钾营养对甘薯块根薄壁细胞微结构、14C同化物分配和产量的影响

选用徐薯 18号为材料 ,通过大田试验研究了供钾水平对甘薯块根薄壁细胞显微和超微结构、块根呼吸速率和ATP含量、14C同化物分配和产量等的影响。结果表明 ,施用适量钾肥 ,甘薯块根薄壁细胞膜结构完整、清晰 ,内含较多的线粒体和质体 ,胞质较丰富 ;块根的呼吸速率和ATP含量较高 ,有利于提高块根“库”的活性。适量供钾 ,增加单位体积块根内的淀粉粒数 ,提高块根淀粉含量 ;促进光合产物由叶片向块根的运输 ,提高了14C同化物在块根中的分配比例 ;促进块根迅速膨大 ,增加单薯重 ;提高块根产量     

钾对甘薯同化物积累和分配的影响

试验研究了不同供钾水平对甘薯产量、干物质积累与分配的影响。结果表明：在一定范围内，提高供钾水平可以提高产量，降低光合势，增加净同化率，有利于干物质的积累；钾的充足供应，可以促进光合产物向地下运输，提高干物质在块根中的分配率，并提高块根中淀粉含量，降低茎中淀粉含量，有利于物质的运转；充足的钾肥，可降低后期功能叶片中蛋白质的含量和过氧化氢酶的活性，有效地防止了地上部旺长，促进生长中心向块根转移。     

钾对甘薯同化物积累和分配的影响

试验研究了不同供钾水平对甘薯产量、干物质积累与分配的影响。结果表明:在一定范围内,提高供钾水平可以提高产量,降低光合势,增加净同化率,有利于干物质的积累;钾的充足供应,可以促进光合产物向地下运输,提高干物质在块根中的分配率,并提高块根中淀粉含量,降低茎中淀粉含量,有利于物质的运转;充足的钾肥,可降低后期功能叶片中蛋白质的含量和过氧化氢酶的活性,有效地防止了地上部旺长,促进生长中心向块根转移。     

乙酰胆碱、LatA和FAA对萝卜韧皮部同化物运输的影响

利用乙酰胆碱 (Ach)、微丝解聚剂 (LatA)和维管束固定剂 (FAA)处理萝卜的韧皮部 ,以叶片中可溶性糖和淀粉含量以及14 C 同化物从叶片中的输出量为指标 ,研究 3种药剂对韧皮部同化物运输的调控作用。结果表明 ,低浓度的Ach可有效地促进14 C 同化物向肉质根的运输 ,而LatA和FAA处理则有效抑制14 C 同化物向肉质根的运输。     

钾营养对甘薯某些生理特性和产量形成的影响

田间试验结果表明 ,适量供钾可增加甘薯功能叶和块根中的ATP含量 ,增加块根中的脱落酸 (ABA)含量 ;提高叶片中可溶性碳水化合物的装载效率和块根中可溶性碳水化合物的卸载效率 ,促进碳水化合物由叶片向块根的运输 ;增加块根中的淀粉含量 ,提高块根干重与单株干重的比率 ,促进块根迅速膨大 ,增加块根产量     

水分胁迫后复水对苹果结果树体内~(14)C-光合产物分配的影响

利用14 C示踪方法研究胁迫后复水对14 C 光合产物从苹果结果树叶片的输出及其在体内的分配影响。结果表明 ,胁迫期间14 C 光合产物合成和输出量均减少 ,同化物向枝、干的分配率增加 ,向新梢 (幼叶 )和果实的分配率下降 ;胁迫后复水 ,同化物的合成和输出均较胁迫条件下改善 ,但仍未完全恢复到充分供水的水平 ,同化物优先运往新梢 (幼叶 ) ,果实未获得较多的同化物。     

