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11.
鸡腿葱是山东省莱芜市的特产,全国农产品地理标志。因其感官特殊、品质上乘、风味独持,而深受消费者的青睐。随着市场需求量的增大,鸡腿葱高产稳产的种植技术需求迫切。文章总结了莱芜鸡腿葱种植的关键技术,包括育苗、栽培、病虫害防治以及收获贮藏等,以促进鸡腿葱的高效种植与推广。 相似文献
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采用静态暗箱-气相色谱法研究了冬小麦/大葱轮作体系不同施肥处理下农田N2O排放特征及排放系数,分析了土壤湿度和土壤温度等环境因子对N2O排放的影响。结果表明,农田N2O排放高峰值主要出现在每次施肥+灌溉或强降雨之后的一段时间,大葱生长季排放峰值高且出现的频率比小麦生长季密集;N2O排放通量变化范围为-3.85~507.11μg N·m-2·h-1,平均值为251.63μgN·m-2·h-1,对于不同施肥处理,其年度N2O排放总量介于1.71 kg N·hm-2到4.60 kg N·hm-2之间。整个轮作体系不同处理N2O排放系数介于0.31%到0.48%之间,均值为0.43%;相对比农民习惯(FP)处理,优化施肥(OPT)、优化减氮(OPT-N)以及秸秆还田(C/N)处理均能显著减少N2O的排放,秸秆还田处理和优化减氮处理N2O排放总量比优化处理分别减少了17%和10%。在10℃〈土壤温度(T)s〈20℃时,N2O排放随温度的升高而增加;整个小麦生长季N2O排放随土壤湿度的增加而增加,且达到0.05的显著水平;大葱生长季在20℃〈Ts〈30℃时,土壤水分含量成为主要限制因素,N2O排放与土壤孔隙含水量(WFPS)呈显著指数正相关关系。秸秆还田处理作物产量高于其他处理,是具有减排增产"双赢"效果的农田管理措施。 相似文献
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将“一道清”的高产长效施肥技术在激光诱变选育出的红皮洋葱新品种‘西葱1号’上施用,通过与’常规施肥试验的对比,得出使用这种施肥技术可显著提高肥料利用率25%左右,能满足洋葱生长全过程的需要;还能降低洋葱早期抽薹率50%左右,改善洋葱品质,产量提高5%以上,施肥上用工减少5/4以上。在生产应用上有极好的前景。 相似文献
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Paul van Dijk René A. A. van der Vlugt 《European journal of plant pathology / European Foundation for Plant Pathology》1994,100(3-4):269-277
Flexuous viruses were transmitted from rakkyo (Allium chinense) and wild leek species (especiallyA. commutatum) to plants of crow garlic (A. vineale), by transfer of dry bulb mites. By electron microscope decoration tests using three antisera and by inoculations onto test plants, it was concluded that from each of the two natural host species at least two viruses were isolated. The viruses from wild leeks are both pathogenic onAllium spp. and may be of economic importance. Decoration tests on a virus mixture from shallot obtained earlier, revealed another new mite-borne virus in this species. The mite-borne viruses ofAllium spp. appear to be very common; they are largely diverse and their identification remains difficult. 相似文献
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Manual weeding of intrarow weeds in direct-sown leek and bulb onion crops grown organically can be very labour-intensive. Four field experiments, two in direct-sown leek and two in direct-sown bulb onion were made in this investigation to study the effects of physical and cultural methods on intrarow weed numbers, time consumption for hand-weeding and marketable yield parameters. The physical methods considered were: pre-emergence flaming and harrowing, and post-emergence hoeing close to the row (only leek) and vertical brush weeding. The cultural methods were: seed priming, slurry placement and cultivar choice (only leek). Generally, flaming plus brush weeding gave the highest intrarow weed control at 92% and 87%, respectively, in the two leek experiments and 39% (only brush weeding was effective) and 74%, respectively, in the two onion experiments. Time consumption for hand-weeding after the different treatments was linearly related to the remaining numbers of intrarow weeds, with no significant influences of the experimental factors on the general relationship. Generally, the cultural methods had no significant influence on the effects of physical weeding in terms of their effect against intrarow weeds. They did not affect the tolerance or robustness of the crop plants against negative impact from the physical control methods. However, generally, seed priming and cultivar choice did improve yield in the leek experiments and seed priming also did so in the one experiment with onion. 相似文献
19.
Liu TX 《Pest management science》2003,59(8):904-912
Effects of a juvenile hormone analog, pyriproxyfen, on various developmental stadia of the onion thrips, Thrips tabaci Lindeman, were determined on cabbage leaves in the laboratory. Pyriproxyfen was applied at 0.064 or 0.128 g AI liter(-1) on leaves (residual contact-ingestion), thrips (direct contact) and leaf-thrips (residue contact-ingestion-direct contact). Pyriproxyfen did not have any significant lethal effects on thrips pupae in any treatment. Lethal effects on thrips larvae varied depending on application method and dosage. In the leaf and the leaf-thrips treatments, few larvae and pre-pupae molted to the next stage, and none developed to adults. In contrast, in the thrips-only treatment, pyriproxyfen did not show any significant lethal effects. The developmental times of larvae and pre-pupae were prolonged when larvae were treated with pyriproxyfen, and those of pre-pupae and pupae were shortened when pre-pupae and pupae were treated. The longevity and survival rates of thrips adults were generally shorter when they contacted and ingested pyriproxyfen-treated leaves than those in water control. Significantly fewer progeny (0.22-1.15 larvae per female) were produced by females that had fed on and been in contact with the pyriproxyfen-treated leaves than by those in the water control (11.94 larvae per female). However, the number of progeny produced by the thrips females increased significantly (3.32-7.28 larvae per female) when the females were transferred to untreated leaves after feeding on treated leaves for 5 days; the daily larval hatching pattern was similar to those in water control, indicating that female adults were able to produce viable eggs when untreated food was offered. 相似文献
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S. M. Newman 《Agroforestry Systems》1984,2(1):49-56
Carrots, onions, radishes and peas, growing in pots were placed at various locations in a pear orchard and used as phytometers
to characterise the aerial environment. The growth of plants growing beneath the orchard canopy was not significantly less
than that of phytometers grown in the open. However, the bulb diameter of radish and onion was significantly reduced when
growing immediately beneath pear trees. Radish was selected as a suitable phytometer for further research. 相似文献