Jerusalem artichoke growth,development, and field storage. II. Carbon and nutrient element allocation and redistribution

Jerusalem artichokes store carbon (C) predominately in the form of inulin, a functional food of increasing interest due to its dietary health benefits for humans and calorie replacement potential in processed foods. To better understand the developmental and agronomic requirements of this crop, the allocation of C and nutrient elements into individual plant parts (stems, leaves, stolons, tubers, ‘seed’ tuber, and roots) was monitored at 2‐week intervals throughout the entire growth cycle of the cultivar ‘Sunchoke’ grown on a Cecil sandy clay loam. Accumulation patterns of C and nutrient elements in individual plant parts were generally in accordance to the pattern of dry matter accumulation, though concentration patterns differed. Overall, nutrient element levels in vegetative structures decreased with the onset of rapid tuber development. Leaves had the highest nutrient levels, except iron (Fe) and sodium (Na). The concentrations of nitrogen (N), phosphorus (P), potassium (K), sulfur (S), and copper (Cu) in tubers were greater than in stems. Total N, P, and K concentrations in the stolons were at lower levels and the total calcium (Ca), Fe, and manganese (Mn) at higher levels compared to the tubers. During rapid tuber growth, the concentration of individual phloem‐mobile nutrient elements (e.g., N, P, and K) in the leaves and stems decreased progressively due in part to reallocation. In contrast, the concentration of less mobile nutrient elements (e.g., Ca and Mn) in the leaves and stems generally increased due to losses of C and other mobile materials. In the tubers, the concentration of C and most nutrient elements remained fairly constant through the final harvest, indicating carbohydrates and nutrient elements were accumulating at the same rate. Knowledge of C and nutrient element allocation/ reallocation in the Jerusalem artichoke is of value for improving fertilization strategies and in identifying critical traits for the selection of new, high yielding cultivars.     

氮肥对菊芋生物量、 热值和灰分含量的影响

探讨氮肥对菊芋生物量、热值和灰分含量的影响,为菊芋氮肥管理提供理论参考。于2010年在内蒙古锡林河流域利用弃耕地进行菊芋种植,设置0、2.5、5、7.5、10 g/m2 5个施氮水平,对不同施氮水平条件下菊芋的生物量、热值和灰分进行测定。结果表明:氮肥施入能够提高菊芋生物量、能量积累量和热值,最佳施氮量5～7.5 g/m2;各器官热值顺序为根系＞茎秆＞块茎＞叶片;能量积累量顺序为块茎＞茎秆＞叶片＞根系;灰分含量顺序为叶片＞茎秆＞根系＞块茎。     

菊芋氮磷钾吸收积累与分配特征研究

以“青芋1号”菊芋为试材,通过田间试验对菊芋全生育期的各器官内氮、磷、钾养分的吸收积累与分配特征进行了研究。结果表明,随生育期的延长菊芋各器官营养元素浓度呈下降趋势。营养元素吸收速率呈双峰曲线变化;营养元素积累总量表现为:氮钾磷。块茎形成前,营养元素主要存于茎、叶;块茎形成到块茎膨大始期,叶内营养元素分配量持续减少,块茎分配量持续增多,而茎内磷、钾则呈单峰曲线变化;块茎开始膨大后,营养元素在茎、叶的分配量均迅速减小,块茎分配量迅速增加。     

Jerusalem artichoke growth,development, and field storage. I. Numerical assessment of plant part development and dry matter acquisition and allocation

