反胶束法萃取核桃胰蛋白酶抑制剂及其抗虫研究

植物胰蛋白酶抑制因子对植物本身具有保护作用,能调节植物蛋白质的合成和分解,并具有抗虫作用。为明确核桃蛋白酶抑制剂对小菜蛾的抗虫效果,该研究采用AOT/异辛烷反胶束法和亲和层析法萃取及纯化核桃胰蛋白酶抑制剂,命名为WTI,并对其抑制活性和生物活性进行测试。迪克森作图法测得纯化的核桃胰蛋白酶抑制剂的抑制常数为2.1×10-9mol/L。抗虫试验表明,小菜蛾自1龄起至化蛹前的整个幼虫阶段中,核桃胰蛋白酶抑制剂均对其产生了较强的毒杀作用。尤其是在1-3龄期,效果最佳。与对照组相比,WTI能延迟小菜蛾的化蛹时间,降低其化蛹率。核桃胰蛋白酶抑制剂对小菜蛾有明显的毒杀作用,但不表现出明显的生长抑制作用,且一定浓度的核桃胰蛋白酶抑制剂能将小菜蛾扼杀在其化蛹之前,从而能够控制其繁殖。     

浅谈芽苗砧嫁接技术

浅谈芽苗砧嫁接技术王玉欣（山东省沂南县第四中学,２７６３００）芽苗砧嫁接是项新技术。就是以尚未展叶或刚展叶的芽苗作砧木,嫁接所需繁殖对象的一项无性繁殖新方法。近十几年来,该项技术在我们沂蒙山区先后在核桃、山茶、板栗、银杏等多种树木的良种繁殖中取得了成...     

核桃分子生物学研究进展

核桃与扁桃、腰果、榛子并列为世界四大干果,具有重要的经济价值和基础研究价值。分子生物学及基因工程技术的发展为核桃基础理论研究提供了新的技术手段。从分子水平综述了核桃过敏原和其引发过敏症的机理、再生长期糖运输和叶片水分运输的调控、组织培养技术的发展和利用转基因技术来培育核桃新材料的现状、核桃种质资源的遗传分析研究进展,并对核桃的研究前景进行了展望。     

新疆野核桃种质对低温胁迫的生理响应

以新疆巩留野核桃林37份新疆野核桃种质资源的1年生枝条为材料,6份核桃楸为对照,利用人工气候箱模拟春季低温,分别于-20 ℃和4 ℃处理12 h,测定其相对电导率、游离脯氨酸、可溶性糖、丙二醛含量、过氧化物酶活性等生理生化指标,并进行相关分析。采用隶属函数和主成分分析综合评价核桃种质对低温的生理响应。结果表明: 低温胁迫下,新疆野核桃相对电导率、游离脯氨酸含量、可溶性糖含量、丙二醛含量和过氧化物酶活性均呈上升趋势。综合评价其低温抗性与生境相关:巩留野核桃林中沟>东沟>西沟>主沟。新疆野核桃表现出比核桃楸更为耐低温的特性。本研究从37份新疆野核桃种质中筛选出7份耐低温种质,为改良核桃品种和提高核桃耐倒春寒等生长期的突然天气变化的能力提供科学参考。     

四川核桃良种SSR指纹图谱构建及遗传多样性分析

为构建四川核桃良种指纹图谱,分析遗传多样性,增强品种间的区分能力,该研究利用SSR标记技术,对四川29个核桃良种进行遗传多样性和聚类分析。结果表明:(1)11对SSR引物共检测到121个基因型和80个等位基因,平均每个位点7.273个等位基因和11个基因型。(2)11个位点的平均有效等位基因数为3.644,平均观察杂合度为0.645,平均期望杂合度为0.718,平均香农信息指数为1.518,平均多态信息含量为0.680。(3)采用引物组合法利用引物wga001、wga032和zmz02构建了29个核桃品种的指纹图谱。(4)聚类分析结果表明,29个核桃品种按照品种类型优先聚类,四川本地核桃品种聚类关系与地理来源没有明显的相关性。研究认为,选用的11个SSR标记能够较好地运用于四川核桃品种的遗传多样性研究(PIC0.5);29个四川核桃品种间亲缘关系较近,遗传基础相对较窄。     

