水稻种衣剂对秧苗生理生化及叶绿素荧光参数的影响

以‘深两优5814’水稻种子为试验材料,用2.5%吡·咪、3%恶·咪、锐胜和适乐时分别包衣种子,测定水稻幼苗抗氧化酶活性、MDA含量、GSH含量、叶绿素含量和叶绿素荧光参数,探讨种衣剂对幼苗的胁迫机理,为种衣剂的安全高效应用提供理论依据。结果表明:(1)种衣剂能提高水稻幼苗的抗氧化酶活性,播种后14d,2.5%吡·咪和锐胜处理组叶片的SOD活性上升,3%恶·咪处理组叶片的POD活性上升;播种后22d,2.5%吡·咪和3%恶·咪处理组叶片的CAT活性上升;播种后26d,锐胜和适乐时处理组叶片的CAT活性上升;2.5%吡·咪和3%恶·咪显著提高了播种后22d叶片的MDA含量。4种种衣剂均能提升幼苗叶片GSH含量,并以3%恶·咪的提升效果最为明显。(2)4种种衣剂均能降低叶绿素含量,但随培养时间的延长叶片内叶绿素含量逐渐恢复到正常水平。(3)4种种衣剂对水稻叶片最大光化学效率φPo无显著影响,吸光性能指数PIABS值也未呈下降趋势,比活性参数ABS/CSM值随培养时间的延长出现下降趋势,其中以3%恶·咪处理组下降最为明显;同时,3%恶·咪处理组叶片的热耗散DIo/CSM值也显著高于对照。研究认为,各种衣剂对水稻幼苗生长造成了一定的胁迫,但水稻自身防御体系能有效缓解农药胁迫作用,种衣剂的使用处于安全水平,但3%恶·咪的胁迫较严重,使用效果较差。     

壳聚糖及其衍生物在医药上的应用

本文着重对壳聚糖及其衍生物的抗菌特性,降低血清胆甾醇和抑制高血压的特性及其作为肝素材料在医药上的应用进行综述,并展望了其在医药上的发展前景。     

甲壳质,壳聚糖在农业上的应用

本文综述了甲壳质、壳聚糖作为降解性地膜、植物生长调节剂、肥料和土壤改良剂、农药、食物保鲜剂及饲料、饵料添加剂等在农业方面的应用。     

水稻育秧抗寒剂研究成功

我被确定从事“植物抗寒性的细胞学研究”从一个故事和一个想法谈起。这个故事是,正当我高考前夕,我看了一部有关米邱林通过改良果树品种与寒冷作斗争的电影故事片,就是这部故事影片导致我在我的高考志愿表中填写了北京大学生物系,并且如愿以偿。有意思的是,在我1957年开始步入研究生涯的最初工作——小麦丰产试验工作中,即感受到北方冬小麦越冬过程中,也因冻害遭到损失,影响小麦稳产高产。低温寒害还严重危害着许多其他粮食作物、果树、蔬菜及经济作物的生产。研究克服它的危害是科学研究的重要任务之一。1959年,当我的老师吴素萱教授为安排我今后的     

水稻育秧抗寒剂的研制及应用

低温寒害是农业生产中一种严重的自然灾害,涉及的面很广,包括粮食作物、蔬菜、果树、园林及其他许多经济作物。水稻是我国的主要粮食作物,种植面积居各种作物之首位,达5亿多亩,其早春育秧中的低温烂秧问题,从北到南几乎年年都有发生,不仅造成稻种的巨大损失,而且延误农时,导致严重减产。鉴于此种情况,我们在多年研究植物抗寒机理的基础上,提出了“水稻育秧抗寒剂”的研制目标。经过长达6年的从实验室、盆栽到大田的系统试验,现在已经取得了较为理想的结果,有待广泛推广。     

