甜菜霜霉病的防效试验

对3种高效低毒的杀菌剂（72％锰锌·霜脲、50％烯酰·吗啉和69％锰锌·烯酰可湿性粉剂）与常规药剂50％多菌灵及清水处理应用于甜菜霜霉病进行防效试验,3种高效低毒的杀菌剂防治效果达90％以上,可延长甜菜功能叶片生命力,增产15.1％～31.5％,效果明显.     

10种杀菌剂对马铃薯晚疫病的防治效果与经济效益评价

选择72%霜脲·锰锌(克露)可湿性粉剂(WP)、50%烯酰吗啉(安克)WP、25%嘧菌酯(阿米西达)悬浮剂(SC)、64%恶霜·锰锌(杀毒矾)WP、68%精甲霜灵·锰锌(金雷)水分散粒剂(WG)、70%丙森锌(安泰生)WP、68.75%氟吡菌胺·霜霉威(银法利)SC、18.7%烯酰·吡唑酯(凯特)WG、25%双炔酰菌胺(瑞凡)SC和50%多菌灵WP等10种药剂进行了田间马铃薯晚疫病防治试验。结果表明:除50%多菌灵WP之外,其他9种药剂对马铃薯晚疫病均具有明显的防治效果和增产效果,防效均达90%以上,增产10.90%～20.30%,净收入增加500～1000元·(667m2)-1。根据药剂的防效和增产效果,提出广东省马铃薯晚疫病防治的参考药剂,首先是72%霜脲·锰锌WP和50%烯酰吗啉WP,其次是68%精甲霜灵·锰锌WG、18.7%烯酰·吡唑酯WG、25%嘧菌酯SC、70%丙森锌WP和64%恶霜·锰锌WP。     

几种杀菌剂防治葡萄霜霉病田间药效试验

选用4种药剂进行了防治葡萄霜霉病的田间药效试验。结果表明,78%科博、72%霜脲锰锌、80%烯酰吗啉、72.2%霜霉威都有防治效果,其中78%科博500倍液、80%烯酰吗啉2 500倍液的防效更高,药后10d防效均达92%以上。     

设施蔬菜苗期病害病原鉴定及化学药剂筛选

采用普查和定时系统调查的方法对十字花科(大白菜、青花菜、甘蓝、萝卜)、茄科(番茄、辣椒、茄子)、葫芦科(黄瓜、冬瓜、南瓜)等10种主要设施蔬菜苗期病害种类进行了调查,在此基础上采用形态学和分子生物学方法对病原进行鉴定,并对疫病、猝倒病、枯萎病、立枯病等4种主要苗期病害进行化学防治药剂筛选。结果表明:从10种蔬菜上采集的864份苗期病害病样中共分离出736株菌株,共计16个种,其中致病病原有13种,在各类蔬菜上可分别引起8~9种苗期病害,以传统病害猝倒病和立枯病为主,其次为根腐病、疫病、灰霉病;筛选出对立枯病防效显著的杀菌剂32.5%苯甲·嘧菌酯悬浮剂和2.5%咯菌腈悬浮剂,对防治枯萎病有效的药剂70%甲基托布津可湿性粉剂、36%甲基硫菌灵悬浮剂和3%甲霜·噁霉灵水剂,对疫病防效显著的药剂68%精甲霜·锰锌水分散粒剂、25%甲霜·霜霉威可湿性粉剂、72%霜脲·锰锌可湿性粉剂、50%烯酰吗啉水分散粒剂、50%氟啶胺悬浮剂、64%噁霜·锰锌可湿性粉剂、10%氰霜唑悬浮剂,以及防治猝倒病有效的药剂50%氟啶胺悬浮剂、64%噁霜·锰锌可湿性粉剂、10%氰霜唑悬浮剂、72%霜脲·锰锌可湿性粉剂、72.2%霜霉威盐酸盐水剂、50%烯酰吗啉水分散粒剂、68%精甲霜·锰锌水分散粒剂和60%唑醚·代森联水分散粒剂等。     

55%福美双·烯酰吗啉可湿性粉剂防治黄瓜霜霉病田间药效试验

以50%福美双可湿性粉剂120g/667m2和50%烯酰吗啉可湿性粉剂40g/667m2为对照药剂,试验观察了55%福美双·烯酰吗啉可湿性粉剂40g/667m^2,100g/667m^2,160g/667m23个剂量处理对黄瓜霜霉病的田间防效。试验结果表明,施药后10d,防效分别为62.35%,70.26%,74.19%,以55%福美双·烯酰吗啉可湿性粉剂160g/667m^2处理防效最高,且对黄瓜安全。     

