干旱胁迫对两种过路黄抗性生理生化指标的影响

以过路黄和金叶过路黄为材料，通过盆栽干旱胁迫处理，同时以正常浇水为对照，研究了不同程度干旱胁迫对过路黄与金叶过路黄叶片的质膜透性、保护酶活性、渗透调节物质的影响。结果表明：在干旱胁迫下，过路黄与金叶过路黄叶片的质膜透性上升；超氧化物歧化酶（SOD）、过氧化物酶（POD）活性先上升，后下降；脯氨酸都有明显的增加。经对几项生理指标的综合分析，认为过路黄比金叶过路黄具有较强的抗旱能力。     

春季修剪对腾冲过路黄开花的影响

研究了春季2～3月不同修剪时间和次数对腾冲过路黄复制开花数、花枝数和枝条直径的影响,认为腾冲过路黄在2月份修剪1次即可,能使其保持更长时间稳定的开花数。如果要使花期延迟些,可再修剪1次,但是花枝直径会明显变小。修剪3次对腾冲过路黄的影响更大,会使开花枝数和开花总数显著减少,花枝直径显著变小。3月底腾冲过路黄开始进入花芽分化期,一般不宜对其进行修剪。     

黄茶感官闷黄程度标定及不同闷黄程度莫干黄芽香气组分研究

本实验通过控制不同的闷黄时间获得不同闷黄程度的黄茶样品25个,通过感官审评的方法对黄茶的闷黄度(0-10)进行标定。通过感官审评并结合闷黄度标定选取五个闷黄程度不同的莫干黄芽样品。利用可控温的同时蒸馏萃取法(SDE)提取香气物质,并结合气相色谱-质谱联用(GC-MS)技术进行香气组分及特征的比较。研究在五个莫干黄芽中共鉴定得出127种挥发性成分,闷黄程度较高的黄茶,其香气物质含量也相对较高。基于香气分组进行主成分分析(PCA)和正交偏最小二乘判别分析(OPLS-DA),探寻与闷黄程度相关的香气组分,发现闷黄程度与芳樟醇、苯乙醇、茉莉酮、苯甲醇、茉莉内酯、柠檬烯、紫罗兰酮、苯乙烯等34种香气物质与闷黄程度相关性较高。     

不同落黄类型小麦品种的籽粒灌浆及叶片光合特性

为给不同落黄类型小麦品种的选育提供理论依据,研究了不同落黄类型小麦品种籽粒灌浆和穗、茎、叶对籽粒灌浆的贡献。结果表明,早衰落黄型、灰白落黄型、全身落黄型小麦品种籽粒灌浆特性、叶片叶绿素含量变化和旗叶光合速率均存在较大差异。早衰落黄型和灰白落黄型品种旗叶和倒二叶叶绿素含量衰减发生早,下降速度快,旗叶光合速率低,籽粒物质积累在灌浆前中期多而后期较少;全身落黄型品种叶绿素含量衰减发生晚,下降速度缓慢,旗叶光合速率高,穗、茎、叶对籽粒灌浆的贡献率较大,籽粒平均灌浆速率高,籽粒饱满指数较高。因此认为,全身落黄型是小麦高产育种选择的重要指标。     

小麦黄花叶病对不同类型小麦品种生物学性状及籽粒产量的影响

为了给小麦科学防病和抗(耐)病品种的筛选提供参考依据,在小麦黄花叶病重发区,以当地种植品种和黄淮冬麦区主推品种为试验材料,研究了小麦黄花叶病对不同小麦品种叶片SPAD(Soil and Plant Analyzer Development)值、春季总茎数、干物质积累量以及成熟期产量性状的影响。结果表明,感病小麦品种临麦4号和矮抗58于起身期(3月11日)开始出现症状,与无症状的临麦4号植株(LM4-N)相比,发病的临麦4号植株(LM4-S)的叶片SPAD值由52.4降至37.3;拔节后期(4月10日)所有品种SPAD值之间均无显著差异。然而,与LM4-N相比,拔节后期LM4-S单位面积总茎数减少51.4%,干物质积累量降低42.2%;成熟期LM4-S单位面积穗数降低21.2%,穗粒数降低24.5%,籽粒产量降低2 944.3kg·hm-2,降幅38.3%。而该病对本研究中的其他抗病表现较好的品种鲁原502、济麦22、良星99和烟农24均未产生显著影响。结合各品种的产量表现,建议在小麦黄花叶病发病地区种植推广鲁原502、济麦22等高产、抗(耐)病性较好的品种。     

夏大豆苗黄的原因及防治技术

通过对夏大豆苗期发黄，生育迟缓现象进行了观察分析表明，豆苗发黄分生理性发黄和病理性发黄两种，其主要原因分别有缺乏微量元素、肥害（盐害）、土壤板结、大豆孢囊线虫病、大豆花叶病毒病等。几年的生产科研实践，探索出了一套综合防治方法，即选择良好的土壤、实行轮作，倒茬、增施有机肥、选用优良品种，种前整地，采取药肥拌肥、足墒旱播、合理密植，加强苗期管理。     

不同施肥水平对甘蓝型黄籽油菜含油量的效应研究

采用4因素正交旋转组合设计,研究了氮、磷、钾、硼施用量对供试品种渝黄1号和GH06种子含油量的影响.结果表明:1) 氮、磷、钾、硼养分因子对含油量均有较大影响;2)施用氮肥有降低含油量的作用,而钾、硼肥有提高含油量的作用,增施磷肥在一定范围内可以提高含油量,超出适宜范围则会降低含油量; 3)氮、磷肥水平之间有较显著的互作效应,并与土壤本身的理化性状有关.     

