工厂化栽培杏鲍菇优良菌株筛选试验

试验比较了11个杏鲍菇菌株菌丝生长速率、拮抗情况、栽培周期、总产量、生物学效率、子实体栽培性状等。结果表明:农大杏北菌株栽培周期短,产量高,子实体性状优良,适合工厂化栽培;杏528菌株子实体栽培性状与其他菌株有显著差异,但其生长周期最短,可以作为杏鲍菇杂交育种的亲本。     

不同杏鲍菇品种种质鉴定及原生质体单核体杂交育种

以7个生产上常用的杏鲍菇菌株为试材，采用拮抗试验、酯酶同工酶技术、ISSR分子标记技术对不同杏鲍菇菌株进行鉴别分类；进而利用原生质体单核体杂交育种技术，将不同种类、不同交配型菌株进行单单杂交，筛选出杂交成功且具有锁状联合的杂交菌株，对比杂交菌株与亲本菌株的菌丝生长速率、农艺性状等，以期为杏鲍菇的实际生产与栽培提供优良种质资源。结果表明：拮抗反应、酯酶同工酶、ISSR的研究结果一致，将7个杏鲍菇菌株分为3类，第1类为12、16、1208、1219、1287菌株；第2类为1283菌株；第3类为1284菌株。通过原生质体单核体杂交技术，获得24个杂交菌株；与亲本对比，筛选出了5个菌丝生长速率、菇体质量显著优于亲本的菌株，分别为ZJ5、ZJ8、ZJ11、ZJ17、ZJ22菌株。     

杏鲍菇13号杂交菌株选育研究

用杏鲍菇1号菌株和9号菌株通过单孢杂交育种方法选育出杏鲍菇13号杂交菌株。杏鲍菇13号杂交菌株的子实体产量最高,生物学效率达到109．20％。 ?A ?A ?A ?A ?A     

灰色关联度法在杏鲍菇优良杂交菌株筛选中的应用

以杏鲍菇(Pleurotus eryngii ) 6号和ACCC50894为亲本,分别采用单孢杂交和原生质体单核体杂交方式获得65和37个杂交子,观测杂交子及亲本菌丝体生长情况,选择长势好及生长快速的杂交子进行栽培出菇试验.采用灰色关联度分析法对15个生长势较强的杂交子从7个性状方面进行综合评价,结果表明,单孢杂交获得的杂交子D12、D18、D20、D30、D19、D31、D17和D48关联度排名先于两亲本,农艺性状和子实体性状表现较好;原生质体单核体杂交菌株Y29和Y30关联度排名介于两亲本之间.     

16个杏鲍菇菌株的生物学特性及亲缘关系研究

对16个不同杏鲍菇菌株的菌丝拮抗作用、菌丝生长特性、生物学效率及子实体性状特征进行比较研究。研究结果表明,杏鲍菇栽培品种比较混乱,同种异名、同名异种的现象较为严重,同种异名的菌株间生物学特性表现出显著差异。杏01(杏鲍菇-1)、杏13(杏F)两个菌株的菌丝生长较快,长势较好,菌丝浓密,原基分化快,栽培周期短;出菇产量高,生物学效率均大于70%;菌盖大小适中,菌柄长且粗壮,子实体个体大,单菇重量大,组织致密,子实体各项性状优良。因此,菌株杏01与杏13可作为杏鲍菇优良菌株进行示范推广。     

甘蔗渣栽培杏鲍菇的配方比较试验

利用漳州地区大量低价、营养丰富的甘蔗渣工厂化栽培杏鲍菇,筛选以甘蔗渣为主料栽培杏鲍菇培养料配方。结果以配方3(甘蔗渣55%,木屑20%,玉米芯10%,麸皮10%,玉米粉3%,轻质碳酸钙1%,石灰1%)栽培杏鲍菇的效果最好,能够较好的促进菌丝生长,保持优良的生长性状,提高杏鲍菇多糖含量,杏鲍菇子实体产量和生物学转化率最高,且配方3的经济效益明显高于传统配方(CK)。     