Abstract

Expanding commercial interest in the use of inulin as a bulking agent for artificial sweeteners, dietary fiber health supplement, fat replacement for processed foods, feed stock for fructose syrups, and a wide range of potential industrial products, has stimulated research on inulin‐containing crops such as the Jerusalem artichoke. To better understand the developmental physiology of the crop and to identify potential breeding objectives, the temporal pattern of development of individual plant parts (shoots, branches, leaves, flowers, stolons, tubers, and roots) and the allocation of dry matter into the same plant parts were monitored in the cultivar ‘Sunchoke’ over the entire growing season and during in situ field storage during the early winter, 32 weeks after planting. While number of shoots (～9) peaked in week 10, the number of branches (42.8), stolons (49.4), and tubers (85.5) reached a maximum 24–28 weeks after planting. Number of leaves (～525) peaked between weeks 20–24 after planting, as did number of flowers (～55). The Jerusalem artichoke allocated the major portion of its dry matter (dm) into aboveground plant parts during the first half of the growing season. Approximately 16 weeks after planting, the pattern of allocation shifted dramatically with: a) near cessation in the acquisition of dry matter; and b) the reallocation of existing dry matter from the aboveground organs into the tubers. By the 16th week after planting, 85% of the total dm was in the aboveground plant parts, but declined to 28% by the 30th week. Of the total dm, 92% was accrued during the first 16 weeks and only 8% thereafter. The shift in dry matter resources coincided with a dramatic decrease in leaf number and in leaf and branch dry weight. By the end of the season, the harvest index reached 0.70 and the tuber yield 14.61 dm ha^?1. Yield improvement could potentially be facilitated through lengthening the logarithmic period of carbon fixation and by earlier tuber induction and development.     

氮、磷肥对杉木幼苗生物量及养分分配的影响

采用盆栽试验,研究了不同氮、 磷肥对杉木（Cunninghamia lanceolata）幼苗生物量及养分分配的影响。结果表明,供磷可促进杉木幼苗植株和各器官生物量的增加,并影响叶、 茎、 根生物量的分配比例,氮、 磷处理幼苗叶生物量占全株生物量的45% 以上, 施氮反而降低杉木叶、 茎、 根的生物量; 施氮显著增加根和叶的氮含量,而显著降低根和叶的磷含量,对茎的氮、 磷含量没有明显影响; 施磷显著降低叶、 茎、 根的氮含量,叶、 茎、 根的磷含量随供磷水平的增加而逐渐增加。氮磷配施显著影响叶、 茎、 根的氮、 磷含量和氮、 磷累积量。叶片是主要的氮、 磷养分存储器官。氮（或磷）水平的增加可降低杉木幼苗的磷（或氮）利用效率,提高氮（或磷）的利用效率; 氮、 磷肥显著影响杉木幼苗叶、 茎、 根的N/P比。研究结果说明,氮、 磷肥增加了杉木幼苗各器官生物量和氮、 磷含量,影响了幼苗的养分分配和营养平衡。     

中国沿海半干旱地区海水养殖废水灌溉耐盐植物(菊芋)的研究

An experiment with six treatments： CK1 （rainfed）, CK2 （irrigated with freshwater）, and 4 treatments of saline aquaculture effluent blended with brackish groundwater at different ratios of 1：1, 1：2, 1：3, and 1：4 （v/v） was carried out during 2004 to assess the effect of saline aquaculture effluent on plant growth and soil properties in the Laizhou region, Shandong Province, China and to determine an optimal salinity threshold for aquaculture effluent. Cumulative evapotranspiration for the saline aquaculture effluent irrigation and non-irrigation treatments was lower than that for the freshwater irrigation treatment. Soil electrical conductivity was higher with respect to saline aquaculture effluent irrigation treatment compared to that with respect to non-irrigation or freshwater irrigation treatment. For Jerusalem artichoke （Helianthus tuberosus L.）, in comparison to the freshwater treatment, plant height and aboveground biomass for the 1：3 and 1：4 treatments were constrained, whereas stem width and root biomass were enhanced. Concomitantly, higher tuber yield was obtained for the 1：3 and 1：4 treatments compared to that for CK1 and 1：1 treatments. Nitrogen and phosphorus were higher in tubers of the 1：4 treatment. This study demonstrated that saline aquaculture effluent could be used successfully to irrigate Jerusalem artichoke with higher tuber yield and nutrient removal.     

Root-zone temperature influences the distribution of Cu and Zn in potato-plant organs.