核桃实生居群遗传多样性ISSR分析

利用ISSR技术对新疆核桃元丰、云新核桃、泰山野核桃和陕西核桃4个核桃实生居群共61份种质进行了遗传多样性分析.结果表明:从36条ISSR引物中筛选9条引物,共检测出101个位点,多态性位点89个,占检测位点总数的88.12％,有效等位基因数、Nei's基因多样性指数和Shannon信息指数分别为1.5207、0.3125和0.4759.UPGMA聚类结果表明,61份核桃种质聚为5组,元丰核桃居群和陕西核桃首先聚在一起,然后与云新核桃聚在一起,最后与泰山野核桃相聚,其中陕西核桃居群的遗传多样性最高,分为2组,其多态位点百分率、H值和I值分别为66.29％、0.2111和0.3239.居群间遗传一致度在0.6727 ～0.7970之间,基因流为0.4220,表明不同居群间基因交流程度很低,基因分化明显,在遗传组成上存在显著差异.     

云南漾濞娘青核桃果仁主要营养评价

测定娘青核桃坚果及果仁的主要营养成分,并对油脂脂肪酸和蛋白质氨基酸进行综合评价,以期为娘青核桃加工利用提供科学依据。在娘青核桃主产区采集样品,对果仁主要内含营养物质脂肪酸、氨基酸、矿质元素等进行测量分析。娘青核桃果仁粗脂肪含量为60.6%,油脂SFA∶MUFA∶PUFA为1∶4∶7。蛋白质含量为20.8%,必需氨基酸指数（EAAI）为34.14。通过对粗脂肪、蛋白质、矿物质元素、脂肪酸等营养成分分析,亚油酸、亚麻酸的比例符合健康食用油的标准,蛋白质含量较高,在精深加工方面具有很高的利用价值。     

基于SRAP分子标记新疆野核桃的遗传多样性分析

利用SRAP分子标记技术对新疆野核桃遗传多样性进行分析。通过筛选出的15对具有多态性的SRAP引物组合进行PCR扩增,得到新疆野核桃遗传分化系数Gst为0.1152,说明新疆野核桃的遗传变异绝大部分存在于区域内部,占总变异的88.48%;多态位点百分率为94.07%,Shannon's信息指数I=0.4954,等位基因平均数Na=1.9454,表明新疆野核桃具有较高的遗传多样性;各区域间遗传相似系数在0.8981~0.9496之间,遗传距离在0.0553~0.1075之间,说明新疆野核桃资源间存在着丰富的遗传变异。通过聚类分析可聚为2类,进一步明确了新疆野核桃各区域之间的亲缘关系。     

华北石质山区核桃-绿豆复合系统氘同位素变化及其水分利用

通过对比核桃枝条和绿豆茎内δD值差异来分析核桃和绿豆水分来源和利用。结果表明,核桃-绿豆农林复合系统的根系在表层土壤(0—30cm)中交叉存在,生态位重叠。旱季中表层土壤含水量与δD值之间存在显著的负相关关系(R2=0.77,P=0.02),雨季相关关系不显著(R2=0.03,P=0.73)。δD值分析表明,旱季中核桃利用深层土壤(30—80cm)水分占总水分来源的51%以上,雨季中则主要利用浅层土壤水分,间作绿豆和单作绿豆主要利用表层土壤水分。雨季中表层土壤水分能同时满足核桃和绿豆生长需要,但复合系统中光能竞争导致间作绿豆光合速率显著地低于单作绿豆。旱季间作绿豆0—20cm土壤水分含量、凌晨叶片水势和光合速率明显高于单作绿豆,显示间作绿豆体内水分状况好于单作绿豆。线性模型分析结果显示间作绿豆体内约有1.58%—5.39%的水分来核桃夜晚水力提升,表明复合系统在旱季一定程度上缓冲季节性水分胁迫对农作物生长的影响。     