白背毛木耳杂交育种及杂交子选育

为了获得性状优良的毛木耳新品种,进行了杂交育种。实验以钩悬法收集毛木耳"丰2"子实体单孢子并培养获得其单核菌丝。采用单孢杂交(两点法)进行杂交培养,镜检"锁状联合"初选杂交子;通过与亲本的拮抗实验和酯酶同工酶电泳酶谱比对分析确认杂交子,并经出耳试验验证其结实性。实验结果显示,种内杂交的不同单核菌丝较易亲和并产生具结实能力的杂交子。     

杏鲍菇14号杂交菌株选育研究

用杏鲍菇9号菌株和11号菌株通过单孢杂交育种技术选育出杏鲍菇14号杂交新茵株。杏鲍菇14号杂交新菌株的子实体呈棍棒形，生物学效率达到84．64％。     

杏鲍菇16号杂交菌株选育

用杏鲍菇10号菌株和13号菌株通过单孢杂交育种技术选育出杏鲍菇16号杂交新菌株。杏鲍菇16号杂交新菌株的子实体呈保龄球形，产量较高，生物学效率达到118．33％。     

酯酶同工酶技术在杏鲍菇杂种优势预测中的应用研究

探讨酯酶同工酶技术在杏鲍菇杂种优势预测中的应用.采用垂直平板聚丙烯酰胺凝胶电泳技术,以单孢杂交筛选的14个杏鲍菇杂交子代及其7个亲本为材料,对菌株间的亲缘关系和遗传差异进行了分析比较,预测杂交子代杂种优势的强弱.在一定范围内,杂交亲本的相似系数越小,也就是亲缘关系越远,杂交优势就越明显.试验根据杏鲍菇杂交子代酯酶同工酶酶谱“互补型酶带”和“杂种新酶带”的多少预测杏鲍菇杂交菌株强优势组合,杂交后代出现强优势的杂交子代有5-528、C-5、5X-511、5X-7菌株.酯酶同工酶分析技术在杂交育种、降低工作量、减少成本等方面具有指导意义.     

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.     

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.     

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.     

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.     

Mixed-severity fire regime in a high-elevation forest of Grand Canyon,Arizona, USA

Fire regime characteristics of high-elevation forests on the North Rim of the Grand Canyon, Arizona, were reconstructed from fire scar analysis, remote sensing, tree age, and forest structure measurements, a first attempt at detailed reconstruction of the transition from surface to stand-replacing fire patterns in the Southwest. Tree densities and fire-/non-fire-initiated groups were highly mixed over the landscape, so distinct fire-created stands could not be delineated from satellite imagery or the oldest available aerial photos. Surface fires were common from 1700 to 1879 in the 4,400 ha site, especially on S and W aspects. Fire dates frequently coincided with fire dates measured at study sites at lower elevation, suggesting that pre-1880 fire sizes may have been very large. Large fires, those scarring 25% or more of the sample trees, were relatively infrequent, averaging 31 years between burns. Four of the five major regional fire years occurred in the 1700s, followed by a 94-year gap until 1879. Fires typically occurred in significantly dry years (Palmer Drought Stress Index), with severe drought in major regional fire years. Currently the forest is predominantly spruce-fir, mixed conifer, and aspen. In contrast, dendroecological reconstruction of past forest structure showed that the forest in 1880 was very open, corresponding closely with historical (1910) accounts of severe fires leaving partially denuded landscapes. Age structure and species composition were used to classify sampling points into fire-initiated and non-fire-initiated groups. Tree groups on nearly 60% of the plots were fire-initiated; the oldest such groups appeared to have originated after severe fires in 1782 or 1785. In 1880, all fire-initiated groups were less than 100 years old and nearly 25% of the groups were less than 20 years old. Non-fire-initiated groups were significantly older (oldest 262 years in 1880), dominated by ponderosa pine, Douglas-fir, or white fir, and occurred preferentially on S and W slopes. The mixed-severity fire regime, transitioning from lower-elevation surface fires to mixed surface and stand-replacing fire at higher elevations, appeared not to have been stable over the temporal and spatial scales of this study. Information about historical fire regime and forest structure is valuable for managers but the information is probably less specific and stable for high-elevation forests than for low-elevation ponderosa pine forests.This revised version was published online in May 2005 with corrections to the Cover Date.     