Root-zone temperatures (RZT) in relation to Cu and Zn uptake and tissue accumulation, and to total biomass, in potato plants (Solanum tuberosum L. var. Spunta) were studied. Using five different plastic mulches (no cover, transparent polyethylene, white polyethylene, coextruded white-black polyethylene, and black polyethylene) resulted in significantly different RZT (16, 20, 23, 27, and 30 degrees C, respectively). These RZT significantly influenced Cu and Zn content (concentrated) and the biomass in various potato organs. Root-zone temperature at 20 degrees C resulted in significantly high Cu content in leaflets, and soluble Cu content in leaflets and stems, whereas 23 and 27 degrees C resulted in significantly high Cu content in roots. However, RZT had no effect on Cu content in tubers or stems or on soluble Cu in roots or tubers. The RZT at 20 degrees C resulted in significantly high Zn and soluble Zn in stems, roots, and tubers; whereas, at 27 degrees C Zn and soluble Zn content were significantly highest in leaflets. The most biomass occurred in roots and tubers at 27 degrees C; whereas in leaves and stems, the RZT influence was highly variable. Total accumulation of both Cu forms was affected by RZT at 20 degrees C, with roots and tubers having significantly the least Cu and stems and leaflets having the most. Total accumulation of both Zn forms by RZT in potato organs was highly variable, but tubers consistently accumulated the most.     

Morphology,Biomass, and Vessel Diameter of Pigeon Pea Subjected to Water Stress

This research was designed to study the effects of drought on pigeon pea [Cajanus cajan (L.) Millsp.] morphology, biomass, and vessel diameter. Cultivated seeds of pigeon pea (cv. Georgia-II) were germinated, maintained in an environmental chamber, and arranged as a split-plot design with four replications; harvest was the main effect and watering regimens were tested against residual error. Plants were watered every 2, 4, 8, 16, or 32 days. Number of stems and leaves, as well as total plant height, were measured weekly. Dry weight (DW) of roots, stems, and leaves were recorded at each harvest, and root cross sections were viewed to determine vessel diameter. Results indicated that plant morphology, biomass, and vessel diameter were significantly affected by harvest and watering regimen. Plants watered more frequently had more stems and leaves, grew taller, accumulated greater DW, and had larger diameter vessels within root tissue.     

半干旱地区海涂海水灌溉对不同品系菊芋产量构成及离子分布的影响

在半干旱海涂以不同品系菊芋（Helianthus tuberosusL．）为材料进行田间试验，研究了海水灌溉对不同品系菊芋产量构成及离子分布的影响。结果表明：（1）南芋2号根和地上部生物量较其他品系大，南芋5号和南芋3号株高在各浓度海水灌溉下均显著高于其他菊芋品系，而茎粗在各处理下变化不一致，在30％海水灌溉下，南芋1号根和地上部物质积累未受到抑制作用，其他各品系菊芋的根和地上部物质积累受到了一定抑制。（2）各菊芋品系块茎产量差异较显著，在30％海水灌溉下，南芋2号产量显著高于其他品系，各菊芋品系块茎单重在各处理下差异也较显著，南芋1号和2号块茎单重最大，各菊芋品系块茎总糖和菊糖含量差异较显著。（3）随海水浓度的增加，各品系菊芋根、茎和叶的C1-和Na^＋含量均增加，但品系间差异较显著，叶片的Na’含量显著低于根和茎的Na’含量。从生物积累量和块茎产量、总糖和菊糖含量及离子分布看，南芋1号和南芋2号较其他品系更适合在半干旱海涂利用适当浓度海水进行灌溉种植。     

镉在两种菊芋品种中的吸收与转移特性研究

Jerusalem artichoke(Helianthus tuberosus L.) not just can be used for bioethanol production but may be potentially used in phytoremediation for the removal of heavy metal pollutants.Two Jerusalem artichoke cultivars,N2 and N5,were subjected to six cadmium(Cd) concentrations(0,5,25,50,100 and 200 mg L1) to investigate Cd tolerance and accumulation.After 21 days of growth,the effects of Cd on growth,chlorophyll content,net photosynthetic rate,intercellular CO2 concentration and malondialdehyde content were evaluated.Most growth parameters were reduced under Cd stress.The two Jerusalem artichoke cultivars had relatively high Cd tolerance and accumulation capacity(> 100 mg kg1),with N5 being more tolerant and having higher Cd accumulation than N2.Roots accumulated more Cd than stems and leaves.The bioconcentration factors(far higher than 1) and translocation factors(lower than 1) decreased with an increase in Cd applied.The results suggested that Jerusalem artichoke could be grown at relatively high Cd loads,and N5 could be an excellent candidate for phytoremediation of Cd-contaminated soils.     

