覆砂对库尔勒香梨园土壤保水性和产量的影响

以22年树龄的库尔勒香梨园土壤为研究对象,进行表层覆砂试验,设置不同覆砂厚度,采用常规方法监测土壤灌水后不同时间点上的土壤含水量以及库尔勒香梨产量,分析覆砂厚度对香梨园不同时期土壤含水量和果树产量的影响。结果表明:覆砂能抑制土壤蒸发,提高土壤含水量,促进果树增产。土壤覆砂5cm处理对提高土壤保水性效果较好,但与覆砂2cm处理土壤含水量相比无显著差异。覆砂2cm处理和覆砂5cm处理的库尔勒香梨产量较不覆砂处理库尔勒香梨产量增加8.81%和11.05%。综合考虑覆砂对库尔勒香梨园土壤保水性、果实增产和改善果形特征的影响,该研究推荐库尔勒香梨园表土覆砂以2cm厚度为最佳。     

深松对干旱灌区土壤物理性质与玉米产量的影响

通过对土壤容重、土壤含水量、土壤田间持水量及产量的分析对比,研究深松40 cm对土壤耕层的物理性质及对玉米产量的影响。结果表明,在0~10 cm深松与对照土壤容重差异不显著,土壤含水量和田间持水量差异达到极显著水平;而在10~40 cm深松与对照的土壤容重、含水量、田间持水量均达到极显著差异水平,玉米产量比对照增产8.0%。     

EM微生物菌剂不同施用方法对大棚辣椒产量和品质的影响

研究了EM微生物菌剂不同施用方法对大棚辣椒产量、营养品质和安全品质的影响。研究结果表明,EM微生物菌剂不同施用方法对辣椒生长与结果的影响效果差异显著,以EM微生物菌剂发酵处理有机肥的施用方法增产效果最显著,辣椒VC、氨基酸含量明显提高,硝酸盐含量降低,分别比EM微生物菌剂土壤灌施、叶面喷施和不施用EM微生物菌剂增产19.44%、44.05%和71.14%;其次是EM微生物菌剂土壤灌施,分别比叶面喷施和不施用EM微生物菌剂增产9.07%和20.60%;叶面喷施效果不明显。     

旱地果园高垄覆黑膜集雨沟保墒试验初报

2011年对旱地果园采取高垄覆盖黑膜集雨沟保墒试验,并对土壤含水量进行测定。结果表明,采用起高垄覆盖黑膜集雨沟保墒模式明显优于单纯起高垄覆盖黑膜保墒模式,显著地增加了旱塬区果园土壤含水量,为增产增效创造了条件,应进一步示范推广。     

马铃薯不同覆盖方式抗旱增产效果对比试验

甘肃旱作马铃薯种植区干旱少雨,导致马铃薯产量低而不稳,种植效益低下。为筛选出适宜的集雨保墒技术,实施了不同覆盖方式抗旱增产试验。结果表明：全膜垄作微沟栽培平均亩产2 366.4 kg,比露地栽培增产394 kg,增幅20%,水分利用效率为7.1 kg/mm·亩;秸秆覆盖垄作栽培平均亩产2 315.4 kg,比露地栽培增产343 kg,增幅17.4%,水分利用效率为6.2 kg/mm·亩。     

不同水分用量对小香葱生长的影响

为探明小香葱生长对水分的需求规律,采用盆栽法研究不同水分处理对小香葱生长的影响。结果表明,水分对小香葱的部分性状及产量影响显著,随着浇水量的增加,株高、株幅、假茎横径、单株叶数、分蘖数、根数、根长、地上部鲜重及地下部鲜重均逐渐增加而后下降,以1kg烘干土壤每次浇水700 m L的小香葱生长势较好,产量最高,较其他处理增产92.92%～537.43%,折合土壤含水量为70%时,增产效果显著。     

木薯加工废弃物转化有机肥料在辣椒栽培上的施用效果

研究不同施肥处理对辣椒农艺性状、品质、产量和土壤理化性状的影响,明确和完善有机肥ZH-2在辣椒上的施用效果,同时为辣椒优质高产栽培技术提供理论依据。以辣椒作为研究对象,施以不同肥料处理,分别测定辣椒农艺性状、品质、产量及土壤理化性状。施有机肥ZH-2后,除根长与不施肥处理之间的差异达到显著水平外,辣椒植株其他农艺性状和果实农艺性状指标都极显著高于对照。其中一级侧根数与椒肉厚两指标最高,同施国产无机复混肥之间的差异均达到显著水平,较各处理可分别提高10.00%～57.14%和1.38%～27.75%,其他农艺性状与两个施肥处理间未存在显著性差异。同时其叶绿素b含量与叶绿素总量最高,叶色为深绿色;还原糖与维生素C含量较其他施肥处理提高2.27%～38.46%、5.72%～21.27%;产量指标极显著高于对照,与两个施肥处理之间的差异不显著,单株产量、小区总产量比对照分别增产133.33%、131.49%。此外,施有机肥ZH-2后,土壤的理化性状也得到改善,土壤含水量、总孔度最大,容重、水气比最小,同时土壤团聚体含量、土壤有机质、全N、全K含量均为最高。有机肥ZH-2在提高辣椒品质和产量的同时,也兼具极佳的改土培肥效果,是一种值得在辣椒栽培上推广应用的新型肥料。     

