大白菜雄性不育系小孢子发生的细胞形态学研究

  采用塑料半薄切片技术, 在光学显微镜下系统地观察了大白菜同质异核、异质同核细胞质雄性不育系、细胞核雄性不育系及其相应保持系花药发育过程的细胞形态学特征。研究结果表明: 细胞核雄性不育系花药败育主要发生在减数分裂期, 花粉母细胞不能发生正常的减数分裂; 细胞质雄性不育系花药败育主要发生在四分体时期或小孢子单核期, 表现为绒毡层细胞异常, 四分体或小孢子败育。     

菜薹细胞质不育系小孢子发生的细胞形态学研究

菜薹雄性不育系小孢子发生的细胞形态学观察表明，孢原细胞分化期之前败育的花占５９．６％，不形成花粉囊；有花粉囊发育的花占４０．４％，其中绝大多数花中只有一个雄蕊能形成一个体积很小的花粉囊，雄性不育系小孢子发育在小孢子母细胞期、四分体及单核小孢子期均有败育，败育方式有绒毡层细胞异常肥大，挤压小孢子母细胞；减数分裂异常，无胞质分裂而形成巨细胞；单核小孢子粘连成花粉块，异常膨大等。还有雄蕊雌蕊化等花器异常现象。     

大葱雄性不育系及保持系花药和花粉发育的细胞学比较研究

为了从细胞学角度研究大葱雄性不育的机理,利用石蜡切片法对大葱雄性不育系及保持系花药与花粉发育过程进行比较研究。观察结果表明:大葱雄性不育系和保持系的小孢子母细胞都能正常进行减数分裂,四分体可以释放出小孢子。雄性不育系的花粉败育发生于单核小孢子时期,具有单核败育的特征。观察发现大葱雄性不育系的小孢子有2种败育类型:(1)绒毡层细胞正常发育,但中层细胞发生了延迟解体的现象,小孢子时期仍然存在,与逐渐缩小的药室一起挤压小孢子细胞成一染色极深的团块状物质;(2)绒毡层提前解体,不能提供小孢子发育所需的营养,小孢子的细胞质和细胞核逐渐解体,仅剩下内空的花粉粒。花粉败育不仅与绒毡层有关,还与中层细胞密切相关。     

番茄小孢子发育及其花粉败育的细胞学研究

我们采用石腊切片和细胞学压片技术,首次较详尽地研究了番茄小孢子发生和雄配子体发育的细胞形态学过程,续而又研究了番茄雄性不育系(花粉败育型,品系72—1)花药组织和小孢子的异常现象、不同发育时期的败育程度和败育原因等问题.结果发现: 1.番茄小孢子的发生从孢原细胞开始,经过造孢细胞、小孢子母细胞、四分体、小孢子和雄配子体等发育阶段,最后形成二核花粉。番茄的绒毡层细胞属于变形绒毡层类     

辣椒雄性不育系小孢子发生的细胞学观察

辣椒雄性不育系小孢子发育过程的细胞学观察表明，雄性不育系小孢子败育发在四分小孢子形成以前。由于绒毡层细胞发育异常，高度液泡化，挤压小孢子母细胞，严重影响了减数分裂的正常进行，不能形成正常花粉粒而导致败育。辣椒雄性不育系的花器明显小于保持系，前者成熟花药瘦小，干瘪，无花粉粒或花粉粒极少，花粉粒磺化反应不着色或着色极淡。扫描电镜下观察：辣椒雄性不育系的共粉粒表面光滑，无明显乳状突起，保持系花粉粒则有明     

枣树雄性不育新种质的获得

 通过测定花粉生活力、花粉量并结合解剖学观察, 首次从枣树自然群体中鉴定得到了1个黄蕾无花粉的雄性不育材料枣雄性不育1号。在雄性不育1号花粉发育过程中可见四分体, 之后小孢子聚集解体, 至黄蕾期花药空囊或仅留花粉残迹, 其花粉败育发生在四分体以后。四分体时期绒毡层肥大增厚可能与花粉败育有关。雄性不育1号胚中度可育、大果和早熟, 可以作为枣树杂交育种中有价值的母本材料。     

萝卜雄性不育系小孢子发生的细胞形态学研究

对秋冬萝卜雄性不育系６４Ａ及其保持系６４Ｂ小孢子形态发生中不同发育时期的花药和小孢子的观察表明，不育系中从四分体初释放的单核小孢子与正常者无可见差异；当单核小孢子内开始出现小液泡时即呈现败育：胞质淡染，外粉壁薄，整个小孢子停止膨大；随后其细胞核染色浅或仅见微小核仁。不育系绒毡层细胞高度液化使细胞迅速膨大而被挤向药室腔且延迟解体。败育的小孢子与异常的绒毡层最终粘连成团块并消失。用扫描电镜对开花期花药的观察，显示确无花粉。因此，该不育系是无花粉型不育系。     

红菜薹栽培与育种研究进展(下)

②雄性不育系的利用田福发等(2004)采用石蜡切片技术,在光学显微镜下系统研究了红菜薹波里马胞质雄性不育系(Polima CMS)、红菜薹萝卜胞质雄性不育系(Ogura CMS)及相应保持系花药发育过程的细胞形态学特征.观察结果表明,红菜薹Polima CMS花药发育受阻于孢原细胞阶段,不形成花粉,属无花粉型,此不育系花药不形成绒毡层和中层;而红菜薹Ogura CMS花药败育发生于小孢子母细胞期或四分体时期,表现为绒毡层细胞异常,挤压四分体,导致四分体和绒毡层同时解体而败育.     