Variations in morphological and agronomic traits among Jerusalem artichoke (Helianthus tuberosus L.) accessions

Jerusalem artichoke is a diversely-utilized crop. Selection for high yield, inulin content and other economically important traits are useful for improving this crop. The objectives of the present study were to evaluate genetic variability for qualitative and quantitative traits among Jerusalem artichoke accessions and to identify different groups of accessions using morphological and agronomic traits. Seventy-nine accessions were evaluated in a randomized complete block design with two replications in the late rainy season 2008, the early rainy season 2009 and the late rainy season 2009 at Khon Kaen University agronomy farm, Thailand. Morphological and agronomic characteristics were evaluated for genetic variations. High variations were found among Jerusalem artichoke accessions for qualitative and quantitative characters, and selection for these characters is possible. High variations were observed for tuber width, number of tubers/plant, biomass, fresh tuber yield and tuber size. Correlation coefficient between fresh tuber yield and tuber size was positive and significant (0.58, P ≤ 0.01). Improvement of tuber size is a means to improve yield and tuber quality. Based on morphological and agronomic characteristics, Jerusalem artichoke accessions were clustered into four distinct groups (R² = 0.88). These groups may be used as parental material to generate progenies for further improvement of this crop. This information will enable breeders to make informed decisions about possible heterotic groups for their breeding programs and germplasm conservation.     

华北平原海水灌溉对土壤性质和菊芋产量的影响

Irrigation with various dilutions of seawater can act as an alternate water resource and thus plays an important role in saving freshwater resources as well as promoting agriculture in the coastal semi-arid areas of the North China Plain. Jerusalem artichoke （Helianthus tuberosus L.） grown in a field experiment was irrigated with seawater diluted with freshwater from 2001 to 2003 to determine the feasibility of seawater irrigation in the Laizhou area. For treatments of CK （non-irrigation） along with seawater concentrations of 25%, 50%, and 75%, total dissolved solid （TDS） in the non-irrigated soil significantly increased （P ≤ 0.05） in both 2002 and 2003 and was 1.3 times higher in 2003 than in 2001. In the 25% and 50% seawater concentration treatments, TDS in 2001 was significantly greater （P ≤ 0.05） than CK; however, TDS in these two treatments decreased by 34.9% and 40.1%, respectively, in 2003 compared with 2001. The sodium adsorption ratio （SAR） remained below 10 mmol^1/2 L^-1/2, indicating that alkalization was low with seawater irrigation. In 2001 and 2002, compared to CK and the irrigation treatment with 75% seawater, irrigation with 25% and 50% seawater increased the yields of Jerusalem .artichoke. This meant that Jerusalem artichoke could be safely grown in salt-affected land of Laizhou area with 25% and 50% seawater irrigation.     

糖醇螯合钙肥对马铃薯产量、品质及养分吸收的影响

采用恒温水浴加热的方法合成糖醇螯合钙(自制钙肥),与美国布兰特公司生产的糖醇螯合钙(市售钙肥)同时进行马铃薯大田喷施试验,研究糖醇钙对马铃薯产量、品质和钙素吸收、迁移转化的影响。研究结果表明:①与不施钙肥(喷施等量清水)相比,自制钙肥与市售钙肥处理分别增产10.9%和12.1%,大薯率分别提高5.4%和3.7%,两种钙肥处理均降低了中、小薯率;自制钙肥与市售钙肥处理块茎硝态氮含量分别下降28.8%和31.6%,自制钙肥处理马铃薯的可溶性蛋白的含量和氮素积累量分别增加7.2%和20.9%,市售糖醇钙处理马铃薯的可溶性蛋白含量和氮素积累量均降低3.2%。②钙肥处理均提高了马铃薯各器官的钙素含量,在出苗后80 d,自制钙肥与市售钙肥处理的马铃薯根中钙含量分别增加8.0%和9.0%,茎中钙含量分别增加10.1%和6.8%,叶片中钙含量分别增加1.8%和6.8%,块茎中钙含量分别增加26.7%和20.0%。③施用钙肥均提高了马铃薯各器官与全株的钙素累积量,自制钙肥与市售钙肥处理的马铃薯根中钙素累积量均提高20.0%,茎中钙素积累量分别提升97.1%和55.7%,叶片中钙素积累量分别提升56.5%和45.8%,块茎中钙素积累量分别提高56.3%和50.0%,全株钙素积累量整体提高62.1%和47.0%。自制钙肥处理的马铃薯根、茎、块茎和全株的钙素累积量均显著高于市售钙肥。综上,在同等钙浓度下,两种钙肥均促进了马铃薯产量提升,与市售钙肥相比自制螯合钙肥更利于钙素的吸收和迁移。     

Effect of seasonal changes on content and profile of soluble carbohydrates in tubers of different varieties of Jerusalem artichoke (Helianthus tuberosus L.)