重庆市开州区李子营养元素分析及其施肥措施

对重庆市开州区6个主要李子园采集的15个叶样的11种营养元素进行分析测定。结果表明,李子叶片中氮、磷、钾、钙、锰和硼元素含量普遍偏高,镁、锌、铜元素含量大部分在适宜指标范围内,普遍缺铁元素。元素含量偏高的李子园氮占100%、磷占100%、钾占60%、钙占93%、锰占73%、硼占60%,缺铁元素的李子园占84%。根据叶片营养丰缺状况配方施肥,调整开州区李子园施肥措施,重点控氮、磷、钾、钙、锰、硼,补铁,从而全面提高开州区李子园产量和质量。     

温州蜜柑叶片黄化果园土壤及叶片的养分含量特征

弄清叶片黄化柑橘园土壤与叶片的养分含量特征,为改善柑橘园营养状况,提高柑橘产量和品质提供理论与技术支撑。通过对黄化和无黄化温州蜜柑园土壤、叶片的养分含量进行分析,研究影响温州蜜柑叶片黄化的关键因子。结果表明,温州蜜柑叶片的钙、镁、硼含量与SPAD值呈显著或极显著正相关,叶片黄化是由叶片中钙、镁、硼含量不足所造成的,属于综合缺素型,同时叶片中钾、铁、锰含量较高,叶片对钙、镁、硼的吸收与对钾、铁、锰的吸收之间存在相互拮抗的关系;土壤酸化是叶片黄化的主要驱动因子,pH值较低一方面降低了土壤中钙、镁、硼的有效性,另一方面,土壤中较高的铁、锰含量抑制了柑橘对钙、镁、硼的吸收,最终导致叶片因缺钙、缺镁、缺硼而出现黄化。喷施含钙、镁、硼的叶面肥料,防止土壤酸化是改善温州蜜柑叶片黄化的有效措施。     

密度和追肥时期对大穗型小麦~(14)C-同化作用及其分配的调控效应

本研究结果表明 ,挑旗期叶片 (尤其是旗叶和倒 2叶 )是大穗型品种兰考 90 6最主要的同化器官 ,其同化量占单茎总同化量的 90 %以上 ,而叶鞘的同化量仅占1 0 %以下。密度过大不但抑制14 C 同化速率 ,而且降低14 C 同化物运输分配效率。适当推迟追肥有利于提高单茎同化量和同化物的运输分配效率。     

锰与硼喷施对紫花苜蓿产量和矿质元素含量的影响

采用叶面喷施的方法,研究不同水平锰与硼对紫花苜蓿草产量和矿质元素含量的影响.结果表明,喷施锰、硼促进了紫花苜蓿草产量的增加,适量则效果显著(P < 0.05),以施锰浓度200 mg·L-1(Mn2处理)和硼浓度600 mg·L-1(B3处理)效果最好,草产量比对照分别提高809.49和1 065.35 kg·hm-2;喷施锰肥能显著提高锌和锰的含量;适量则能显著提高紫花苜蓿磷、钴、硒、铁和钼的含量,喷施锰肥降低了钙和铜的含量,适量则影响显著;喷施锰肥,硼的含量略有降低;且锰含量与施锰量呈正相关,硒、铜含量与施锰量呈负相关;而铁、锌含量随施锰量增加呈先升后降趋势.喷施硼肥显著提高了锌和磷含量,显著降低了钙、钼、硒的含量,显著提高钴、铁、锰、硼的含量,喷施硼肥,铜的含量略有下降;且锌、硼含量与施硼量呈正相关,铁、钙、钼、铜、硒含量与施硼量呈负相关;而锰、磷含量随施硼量增加呈先升后降趋势.     

Boron and ectomycorrhizal influences on mineral nutrition of container‐grown Pinus ehinata mill

Boron fertilization and inoculation with Pisolithus tinctorius (Pers.) Coker and Couch increased foliar and total seedling nutrient content of boron, calcium, copper, iron, potassium, magnesium, manganese and phosphorus in shortleaf pine seedlings (Pinus echinata Mill.). Noninoculated seedlings fertilized with boron showed no increase in nutrient content other than B. The increase in nutrient content of inoculated seedlings fertilized with boron was correlated with increased mycorrhizal infection. Boron fertilization may affect indirectly the mineral nutrition of tree seedlings by increasing mycorrhizal fungi colonization of their roots.     

