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低温胁迫对蓝莓枝条呼吸作用及生理生化指标的影响 总被引:2,自引:0,他引:2
为明确蓝莓枝条不同部位的耐低温能力,利用人工模拟低温胁迫的方法研究了蓝莓1年生枝条尖端、1年生枝条基端和2年生枝条对低温胁迫的生理响应。结果表明:低温胁迫下蓝莓不同部位枝条的各生理指标之间虽然具有一定的相关性,但不同生理指标的相关系数差异较大,即蓝莓枝条不同生理过程对低温的敏感性明显不同。其中,0℃时1年生枝条特别是其尖端的呼吸速率明显高于2年生枝条,但其呼吸作用对低温也特别敏感,当温度降低到-10℃时即均发生明显的降低,且1年生枝条尖端的降低幅度最大。另外,低温胁迫下1年生枝条尖端的丙二醛(MDA)含量和相对电导率增加幅度也明显大于1年生枝条基端和2年生枝条,即1年生枝条尖端对低温胁迫更为敏感。低温胁迫下不同部位枝条虽可以通过增加可溶性糖(SS)和可溶性蛋白(SP)等渗透调节物质,以及增强SOD和POD等抗氧化酶活性的方式来提高其抗寒能力,但当温度降低到-40℃时,不但抑制了蓝莓1年生枝条尖端可溶性蛋白的合成,并且1年生枝条尖端和基端的SOD活性较-20℃时也有不同程度的降低,即-40℃时1年生枝条特别是其尖端蛋白质合成的抑制以及抗氧化酶活性的降低可能是导致其蓝莓在我国北方大兴安岭地区易发生冻、干梢现象的主要原因。而1年生枝条基端和2年生枝条具有较强抗低温能力的原因除了其本身代谢活性较低,对低温不敏感外,低温下有效积累渗透调节物质和增强抗氧化酶的活性在降低其膜质过氧化程度和电解质外渗方面发挥了重要的作用。 相似文献
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以“蓝丰”作为研究对象,将农业生态网技术应用于蓝莓生产中,调查并对比网内和网外的温度、湿度、风速、光强各项指标,同时研究其对蓝莓果实商品价值的影响。结果表明,农业生态网能够避免鸟害减少烂果,增产增收,提高果品经济价值。以期为农业生态网在农作物生产中的应用提供科学的参考。 相似文献
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K. A. Ross D. Ehret D. Godfrey L. Fukumoto M. Diarra 《International Journal of Fruit Science》2017,17(2):202-232
This work examined the processing yields, physico-chemical characteristics, and bioactive properties of Canadian organic cranberry and blueberry pomace and phenolic-enriched extractives. The ethanol extracts from each berry contained three to four times the soluble solids and sugar contents compared to the pomace. The lipid content of organic cranberry pomace (4.44%), cranberry ethanol extractives (3.86%), and blueberry ethanol extractives (4.44%) were significantly lower than the lipid content of the organic blueberry pomace (5.42%). The organic blueberry pomace showed higher protein content (8.41%) than organic cranberry pomace (5.76%); however, both organic cranberry and blueberry ethanol extracts showed similarly low protein contents. Significant differences were observed in the mineral and elemental contents of both pomaces and their extractives. Total phenolics, tartaric esters, flavonols, anthocyanins, and antioxidant activities were increased by two to three times in both organic cranberry and blueberry ethanol extracts compared to their respective pomaces. The major anthocyanins detected in organic blueberry pomace and ethanol extracts were peonidin 3-glucoside, malvidin 3-galactoside, malvidin 3-glucoside, and cyanidin 3-arabinoside. Peonidin 3-galactoside, cyanidin 3-galactoside, cyanidin 3-arabinoside, and peonidin 3-arabinside were the major anthocyanins in the organic cranberry and ethanol extacts. Results indicated that cranberry and blueberry pomace could be used to develop bioactives with antioxidant activity for potential health benefit and/or bioenergy production. 相似文献
6.