A high content (60-65% of dry mass DM) of water soluble carbohydrates was found in early harvested varieties (Bella and Bianka) and middle early varieties (Topstar and Gigant) harvested 22-25 weeks after plantation. In late varieties (Waldspindel, Violet de Rennes, Rote Zonenkugel) a similar amount was obtained (55-60% of DM) when harvested 29-33 weeks after planting. There was a distinctive impact on maturing process as well as frost period alterations which resulted in conversion of high polymer inulin to low polymer inulin as well as to sucrose. In early/middle early varieties a correlation between sucrose and inulin level (r = - 0.952**) with a linear regression of y = - 1.35x + 62.32 was observed, whereas the dpn of inulin decreased from 12-14 to 6-8. In late cultivars this correlation was not as exact (r = - 0.502**); dpn of inulin decreased from 12-16 to 7-10. This knowledge about carbohydrate profiles for different varieties of Jerusalem artichoke offers the possibility of selecting suitable cultivars and deciding the appropriate harvest time for an optimum processing of tubers for their application as prebiotic and novel food component.     

亏缺灌溉对马铃薯生长产量及水分利用的影响

为了解析马铃薯不同品种对水分亏缺的响应,探讨不同品种对水分需求量的差异,该研究在大田遮雨棚滴灌下,以马铃薯品种‘青薯9号’和‘大西洋’为材料,参考西北区和本试验区的年平均降雨量,设置5个水分处理,将参考试验区年平均降雨量的值划分为正常灌水(A),逐级调亏灌水量的值划分为轻度(B)、中度(C)、重度(D)和特重度(E)亏缺灌水处理,研究灌水量对不同品种马铃薯植株生长(株高、茎粗、叶面积)、生物量与分配、叶片相对含水量、产量与构成因素、水分利用的影响。结果表明:正常灌水下,‘青薯9号’株高增长速度大于‘大西洋’,且测定期内持续增高,但‘大西洋’叶面积快速扩增期的扩增速度大于‘青薯9号’;2个品种各器官干质量变化趋势不一致,‘大西洋’各器官干质量呈增长趋势,‘青薯9号’茎叶和根干质量呈前期增长后期下降、块茎干质量呈显著增加趋势(P0.05),且‘青薯9号’块茎生物量分配比例最高值为57.96%,仅是‘大西洋’最高值的67.43%;2个品种叶片相对含水量均呈先升高后降低的变化趋势;‘大西洋’单株结薯数、单株产量、公顷产量、商品薯率高于或显著高于亏缺灌溉(P0.05),‘青薯9号’仅商品薯率和大薯率高于或显著高于亏缺灌溉(P0.05),其他指标则显著低于轻度亏缺灌溉(P0.05),水分利用效率和灌水效率分别为152.62kg/(hm~2·mm)和130.70%。亏缺灌溉下,随水分亏缺度加重,‘大西洋’株高、茎粗和叶面积扩增的抑制大于‘青薯9号’,2个品种叶片相对含水量降低、生物量积累的增速和绝对值降低、产量和大薯率显著下降(P0.05),且‘青薯9号’上述指标的降幅小于‘大西洋’,其中轻度亏缺灌溉下,‘青薯9号’单株结薯数和公顷产量具有补偿效应,较正常灌水分别增加22.79%和11.71%,水分利用效率提高41.48%、灌水效率提高60.05%,抗旱系数为1.12。因此,‘青薯9号’轻度亏缺灌溉,可控制其地上部旺盛生长,利于块茎形成和膨大,‘大西洋’应保证充足水分供给,不宜亏缺灌溉。     