壳聚糖的性质和用途及其在农业上的应用前景

壳聚精（chitosan）为甲壳素（chitin）的降解产物。甲壳素是类似纤维素的生物聚合物,畜量仅次于纤维素,为世界上第二大类有机地合物,广泛存在于动物和真菌中,其中海生的无脊椎动物和昆虫的外壳甲壳素量较多。甲壳累资源丰富,制备简单,在美国和日本生产已经工业化［‘’j。我国沿海地区辽阔,每年捕捞虾蟹数量极多,除虾蟹的可食部分外,还留下大量含有甲壳素的废物。但到目前为止,甲壳素和壳聚糖的生产尚未形成规模。国内生产的壳聚糖价格为6．5～85万一、吨,外贸价为国内价的10倍左右。将虾头H及含甲壳素的废料转化为壳聚糖,不…     

壳聚糖在香蕉果实贮藏保鲜上的应用效果

以巴西香蕉果实为材料,研究了不同浓度（0、0．5％、1．0％、2．0％）的壳聚糖溶液对香蕉果实贮藏保鲜的影响。结果表明：壳聚糖处理可明显延缓香蕉果实的软化进程和病情指数的升高;同时维持了果实较低的细胞膜透性、多酚氧化酶（PPO）活性和较高的苯丙氨酸解氨酶（PAL）、β-1,3-葡聚糖酶（GUN）的活性。在四种处理中,以2％壳聚糖处理效果最好。表明壳聚糖对香蕉果实的贮藏保鲜效应可能与其调控病害相关酶的活性有关。     

碱性磷酸酶在壳聚糖上的固定化作用

本文报道以蟹、虾废壳为原料提取壳聚糖,用戊二醛作交联剂,将碱性磷酸酶固定于壳聚糖上。同时探讨了一定量湿壳聚糖载体与交联剂浓度,给酶量及产率等关系的最适固定化酶条件,并对固定化酶的热稳定性、操作稳定性、米氏常数、最适pH、最适温度等理化性质进行了探讨。     

天然多糖——几丁/壳聚糖在烟草工业上的应用——新型高效吸附剂的研究初探

二 将壳聚糖微粒化,用于香烟的过滤咀中,利用壳聚糖的吸附特性,测定其对烟气中的总粒相物及植物碱的吸附能力,比较其与醋酸纤维吸附能力的大小,得到令人欣喜。的结果。     

壳聚糖在组织工程中应用的研究进展

壳聚糖是由2-氨基-2-脱氧-β-D-葡萄糖通过β-1,4糖苷键聚合的一种天然聚阳离子生物多糖,结构类似硫酸软骨素、透明质酸等物质,体内移植或注射无炎症和变态反应,在动物体内可被降解为氨基葡萄糖,参与代谢,表现出良好的生物相容性和生物可降解性,是细胞培养的良好的脚手架,因而在组织工程中显示出较为广泛的应用前景。综述了壳聚糖在皮肤修复、神经修复、骨及软骨修复、肝脏修复等方面的研究进展 。     

高吸水性种衣剂对水稻旱育秧苗生长的影响

高吸水性树脂具有较强吸水保湿功能,使用高吸水性水稻种衣剂培育旱育秧苗,可以有效控制苗床水分和湿度,同时能缓释农药和肥料,增强秧苗抗逆性。试验表明,高吸水性种衣剂处理对水稻发芽率和发芽势无不良影响,且壮根、壮苗效果显著;能减少病害发生,保持旱育秧苗发根优势和分蘖优势,达到省工省时的目的。     