基于正交设计的施用硫磺、控水灌溉和施肥对蓝莓生长的影响 总被引:1,自引:1,他引:0
旨在优化高寒地区蓝莓栽培模式,利用正交试验研究了施用硫磺、控水和施肥3个因素对大兴安岭地区蓝莓品种‘美登’植株生长的影响。结果表明:3个因素正交处理对蓝莓生长指标的影响程度较大,不同处理之间各生长参数均存在较大的变异幅度,3个因素之间存在明显的互作效应,并且拮抗效应较小。极差分析结果表明,对蓝莓株高、冠幅和枝条长度影响最大的因素为土壤相对含水率,而对枝条粗度影响最大的因素为施肥。3个因素互作下均表现为各因素的3水平或4水平蓝莓生长性状最优,结合各生长参数的变化结果,建议大兴安岭地区蓝莓品种‘美登’施用硫磺量为70~80 g/m2,施硫酸钾复合肥7.5~10 g/株,土壤相对含水率维持在45%~60%。 相似文献
7.
Lowbush blueberry (Vaccinium angustifolium) is a native plant that is not cultivated, but managed in areas of sufficient plant density to provide commercial yields. A cropping systems study was initiated to compare how organic and three levels of conventional (low, medium and high input) management practices affected soil properties at 12 grower fields in the lowbush blueberry barrens of Maine. The fields under organic and low‐conventional treatments did not receive any fertilizer inputs. The high and medium conventional treatment fields received optimal and reduced diammonium phosphate inputs, respectively. Three measurements of soil P (modified‐Morgan soil test, oxalate extractable and total P) showed no significant effect of management treatment on the phosphorus status of the soils. This suggests that soil P may be leaching below the 0–10 cm rooting zone which was investigated in this study. Equilibrium chemical speciation of soil/water extracts showed that gibbsite was controlling the solubility of Al in these barren soils and that P was undersaturated with respect to amorphous Al(OH)2PO4. A laboratory one‐point P sorption study showed that dissolved organic matter derived from the organic pad sampled from the study sites did not inhibit the adsorption of the added P. This suggests that addition of carbon‐rich soil amendments such as compost may not increase P bioavailability of these acidic soils with high Al (oxy)hydroxide (gibbsite) mineral content. 相似文献
8.
Takuya Ban Mihoko Kugishima Tsuneo Ogata Shuji Shiozaki Shosaku Horiuchi Hisafumi Ueda 《Scientia Horticulturae》2007
Effect of ethephon (2-chloroethylphosphonic acid) application on rabbiteye blueberry fruit quality during the growth period was investigated. Ethephon treatment stimulated the decrement of titratable acidity, anthocyanin accumulation and fruit softening 4 days after treatment and the promoting effects continued through the investigation period. The ripening promotion effect of ethephon on total soluble solids content was observed only 8 days after treatment. Ethephon treatment did not affect the fruit enlargement during the investigation period. From these results, it is concluded that ethephon application for rabbiteye blueberry promote the fruit ripening, but the stimulatory effects of ethephon on fruit ripening were different in degree on each ripening characters. 相似文献
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半高丛越橘果实香气成分的GC—MS分析 总被引:5,自引:1,他引:4
采用静态顶空和气相色谱—质谱联用技术,以半高丛越橘品种北陆、圣云和北蓝为材料,研究了半高丛越橘果实香气成分。结果表明,半高丛越橘以醇类、酯类、萜类和酮类物质为主。共检测出39种挥发性成分,其中北陆检测出16种,圣云17种,北蓝23种。2-甲基丁酸乙酯和β-芳樟醇是半高丛越橘的特征香气,构成了半高丛越橘特有的香气,同时乙酸丁酯、2-丁酮、D-柠檬酸为北陆的特征香气,丁酸乙酯、2-丁酮为圣云的特征香气,丁酸乙酯、乙酸己酯、己醛为北蓝的特征香气成分,品种间特征香气的差异形成了半高丛越橘品种间独特的风味。 相似文献