L^-1浓度的茉莉酸甲酯均显著提高了杭白菊叶片的保护酶、防御酶活性及次生代谢物含量,降低了丙二醛和可溶性糖含量,外源茉莉酸甲酯处理诱导杭白菊CmAOS和CmCOI1的表达,并使内源茉莉酸含量显著增加,杭白菊的抗蚜性增强。     

高粱抗高粱蚜的生化基础

高粱中的可溶性总氮、可溶性总糖和绝大部分游离氨基酸,特别是必需氨基酸,在感性品种中的含量显著地比抗性品种中的含量高.感性品种叶液微偏酸,抗性品种近中性.多元回归分析表明,高梁对高粱蚜Melanaphis sacchari(Zehntner)的抗性与可溶性总氮、可溶性总糖和游离氨基酸的含量呈反相关.     

夏季苹果新梢生理指标与抗苹果绵蚜的关系

研究苹果生理指标与其对苹果绵蚜(Eriosoma lanigerum Hausmann)抗性的关系,为筛选培育抗性品种,实现持续有效治理苹果绵蚜提供依据.田间调查不同苹果品种对苹果绵蚜的抗性,测定比较各品种正常枝条生理指标,以及被苹果绵蚜危害后生理指标的变化.结果表明,正常枝条中可溶性糖(r=0.99)、蛋白质(r=0.86)含量与感蚜率呈正相关;氨基酸含量与感蚜率呈负相关(r=-0.96);酚类物质和4种酶活性与苹果感蚜率均不存在明显相关性.被害后昭锦108可溶性糖含量有所下降,红富士、金冠分别上升1.4％、7.0％;蛋白质、氨基酸、酚类物质含量均有所下降,其中红富士总酚含量明显下降,达23.5％,总酚下降率与感蚜率呈正相关(r=0.94);超氧化物歧化酶(Superoxide Dismutase,SOD)、过氧化氢酶(Catalase,CAT)活性均上升,其中CAT变化率与感蚜率存在相关性(r=-0.92),昭锦108 CAT活性明显上升,达91.2％;多酚氧化酶(Polyphenol Oxidase,PPO)、过氧化物酶(Peroxidase,POD)活性增减不一;金冠4种酶活性均上升.研究表明,对苹果绵蚜抗性较强的品种:可溶性糖、蛋白质含量较低,游离氨基酸含量较高;受害后可溶性糖含量下降,总酚含量下降率较低,游离氨基酸含量下降率较高.酶活性对抗蚜性的影响不明显.     

望谟紫芽茶树优良品系‘W016’与黄金芽抗茶蚜性能比较

茶蚜Toxoptera aurantii Boyer是茶树上的重要害虫之一,深入研究抗蚜特异资源的抗性机理对培育茶树抗蚜品种具有重要意义。课题组前期收集的望谟紫芽茶树优良品系‘W016’对茶蚜抗性强,为初步探明该种质的抗蚜特性,利用刺吸电位技术测定了茶蚜在‘W016’和黄金芽(感虫品种)上的取食行为,并探明影响茶蚜刺探取食叶片的主要物理性状及生化成分因子。结果表明,茶蚜在两种供试种质上均产生9种EPG波形,依次为非刺探波(np波)、路径波(A波、B波、C波、pd波)、机械阻力波(F波)、木质部吸食波(G波)、韧皮部唾液分泌波(El波)和韧皮部汁液吸食波(E2波)。刺探取食过程中,茶蚜在‘W016’上的非刺探时间(np波)和C波总持续时间均显著长于黄金芽。二者口针遇到阻力的次数(F波)和总持续时间无差异,但韧皮部吸食汁液(E2波)时间‘W016’显著短于黄金芽。茸毛密度、下表皮厚度和栅栏组织厚度是‘W016’抗茶蚜取食胁迫的主要物理屏障因子,而咖啡碱和可溶性糖含量为主要生化因子。表明‘W016’对茶蚜的取食抗性与其叶片理化性质密切相关。     

蚜虫(Aphis medicaginis Koch)危害胁迫对不同苜蓿品种体内丙二醛含量及防御性酶活性的影响

研究了蚜虫危害胁迫后不同抗蚜性苜蓿品种叶片内丙二醛含量及防御性酶活性的动态变化。结果表明：在蚜虫刺吸诱导的过程中,高感品种的MDA含量始终高于高抗品种,并且高感和高抗品种均保持上升的趋势;高感品种的SOD、POD和PAL活性始终低于高抗品种,其中高感和高抗品种的SOD和POD活性均表现先上升后下降的趋势,而PAL活性上升到高峰后均趋于稳定;CAT活性在高感和高抗品种间表现为交替的上升下降;高抗品种的PPO活性前期低于高感品种,而后期高于高感品种。由此可见,在蚜虫危害胁迫下,高感和高抗品种间MDA、SOD、POD、PAL和PPO活性的变化与苜蓿的抗蚜性密切相关,均可作为苜蓿抗蚜性鉴定的生理指标,而CAT活性变化与苜蓿抗蚜性的联系有待进一步研究。     