Mineral Nutrition Of ‘Petopride’ Processing Tomato Under Partial Rootzone Drying

Information is scant on the mineral nutrition of plants undergoing partial rootzone drying (PRD). Researchers applied PRD to ‘Petopride’ tomato in a glasshouse by alternating irrigation to one side of the plant with half of the water in control (C). Roots in PRD treatment had higher magnesium (Mg) and copper (Cu) than C roots. Leaves in PRD treatment had lower P and higher K than C leaves. Minerals in leaves of C and PRD were within literature reported sufficiency ranges. Fruit of the PRD treatment had higher nitrogen (N) and zinc (Zn), but lower phosphorus (P), calcium (Ca), manganese (Mn) and boron (B) than C fruit. Mineral nutrition of fruit was most affected by PRD compared to that of leaf and root. Fruit of the PRD treatment had a higher incidence of blossom end rot (BER) than C fruit. Incidence of BER notwithstanding, although PRD affected the mineral nutrition of the tomato plant, there was no evidence that the lower yield in PRD was due to poor mineral nutrition.     

Soil water content,absorption of nutrient elements,and responses to fertilization of sunflower: A case study

Sunflower is considered to be a drought tolerant crop due to its root system. In Argentina, water availability and mineral nutrition are the main factors determining yield. We evaluated the behavior of a sunflower hybrid subjected to fertilization in a period of drought. A trial with the hybrid Paraiso 5 was carried out on a Typic Hapludoll located in western Buenos Aires province. The six treatments were: control; 150 kg or 300 kg available nitrogen (N) ha^‐1 (Native N supplemented with fertilizer); 150 kg or 300 kg available N ha^‐1 (Native N supplemented with fertilizer) plus other macro‐ and micronutrients, and macro‐ and micronutrients without N. Leaf area, plant biomass, root biomass, and yield components were determined. Plant tops and grain were analyzed for N, phosphorus (P), sulfur (S), potassium (K), calcium (Ca), magnesium (Mg), boron (B), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn). Soil water content to a 1.2 m depth was measured periodically. At sowing, soil moisture was adequate, but during the first two months, the soil water content dropped to near the wilting point. Roots were largely located in the first 10 cm and dropped abruptly at deeper depths. The highest grain yield resulted from the highest N rates, but there were no effects from other nutrient elements. The oil content was not affected by these treatments. The chemical composition of the straw showed significant differences in N, P, S, and Mn concentration. In grain, only N increased as a response to N fertilization. This hybrid absorbed most nutrient elements during the first half of the life cycle and this corresponded to a time of drought conditions. Apparently roots are able to absorb water from the deep soil depths and still absorb nutrient elements from top soil. These traits might be crop strategies to respond to fertilization under drought.     

Mineral acquisition by arbuscular mycorrhizal plants

Arbuscular mycorrhizal fungi (AMF) benefit plants by allowing them to grow and produce in relatively harsh mineral stress environments. This has been attributed extensively to ability of AMF to expand the volume of soil for which mineral nutrients are made available to plants compared to what roots themselves would contact. This article reviews the effects of AMF on enhancing/reducing acquisition of phosphorus (P), nitrogen (N), sulfur (S), boron (B), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), zinc (Zn), copper (Cu), manganese (Mn), iron (Fe), aluminum (Al), silicon (Si), and some trace elements in plants. The nutrients enhanced most in host plants grown in many soils (e.g., high and low soil pH) are P, N, Zn, and Cu, but K, Ca, and Mg are enhanced when plants are grown in acidic soils. Many AMF have also the ability to ameliorate Al and Mn toxicities for plants are grown in acidic soil.     

Accumulation of nutrients at the surface of roots of blight‐affected orange trees

Abstract

Soil pH and the levels of potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), and zinc (Zn) in the soil at the root surface and the surrounding soil were compared under healthy and citrus blight‐affected orange trees at two locations. The feeder roots were also analyzed for these elenents. Potassium, Ca, and Mg were highest in the rhizosphere of blighted trees, with some, but lower accumulation around healthy roots. Potassium was higher and Fe, Mn, and Zn were lower in feeder roots of blighted than of healthy trees.     

