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1.
白菜与甜菜间作的生长与资源利用效果   总被引:1,自引:0,他引:1  
通过设置不同的白菜与甜菜间作密度,监测了复合群体的叶面积指数、漏光率以及各作物产量,研究复合群体的生长动态,光资源分布以及产量产值效应。结果表明:在间作群体中,白菜依其速生优势而表现偏利效应,间作甜菜前期受白菜遮蔽胁迫,其生育期叶面积指数始终低于单作;白菜收获后甜菜通过叶层自动空间散布提高光能截获率,促进了后期光合补偿性生产;白菜2行∶甜菜1行间作(BT1)处理,白菜的实际产量比"预期"产量极显著增高26.7个百分点,甜菜比"预期"产量增高34.0个百分点;白菜2行∶甜菜2行间作(BT2)处理,白菜、甜菜的实际产量比"预期"产量分别极显著增高59.3、53.0个百分点;BT1、BT2间作群体较白菜单作经济效益分别提高10.2、23.7个百分点,较甜菜单作经济效益分别提高91.5、115.1个百分点。分析表明,间作种植显著提高了地气资源的利用效率,BT1间作LER为1.29;BT2间作LER高达1.56。  相似文献   

2.
为综合评价河北省太行山地区苹果园土壤肥力与施肥现状,通过实地调查该地苹果园不同养分投入量、投入类型以及各养分在0~60 cm土层分布状况,并进一步采用产量差法探究最佳养分投入量。结果表明,河北省太行山地区苹果园有机肥平均施入量为5934.72 kg/hm^2,以鸡粪、羊粪、牛粪为主;无机肥N、P2O5、K2O投入量分别为777.63 kg/hm^2、421.86 kg/hm^2、543.39 kg/hm^2。土壤养分随土层加深呈降低趋势,其中0~20 cm土层有机质、有效磷、速效钾、有效铁含量均达到了丰富水平,但有效锰含量处于较低水平,有效铜、有效锌处于适量水平。产量差模型分析显示,河北省太行山苹果园最高产量N、P2O5、K2O投入量分别为821.87 kg/hm^2、580.73 kg/hm^2、676.99 kg/hm^2。建议在实际生产中应降低氮、钾肥投入,适当补充磷、锰肥,同时搭配有机肥。  相似文献   

3.
以紫菀为试材,采用HPLC法,研究磷肥的不同施肥量(35、40、45kg/667m2)对紫菀的产量、有效成分(紫菀酮)含量的影响。结果表明:当磷肥施用量为40kg/667m2时,其对紫菀的农艺性状及有效成分含量影响显著;当施用量为45kg/667m2时,紫菀产量最高,但与40kg/667m2不存在显著差异,因此确定40kg/667m2为紫菀磷肥的最佳施用量。  相似文献   

4.
以半夏、魔芋、大豆及辣椒为试材,采用随机区组设计大田试验,研究单作半夏及半夏间作魔芋(半夏‖魔芋)、半夏间作辣椒(半夏‖辣椒)、半夏间作大豆(半夏‖大豆)3种间作处理对半夏产量及品质的影响。结果表明:在产量方面,与大豆间作半夏总产量最高,与辣椒间作半夏一级种产量最高,一级种与四级种呈此消彼长的态势,再加之变异系数较大,所以通过间作提高半夏一级种产出是提高半夏产量的有效途径;在品质方面,与魔芋间作半夏的可溶性蛋白质及浸出物含量最高,与辣椒间作半夏的可溶性糖、还原糖、琥珀酸及鸟苷含量最高,与大豆间作半夏的生物碱含量最高,但品质方面变异系数较小。通过主成分对产量及品质分析综合评分得出半夏‖大豆最高,半夏‖辣椒次之,可作为半夏高产优质栽培的理想间作搭配,为半夏产业化种植提供重要的理论依据。  相似文献   

5.
为了研究不同配比的磷钾肥对1 a生、2 a生有效成分含量的影响,采用田间试验测定1 a生、2 a生防风根干重,以HPLC测定防风有效成分升麻素苷和5-O-甲基维斯阿米醇苷的含量。结果表明,当1 a生和2 a生防风施肥处理分别为P2O5124 kg/hm2和K2O 46 kg/hm2、P2O5186 kg/hm2和K2O 92 kg/hm2时,防风根干重均达到最大值。当1 a生、2 a生防风分别施用P2O5124 kg/hm2和K2O 46 kg/hm2、P2O5124 kg/hm2和K2O 92 kg/hm2时,防风中升麻素苷和5-O-甲基维斯阿米醇苷总含量最高。钾肥对1 a生、2 a生防风根干重均有显著影响。最适于防风有效成分积累的磷肥量为P2O5124 kg/hm2。一定范围内配合施用磷钾肥促进防风生长,有利于升麻素苷和5-O-甲基维斯阿米醇苷含量积累。综合考虑产量与品质,在田间氮素补至一致条件下,即每公顷含氮量为72 kg时,1 a生、2 a生防风肥料施用量分别为P2O5124 kg/hm2和K2O 46 kg/hm2、P2O5124 kg/hm2和K2O 92 kg/hm2,可获得成本低、优质高产防风,对于农业生产实践具有指导意义。  相似文献   