不同种类真菌多糖对小麦黄矮病的防治效果

为了筛选小麦黄矮病的真菌多糖防治药剂及其适宜浓度,将云芝、灵芝、虫草等13种真菌多糖稀释成0.1、0.5、1.0、2.0g·L-1溶液,以清水为对照,比较分析了叶面喷施真菌多糖对小麦黄矮病的预防和治疗效果,同时对防效好的1.1%云芝葡聚糖(多糖)与常规植物抗病毒药剂的田间防效进行了比较。结果表明,13种真菌多糖对小麦黄矮病的预防作用都显著高于治疗作用,且真菌多糖间和浓度间差异均显著,其中云芝多糖1.0g·L-1、云芝多糖2.0g·L-1、蜜环菌多糖2.0g·L-1、灰树花多糖2.0g·L-1、猪苓多糖2.0g·L-1的预防效果分别为86.88%、86.58%、86.33%、86.04%和85.97%。1.1%云芝葡聚糖800倍液为适宜喷施浓度,其防效64.27%,保产22.70%,说明云芝多糖是一种有前途的新型小麦黄矮病免疫抑制剂。     

不同遗传背景的甘蓝型黄籽油菜籽色遗传初步研究

以７种不同来源的甘蓝型黄籽油菜品系为材料,采用完全双列杂交试验和与中油８２１测交的方法,分析了粒色的遗传规律,初步结果显示：不同来源的甘蓝型黄籽油菜品系带有不同的粒色基因,有些为等位基因,有些属非等位基因。粒色遗传以加性效应为主,显性和上位性效应也很明显。     

灵香草总黄酮的提取及对羟自由基的清除效率

以灵香草为实验材料,利用超声波辅助乙醇提取灵香草黄酮。通过正交试验设计优化灵香草总黄酮的提取条件,并对黄酮提取物的抗氧化性进行研究。结果表明,灵香草黄酮的最佳提取工艺条件为:乙醇浓度70%、料液比1∶20、提取时间50 min、提取温度60℃。在此条件下,灵香草黄酮的平均提取率为3.27%。在相同质量浓度下,所提取的灵香草黄酮提取物对羟基自由基的清除率高于Vc,具有一定的抗氧化能力。     

武平县2个桉树品种前期生长及抗冻性

对武平县尾叶桉U6、巨尾桉DH3229 2个桉树品种前期（1、2和3年）生长及抗冻害能力进行了对比分析。结果表明：1年生尾叶桉U6的胸径、树高均极显著地大于巨尾桉DH3229;2年生巨尾桉DH3229抗冻害能力极显著地大于尾叶桉U6;3年生巨尾桉DH3229的胸径、树高均极显著地大于尾叶桉U6。综合2个桉树品种前期生长及抗冻害情况,武平县发展桉树速丰林宜选择巨尾桉DH3229。     

Freeze tolerance and physiological changes during cold acclimation of giant reed [Arundo donax (L.)]

Arundo donax L. (Poaceae), giant reed, is a rhizomatous shrubby grass that is cultivated in subtropical and warm temperate regions for a multitude of uses. Recently, it has been identified as a leading sustainable, non‐food crop for lignocellulosic biofuels due to its low ecological and agronomic demands. Lack of cold hardiness may limit its diffusion into colder areas of the transition zone. The objectives of this study were to (i) quantify freeze tolerance (LT₅₀) of cold‐acclimated and non‐acclimated Arundo donax L. plants using reproducible, controlled environment conditions, (ii) determine the effect of prolonged exposure to freeze stress on tolerance by keeping plants at a constant, sublethal temperature and (iii) study the relationship of non‐structural carbohydrates (total soluble sugars, glucose, fructose and sucrose) and proline accumulation with cold hardiness. In vitro‐propagated plants of the Honduran and Hungarian ecotypes of Arundo donax L. were chosen for this study. Cold acclimation treatment was imposed for 1 week using a controlled environment chamber set at 10°C and with a 12‐h photoperiod of 200 μmol m^?2 s^?1 photosynthetically active radiation. Freeze tolerance ranged from ?12·8°C (Honduran) to ?16·4°C (Hungarian ecotype). In all the organs analysed, total soluble sugars significantly increased during cold acclimation, with concentrations between 1·8‐ and 4·7‐fold higher than in non‐acclimated plants. The higher concentrations of sugars and proline in cold‐acclimated plants were positively associated with enhanced giant reed freeze tolerance (2·9°C lower). Our results confirm that during cold acclimation, metabolic changes related to increased freezing tolerance occur in giant reed.     

