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41.
苋菜培养细胞中角鲨烯的提取与含量测定 总被引:2,自引:0,他引:2
[目的]建立苋菜培养细胞中角鲨烯提取与含量测定的方法。[方法]以苋菜叶片为外植体诱导愈伤组织,用皂化和不同有机溶剂浸泡的方法提取苋菜愈伤细胞中角鲨烯,并用HLPC测定其含量。[结果]用皂化法提取苋菜愈伤细胞的角鲨烯含量高于用有机溶剂浸泡方法提取的含量。苋菜愈伤细胞提取的角鲨烯在HLPC上与标准品出峰时间一致,而且该峰与其他峰有很好的分离。[结论]皂化法是提取苋菜愈伤细胞中角鲨烯较好的方法。用HLPC测定苋菜愈伤细胞中角鲨烯含量可行。 相似文献
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在室内条件下,测定了氟磺胺草醚对野苋菜和灰绿黎的杀草活性。结果表明:氟磺胺草醚对野苋菜和灰绿黎的EC50值分为200.282 8 mg/L和233.529 8 mg/L,氟磺胺草醚对野苋菜和灰绿黎具有很好的抑制效果。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(1-2):35-55
Abstract Phosphorus (P) is expensive to the sub‐Saharan African resource‐poor farmers; therefore, there is a need for investigation of locally available alternative P sources to enhance farmers' productivity. Optimum P rate was determined during the early and late rains of 1999. Using the optimum P rate, influences of three P sources ogun rock phosphate (ORP), sokoto rock phosphate (SRP), single super phosphate (SSP) and a control were evaluated on amaranth varieties in 2000 at the vegetable research plots of the National Horticultural Research Institute (NIHORT), Ibadan, Nigeria. In 1999, three grain amaranth varieties (NH84/452, NH84/445, and NH84/493) were combined factorially with four P rates: 0, 30, 60, and 90 kgP/ha. Application of P significantly increased plant height, number of branches, leaf dry weight, and grain yield (GY) per plant. Significant increase in GY was in the order NH/493>NH/445>NH/452. Optimum P rates across varieties for leaf dry‐matter yield was established at 51.8 kgP/ha and for grain yield production was 48.4 kgP/ha. The experiment in the following year, 2000, was a RCB design using the optimum P determined in 1999. Three P sources (ORP, SRP, SSP) and a control were factorially combined with the three amaranth varieties. In the 2000 experiment, grain yield was 21.3, 16.9, 16.0, and 7.8 g/plant, respectively, for SSP, SRP, ORP, and the control. Growth was ranked in the order SSP>ORP>SRP>control. It was concluded for fertilizer recommendation purposes that 50 kgP/ha is optimum for grain amaranth production and that amaranth productivity indices could be alternatively improved with indigenous P sources. 相似文献
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反枝苋Amaranthus retroflexus是一种世界性恶性杂草。为了确定微生物除草剂候选菌Alternaria amaranthi-3防除反枝苋的潜力,通过盆栽试验研究了接种浓度、露期和水乳剂型对A.ama-ranthi-3菌株致病力的影响。结果显示,接种浓度显著影响菌株的致病力,在48h露期条件下,接种孢子浓度为105个/mL时,菌株水剂对反枝苋幼苗生长抑制率为35.55%;浓度为107个/mL时,生长抑制率达到75.25%。露期对该菌株的致病力也有较大影响,在不保湿条件下,菌株水剂对反枝苋的生长抑制率为26.43%,而保湿48h处理的生长抑制率达到77.96%。Span80∶Tween80=1∶3的复配乳化剂和大豆油制备的水乳剂可显著降低露期对菌株防效的影响和提高菌株的致病力,无露期时,菌株水乳剂对反枝苋的生长抑制率达到88.35%,显著高于水剂;48h露期条件下,菌株水乳剂处理的生长抑制率为90.59%,而菌株水剂处理为77.96%。表明通过剂型的改进菌株Alternaria amaranthi-3能有效防除反枝苋。 相似文献
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净作11年的橘园首次套种芝麻,发现园内芝麻青枯病发生严重。为探明芝麻青枯病初侵染源,本研究从芝麻青枯病株上分离到菌株JXRs02,通过形态学、分子生物学以及聚类分析,鉴定其为青枯雷尔氏菌演化型I。利用针刺接种法,将JXRs02菌株接种至柑橘园中的4种杂草凹头苋、青葙、空心莲子草以及加拿大蓬,发现JXRs02能够侵染凹头苋杂草,造成枯萎症状;LAMP检测的结果显示,在凹头苋病株组织内能够检测到青枯雷尔氏菌。依据柯赫氏法则,利用分子生物学方法证明了对凹头苋杂草具有致病性的菌株和造成芝麻青枯症状的病原菌同为青枯雷尔氏菌演化型I。同时发现,在凹头苋、青葙、空心莲子草和加拿大蓬4种杂草的根际土壤中芝麻青枯病菌均能够定殖繁衍。推测凹头苋杂草可能为芝麻青枯病菌的中间寄主,凹头苋、青葙、空心莲子草和加拿大蓬等杂草根际土壤积累的菌源可能为橘园套种芝麻后青枯病的初侵染来源。本研究对制定作物青枯病的防治策略具有一定科学意义。 相似文献
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C4 plants show higher photosynthetic capacity and productivity than C3 plants owing to a CO2-concentrating mechanism in leaves, which reduces photorespiration. However, which traits regulate the photosynthetic capacity of C4 plants remains unclear. We investigated structural, biochemical, and physiological traits associated with photosynthesis and resource use efficiency in 20 accessions of 12 species of Amaranthus, NAD-malic enzyme-type C4 dicots. Net photosynthetic rate (PN) ranged from 19.7 to 40.5 μmol m?2 s?1. PN was positively correlated with stomatal conductance and nitrogen and chlorophyll contents of leaves and was weakly positively correlated with specific leaf weight. PN was also positively correlated with the activity of the C3 enzyme ribulose-1,5-bisphoshate carboxylase/oxygenase, but not with the activities of the C4 enzymes phosphoenolpyruvate carboxylase and NAD-malic enzyme. Structural traits of leaves (stomatal density, guard cell length, leaf thickness, interveinal distance, sizes of mesophyll and bundle sheath cells and the area ratio between these cells) were not significantly correlated with PN. These data suggest that some of the biochemical and physiological traits are involved in interspecific PN variation, whereas structural traits are not directly involved. Photosynthetic nitrogen use efficiency ranged between 260 and 458 μmol mol?1 N s?1. Photosynthetic water use efficiency ranged between 5.6 and 10.4 mmol mol?1. When these data were compared with previously published data of C4 grasses, it is suggested that common mechanisms may determine the variations in resource use efficiency in grasses and this dicot group. 相似文献