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.     

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.     

瓜叶绿素降解关键酶基因PPH和PAO cDNA片段的克隆与表达初步分析

 以西双版纳黄瓜和‘华黄5号’黄瓜叶片为试验材料,研究了衰老过程中两种黄瓜叶片叶绿素含量变化及脱镁叶绿素脱镁叶绿酸水解酶基因PPH和脱镁叶绿酸a加氧酶基因PAO的表达。结果表明：随着叶片衰老,叶绿素a和叶绿素b含量显著降低,叶绿素a与叶绿素b的比值在0.5左右,推测叶绿素b的含量可能对黄瓜叶片保绿起到重要作用。荧光定量RT-PCR分析结果显示：PPH和PAO在西双版纳黄瓜叶片生长35 d时表达量最高,分别为5.50和1.86;PPH在‘华黄5号’叶片35 d时表达量最高,为7.14,而PAO在35和45 d表达量都很高,分别为3.90和3.91;PPH和PAO在西双版纳黄瓜叶片中的表达量低于在‘华黄5号’中。     

Effects of simvastatin on PDGF-BB and serum-induced proliferation of vascular smooth muscle cells and on the expression of tumor suppressor gene PTEN

AIM:To observe the effect of simvastatin on the proliferation of vascular smooth muscle cells(VSMCs) induced by serum and growth factor PDGF-BB and the effect of simvastatin on the expression of PTEN,a important regulator of G₁/S cell cycle transition. METHODS:The DNA synthesis was determined by [³H]-TdR incorporation, cell cycle was examined with flow cytometry, the protein level of PTEN was measured by Western blot method. RESULTS: (1)Simvastatin inhibited [³H]-TdR incorporation in a dose dependent manner. (2) Flow cytometric DNA analysis revealed that simvastatin induced significantly enhancement of G₀/G₁ phase and decrease in S phase VSMCs.(3)Simvastatin increased protein level of PTEN and mevalonate, a metabolite of HMG-COA, reversed the effect of simvastatin on PTEN protein expression. CONCLUSION:Simvastatin may inhibit proliferation of VSMCs and retarded cell cycle in G₀/G₁ phase by increasing PTEN expression through inhibiting synthesis of mevalonate.     

Relationships of landscape,prey and agronomic variables to the abundance of generalist predators in cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis>) fields

A two-year field study investigated the possible effects of grain sorghum (Sorghum bicolor [L.] Moench) and uncultivated areas on the abundance of generalist predators in commercially-managed cotton (Gossypium hirsutum L.) fields in Texas, USA. From 63 to 70 fields were sampled for pests and predators over nine consecutive weeks during early stages of cotton development. Additional data on agronomic practices and landscape composition at three spatial scales were also collected for each field. Stepwise regression analyses were used to determine the relationships of landscape, agronomic and prey variables to the abundance of generalist predators. Because the variables most closely linked to predator levels could vary over time, separate regressions were conducted for three time periods corresponding to stages of grain sorghum growth (half-bloom, hard-dough, maturity) in each year. Significant relationships between predator abundance and agricultural landscape composition appear in both years and in all three time periods, but the specific relationships of landscape variables to cotton predator levels differed between and within years. At maturity in 2001, predator levels rose as the amount of uncultivated land from 1.6 to 3.2 km distant and the perimeter shared with grain sorghum increased. During 2002, the area of grain sorghum (half-bloom) and uncultivated land (hard-dough) within 1.6 km of cotton fields were both positively related to predator numbers. Cotton planting dates and the abundance of cotton fleahoppers (Pseudatomoscelis seriatus [Reuter]) were also strongly linked to predator numbers during both years. Results suggest that the total amount of grain sorghum or uncultivated land in an area is more important than the presence of these habitats adjacent to cotton fields, and that landscape composition may sometimes be the most important factor in determining predator abundance.