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不同地膜与覆盖方式土壤水温与作物增产效应 总被引:5,自引:0,他引:5
通过大田试验研究了不同地膜(宽幅普通地膜、窄幅普通地膜、宽幅微孔地膜与窄幅微孔地膜)与不同覆盖方式(平铺覆盖和起垄覆盖)下土壤水分和温度的动态变化规律以及对玉米生长发育、产量和水分利用效率的影响。结果表明,不同地膜与覆盖方式都具有明显的增温保水作用,且增温作用强于保水作用,增温作用主要表现在玉米生育前期,显著促进了玉米前期生长,为后期生殖生长奠定了良好的基础。玉米产量均显著高于CK,增产原因主要是显著增加了玉米百粒重,水分利用效率也显著高于CK。在试验区低温干旱并存的气候条件下,宽幅普通地膜平铺覆盖是一种简单、低成本、高效的覆盖栽培方式,能有效提高水分利用率,增加表层土壤温度,显著提高玉米产量,实现最大的经济效益。 相似文献
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为了优化霉菌产酶条件,获得较可靠的酶活性测定结果,采用两种酶活性测定方法,选用黑曲霉菌株,在配料中添加磷酸二氢钾等单因素试验的基础上,又进行了复因素试验,选出黑曲霉产纤维素酶的最佳添加物组合,最后测定发酵物的主要营养成分。结果表明,玉米秸秆中加入1.8倍的水,添加磷酸二氢钾0.25%、硫酸铵1.00%~1.25%、蔗糖0.50%,可以使黑曲霉菌株产CMCase、FPase酶活性达到最高;玉米秸秆经黑曲霉菌株发酵后粗蛋白提高了1.2倍,而粗纤维、中性洗涤纤维、酸性洗涤纤维分别下降了34%、19%和23%左右;利用CMCase、FPase酶活性两种方法评价黑曲霉菌株产纤维素酶的能力是可行的,整个实验中从CMCase法和FPase法得出的结论基本一致,且FPase法操作步骤简单,成本低,较CMCase法精确度高。 相似文献
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本研究以2013-2022年山西省审定的683个普通玉米品种为材料,按春播特早熟I区、春播特早熟Ⅱ区、春播早熟区、春播中晚熟区、机收组和南部复播区6个不同区组分类,分析玉米品种的品质变化趋势。4个品质指标分析结果显示,中晚熟区品种容重含量平均值最高,特早熟I区品种最低,两者间差异显著(P<0.05);粗淀粉含量年度变化规律整体呈上升趋势。各品质指标在不同区组间的变异,特早熟I区最大,早熟区次之。未来5~10年山西省玉米选育品种和审定上,中晚熟玉米品种的比例会继续增多。 相似文献
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This paper explores the feasibility of particle-based detection and grading of seed vigor based on a self-built seed single-granulation device using near infrared spectroscopy (NIRS). Sweet corn with uniform kernel size was used for this study. The seed samples were divided into three types, they were normal seeds, artificially aged seeds and heat-damaged seeds. A 2-part spectral acquisition of each seed were performed, one for the collection of seeds that fall into the detection zone within the separation pipe, another was on the static platform, whose collection was performed on 5 faces of each seed. Partial least squares discriminant analysis (PLS-DA) was used to classify the original data of the seeds. In the 2 parts, the discriminant results of the unprocessed normal seeds and the artificial accelerated aging seeds, the untreated normal seeds and the heat-damaged seeds showed that classification accuracy was higher than 98%. The research indicates that the spectral data of different positions of seeds can reflect their activity information, and it is feasible to detect and classify seeds in real time in the detection area of the separation pipeline. 相似文献
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In-field management practices of corn cob and residue mix (CRM) as a feedstock source for ethanol production can have potential effects on soil greenhouse gas (GHG) emissions. The objective of this study was to investigate the effects of CRM piles, storage in-field, and subsequent removal on soil CO2 and N2O emissions. The study was conducted in 2010–2012 at the Iowa State University, Agronomy Research Farm located near Ames, Iowa (42.0°′N; 93.8°′W). The soil type at the site is Canisteo silty clay loam (fine-loamy, mixed, superactive, calcareous, mesic Typic Endoaquolls). The treatments for CRM consisted of control (no CRM applied and no residue removed after harvest), early spring complete removal (CR) of CRM after application of 7.5 cm depth of CRM in the fall, 2.5 cm, and 7.5 cm depth of CRM over two tillage systems of no-till (NT) and conventional tillage (CT) and three N rates (0, 180, and 270 kg N ha−1) of 32% liquid UAN (NH4NO3) in a randomized complete block design with split–split arrangements. The findings of the study suggest that soil CO2 and N2O emissions were affected by tillage, CRM treatments, and N rates. Most N2O and CO2 emissions peaks occurred as soil moisture or temperature increased with increase precipitation or air temperature. However, soil CO2 emissions were increased as the CRM amount increased. On the other hand, soil N2O emissions increased with high level of CRM as N rate increased. Also, it was observed that NT with 7.5 cm CRM produced higher CO2 emissions in drought condition as compared to CT. Additionally, no differences in N2O emissions were observed due to tillage system. In general, dry soil conditions caused a reduction in both CO2 and N2O emissions across all tillage, CRM treatments, and N rates. 相似文献