西瓜雄性不育类型的遗传学鉴定与胚胎学观察

为了明确西瓜雄性不育材料的不育类型和花药败育时期,以西瓜雄性不育系GMS4为材料,对花蕾不育性状进行田间观察统计,利用石蜡切片法观察西瓜花药发育过程。结果表明,该材料不育性状由1对隐性基因控制,为细胞核雄性不育类型。可育株雄蕊发育正常,不育株雄蕊较小,花药干瘪无花粉,可育株和不育株雌蕊发育无明显差异,均可正常结瓜。从花药发育的整个过程来看,在花药发育早期,可育株和不育株花药结构形态差别不大,在小孢子母细胞减数分裂期,不育株异常绒毡层细胞过度增殖,体积小,排列不整齐,挤压药室,无二分体和四分体形成,在花药发育后期,无花粉粒形成,最终导致西瓜雄性不育发生。据此认为,花药败育发生时期在小孢子母细胞减数分裂期。     

新梨7号小孢子败育的解剖学观察

以梨雄性不育品种新梨7号为试材,解剖观察了其小孢子囊及雄配子发生发育的全过程。结果表明:新梨7号花药雏形已于上年生长季形成,次年2月中旬雄蕊原基休眠即可解除,早春气温是解除休眠的主导因子。新梨7号小孢子母细胞的减数分裂主要发生在3月中旬。在单核花粉粒形成之前,其小孢子母细胞减数分裂和四分体从药室组织中游离出来的过程完全正常。此后,单核花粉开始解体消失,其败育途径不同于多倍体梨减数分裂时染色体行为异常导致的败育。单核花粉的解体与药壁绒毡层细胞在发育后期增大、液泡化有关,是绒毡层机能障碍的结果。初步认为该品种败育属胞质雄性不育类型(CMS)。     

Ergebnisse der Leistungsprüfungen der Süßkirschensorte ‚Stella‘ auf Gisela- und Weiroot-Unterlagen in Bulgarien

Zusammenfassung Die Leistungsprüfungen wurden im Zeitraum 1997 bis 2003 mit den Unterlagen Gisela 4 und 5, den Klonnummern 195/20 und 497/8 aus der Gisela-Serie sowie Weiroot 10, 13, 53, 72 und 158 durchgeführt. Dabei dienten Sämlinge von P1 (bulgarische Selektion aus Prunus mahaleb) als Kontrolle. Alle Unterlagen waren mit der Sorte Stella veredelt und im Dezember 1996 in der Versuchsanlage der Agraruniversität in Plovdiv, Bulgarien, im Abstand von 6 m×4,5 m gepflanzt worden. Dabei erfolgte ein Pflanzschnitt. Nach Abschluss der natürlichen Kronenentwicklung wurde jedes Jahr ein Winterschnitt vorgenommen. Der Boden wurde durch mechanische Bearbeitung offen gehalten und nach dem 4. Standjahr wurden die Baumstreifen mit Herbiziden behandelt. Die Wasserversorgung erfolgte durch eine dem natürlichen Gefälle folgende Überflutung, allerdings nicht immer zum optimalen Zeitpunkt, da keine eigene Wasserquelle zur Verfügung stand.Basierend auf den Ergebnissen bis zum Anfang des 7. Standjahres können die untersuchten Unterlagen in zwei Gruppen differenziert werden: starkwüchsig—Weiroot 10, P1 und Weiroot 13; mittelstarkwachsend bis schwachwüchsig—Gi 497/8, Gisela 4, Weiroot 53, Weiroot 158, Gi 195/20, Weiroot 72 und Gisela 5. Letztere zeichnete sich durch besondere Schwachwüchsigkeit aus. Die meisten Wurzelschosser bildeten Gisela 4, Weiroot 10 und Weiroot 13. Weiroot 53, Weiroot 72 und Weiroot 158 entwickelten deutlich weniger und P1, Gisela 5, Gi 195/20 sowie Gi 497/8 keine Wurzelschosser. Den frühesten Blühbeginn induzierte Gisela 4. Die anderen Unterlagen führten, in Abhängigkeit von den Temperaturbedingungen des jeweiligen Jahres, zu einer Verspätung der Blüte: P1 und Weiroot 10 um 1–2 Tage; Gi 497/8, Weiroot 13 und Weiroot 158 um 2–4 Tage; Weiroot 72 um 2–7 Tage; Gi 195/20 um 3–6 Tage; Weiroot 53 um 3–8 Tage und Gisela 5 um 3–10 Tage. Die Reifezeit der Früchte war bei den Bäumen auf Gisela 5 im Vergleich zu den anderen Varianten um 2–3 Tage verspätet. Gisela 5, Weiroot 72 und Gisela 4 induzierten bei der aufveredelten Sorte die höchsten Ertragsleistungen, P1 die geringsten. Bei den Bäumen auf Gisela 5 war die Fruchtgröße geringer als bei den anderen Unterlagen. Bäume auf Gisela 5 brauchen intensive Pflege. Nur wenn alle Produktionsfaktoren und kulturtechnischen Maßnahmen optimiert werden, kann das hohe Ertragspotenzial dieser Unterlage ausgeschöpft werden.     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

Effect of L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.     