深松耕对玉米根茎叶氮磷比及地上生物量的影响

植物器官氮磷比可以揭示植物生长发育过程的营养平衡。深松耕作为黄土高原半干旱区一种较好的农田耕作方法被广泛应用,尽管已被证实深松耕可以提高作物产量和地上生物量,但深松耕是否影响作物器官N/P及从作物器官N/P角度能否解释地上生物量增加的机制尚有待进一步研究。该研究于2016－2018年在黄土高原区设置了不同耕作方法（深松耕、旋耕、翻耕和免耕）和施氮量（基肥200 kg/hm2、基肥200 kg/hm2+拔节期肥100 kg/hm2）的田间裂区试验,研究了不同处理对玉米地上生物量、不同器官（根、茎和叶）中N/P的影响以及其N/P与地上生物量的关系。结果表明：1）相比翻耕、免耕,深松耕能显著提高地上生物量（P<0.05）,2016和2018年地上生物量深松耕比翻耕、免耕分别提高了9.56%、9.29%和4.67%、5.94%;2）相比翻耕、免耕,深松耕和旋耕均能显著降低根、叶的N/P（P<0.05）,深松耕根、叶N/P分别为19.90、17.74,降幅最大;施肥措施及耕作方法与施肥措施的交互作用对根、茎和叶的N/P无显著影响;3）通过结构方程模型分析发现,耕作方法通过影响根和叶N/P,间接影响地上生物量,效应值分别为0.10和0.14,耕作方法对地上生物量无直接显著影响,说明了根和叶的N/P是影响地上生物量的两种重要的间接因素;通过线性混合效应模型分析得出,地上生物量与根、叶N/P呈显著负相关关系,与茎N/P无相关性。研究表明深松耕通过降低玉米根和叶N/P,促进植物氮磷营养平衡的生态策略来提高地上生物量。研究结果对进一步揭示耕作与施肥对玉米生产与农田生态系统氮磷平衡的影响机制具有一定的借鉴意义。     

再生水灌溉不同滴头布置方式下PPCPs在土壤和番茄中的累积

随着药品和个人护理品(Pharmaceuticals and Personal Care Products,PPCPs)生产和使用量的增加,PPCPs及其代谢产物在再生水中的检出种类、检出量不断增多,再生水灌溉可影响PPCPs在土壤-作物(蔬菜)系统中的分布及累积,但其规律及驱动机制尚不明确。为探明再生水滴灌条件下滴头布置方式对PPCPs在土壤-作物(蔬菜)系统累积的影响,该研究采用盆栽试验比较2种滴头布置方式(在番茄根部、在两番茄中间)对土壤剖面及番茄各器官中PPCPs累积量的影响,并进一步分析PPCPs在土壤-作物(蔬菜)系统累积的驱动机制。结果表明,再生水灌溉条件下不同滴头布置方式造成了PPCPs在土壤、作物(蔬菜)中累积规律的差异性,滴头布置在两番茄中间处理较其他处理而言增加了0～5cm土层吉非罗齐累积量(P0.05),降低了番茄叶部卡马西平和根部吉非罗齐的累积量(P0.05),较滴头布置在番茄根部处理降低了番茄叶部吉非罗齐和根部三氯生的累积量(P0.05);不同再生水灌溉方式通过影响土壤微环境指标导致了土壤中PPCPs分布规律的差异性,滴头布置在植株中间处理较其他处理增加了0～5 cm土层pH值,导致该土层下吉非罗齐的累积量高于其他处理(P0.05)。研究可为基于新兴污染物PPCPs防控的再生水农业安全利用提供理论依据。     