辣椒感染疫病后生化指标的响应研究

采用生理生化分析方法研究了辣椒感染疫病后叶片中几个生化指标的变化。结果表明,染病前后感病品种叶片中可溶性总糖含量持续高于抗病品种;抗病类型品种和感病类型品种的可溶性蛋白含量变化规律均表现为先升高后下降,但接种前其叶片中可溶性蛋白含量两者间无明显差异;抗病类型和感病类型辣椒接种后保护酶活性均升高,而且感病类型的POD和ASP酶活性在接种后120h显著高于抗病类型;高抗类型叶片中PPO活性增加幅度显著大于感病类型,但抗病类型品种PPO活性上升趋势比较平缓。接种后,感病品种PAL活性上升幅度小于高抗品种,接种后96h PAL活性开始逐渐下降。可溶性总糖含量和苯丙氨酸解氨酶可以作为辣椒苗期抗疫病鉴定的生化指标。     

小麦抗禾缢管蚜的生化研究

通过福林法、葸酮法、滴定法等分别测定了不同抗蚜性小麦品种植株中酚、糖含量及酸度。结果表明：小麦对禾缢管蚜尺Rhopalosiphum padi(Linnaeus)的抗性与小麦体内酚含量有关,抗性强的小麦其体内含酚量相对高,反之低。同时小麦抗性的强弱与体内糖含量,酸度亦有相关性。另外还测走了在不同抗性小麦品种上生长的蚜虫体内淀粉酶及羧酸酯酶的活性,结果表明在抗性强的小麦品种上生长的蚜虫体内淀粉酶,羧酸酯酶活性强,反之弱。     

Microbial Changes in Sweet Sorghum (Sorghum bicolor) Juices

Juice freshly expressed from Sorghum bicolor for making sweet sorghum syrup contained 10⁸ microorganisms per ml. The dominant bacterium was Leuconostoc mesenteroides, followed by gram-negative rods. Lactobacilli, yeasts, and nonfecal coliform bacteria each comprised about 1% of the microbial population. Spoilage of juice, manifested by a sour odor, discoloration, and foaming, occurred between 5 and 12 h at ambient temperatures. Spoilage was correlated with a drop in pH from 4.9 to 4.5 L. mesenteroides was the dominant spoiling agent at 20°C, and Lactobacillus plantarum was the dominant spoiling agent at 32°C, as determined by pure culture studies. Juice may be stored for 14 days at 4°C if promptly refrigerated.     

Sorghum as brewing material

Conclusion The white-skinned, low polyphenol cultivars of sorghum are the most likely to be used as brewing raw materials for adjunct and/or malt production. Efficient use of a food grain such as sorghum in brewing, demands that ample supplies are available and that by-products of adjunct or malt production are processed and marketed efficiently. Present research on the brewing potential of sorghum will undoubtedly benefit the agricultural development of the crop.Many countries are known for the famous drinks and beverages they produce. The cost of sorghum beer production must therefore be measured against drinkability of the product. A sub-standard product will not develop and will reflect badly on its producer. Although complete conversion of sorghum starch to fermentable sugars is avoided in brewing, efficient conversion of starch into glucose will require the addition of suitable commercial heat-stable amyloglucosidase enzymes. Future work on sorghum must be conducted scientifically and technologically with regard to its suitability as adjunct and/or as malt.     

Action of Sorghum Proteinase on the Protein Bodies of Sorghum Starchy Endosperm

Protein bodies isolated from the starchy endosperm of ungerminatedsorghum exhibited some autolytic activity but seemed incapableof significant self-hydrolysis. Enzyme assay, transmission electronmicroscopy, sodium dodecyl sulphate—polyacrylamide gelelectrophoresis and amino acid analysis revealed that a proteinaseextract from germinated sorghum could degrade the protein bodiesin a manner resembling that which takes place in vivo. The proteinbodies were degraded mainly from the periphery. Glutelin (matrixprotein) was first hydrolysed, followed by the prolamin proteinbody protein. Proteinase extracts from both the germ and endospermof germinated sorghum were capable of degrading the proteinbodies. This finding is consistent with the concept that theproteinase is synthesized in the germ and then secreted intothe starchy endosperm during germination. Key words: Sorghum bicolor, protein body degradation, proteinase.     