核桃叶多酚含量的测定和抗氧化能力的研究

核桃又称胡桃,全身是宝,除核桃仁可以直接食用外,其青皮、叶、枝、花、壳等均可入药,具有重要的经济和药用价值。为了进一步开发和利用核桃属植物资源,该研究以核桃叶为材料,采用Folin-酚法,测定核桃叶75%乙醇提取物及石油醚、乙酸乙酯、正丁醇萃取后的各部分多酚的含量,通过DPPH·和ABTS·自由基清除法评价其抗氧化能力,并分析多酚含量与抗氧化能力的关系。结果表明:核桃叶提取物及其各萃取部分均表现出一定的抗氧化活性,其中乙酸乙酯部分、正丁醇部分的IC_(50)均高于VC,核桃叶75%乙醇粗提物(Ext.)与VC相当,且多酚的含量和抗氧化能力呈现正相关关系。这说明核桃叶的提取物可以作为天然的抗氧化剂应用于食品、医疗、化妆品、保健品等行业。该研究结果为进一步开发利用核桃资源和提高核桃的经济效益提供了一定的理论基础。     

In vitro clonal propagation of Chlorophytum borivilianum Sant. et Fernand., a rare medicinal herb from immature floral buds along with inflorescence axis

A novel method of shoot regeneration from immature floral buds along with inflorescence axis in C. borivilianum, a rare medicinal herb is described. Using this explant, axenic cultures were established with very less contamination (10%). MS medium with 2 mg l(-1) kinetin and 0.1 mg l(-1) 2, 4-dichlorophenoxyacetic acid proved to be the best for multiple shoot induction. Maximum number (35) of shoot production was achieved in MS medium with 2 mg l(-1) benzylaminopurine. Rooting of shoots (86.7%) with maximum fasciculated roots (5) occurred on Knops medium containing iron and vitamins of MS medium with 2 mg l(-1) indole-3-butyric acid and 0.1% activated charcoal. Plant survival was 80% in four weeks after their removal from in vitro conditions. Per explant 34 hardened plants generated within 50 weeks. This protocol can be useful for large-scale clonal multiplication from immature floral buds with inflorescence axis and successfully used for germplasm conservation of this rare medicinal herb without destroying the mother plant.     

Direct plant regeneration from cucumber embryonal axis

Embryonal axis explants from 2-d-old in vitro germinated seeds were used to induce multiple shoot production. The combination of 4.44 μM BA and 1.59 μM NAA in MS medium triggered the initiation of adventitious shoot buds. The explants with shoot buds produced maximum number of shoots (10.6 per explant) in MS medium supplemented with 4.44 μM BA and 0.065 mM L-glutamine in three successive transfers. The elongated shoots were rooted on MS medium with 4.92 μM IBA. Rooted plants were transferred to soil with a survival rate of 65 %.     

Plant regeneration from seedling explants of green bean (Phaseolus vulgaris L) via organogenesis

Green bean (Phaseolus vulgaris L.) plants were regenerated from 3-day old seedling explants via organogenesis. The explants contained a cotyledon and a small portion (2–3 mm) of embryonic axis split in half. Explants were cultured on a defined medium containing glutamine as the sole nitrogen source. A ring of meristematic tissue was produced at the base of the axillary bud located at the cotyledonary node. The meristematic tissue was produced only if the axillary bud was present together with the cotyledon in the explant. Buds and shoots developed from the meristematic ring. Selected shoots produced roots when excised from the cluster of buds and transferred to root induction medium. Rooted shoots (plantlets) grew well and produced viable seeds when grown in the greenhouse. Histological studies revealed the origin of buds from the peripheral layers of the meristematic ring.Production of buds and shoots was a continuous process, so that new shoots could be removed from the explant for plantlet production every 10–14 days. With the cultivar Dark Red Kidney, an average of 49 buds and 8 shoots were regenerated per explant by 30 days after culture initiation. Sixty-seven percent of the shoots produced roots, and 90–95% of the plantlets survived greenhouse acclimatization to produce healthy plants.     

