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21.
2种氮源与双氰胺配施对温室芹菜氮素吸收和营养品质的影响 总被引:4,自引:0,他引:4
采用盆栽试验研究了2种不同氮源(尿素氮、农家肥氮)与硝化抑制剂双氰胺(DCD)配施后对温室芹菜氮素吸收和营养品质的影响。结果表明:尿素(Urea)和腐熟牛粪(Dung)分别与DCD配施在一定程度上均可促进芹菜产量的提高和品质的改善,减少土壤中硝态氮含量,降低芹菜体内硝酸盐累积,显著提高氮素利用率。与单施肥料相比,Urea+DCD和Dung+DCD可使土壤中铵态氮含量增加22.71%~92.97%,硝态氮含量降低12.28%~56.73%;可使芹菜茎、叶吸氮量分别增加29.24%~74.89%,30.89%~66.33%,地上部氮素利用率分别提高到16.85%和30.30%。同时,Urea+DCD和Dung+DCD还可促进芹菜产量和株高的增加,但差异未达到显著性水平(P0.05)。芹菜体内硝酸盐含量则分别降低37.05%,17.18%(茎),25.21%和7.63%(叶),并且还能显著提高芹菜中可溶性糖、蛋白质、游离氨基酸和Vc含量。综合比较可知,尿素和DCD配施在减少氮素损失,降低芹菜体内硝酸盐含量以及提高营养品质方面的综合效果较佳。 相似文献
22.
在传统真空包装工艺的基础上,研究了无菌真空热包装生产工艺。通过进行产品感官评定、VC测定和菌落总数测定,对无菌真空热包装和传统真空包装两种工艺对比分析,结果表明无菌真空热包装工艺是可行的,并具有一定优势。 相似文献
23.
T. J. Wicks 《Crop Protection》1990,9(6):433-438
Propiconazole was more effective than either triadimenol or hexaconazole when applied after infection, for the control of Septoria apiicola on celery seedlings. In three out of four glasshouse experiments, 25 mg propiconazole I−1 controlled S. apiicola completely when applied within 3 days after inoculation. Propiconazole and triadimenol at 5–15 mg l−1 were also effective when applied 2 days after inoculation. Soil applications of a granular formulation of triadimenol (up to 20 mg per plant) controlled S. apiicola for 5 weeks on celery seedlings grown in pots and, in the field, granules at 100 mg per plant applied at planting were effective for 6 weeks. In two other field experiments the most effective treatments were foliar sprays of 25 mg propiconazole l−1 applied every 7–10 days with or without the addition of anilazine or chlorothalonil. 相似文献
24.
研究了过氧化氢、柠檬酸与氯化钙组合,以及不同包装材料高密度聚乙烯薄膜(HDPE)、普通聚乙烯薄膜(PE)及低密度聚乙烯薄膜(LDPE)对鲜切西芹的保鲜作用.试验结果表明,过氧化氢+柠檬酸+氯化钙组合时鲜切西芹有保鲜作用,可降低失重率,使呼吸代谢、相时电导率处于较低水平,鲜度指数也明显高于对照.LDPE,HDPE,PE三种包装材料对鲜切西芹的保鲜效果影响不明显.0.15%H2O2+0.1%CA+0.4%CaCl2组合对鲜切西芹的保鲜效果最好,贮藏9 d时,鲜度指数仍达到76.9%. 相似文献
25.
Cytological and genetical studies of a male sterile celery 总被引:6,自引:0,他引:6
Summary The inheritance and nature fo male sterility of a cerley (Apium graveolens L.) strain (MS1) is reported. Male sterility in MS1 is determined by a a recessive genotype for a single locus. Tests for linkage with the isozyme chromosome markers SDH-1 and PGM-1 were negative. MS1 male sterility was associated with a defective tapetum characterized by prominent vacuoles and premature degeneration. The stamens in the male sterile strain persisted in the flowers up to stigma receptivity, while in the male fertile plants they dropped before style expansion. The male sterile flowers produced normal amounts of nectar, resulting in cross pollination by various species of pollinators. It was estimated that the sterile strain produced 30% less seed than normal male fertile. Its possible use for hybrid celery seed production is discussed.Research supported by grants from the California Celery Research Board and BARD I-483-82. 相似文献
26.