6.
以马铃薯‘荷兰15’一级种为试验种植材料,探讨马铃薯‘荷兰15’磷肥4种施用量的鲜薯产量、商品薯产量与经济效益。结果表明,适当增加磷肥(P2O5)施用量,可以提高出苗率,增加鲜薯产量、商品薯产量与经济效益。磷肥(P2O5)施用量8 kg/667 m2的鲜薯产量、商品薯产量最高,每667 m2分别为2 513.3 kg和2 254.5 kg,极显著高于不施磷肥鲜薯产量与商品薯产量,显著高于磷肥(P2O5)施用量12 kg/667 m2的鲜薯产量与商品薯产量。磷肥(P2O5)施用量8 kg/667 m2的经济效益最高,为2 965.9元,比不施磷、磷肥(P2O5)施用量4、12 kg/667 m2分别增效1 175.4、805.3和646.4元。综合考虑,承德中南部区域种植马铃薯‘荷兰15’,磷肥(P2O5)施用量8 kg/667 m2最适宜。此水平磷肥(P2O5)施用量的鲜薯产量、商品薯产量及经济效益均最高。  相似文献   

7.
董敏 《上海蔬菜》2023,(4):41-43
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。  相似文献   

8.
利用“3414”试验设计,开展福安市巨峰葡萄氮磷钾肥效田间试验,结果表明:施用氮磷钾肥分别增产33.9%、28.0%和31.1%.在试验条件下,每667 m2最高产量施肥量为N 16.95 kg,N∶P2O5∶K2O =1∶0.78∶1.22,最高产量为1 476.7 kg;每667 m2最佳经济施肥量为N 16.08 kg,N∶P2O5∶K2O=1∶0.78∶1.23,经济产量为1 475.4 kg.  相似文献   

9.
生姜的营养特性及钾对生姜产量和土壤肥力的影响   总被引:2,自引:0,他引:2  
以安丘生姜为试材,研究了生姜不同生长期的养分吸收特性,以及不同钾水平对生姜产量和土壤肥力的影响。结果表明:姜对钾素的需求最多,每生产1 000 kg姜需要从土壤中吸收6.1 kg N、2.36 kg P2O5、9.4 kg K2O。K3处理〔K2O 70 kg?(667 m2)-1〕的生姜产量最高,但与K2处理〔K2O 50 kg?(667 m2)-1〕之间差异不显著。通过产量和施肥量的拟合曲线获得最高产量的钾肥施用量为60 kg?(667 m2)-1,综合考虑不同钾水平对生姜养分吸收和土壤肥力的影响,得出本试验条件下生姜周年生产的钾肥(K2O)投入量为667 m2 50~60 kg比较适宜,同时适宜的氮钾比例为4∶5~4∶6。  相似文献   

10.
菜豆新品种连农无筋2号的选育   总被引:1,自引:0,他引:1  
连农无筋2号利用杂交育种,后代经过系统选育而成。它涉及4个亲本:82-3长菜豆、85-1、Cornell49-242、87B。植株蔓生 ,商品荚绿色,扁形,荚长22 cm,荚宽1.5~2.0 cm,荚厚1.2~1.7 cm,荚形指数1.36,单荚质量23.0 g左右。抗锈病,中抗炭疽病 。春、秋露地栽培每667 m2产量分别为3 076、2 243 kg,春季大棚栽培平均每667 m2产量2 500 kg左右,冬季温室栽培平均产量3 200 kg,适合北方地区春秋大棚、春秋露地及冬季温室栽培。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
多效唑对猕猴桃离体试管苗生长及内源激素的影响   总被引:18,自引:0,他引:18  
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。  相似文献   

18.
AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.  相似文献   

19.
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.  相似文献   

20.
AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [3-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10-6-10-4 mmol/L) stimulated [3-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [3-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P<0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P<0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10-6-10-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P<0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl2 for 6 h induced an increase cellular MT content by 5.7-fold (P<0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P<0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.  相似文献   

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