高粱基因组学研究的新进展

高粱是全球第五大禾谷类作物,在干旱、半干旱地区农业生产中占有极其重要的位置.高粱基因组相对较小(750Mbp),遗传多样性丰富,被认为是禾谷类作物比较基因组学研究的模式基因组之一.近年来,综合运用AFLP等分子标记、BAC文库、EST及cDNA作图和FISH技术,加速了高粱高分辨率基因组图谱的构建.高粱基因测序、基因功能鉴定和克隆,以及遗传转化,亦取得了长足的进展.高粱特有的多种适应逆境胁迫等优异基因资源的发掘及其在作物改良中的应用前景广阔.     

Allozyme variation among the spontaneous species of Sorghum section Sorghum (Poaceae)

Summary A survey of allozyme variation among the spontaneous taxa of Sorghum section Sorghum was undertaken. Eight plants each of 90 accessions representing the diploid S. bicolor (ssp. arundinaceum and drummondii) and the tetraploids S. almum and S. halepense were analyzed for 17 enzyme systems encoded by 30 loci. Low levels of variation were found within and among accessions, although there was more variation than is typical of inbreeding species. We found an average of 3.2 alleles per locus in ssp. arundinaceum, with a mean expected heterozygosity for the accessions of 0.034 and total panmictic heterozygosity of 0.154. An analysis of the apportionment of genetic variation among accessions of ssp. arundinaceum indicated that 26% of the variation occurs within accessions and 74% among accessions. Cultivated sorghum contains far less allozymic variation than ssp. arundinaceum, its presumed progenitor. This is consistent with the prediction that cultivated sorghum experienced a loss of genetic variation during domestication. For the most part, cultivated sorghum contains a subset of the allozymes found in ssp. arundinaceum. Principal component analysis revealed continuous variation among the accessions and geographic regions, with accessions failing to segregate into discrete clusters. However, accessions of race virgatum of ssp. arundinaceum occupied one end of the continuum and were, in that sense, distinguished from the other accessions. Similarly, most accessions of S. halepense and S. almum occupied the central portion of the continuum. The allozymic data presented here are consistent with the hypothesized origin of S. halepense via autopolyploidy or segmental allopolyploidy.     

根癌农杆菌介导的高粱遗传转化体系的研究

采用根癌农杆菌介导法将杀虫晶体蛋白基因cryIA(b)转入高粱胚性愈伤组织中,建立农杆菌转化高粱的遗传转化体系,获得70棵再生植株。经GUS及PCR检测,结果表明,cryIA(b)基因确实转移到高粱恢复系0-30中,报告基因GUS在再生植株中也得到表达。转化植株的抗病性鉴定正在进行中。     

高丹草EST-SSR标记的开发及其遗传多样性

对NCBI数据库中210 878条高粱EST序列进行处理, 得到57 498条无冗余EST序列, 经SSR搜索, 发现3 338个SSR分布于3 116条EST序列中, 分布频率为1/11.28 kb, 包括215种基元重复类型。其中三核苷酸重复最高, 占68.33%, 二核苷酸重复占17.97%。3 338条SSR序列中有1 694条序列能够设计出引物, 所占比例为50.75%。选取14对引物进行合成, 对50份高丹草、7份高粱和3份苏丹草材料进行了EST-SSR扩增, 共检测到72个等位变异, 平均每对引物检测出5.14个基因位点。每对引物多态性指数范围为0.54~0.93, 遗传距离的变化范围0.1646~0.6398。结果显示：供试材料具有较丰富的遗传多样性, 根据EST-SSR数据的聚类分析, 将供试材料按亲缘关系远近分为5大类, 来源相同的品种大致聚在一类, 呈现出一定的地域性分布规律。同时发现4个特异分子标记, 其中引物D1763只对314A和白壳苏丹草杂交后代GB-4-2高丹草审定品种产生特异性, 此标记已作为该材料的特异性标记用于种质资源的鉴定中, 同时表明, EST-SSR标记是高丹草遗传多样性及特异性研究的一种有效方法。     

Genetic transformation of Sorghum bicolor

Great millet (Sorghum bicolor (L.) Moench) is cultivated across the world for food and fodder. It is typically grown in semiarid regions that are not suitable for cultivation of other major cereals. Sexual incompatibility and shortage of available genes in germplasm to combat biotic and abiotic stresses resulted in marginalized yields of this crop. Genetic modification of sorghum with agronomically useful genes can address this problem. Here, we tried to review and summarize the key aspects of sorghum transformation work being carried out so far by various research groups across the world. The approaches used and the obstacles in generating transgenic sorghum are also pointed out and discussed.     

Sorghum Insect Problems and Management

Sorghum (Sorghum bicolor) has high levels of starch,sugar,and fiber and is one of the most important energy crops in the world.Insect damage is one of the challenges that impacts sorghum biomass production.There are at least 150 insect species that can infest sorghum varieties worldwide.These insects can complete several generations within a growing season,they target various parts of sorghum plants at developmental stages,and they cause significant biomass losses.Genetic research has revealed the existence...