阳光玫瑰葡萄霜霉病田间药效防治试验

对6年生阳光玫瑰葡萄的霜霉病,采用了8种药剂进行了2022—2023年2年的田间防治效果试验,于每年7月霜霉病开始发生时进行喷药,按照药剂生产厂家推荐的喷施浓度间隔10 d喷1次,共喷3次,以喷清水为对照。结果表明,供试的8种药对葡萄霜霉病均有一定的防治效果且对植株安全无药害。其中2种药剂60%霜脲·嘧菌酯水分散粒剂1 500倍液、31%噁酮·氟噻唑悬浮剂1 500倍液防效突出,2年防效稳定在90%以上,为理想选择药剂;4种药剂40%克菌·戊唑醇悬浮剂1 000倍液、40%烯酰·氰霜唑悬浮剂2 000倍液、22.5%啶氧菌酯悬浮剂1 500倍液、50%烯酰吗啉可湿性粉剂1 500倍液防效均在80%以上,为可选用药剂;另2种药剂58%甲霜·锰锌可湿性粉剂500倍液、75%百菌清可湿性粉剂500倍液防效不够理想,不宜用于防治葡萄霜霉病。     

莴笋霜霉病防治药剂田间筛选试验

为筛选出防治莴笋霜霉病的有效药剂,为大田生产推广应用提供可靠依据,开展了7种杀菌剂田间药效比较试验。试验结果表明,80%烯酰吗啉可湿性粉剂和68%精甲霜·锰锌水分散粒剂对莴笋霜霉病防效较好,田间防治效果明显,可在生产上选择使用。     

辣椒疫病药剂防治效果及对产量和农艺性状的影响

为筛选出防治辣椒疫病的高效低毒新药剂,以遵辣6号为供试品种,选择68.75%银法利、58%甲霜灵猛锌、69%烯酰吗啉·锰锌、72%霜霉疫净及70%安泰生5种药剂进行防效试验,并对施药后辣椒的农艺性状和产量进行调查。结果表明,68.75%银法利、58%甲霜灵锰锌、69%烯酰吗啉·锰锌、72%霜霉疫净及70%安泰生对辣椒疫病的防治效果分别为80.12%、73.2%、59.84%、40.05%和19.88%,用药后辣椒产量分别比对照增产18.39%、15.33%、13.8%、8.05%和6.51%。这5种药剂的综合表现依次为68.75%银法利58%甲霜灵锰锌69%烯酰吗啉·锰锌72%霜霉疫净70%安泰生。     

银法利等杀菌剂防治葡萄霜霉病试验研究

试验表明,银法利687.5 g/L悬浮剂、赛凡嗯霜·猛锌可湿性扮剂、霉敌烯酰·丙森锌可湿性粉剂均为防治葡萄霜霉病的良好药剂,防效显著,而且持效期较长;瑞毒霉可湿性粉剂的防效最快,最为明显,但是持效期较短;70%甲基托布津的防效较差.     

不同组合药剂对马铃薯晚疫病的防治效果

马铃薯晚疫病是一种毁灭性病害,会严重降低马铃薯的产量和品质。为提高马铃薯晚疫病的防治效果,作者以甘肃省徽县马铃薯主栽品种费乌瑞它为试验材料,开展了不同组合药剂对马铃薯晚疫病的防治效果试验。试验结果表明,“72%甲霜·锰锌可湿性粉剂1.5 kg/hm^(2)+68.75%氟吡菌胺·霜霉威悬浮剂1 L/hm^(2)”处理马铃薯晚疫病的防效最好(92.18%)、产量最高(39 400 kg/hm^(2))、商品薯率最高(85.4%);其次为“72%霜脲·锰锌可湿性粉剂1.2 kg/hm^(2)+68.75%氟吡菌胺·霜霉威1 L/hm^(2)”处理,马铃薯晚疫病的防效为90.13%,产量为38 500 kg/hm^(2),商品薯率为83.2%。上述两种药剂组合可用于防治马铃薯晚疫病,建议在马铃薯生产上推广应用。     

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.     

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.     

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.     

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.