水稻根表铁膜吸附镉及植株吸收镉的动态

采用营养液培养法研究了Cd处理时间对有铁膜和无铁膜水稻根表吸附Cd及植株吸收Cd动态变化的影响.水稻根表铁膜由50 mg·L^-1 Fe^2＋（Fe₅₀）诱导形成.供试植株在含10 μmol·L^-1Cd的营养液中生长不同时间后收获.结果表明, 随Cd处理时间的延长,无铁膜和有铁膜处理水稻根表DCB-Cd含量均为先增加后减少,Cd处理2 h达到最高,之后逐渐下降并趋于稳定. 根系和地上部Cd含量均持续上升,Cd处理8 h前增加缓慢,8 h后增加幅度加大.有铁膜水稻根系和地上部Cd含量增加幅度均低于无铁膜水稻.有铁膜处理DCB-Cd含量、根系和地上部Cd含量均低于无铁膜处理.表明铁膜不影响水稻各部分Cd含量随时间的变化趋势;不同Fe处理之间根系和地上部Cd含量的差异可能与根系含Fe量有关.     

Calcium peroxide as a seed coating material for padi rice

Summary Measurement of oxygen uptake by germinating rice seed (Oryza sativa L) suggests that oxygen requirement is independent of temperature of incubation. However, the rate of oxygen consumption is dependent upon incubation temperature and, after an initial lag phase, is exponential with time. Although rice seed can germinate and grow at low oxygen concentrations, germination is poor and seedlings exhibit low vigour. An oxidized zone may be observed around the seed when sown in an anoxic environment but coated with a layer of calcium peroxide. The seed germinates readily and develops normally when a sufficient level of calcium peroxide is used.     

微生物种子包衣的应用与研究进展

种子包衣是一种高效、新兴的种子处理技术。该技术将外源性材料与种子紧密结合,从而提高种子性能,最终提高作物产量和品质。植物有益微生物(plant beneficial microorganisms, PBM)是指能够促进植物养分吸收、增强其对生物和非生物胁迫的耐受力,并促进植物生长或减少农业化学投入的微生物。因此,PBM可以作为一种微生物种子包衣剂。微生物种子包衣作为一种能够显著提高作物产量、经济效益和农业系统的可持续性发展的革新性技术,因其生态安全性和社会经济效益被认为是传统农业技术有前途的替代品。本文综述了微生物种子包衣技术及其在作物生产中的应用,并对其局限性和不一致性进行讨论。     

Effect of lanthanum on aged seed germination of rice

Attempts were made to promote germination of natural aged rice seeds by treating them with lanthanum nitrate. In tests to measure the germination rate, germination index, and vigor index of natural aged rice seeds were found to be significantly increased by lanthanum. It is treating aged rice seed with lanthanum nitrate that enhanced the respiratory rate and activities of superoxide dismutase, catalase, and peroxidase, and decreased superoxide and malondidehyde contents, and therefore reduced plasma membrane permeability. It suggests that lanthanum may be used to pretreat seed before sowing.     

Enhancement of synthetic seed conversion to seedlings in hybrid rice

Somatic embryos of hybrid rice (Oryza sativa L.) were encapsulated in sodium alginate matrix provided with MS nutrients, growth regulators and protectants as synthetic endosperm to enhance germination and conversion capacity. The synthetic seeds with synthetic endosperm constituents of MS nutrient; sucrose (3%), IAA (0.5 mg l^–1), NAA (0.5 mg l^–1), BA (0.5 mg l^–1) and charcoal (1.25%) gave a maximum germination (30%) and conversion (27%) of synthetic seeds. The inclusion of protectants, bavistin and streptomycin as constituents of synthetic endosperm had no effect on germination and conversion. The application of self-breaking gel beads technology increased the germination (52%) and conversion (47%) of synthetic seeds.     

栽培稻种子含氮量的基因型差异

采用田间试验研究了421个常规籼稻、63个常规粳稻和82个籼型杂交稻品种种子含氮量的基因型差异。结果表明,栽培稻种子含氮量变幅在0.85%~2.55%,平均为1.39%。种子平均含氮量最高的是籼型杂交稻,高达1.46%,显著高于常规粳稻(1.39%)和常规籼稻(1.37%)。不同类型的栽培稻种子含氮量呈正态分布,但频数分布最高的区间存在一定的差异。以50%品种的种子含氮量(累积百分数从25%~75%)为依据,常规籼稻、常规粳稻、籼型杂交稻分别集中在1.21%~1.52%、1.21%~1.51%、1.36%~1.53%。LSR测验表明,籼型杂交稻极差显著小于常规籼稻和常规粳稻,但常规粳稻与常规籼稻的差异未达显著水平,即籼型杂交稻种子含氮量比常规籼稻和常规粳稻的分布更加集中。不同类型栽培稻内的种子含氮量极差较大,可分为若干组,且各组间达极显著差异。     