磷钾硼锌肥对百合、白术产量和养分吸收的影响

在田间试验条件下研究了不同营养元素对百合、白术产量和养分吸收的影响。两年结果表明,在河沙土和灰泥土上,施用磷、钾、硼和锌肥的百合产量分别平均增产5.1%、33.5%、22.3%、16.3%和16.2%、12.5%、2.1%、6.1%,在灰泥土上,白术产量分别平均增产8.6%、34.6%、9.1%、5.8%,百合施用钾、硼和锌肥的增产效果大于白术,而白术施磷的增产效果大于百合。施磷肥能促进百合和白术对氮、磷、钾和硼的吸收,而降低对锌的吸收;施钾、硼和锌肥能增进百合和白术的氮、磷、钾、硼和锌养分的吸收量。百合和白术吸收的养分量表现出钾>磷>锌>硼。百合和白术吸收的氮、磷、钾和锌主要分配在鳞茎和根状茎部分,吸收的硼主要集中在茎叶部分。平衡施肥可提高药用部分(鳞茎和根状茎)的磷、钾和锌养分的分配比率。     

Nutritional Status,Yield, and Fruit Quality of “Encore” Mandarin Trees Grown in Two Sites of an Orchard with Different Soil Properties

Abstract

The nutrient status [annual fluctuation of leaf nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), and zinc (Zn)], yield and fruit quality [soluble solids concentration (SSC), titratable acids (TA), SSS/TA and juice content] of “Encore” mandarin trees cultivated in two sites of the same orchard were studied. The trees were grafted on Carrizo citrange rootstock and grown under identical conditions, apart from some soil properties. Soil B (site B of orchard) contained more K, Ca, Mg, and organic matter than soil A (site A of orchard). The patterns of annual variation of leaf nutrient concentrations were similar in both soils, although leaf concentrations of Ca, Mg, Mn, and Fe in soil A were significantly higher than those of soil boron (B), while leaf K concentrations were significantly lower. The mineral analyses of the leaves revealed some interesting antagonisms between K–Mg, K–Ca, and K–Mn. Manganese deficiency was especially limited in the trees grown in soil B. The average fruit yield per tree in soil A, on two-year basis, was significantly higher than this in soil B. The significantly higher water infiltration rate in soil B, in contrast to soil A, seemed to be the dominant factor responsible for the differences among the two sites in yielding and leaf mineral composition.     

含钼袋控复混缓释肥对土壤酶活性及桃树植株生长的影响

以2年生"瑞蟠21/毛桃"为试材,通过调控袋控复混缓释肥钼元素含量(0 g/袋:普通袋控复混缓释肥;0.1 g/袋:含钼袋控复混缓释肥),探究含钼袋控复混缓释肥对盆栽桃树土壤酶活性、养分吸收及植株生长的影响。结果表明,与普通袋控复混缓释肥相比,含钼袋控复混缓释肥处理显著提高土壤中蔗糖酶、脲酶、磷酸酶和过氧化氢酶活性,施肥后30,60天分别提高6.99%,7.61%,12.27%,22.86%和6.31%,11.58%,9.05%,32.14%,且差异显著;含钼袋控复混缓释肥处理提高土壤中全钼含量,增加侧根数量,与普通袋控复混缓释肥相比,根系活力、总根长、总表面积和总体积分别提高7.88%,6.12%,3.95%和9.19%;根冠比提高6.92%,干物质总量提高9.99%。与普通袋控复混缓释肥处理相比,含钼袋控复混缓释肥处理植株叶、侧枝和根部全钼、全氮和全磷含量显著提高,但全钾含量无显著差异,并提高叶、侧枝和根部钙、镁、锌和硼等元素含量;显著提高桃树叶片叶绿素含量和净光合速率。研究表明,含钼袋控复混缓释肥可提高土壤酶活性和桃幼树根系活力,增加侧根数量,提高根冠比,并提高植株叶片净光合效率,促进桃树对氮、磷、硼和锌等元素的吸收,从而促进桃树植株的形态建成。