Effects of Neotyphodium endophytes on growth, reproduction and drought-stress tolerance of three Lolium perenne L. genotypes

Three Lolium perenne L. genotypes collected from different natural habitats were tested for the effects of their fungal endophyte Neotyphodium spp. on plant growth and seed yield. Half the clones of the originally infected plants were subjected to fungicide treatment to eradicate the endophytes. In an experiment, the clones were planted separately into pots and were either watered adequately or subjected to drought stress. In the genotype collected from a dry site, the endophyte infection reduced plant growth at an adequate water supply, but increased regrowth under drought. In the genotype from a periodically either flooded or dry site, endophyte infection significantly promoted the development of reproductive tillers and seed production (effects which are associated with adaptation to drought). In contrast, the genotype that originated from a wet site showed higher sensitivity to drought stress when endophyte infection was present. The results suggest that environmental conditions in the original habitat of the plants may influence the symbiotic interaction between plant and fungus, probably through natural selection. However, endophyte‐induced increases in root dry weight and root/shoot ratio were recorded for all three genotypes. These features could be beneficial for plant persistence, especially on sites where water is the growth‐limiting factor.     

低温胁迫等对割手密和斑茅叶片游离脯氨酸含量的影响

研究了诱导以甘蔗近缘野生种割手密、斑茅无性系的离体叶片等材料中的游离脯氨酸Fpro）积累的低温处理、蔗糖诱导方法等。结果表明,低温处理会引起叶片中Fpo含量增加,其中30℃低温处理时叶片中Fpo含量随处理时间延长而递增,而更低温处理只能引起Fpo含量短期内增加∶外施蔗糖溶液能增强低温处理的效果;割手密叶部是合成Fpo的主要部位,Fpo在叶部合成后迅速转运到茎和根。不同叶龄的叶片中Fpo 含量不同,衰老叶中Fpo含量最高,其次为新生叶,成熟叶最低,但衰老叶片中游离脯氨酸的积累与低温无关,测定 Fpro 含量的材料以成熟叶片为宜。     

不同因子对黄秋葵毛状根生长的影响

目的探讨不同因子对黄秋葵毛状根生长的影响。方法利用增殖倍数法测定毛状根的生长．从而明确各因子对黄秋葵毛状根的影响。结果3％蔗糖浓度最适宜毛状根的生长。0．5mg／L6-BA对毛状根有一定的抑制作用,0．5mg／LNAA、IAA对毛状根有一定的促进作用。尤其是0．5mg／LIAA培养的毛状根增殖倍数更为显著。MJA对毛状根生长有抑制作用,SA对毛状根的生长没有明显的影响。结论不同因子不同程度地影响了毛状根的生长,为进一步筛选适宜的黄秋葵毛状根培养体系奠定了基础。     

Study of water stress effects in different growth stages on yield and yield components of different rice (Oryza sativa L.) cultivars

A field experiment was conducted during 2001-2003 to evaluate the effect of water stress on the yield and yield components of four rice cultivars commonly grown in Mazandaran province, Iran. In northern Iran irrigated lowland rice usually experiences water deficit during the growing season include of land preparation time, planting, tillering stage, flowering and grain filing period. Recently drought affected 20 of 28 provinces in Iran; with the southeastern, central and eastern parts of the country being most severely affected. The local and improved cultivars used were Tarom, Khazar, Fajr and Nemat. The different water stress conditions were water stress during vegetative, flowering and grain filling stages and well watered was the control. Water stress at vegetative stage significantly reduced plant height of all cultivars. Water stress at flowering stage had a greater grain yield reduction than water stress at other times. The reduction of grain yield largely resulted from the reduction in fertile panicle and filled grain percentage. Water deficit during vegetative, flowering and grain filling stages reduced mean grain yield by 21, 50 and 21% on average in comparison to control respectively. The yield advantage of two semidwarf varieties, Fajr and Nemat, were not maintained under drought stress. Total biomass, harvest index, plant height, filled grain, unfilled grain and 1000 grain weight were reduced under water stress in all cultivars. Water stress at vegetative stage effectively reduced total biomass due to decrease of photosynthesis rate and dry matter accumulation.     

不同采收期辽东丁香枝中黄酮和多糖含量的比较研究

目的测定不同采收期辽东丁香枝中黄酮及多糖的含量．对辽东丁香枝的质量进行综合评价。方法采用比色法测定黄酮及多糖含量。以芦丁和葡萄糖为对照品,在500nm波长下测定吸光度,测定黄酮的含量,在620rim波长下测定总多糖吸光度,分别测定可溶性多糖和粗多糖的含量。结果在0．15mg-1．5mg范围内,芦丁质量与吸光度A值线性关系良好,R2=0．9999;在0．04mg,．-0．20rag范围内,葡萄糖质量与吸光度A值线性关系良好R2=0．9974。黄酮在3月25日含量最高为8．52％,总多糖在9月4日含量最高为12．67％。结论通过T-TEXT比较不同采收期辽东丁香枝中的总黄酮和多糖含量,差异显著,黄酮随着多糖的增加呈上升的趋势。本方法简便、快速、可靠、适合辽东丁香黄酮及多糖的含量测定。