Evaluation of allergenic potential for rice seed protein components utilizing a rice proteome database and an allergen database in combination with IgE-binding of recombinant proteins

Among 131 rice endosperm proteins previously identified by MS-based proteomics, most of the proteins showed low or almost no sequence similarity to known allergens in databases, whereas nine proteins did it significantly. The sequence of two proteins showed high overall identity with Hsp70-like hazel tree pollen allergen (Cor a 10) and barley α-amylase (Hor v 16), respectively, whereas the others showed low identity (28–58%) with lemon germin-like protein (Cit l 1), corn zein (Zea m 50 K), wheat chitinase-like xylanase inhibitor (Tri a XI), and kinase-like pollen allergen of Russian thistle (Sal k 1). Immuno-dot blot analysis showed that recombinant proteins for these rice seed homologs were positive in the IgE-binding, but not necessarily similarity dependent, from some allergic patients. These results suggest that utilization of proteome and sequence databases in combination with IgE-binding analysis was effective to screen and evaluate allergenic potential of rice seed protein components.     

根表铁锰氧化物胶膜对不同品种水稻吸镉的影响

采用土培方法,研究了不同品种水稻吸镉的差异及其与根表铁锰氧化物胶膜的关系,结果表明：不同品种水稻其根膜,根部及地上部含镉量均存在显著性差异,且镉在不同水稻植株体内运输转移能力不同,不同水稻其根表淀积的铁锰氧化物数量也存在显著性差异,根膜及地上部的含镉量与极膜的含铁量均未达到显著性相关,但与根膜的含锰量相关性显著。     

Effects of salinity on seed set in rice

Salinity reduces fertility in rice (Oryza sativa L.), but little is known of the underlying cause(s). In order to determine the relative importance of pollen viability and stigmatic receptivity for seed setting, plants of the rice cultivar IR36 were treated with ‘artificial’ sea water (0,10, 25 or 5Omol^?3 with respect to NaCl) from 1 month after germination until the main tiller flowered. An increase in the salinity in the medium resulted in a decrease in the number of fertile florets and in the viability of pollen as determined both by pollen germination and by pollen staining with the tetrazolium salt 3-(4,5-dimethyl-ithyazolyl)-2,5-diphenyl monotetrazolium bromide. In order to assess the effects of salt on stigmas, seed production was measured for salt-grown and non-salt-grown female plants pollinated with viable pollen (from plants grown in the absence of salt). The percentage of seed set was reduced by 38% when the female plants were grown in 1Omol m^?3 Na and by 72% at 25mol m^?3 Na: no seed setting was recorded for plants grown in 50mol m^?3 Na. Comparisons between crosses involving male and female parents grown at different salinities indicated that effects on the female plants dominated those on pollinator plants. Mineral analysis of leaves of different ages showed that there was a gradient of K concentration from leaf to leaf which was opposite to that of Na and Cl at all levels of applied salinity: K was maximal in the flag leaf, where Na and Cl were minimal. Analysis also revealed that there was an increase in the concentrations of Na and Cl and a decrease in the concentration of K in the pollen grains and stigmas of plants subjected to saline conditions. Correlations between the concentration of Na and Cl in pollen and pollen staining and pollen germination in vitro suggest that Na and Cl perse were responsible for the poor viability. The change in ionic concentrations in pollen and stigmas was much larger than that in the younger leaves, and in particular very much larger than that in the lemmas and paleas.