油菜钾素营养研究进展

从钾素的生理作用、钾素缺乏与营养诊断、钾素对油菜产量和品质的影响、我国油菜种植区土壤钾素概况以及钾肥施用等方面综述了近年来我国油菜钾素营养研究的状况,并对钾素在油菜上的施用研究方向进行了展望。     

氮、磷、钾对银杏叶黄酮含量与营养生长的效应

通过正交试验，利用营养液盆栽法研究了N，P，K3种大量元素对银杏叶黄酮含量和营养生长的影响。结果表明，处理间叶黄酮含量差异极显著，3种元素对黄酮含量效应大小依次为N，K，P。营养液中N，K，P的质量浓度分别为0．21，0．18，0．7g/L对提高叶黄酮含量的效果最优。银杏新梢的增粗生长，3种元素不同配比间存在极显著差异；N，P对新梢粗生长的主效明显，营养液中N和P的质量浓度以0．28g/L和0．12g/L对新梢粗生长效果最好。     

Potassium distribution in black heartwood of sugi (Cryptomeria japonica) I: Localization in axial parenchyma cells

This is the first report to ascertain potassium location in black heartwood of sugi (Cryptomeria japonica). The objective of this study was to understand the distribution of potassium in sugi black heartwood in connection with anatomical morphology. Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDXA) was used to investigate the distribution of inorganic elements, especially potassium. In black heartwood, potassium was detected in all tissues (tracheids, ray parenchyma, and axial parenchyma), but its concentrations were different in each xylem tissue. Potassium was particularly accumulated in the droplets in axial parenchyma cells. In addition, calcium was also detected in all tissues. Phosphorus sometimes existed in the granules in ray parenchyma cells. From optical microscopy, the axial parenchyma cells were observed to be arranged in a tangential direction on transverse section and the droplets in these cells were distributed in areas of high ash and green moisture content. For red heartwood, potassium detected by SEM-EDXA was far lower in all tissues than in the black heartwood, while the trend for calcium was the converse. Potassium in axial parenchyma cells was more abundant in black heartwood than in typical pale red heartwood.     

钾营养对冬小麦光合作用和衰老的影响

盆栽砂培和田间试验结果表明，供钾不足使小麦生育后期旗叶过氧化物酶活性和丙二醛含量增高，可溶性蛋白质、叶绿素含量和根系活力降低，旗叶光俣速率下降，加速衰老。     

灌溉方式对新疆棉花条田盐分运移的影响

采用土体的双向切片法,研究了膜下滴灌、淹灌两种不同模式下不同土层之间以及膜灌带的不同区域之间盐分分布的差异,进而得出盐分在不同的灌溉方式下的运移规律。结果表明：盐分由于灌水方式不同各处理之间变化趋势不同,同时,由于北疆棉田采用宽窄行的种植模式,宽行和窄行以及膜灌带两侧钾素和盐分的在各土层之间含量也呈现出显著差异。滴灌处理盐分在土壤表层有轻微表积现象,随深度增加盐分含量下降;常规淹灌处理,土壤表层含盐量低于滴灌处理,而随深度增加在0-60 cm深度范围内盐分含量逐渐增加。     

不同钾钙比例对不同烤烟品种的影响

通过对三个供肥水平N：P2O5：K2O：CaO的比例处理L＝1：2：0：2，处理S＝1：2：3：1，处理H＝1：2：5：1和三个烤烟品种：K326、红花大金元、V2的两因素田间试验，结果表明：（1）随着叶龄增加，叶片钾钙含量呈下降趋势，钾钙吸收系数则呈上升趋势。（2）钾效应表现为红大＞K326＞V2，钙效应表现为K326＞红大＞V2。（3）维持较高钙吸收系数的品种其光合色素含量较高，生育期较长。根系活力较强，具较高的总糖、总挥发碱。     

Physicochemical Characterization of Nopal Pads (Opuntia ficus indica) and Dry Vacuum Nopal Powders as a Function of the Maturation

This paper presents the physicochemical and nutrimental characterization of fresh nopal (Opuntia ficus indica, Redonda variety) and nopal powder produced at different stages of development. Nopal powder was obtained by dry vacuum technique using 10² Torr and low temperature (40°C). The results showed that the nutrimental and mineral composition of nopal changes as a function of the maturation as follow: The ash content increases from 18.41 for nopalitos (60 g of weight) to 23.24% (nopal pads 200 g); calcium content increases from 1.52 to 3.72%, while phosphorous exhibits an opposite trend: 0.43 to 0.27%, respectively. Calcium oxalate was determined by X-ray diffraction and SEM microscopy and quantified by using atomic absorption spectroscopy. Calcium oxalate decreases from 7.95 to 3.47 mg/g and the Ca/P ratio varies from 3.6 to 11. The soluble fibre decreases from 25.22 to 14.91%, while insoluble fibre increases from 29.87 to 41.65%. These results suggest that nopal could be an important source of minerals within the diets of people in Mexico and the rest of Latin America.     

施用钾肥对强筋小麦产量的影响

采用盆栽试验方法研究了钾对强筋小麦产量的影响。试验结果表明:施用钾肥增加了小麦的株高、穗长、千粒重及穗粒数,极显著地提高了小麦产量,小麦增产10%~24%。     

不同钾营养效率型玉米品种的苗期生理特性

选用钾高效型玉米品种3份和钾低效型玉米品种1份,以水培的形式,设2种钾浓度梯度,分析4个不同钾营养效率型品种在苗期的一些形态和生理指标的差异。结果表明:不同钾营养效率型玉米品种在2种钾浓度处理下存在着明显的差异性,在低钾浓度处理下,2种钾效率型玉米品种,在5叶期和7叶期时的叶面积、株高、根长、叶绿素以及根系活跃吸收面积都有所降低,钾高效型玉米品种的降低幅度均明显小于钾低效型玉米品种,前者在测量的各方面指标上均好于后者。     

钾肥运筹对中籼稻产量·钾素积累利用的影响

[目的]为杂交中稻的合理施肥提供理论依据。[方法]通过田间试验,研究钾肥运筹对中籼稻产量和钾素积累利用的影响。[结果]施钾可以显著提高水稻产量。在120 kg/hm2施钾量下,钾肥一次性基施或钾肥后移产量差异不明显;而在150 kg/hm2施钾量下,钾肥后移能显著提高水稻产量,比全作基肥处理增产9.56%。钾肥的穗肥追施比一次性基施明显增加拔节至抽穗的吸钾量和比例,提高实粒数、结实率和产量,并显著提高钾素利用效率。[结论]杂交中稻施用钾肥应掌握施中低量钾肥时作基肥的效果较好,而高量钾肥分次施用有明显的增产效果。