Morpho-histological characterization and direct shoot organogenesis in two types of explants from <Emphasis Type="Italic">Bacopa monnieri</Emphasis> on unsupplemented basal medium

In the present study, high frequency regeneration has been obtained via de novo direct shoot organogenesis from leaf and internode explants in Murashige and Skoog (MS) basal medium without any phytohormone supplementation in Bacopa monnieri, an indigenous traditionally used medicinal herb. Leaves and internodes from different positions were excised from 4-weeks-old in vitro propagated B. monnieri plants and cultured on MS basal medium supplemented with 3% (w/v) sucrose and 0.75% (w/v) agar for 4 weeks. The induction of de novo shoot buds was observed at petiolar cut edges of leaf and both proximal and distal cut ends of internode explants within 10–15 days of culture. The first histological changes could be observed after 4–5 days, with meristematic activity of vascular bundles. Proliferation of epidermal cells gave rise to dome-shaped protuberances followed by shoot apical meristems formation and their vascular connections with explant tissues within 2 weeks of culture. However, a basipetal gradient of shoot regeneration from both types of explants collected along the branch axis was noticed after 4 weeks of culture. Leaf and internode explants near the basal region exhibited significantly higher number of shoot buds and micro shoots (8.8/leaf explant and 15/internode explant). Microshoots (7–12 micro shoots/leaf or internode explants) elongated (shoot length 8–9 cm) within 8 weeks on phytohormone free MS medium. Excised micro shoots rooted (100%) in hormone free MS medium within two weeks of culture. Rooted plants were then acclimatized and transferred to field with 95% survival. This protocol may be used for micropropagation, genetic transformation as well as a model system for evaluation of changes associated with acquisition of competence of differentiated cells in phytohormone free medium.     

Influences of medium consistency and shoot density on in vitro shoot proliferation of Populus alba × P. grandidentata

The in vitro shoot proliferation of Populus alba × P. grandidentata was affected by the medium consistency and shoot density, but not by three sizes of vessels. After 4 weeks of culture, the fresh weight and number of shoots per explant on liquid medium were significantly greater than those on agar-solidified medium. In particular, 3.2 shoots, 7 mm or longer per explant, were produced on liquid medium compared with 1.6 shoots per explant or agar-solidified medium. The fresh weight per explant after 4 weeks of culture on liquid medium and agar-solidified medium were 0.68 and 0.25 g, respectively. Increasing the number of shoots per vessel slowed the growth of the explants as measured by fresh weight and the number of shoots produced. There was little difference in the number of shoots produced between vessels with 1 or 2 shoots per vessel, but there were many fewer shoots produced when 3 shoots were placed in each vessel.Journal Paper No. J-11977 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project 2210.     

High frequency somatic embryogenesis in peanut (Arachis hypogaea L.) using mature,dry seed

Peanut (Arachis hypogaea L.) somatic embryos were produced from the embryo axes of mature, dry seeds of cultivar GK-7. Percent embryogenic explants ranged from 88–100% using 10–40 mg/1 of 2,4-D in the induction medium. Neither 2,4-D concentration nor photoperiod during the induction period had a large effect on percent embryogenesis, mean number of embryos per explant, or embryo morphology. However, embryos obtained from cultures grown in the dark were easier to remove from the explant than those under a 16-h photoperiod. Somatic embryos developed on the epicotyl portion of the embryo axis, primarily on the young, expanding leaves. A survey of 14 genotypes indicated that genotype had a large influence on embryogenic capacity, with all genotypes being embryogenic to some extent. The ability to recover somatic embryos from axes of harvested, stored seeds represents significant advantages for the establishment of peanut embryogenic cultures, including the use of simple sterilization procedures and a constant source of explant tissue.Abbreviations B5 medium of Gamborget al. (1968) - 2,4-D 2,4-dichlorophenoxyacetic acid - MS Murashige and Skoog (1962) salts medium     

亳芍茎尖组织培养的研究

选取亳芍茎尖为试验材料,探究不同培养条件对亳芍组织培养的影响,结果表明:亳芍茎尖在1/2MS+6-BA 1.0 mg/L培养基上培养39 d后,茎尖分化出芽的同时也形成较多的丛生芽;丛生芽在1/2MS+6-BA1.0mg/L培养基上增殖速度最快;来自不同启动培养基上的丛生芽在相同培养基上,接种15 d后观察,不同来源的丛生芽长势不同,30 d后仍存在一定的差异;幼苗在1/2MS+IBA 0.1生根效果最好。     