养殖废水灌溉下施用生物质炭和果胶对土壤养分和重金属迁移的影响

【目的】 养殖废水中含有丰富的养分,但也含有一定的重金属。本文研究了生物质炭和果胶对养殖废水灌溉下的土壤–植物系统养分和重金属迁移规律的影响,以利用养殖废水中的养分,并对其重金属进行调控。 【方法】 选取新乡市郊区农田土壤为供试土壤,采用根箱试验方法种植玉米。设置根箱土壤中添加1%的生物质炭和果胶,分别灌溉蒸馏水和养殖废水发酵产生的沼液。测定了土壤中养分和重金属的含量,探讨了其在土壤–植物系统的迁移规律。 【结果】 沼液灌溉的植株地上部生长与蒸馏水灌溉无显著差异。果胶相比于生物质炭可以促进植株生长。沼液灌溉时,果胶处理的根系和地上部生物量分别比对照增加了25.38%和31.21%。沼液灌溉普遍降低了根际和非根际土壤的pH,生物质炭处理和果胶处理与对照根际和非根际土壤的pH均无显著差异。沼液灌溉增加了非根际土壤的电导,生物质炭相比于果胶增加了土壤的电导。沼液灌溉增加了土壤全氮、有效磷、速效钾和有机质含量。果胶根际土壤的全磷、碱解氮、有效磷、有效Fe、有效Mn均高于生物质炭处理,生物质炭处理根际和非根际土壤的全钾和速效钾含量均高于果胶处理。沼液灌溉相比于蒸馏水灌溉,增加了植株根、茎中N含量和Ca含量。生物质炭处理植株根茎叶N含量、根茎P含量、茎K含量、根茎叶Ca含量、根茎Mg含量高于果胶处理,但果胶处理养分的转运系数较高。养殖废水灌溉增加了根际和非根际土壤中有效Cu和Zn尤其是Zn的含量。与对照相比,生物质炭降低了根际土壤Cu、Pb、Ni的含量,而果胶增加了它们的含量。沼液灌溉增加了植株根茎叶中Cu、Zn、Pb含量,果胶处理植株根系Cu、Zn、Pb、Cd、Ni含量最高,但向地上部转运较少。 【结论】 在北方碱性土壤灌溉养殖废水发酵产生的沼液时,施用生物质炭和果胶可以提高土壤肥力和植株养分含量,生物质炭通过减少土壤中有效态重金属含量以减少重金属在植物体内累积,果胶虽然增加土壤有效态重金属含量,但可以降低其向地上部的转运,避免了重金属在植物体内的累积。      

海水养殖废水灌溉条件下SPAC系统中水盐肥通量研究

2004年4月～10月，在半湿润的莱州地区布置蒸渗试验，研究海水养殖废水灌溉条件下SPAC系统水盐肥通量。试验设5个处理，分别为CK（种作物，不灌溉）和淋洗分额（LF）为0．1、0．2、0．3、0．4的海水养殖废水灌溉处理。结果表明：对于淋洗分额为0．1、0．2、0．3、0．4的海水灌溉处理，用于土壤蒸发和作物蒸腾的海水养殖废水量分别占菊芋生育期总蒸散量的36．5％、36．2％、37．0％、37．3％；对于上述海水养殖废水灌溉处理，土壤耕层的盐分积累量分别为91．1、94．1、98．7、107．1g；而铵态氮的积累量分别为2．00、2．29、2．27、2．82mg，硝态氮的积累量分别为1．81、1．40、1．29、0．92mg，活性磷酸盐的积累量分别为3．03、2．68、2．44、1.67mg。因此，认为海水养殖废水灌溉在供给作物水分和养分方面起到积极作用，但需采取调控措施以防耕层土壤盐分过量积累。     

钼对甘蔗体内固氮菌的固氮酶活性的影响

以巴西固氮甘蔗品种B1和B8为材料,在温室桶栽砂培条件下,对甘蔗施以含不同钼水平的营养液,以了解钼对甘蔗体内固氮菌的固氮酶活性的效应。结果表明,在含氮条件下,较低浓度的钼处理能提高甘蔗根内固氮菌的固氮酶活性,高浓度钼处理则能提高B1茎、叶片和B8茎中固氮菌的固氮酶活性;在无氮条件下,钼处理提高了B1叶片和茎中固氮菌的固氮酶活性,而B1根及B8根、茎、叶中固氮菌的固氮酶活性有所降低。此外,甘蔗根、茎、叶中固氮菌的固氮酶活性之间关系较为密切,根中固氮菌的固氮酶活性与叶片和茎中的都呈负相关。上述结果说明:巴西甘蔗在本地也具有一定的固氮能力;在不缺氮条件下,钼处理较利于调节甘蔗体内固氮菌的固氮酶活性,促进其固氮;而在缺氮条件下,钼处理不利于调节甘蔗体内固氮菌的固氮酶活性,抑制其固氮作用。