Effect of puerarin on pulmonary arterioles wall collagen metabolism of chronic hypoxia hypercapnia rats

AIM:To investigate the effect of puerarin on pulmonary vessel collagen metabolism in pulmonary hypertension rats induced by chronic hypoxia and hypercapnia.METHODS:Collagen Ⅰ, Ⅲ and their mRNA were observed in pulmonary arterioles by the technique of immunohistochemistry and in situ hybridization.RESULTS:① Light microscopy showed media thickness of pulmonary arterioles was much higher in HH(hypoxic-hypercapnia) group than that of NC(normal control) group, and, vessel cavity turned more straiter in HH group than that of NC group.However, the damage of pulmonary arterioles in HP(hypoxic-pueratin) group was much slighter than that of HH group. ② The levels of plasma ET-1 and lung homogenates Hyr were much higher in HH group than those of NC group(P＜0.01), and lower in HP group than HH groups(P＜0.01).Plasma NO content in group HH was lower than that of group NC(P＜0.01), it was higher in group HP than that of group HH(P＜0.01).③Expression of collagen Ⅰ and collagen Ⅰ mRNA in pulmonary arterioles were significantly higher in HH groups than those of NC group (P＜0.01), and they were lower in HP group than those of HH group (P＜0.01).Expression of collagen Ⅲ and collagen Ⅲ mRNA showed no difference among three groups(P＞0.05).CONCLUSION:Puerarin inhibited the deposition of collagen and improved pulmonary vessel remodeling.     

Relationship between renal hypertension and cardiac α1-adrenoceptor autoantibodies in rats

AIM: To examine the autoantibody against α₁-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α₁-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α₁-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α₁-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.     

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

Abstract

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.     

Multi-scale landscape and seascape patterns associated with marbled murrelet nesting areas on the U.S. west coast

Habitat for wide-ranging species should be addressed at multiple scales to fully understand factors that limit populations. The marbled murrelet (Brachyramphus marmoratus), a threatened seabird, forages on the ocean and nests inland in large trees. We developed statistical relationships between murrelet use (occupancy and abundance) and habitat variables quantified across many spatial scales (statewide to local) and two time periods in California and southern Oregon, USA. We also addressed (1) if old-growth forest fragmentation was negatively associated with murrelet use, and (2) if some nesting areas are more important than others due to their proximity to high quality marine habitat. Most landscapes used for nesting were restricted to low elevation areas with frequent fog. Birds were most abundant in unfragmented old-growth forests located within a matrix of mature second-growth forest. Murrelets were less likely to occupy old-growth habitat if it was isolated (> 5 km) from other nesting murrelets. We found a time lag in response to fragmentation, where at least a few years were required before birds abandoned fragmented forests. Compared to landscapes with little tono murrelet use, landscapes with many murrelets were closer to the ocean's bays, river mouths, sandy shores, submarine canyons, and marine waters with consistently high primary productivity. Within local landscapes (≤ 800ha), inland factors limited bird abundance, but at the broadest landscape scale studied (3200 ha), proximity to marine habitat was most limiting. Management should focus on protecting or creating large, contiguous old-growth forest stands, especially in low-elevation areas near productive marine habitat. This revised version was published online in July 2006 with corrections to the Cover Date.     

Role of cyclic nucleotides in the acute hypoxic responses of hypoxic subcultured porcine pulmonary arterial smooth muscle and endothelial cells

AIM: To detect the role of cyclic nucleotides in the alleviation of hypoxic pulmonary vasoconstriction (HPV) in chronic hypoxic animals. METHODS: The intracellular cAMP and cGMP of the cultured porcine pulmonary arterial smooth muscle cells (PASMC) and endothelial cells (PAEC) were assayed by RIA. The length of single PASMC during acute hypoxia was measured by imaging analysis system. RESULTS: The basal levels of cAMP and cGMP in PASMC and cGMP in PAEC of Chronic hypoxic groups decreased remarkably compared with normoxic groups (P＜0.01). Under acute hypoxia, the contents of cAMP and cGMP in PASMC of chronic hypoxic groups increased significantly (P＜0.01). Meanwhile, the percentage of PASMC with weak constrictive response in chronic hypoxic group was higher than that of control group. CONCLUSION:It's suggested that the changes of cAMP and cGMP in chronic hypoxic PASMC and PAEC might contribute to the increase in the basic tension of pulmonary artery and the alleviation of HPV in chronic hypoxic animals.