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1.
本文研究了GA3逆转高浓度乙烯利抑制黄瓜幼苗生长的效应。GA35×10-6、10×10-6、20×10-6均能有效解除乙烯利对黄瓜幼苗生长产生的抑制作用,使受乙烯利胁迫的黄瓜幼苗外部形态和生长量接近于正常水平。  相似文献   

2.
乙烯利是一种微效生长抑制剂,用500ppm处理黄瓜幼苗,使其茎的伸长,茎粗的增加和叶面积的扩展均受到严重抑制,茎叶,根干鲜重明显小于对照,经过乙烯利处理的黄瓜幼苗趋向于老化苗,用赤霉素喷叶处理老化苗,有效地逆转了乙烯利对幼苗形态的影响,使逆转苗更趋向于壮菌指标,在赤霉素的三种浓度中,10ppm的处理效果最好。  相似文献   

3.
龙眼授粉生物学研究   总被引:19,自引:0,他引:19  
龙眼花粉萌发的适温为20 ̄30℃,添加2,4-D10×10^-6 ̄20×10^-6、GA315×10^-6 ̄30×10^-6、NAA20×10^-6 ̄40×10^-6,三十烷醇2×10^-6 ̄3×10^-6以及硼砂50×10^-6 ̄200×10^-6、钼酸铵1×10^-4 ̄5×10^-6,均可显著提高其花粉育性。龙眼授粉的有效时间为开花后1 ̄4天,以开花后2天内授粉着果率最高;授粉后5小时已有少量  相似文献   

4.
几种植物生长调节剂对葡萄果实大小品质的效应   总被引:3,自引:1,他引:2  
对CPPU、GA3PDJ和S-ABA等几中植物生长调节剂组合对葡萄果实大小和品质的影响进行了研究,结果表明:在盛花期前10天GA350×10^-6配合盛花后10天CPPU10×10^-6和GA310×10^-6混合处理,增大白香蕉葡萄果穗和果粒重量的效果明显,同时增加了果实可溶性固形物含量和着色度。在盛花后15天CPPU5×10^-6配合果实着色始期PDJ250×10^-6的处理,可明显增大藤稔葡  相似文献   

5.
无核枇杷生产技术研究   总被引:13,自引:0,他引:13  
用250×10^-6,500×10^-6和1000×10^-6GA对“霸红”枇杷花穗进行喷雾均可诱导无核果实,花前处理效果好于其他时间处理。对GA诱导的无核枇杷幼果用CPPU+GA处理可促进其膨大并减少脱落,多次使用效果更好。花后每月一次用30×10^-6CPPU+500×10^-6GA喷雾4次获得了商品果大小的无核枇杷。  相似文献   

6.
乙烯利浸种对生姜增产效应的研究   总被引:4,自引:0,他引:4  
本试验以不同浓度的乙烯利处理种姜,研究乙烯利对生姜发芽、植株生长的影响及增产效应,结果表明:250×10-6~500×10-6为生姜浸种的适宜浓度,具有促进发芽、增加分枝、扩大叶面积和提高根茎产量的作用,一般比对照增产20%以上。  相似文献   

7.
PP333对柠檬成花,花量及花质的影响   总被引:2,自引:0,他引:2  
在四川重庆于10月23日和11月3日对8年生枳砧尤力克柠檬用300×10^-6,450×10^-6PP333进行叶面喷施,可极显著或显著地促进成花,提高花量和正常花的比例,对次年着果也有良好效果。  相似文献   

8.
乙烯利处理对黄瓜叶片生理活性及品质的影响   总被引:2,自引:0,他引:2  
关于乙烯利在黄瓜上的应用研究,前人往往局限于调查雌花数多少、第1雌花节位高低、抑制徒长、提高产量等方面,而乙烯利对黄瓜叶片生理活性及品质的影响尚未见报道。本试验旨在通过选用不同浓度的乙烯利,在不同栽培环境下,对不同苗龄的黄瓜幼苗进行处理,以探讨乙烯利处理对黄瓜叶片生理活性、产品品质的影响,为黄瓜高产优质高效栽培提供依据。  相似文献   

9.
脐橙修剪及保果技术1保果永安市在脐橙保果技术上有3种方法:一是在5月上旬对1~3级枝进行环剥保果,一般可比对照增加1倍的产量,不影响树势和第2年产量。二是在5~6月间喷布15×10-62,4-D1~2次,或40×10-6~50×10-6九二○两次,夏...  相似文献   

10.
硒在金菇菌体内的生物转化   总被引:11,自引:1,他引:10  
(研究报导了液体深层培养金针菇(FlammulinavelutipesNJ9601)的富硒能力和生物转化,在添加5~125(×10^-6)硒的范围内,菌丝体富硒的范围为8.2~90.2(×10^-6)添加20(×10^-6)时,菌丝体吸收率最高,为对照的184%,此时菌体生长,可溶性蛋白质,氨基酸,多糖等含量均高于对照组,无机硒经菌体吸收,代谢,转化,其有机化程度在75%以上,分布在硒蛋白(占64  相似文献   

11.
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.  相似文献   

12.
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   

13.
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   

14.
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.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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.  相似文献   

20.
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.  相似文献   

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