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851.
852.
Ultralow oxygen (ULO) treatments with different oxygen levels, treatment times, and temperatures were studied to determine effects on western flower thrips mortality and postharvest quality of iceberg lettuce. Thrips mortality increased with reduced oxygen level and increased treatment time and temperature. At 0.003% oxygen, over 99.6% mortality rates of thrips were achieved in three ULO treatments of 2, 3, and 4 d at 10, 5, and 1 °C, respectively. No treatments caused injury to lettuce surface leaves and there was no reduction in visual quality for treated lettuce. However, about 9–33% of lettuce heads sustained injury to heartleaves. The 2 d ULO treatment with 0.003% oxygen had the lowest injury rate to heartleaves and the injury increased with increased treatment duration. The amount of injured leaves was small (<2 g per head). There were also some variations among the lettuce cultivars in susceptibility to heartleaf injury by ULO treatments. Four out of eight cultivars tested tolerated the 2 d ULO treatment at 10 °C without any injury. Therefore, ULO treatment has potential to be developed as an alternative postharvest treatment for western flower thrips on iceberg lettuce. 相似文献
853.
Objective:To evaluate the short-term therapeutic effects of TCM for IgA nephropathy in children.Methods:Sixty-two children with primary IgA nephropathy diagnosed for the first time by renal biopsy in t... 相似文献
855.
厦门地区草本花卉植物资源及其园林应用 总被引:2,自引:2,他引:0
介绍了厦门地区的自然条件及其草本花卉植物资源,并探讨了其在园林绿化中的应用。 相似文献
856.
857.
《Communications in Soil Science and Plant Analysis》2012,43(2):177-188
A hydroponics experiment was conducted to study the effect of humic acid (HA) on gerbera (Gerbera jamesonii L.) cv. Malibu in different diluted nutrient solutions. The HA (500 mgL?1) was added to a nutrient solution (NS) of gerbera with two dilution levels of NS, ½ NS and ¼ NS, and full-strength nutrient solution (NSc). The HA application compensated for nitrogen, magnesium, and iron deficiency in the ½ NS. Nutrient utilization efficiency (NUTE) of nitrogen in shoot decreased and that of Fe increased in the ½ NS compared with the ¼ NS when HA was applied. The number of harvested flowers per plant was the greatest in the NSc and the ½ NS with incorporating HA. Flower vase life improved by increasing NS level (9.33 days). It seems HA could be successfully considered as a compound to decrease nutrients input in gerbera hydroponics production. 相似文献
858.
859.
[目的]对吉林西部宜农地进行生态适宜性评价,以期为农业资源有效利用及土地利用结构调整提供依据。[方法]基于模糊数学方法,依据系统性、主导性、有效性、可行性原则,构建评价指标体系;根据耐性定律,按照农作物生态幅要求确定合理评价标准;原始数据基于GIS技术处理,应用EXCEL中VBA程序完成评价计算。[结果]吉林西部宜农Ⅰ等地5512km2、Ⅱ等地25985km2、Ⅲ等地7907km2,不宜农地6312km2。根据评价结果,土地利用调整的重点区域是镇赉县、大安县、乾安县、通榆县、长岭县西部,改善灌排条件、治理土地盐碱化、退耕还林还草是土地利用调整方向。[结论]该研究结果为吉林西部农业资源有效利用及生态环境建设提供了依据。 相似文献
860.
J. M. Van Der Wolf J. R. C. M. Van Beckhoven E. De Boef N. J. M. Roozen 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(2):51-60
Sixteen bacterial strains, cross-reacting with antibodies againstErwinia chrysanthemi (Ech), were isolated from potato peel extracts, ditch water, and the rhizosphere of wheat, onion, sugar beet and chicory using the immunofluorescence colony-staining procedure. Based on fatty acid profiles, isolates were classified as belonging to thePseudomonas fluorescens group.These strains, together with two previously isolated cross-reactingP. fluorescens strains, crossreacted with polyclonal antibodies against Ech in immunofluorescence cell-staining, Ouchterlony double diffusion, and ELISA. Seventeen strains also reacted strongly with monoclonal antibodies against the lipopolysaccharides (LPS) of Ech in ELISA.Cell envelopes (CE) and proteinase-K-treated CE (mainly LPS) of cross-reacting bacteria were further characterized with SDS-PAGE and Western blotting. Based on CE protein and LPS patterns, the cross-reacting bacteria were classified into two groups, each existing of two subgroups. Both CE and proteinase-K-resistant antigens strongly cross-reacted on immunoblots with antisera against a wild type strain of Ech. With an antiserum against a LPS O-chain lacking mutant of Ech only protein bands but no proteinase-K-resistant antigens were detected on immunoblots. These data suggest that in all cases the highly antigenic LPS O-chain is responsible for the cross-reactions. 相似文献