“葡萄状核桃”和普通核桃的过氧化物酶同工酶的比较研究

用聚丙烯酰胺凝胶电泳技术测定了葡萄状核桃和普通核桃６种组织的过氧化物酶同工酶。分析比较了两种核酶谱和酶活性的异同。结果表明,葡萄状核桃除当年生果枝外,其它各组织中的过氧化物酶活性均低于普通核桃。葡萄状核桃雄花轴,雌花和雄花中酶带的数目也比普通核桃相应组织为少。     

Thidiazuron-induced high-frequency plant regeneration from leaf explants of Paulownia tomentosa mature trees

Attempts were made to study the effect of thidiazuron (TDZ) on adventitious shoot induction and plant development in Paulownia tomentosa explants derived from mature trees. Media with different concentrations of TDZ in combination with an auxin were used to induce adventitious shoot-buds in two explant types: basal leaf halves with the petiole attached (leaf explant) and intact petioles. Optimal shoot regeneration was obtained in leaf explants cultured on induction medium containing TDZ (22.7 or 27.3 μM) in combination with 2.9 μM indole-3-acetic acid (IAA) for 2 weeks, and subsequent culture in TDZ-free shoot development medium including 0.44 μM BA for a further 4-week period. The addition of IAA to the TDZ induction medium enhanced the shoot-forming capacity of explants. The caulogenic response varied significantly with the position of the explant along the shoot axis. The highest regeneration potential (85–87%) and shoot number (up to 17.6 shoots/explant) were obtained in leaf explants harvested from the most apical node exhibiting unfolded leaves (node 1). An analogous trend was also observed in intact petiole explants, although shoot regeneration ability was considerably lower, with values ranging from 15% for petioles isolated from node 1 to 5% for those of nodes 2 and 3. Shoot formation capacity was influenced by the genotype, with regeneration frequencies ranging from 50% to 70%. It was possible to root elongated shoots (20 mm) in basal medium without growth regulators; however, rooting frequency was significantly increased up to 90% by a 7-day treatment with 0.5 μM indole-3-butyric acid, regardless of the previous culture period in shoot development medium (4 or 8 weeks). Shoot quality of rooted plantlets was improved not only by IBA treatment but also by using material derived from the 4-week culture period. Regenerated plantlets were successfully acclimatized in the greenhouse 8 weeks after transplanting.     

High efficiency plant regeneration and genetic fidelity of regenerants by SCoT and ISSR markers in chickpea (Cicer arietinum L.)

High efficient and repeatable in vitro regeneration protocol was established from embryo axis, half-seed, axillary meristem, and cotyledonary node explants of chickpea. Various concentrations and combinations of various plant growth regulators (PGRs) were employed to induce multiple shoots, shoot elongation and rooting of shoots to obtain complete plantlets of chickpea. The pretreatment of seeds with 6-benzyl aminopurine (BAP) at 1.0 mg l^?1 was found to significantly increase the multiple shoot regeneration from the all explants tested. Among three PGRs such as BAP, kinetin (KIN) and thidiazuron (TDZ) tested for multiple shoot induction; BAP at 2.0 mg l^?1 produced the maximum number of shoots in all tested explants. The maximum number of shoots (48.80 shoots/explant) was attained from the embryo axis explant followed by half-seed (32.76 shoots/explant), axillary meristem (28.34 shoots/explant) and cotyledonary node explant (18.47 shoots/explant) on medium augmented with 2.0 mg l^?1 BAP along with 0.05 mg l^?1 Indole-3-butyric acid (IBA). The optimum percentage of shoot elongation response was recorded (96.68%) on medium fortified with IAA (0.05 mg l^?1), GA₃ (1.0 mg l^?1) and BAP (1.0 mg l^?1) with an average shoot length of 8.82 cm. The elongated shoots were successfully rooted in medium augmented with 2.0 mg l^?1 IBA. The complete plants were acclimatized in the greenhouse with a survival rate of 72%. The plantlets regenerated from four explants appeared to be morphologically similar to mother plants. The genetic fidelity of in vitro regenerated plants was evaluated using Start Codon Targeted and Inter simple sequence repeats molecular markers. The in vitro regenerated plants from all four explants were found to be the true to type with their mother plant. The in vitro protocol presented in the study should offer as a feasible system for chickpea genetic transformation.