木薯加工废弃物转化有机肥料在辣椒栽培上的施用效果简

研究不同施肥处理对辣椒农艺性状、品质、产量和土壤理化性状的影响，明确和完善有机肥ZH-2在辣椒上的施用效果，同时为辣椒优质高产栽培技术提供理论依据。以辣椒作为研究对象，施以不同肥料处理，分别测定辣椒农艺性状、品质、产量及土壤理化性状。施有机肥ZH-2后，除根长与不施肥处理之间的差异达到显著水平外，辣椒植株其他农艺性状和果实农艺性状指标都极显著高于对照。其中一级侧根数与椒肉厚两指标最高，同施国产无机复混肥之间的差异均达到显著水平，较各处理可分别提高10.00%～57.14%和1.38%～27.75%，其他农艺性状与两个施肥处理间未存在显著性差异。同时其叶绿素b含量与叶绿素总量最高，叶色为深绿色；还原糖与维生素C含量较其他施肥处理提高2.27%～38.46%、5.72%～21.27%；产量指标极显著高于对照，与两个施肥处理之间的差异不显著，单株产量、小区总产量比对照分别增产133.33%、131.49%。此外，施有机肥ZH-2后，土壤的理化性状也得到改善，土壤含水量、总孔度最大，容重、水气比最小，同时土壤团聚体含量、土壤有机质、全N、全K含量均为最高。有机肥ZH-2在提高辣椒品质和产量的同时，也兼具极佳的改土培肥效果，是一种值得在辣椒栽培上推广应用的新型肥料。     

黄河冲积土苹果园土壤生产性能分析

通过田间调查,从土壤性质、苹果根系生长特点、地上部生长情况、果实产量和品质等方面对黄河冲积土苹果园土壤生产性能进行了初步的分析。结果表明,土壤质地和层次结构的差异,造成了土壤水分含量的不同,而雨季过高的土壤含水量会使土壤空气含量下降,从而使根系吸收功能降低,这是导致树体旺长、果实产量和质量较低的一个重要原因。无障碍层次的壤土和砂土较适于果树生产。     

土壤环境调控对板栗细根形态和产量的影响

【目的】为解决河北迁西地区板栗园干旱缺水和不合理施肥导致的土壤肥力下降等问题,依据当地实际情况提出一个优化的土壤管理模式,并进行效果验证,为其改进和推广提供理论依据。【方法】以8年生板栗燕山早丰(Castanea mollissima‘Yanshanzaofeng’)为研究对象,采用裂区试验设计,主处理为行间覆草(GC)和清耕(CT),副处理为4个施肥处理,即无机肥(F)、有机肥(M)、有机肥和无机肥配施(F+M)、不施肥(CK),于2019和2020年连续2 a(年)研究覆草-施肥模式对板栗园土壤状况和细根形态以及单株产量的影响。【结果】行间覆草处理的土壤平均含水量显著高于清耕处理,覆草区0～20 cm和20～40 cm土层平均含水量分别比清耕区相应土层高18.76%、17.62%;而且行间覆草还具有高温时节降温、低温时节保温的作用;各施肥处理均能降低0～40 cm土层的土壤容重,增加总孔隙度。覆草和施肥处理可显著提高板栗园根际土壤有机质和速效养分含量,对板栗细根养分含量和形态特征也产生了显著的影响,而且各指标均表现为GCCT,其中GC(F+M)和CT(F+M)处理的增量最为显著;GC(F+M)处理的单株产量最高,不同覆草-施肥模式增产幅度为4.95%～45.21%。聚合增强树分析表明,不同土壤理化指标对板栗单株产量的贡献程度由大到小依次为ANAKAPSWCTEMOMpHTPSBD,土壤速效养分和含水量对单株产量的贡献率最高,分别为52.21%、13.91%。【结论】在迁西地区板栗栽培中,行间覆草结合有机肥和无机肥配施是该地区板栗增产的较适宜的土壤管理方式,建议广泛推广。     

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.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。