The aim of this laboratory study was to investigate the effect of straw and vinasses on the nitrogen (N) mineralization-immobilization turnover of celery residues during two periods (each simulating a time period from autumn till spring) under laboratory conditions. During the first period (1-198 d), 15N-labelled celery residues (1.1 g dry matter (DM) kg−1 soil) were incubated together with straw (8.1 g DM kg−1 soil), aiming to immobilize the N released from celery residues, followed by an incorporation of vinasses (1.9 g DM kg−1 soil) after 84 d, with a view to remineralizing the immobilized celery-N. During the second period (198-380 d), the experimental set-up was repeated, except that non-labelled celery residues were used. Total N, mineral N and their 15N enrichments as well as microbial biomass N were determined at regular time intervals. During both periods, mixing celery residues with straw significantly increased microbial biomass N (90.5 and 40.5 mg N kg−1 extra compared to celery only treatment) and decreased the amount of mineral N (reduction of 56.1 and 45.9 mg N kg−1 soil compared to celery only treatment) and the celery-derived mineral 15N (0% of mineral celery-derived 15N in straw treatment compared to 35% of mineral celery-derived 15N in celery only treatment). After maximum immobilization, a natural remineralization (without addition of vinasses) of 32.2 (at day 198) and 11.1 mg N kg−1 soil (at day 380) occurred in the straw treatment, but the mineral N content remained significantly lower than in the celery only treatment during the complete experiment, and the amount of remineralized celery-15N was very low (5.4% of celery-derived 15N after 380 d). Vinasses caused no real priming effect, although it did slightly increase the amount of remineralized celery-15N (+6.4% of celery-derived 15N at day 380 compared to the straw treatment), probably due an apparent added N interaction caused by displacement reactions with the soil microbial biomass. 相似文献
27.
为探讨油菜素内酯(BR)促进芹菜中阿维菌素和辛硫磷残留的降解效果,以芹菜为试验材料,采用QuEChERS法结合高效液相色谱(HPLC)技术,研究了阿维菌素和辛硫磷在芹菜上自然降解及油菜素内酯对其降解的影响。结果表明,喷施1.8%阿维菌素乳油,芹菜的安全采收期为21 d,半衰期为6.60 d;喷施40%辛硫磷乳油,芹菜的安全采收期为14 d,半衰期为3.04 d。BR能够有效促进阿维菌素和辛硫磷的降解,降解效果优于自然降解,且以0.1 mg·L-1BR为最适喷施浓度,2次为最适喷施次数。阿维菌素在最适浓度0.1 mg·L-1BR处理1次条件下半衰期为4.03 d,安全采收期为14 d,较自然降解提早7 d;最适2次BR处理下半衰期为2.11 d,安全采收期为7 d,较自然降解提早14 d。辛硫磷在最适浓度0.1 mg·L-1 BR处理1次条件下半衰期为1.83 d,安全采收期为7 d,较自然降解提早7 d;最适2次BR处理下半衰期为1.05 d,安全采收期为7 d,较自然降解提早7 d。最佳喷施条件下,BR对辛硫磷的降解效果优于阿维菌素的降解效果。本研究可为芹菜产品农药残留水平安全控制提供科学依据,为蔬菜产品农药残留降解研究提供参考。 相似文献
28.
通过对鲜切芹菜表面微生物的检测,发现从原料到成品各环节存在不同程度微生物污染,为建立鲜切芹菜安全卫生质量控制体系提供参考依据。 相似文献
29.
30.
水芹和旱芹的营养成分分析 总被引:1,自引:0,他引:1
以常规方法对毕节水芹菜和旱芹菜的营养成分含量进行测定和比较分析.结果表明:水芹菜的蛋白质、维生素B1、维生素E、胡萝卜素、钾、钙、磷、铜和硒的含量均比旱芹菜高;而碳水化合物、粗纤维、维生素A、维生素C、钠、铁、镁和锌的含量则比旱芹菜低. 相似文献