Avocado rootstock influences scion leaf mineral content

ABSTRACT

To test the influence of avocado rootstocks on the scion leaf ionome, the nutritional status of avocado cultivars Hass and Ettinger grafted onto 15 rootstocks was compared over 3 years. The rootstocks were of different genetic origins (West Indian or Mexican) and were clonally or reproductively propagated. The trees were grown in a high-density orchard, and were continually fertigated as is common in modern avocado orchards. Leaf mineral composition was analysed and found to be correlated with crop load. ‘Hass’ leaves had significantly higher levels of B, Ca, Mg, Na, P and K than ‘Ettinger’ leaves. Rootstocks of Mexican origin produced higher foliar Cl levels, but lower levels of Mg and Mn. Rootstocks grown from seedlings conferred higher foliar K and lower B, Ca and Mg. The results demonstrate that avocado rootstocks affect the nutritional status of the tree, by a differential mineral transport, which is indicated by the scion leaf ionome.     

Salt tolerance of two lemon scions measured by leaf chloride and sodium accumulation

Effects of salinity on growth, ion content, water relationships, and chlorophyll and proline levels were measured on one‐year‐old ‘Verna’ and ‘Fino’ lemon (Citrus limon [L] Burm. F.) scions budded to either Sour orange (C. aurantium L.) or macrophylla (C. macrophylla Wester) rootstock. Trees were grown in nutrient solutions containing 2 (control), 40, or 80 mol m^‐3 NaCl for 75 days.

Growth of all combinations was reduced by salinity, but this effect was greater for both scions budded on macrophylla. Leaf chloride and sodium concentrations were lower in both scions budded on Sour orange. Leaf salt concentration was scion dependent. Leaves of ‘Fino’ lemon had higher levels of both chloride and sodium than did leaves of ‘Verna’ lemon, regardless of the rootstock considered.

Despite an accumulation of chloride and sodium in the leaves of salinized trees, leaf water potential and leaf water content increased above the control level. However, stomatal conductance declined in all rootstock/scion combinations.

Chlorophyll contents were markedly reduced by salt treatment; greater reductions were seen in ‘Fino’ lemon than in ‘Verna’ lemon on both rootstocks. Chlorophyll reductions were highly correlated with both chloride and sodium concentrations in the leaves. Free proline increased with salinity in leaves of both scions budded on Sour orange, but was unaffected on macrophylla.

Differences in the parameters determined in response to salinity were attributed to the different capacity of each specific rootstock/scion combination to import chloride and sodium into leaves.     

Changes in soil aggregation and glomalin-related soil protein content as affected by the arbuscular mycorrhizal fungal species Glomus mosseae and Glomus intraradices

Arbuscular mycorrhizal (AM) fungi are key organisms of the soil/plant system, influencing soil fertility and plant nutrition, and contributing to soil aggregation and soil structure stability by the combined action of extraradical hyphae and of an insoluble, hydrophobic proteinaceous substance named glomalin-related soil protein (GRSP). Since the GRSP extraction procedures have recently revealed problems related to co-extracting substances, the relationship between GRSP and AM fungi still remains to be verified. In this work the hypothesis that GRSP concentration is positively correlated with the occurrence of AM fungi was tested by using Medicago sativa plants inoculated with different isolates of Glomus mosseae and Glomus intraradices in a microcosm experiment. Our results show that (i) mycorrhizal establishment produced an increase in GRSP concentration - compared to initial values - in contrast with non-mycorrhizal plants, which did not produce any change; (ii) aggregate stability, evaluated as mean weight diameter (MWD) of macroaggregates of 1-2 mm diameter, was significantly higher in mycorrhizal soils compared to non-mycorrhizal soil; (iii) GRSP concentration and soil aggregate stability were positively correlated with mycorrhizal root volume and weakly correlated with total root volume; (iv) MWD values of soil aggregates were positively correlated with values of total hyphal length and hyphal density of the AM fungi utilized.The different ability of AM fungal isolates to affect GRSP concentration and to form extensive and dense mycelial networks, which may directly affect soil aggregates stability by hyphal enmeshment of soil particles, suggests the possibility of selecting the most efficient isolates to be utilized for soil quality improvement and land restoration programs.     

INFLUENCE OF ROOTSTOCK ON MINERAL UPTAKE AND SCION GROWTH OF ‘GOLDEN DELICIOUS’ AND ‘ROYAL GALA’ APPLES

Influence of four rootstocks (M.9, MM.106, MM.111, and local seedling) on the scion leaf and fruit mineral concentrations, tree growth, yield and fruit quality attributes of ‘Golden Delicious’ and ‘Royal Gala’ apples during four seasons (2008–2011) were significant. The mechanisms behind the influence of rootstock on scion vigor and yield was that the rootstock brought about its effects upon the scion by influencing the amounts of minerals taken up and translocated to the scion. ‘Royal Gala’ and ‘Golden Delicious’ trees on seedling had the highest efficiency in calcium (Ca) and potassium (K) uptake. Whereas, trees of these cultivars on M.9 were more efficient in nitrogen (N), manganese (Mn) and iron (Fe) uptake. MM.106 had the highest efficiency in phosphorous (P) uptake, and M.9 had the lowest K and Ca uptake. The highest N- fruit concentration and the lowest Ca-fruit concentration were observed in cultivars on M.9.     

盐碱胁迫对黄瓜嫁接苗根际土壤细菌和真菌群落结构及丰度的影响

为了解盐碱胁迫对黄瓜嫁接苗根际土壤细菌和真菌群落结构的影响,本研究以2种耐盐碱砧木‘华砧108’(T1)、‘神力铁木砧’(T2)和2种盐碱敏感砧木‘辉太郎’(S1)、‘京欣砧6号’(S2)为试材,自根苗作为对照,以混合盐(盐分摩尔比为NaHCO_3∶Na_2SO_4∶NaCl∶Na_2CO_3=4∶2∶2∶0.15)浓度为100 mmol·L~(-1)、pH 9.0的处理液处理20 d、30 d、40 d(定植30 d、40 d、50 d),利用PCR-DGGE技术,研究了盐碱胁迫对不同砧木嫁接的黄瓜幼苗根际土壤微生物群落结构和丰度的影响。结果表明,耐盐碱的砧木品种T1、T2根际土壤真菌DGGE图谱条带数显著高于盐碱敏感的S2和自根苗对照CK,并且耐盐碱的品种T2土壤细菌的Shannon-Wiener指数与均匀度指数均显著高于盐碱敏感的品种S1、S2和自根苗对照CK。耐盐碱品种T1的细菌16S rDNA基因拷贝数在定植50 d时显著高于盐碱敏感的品种及自根苗;在定植40 d时,耐盐碱的砧木T2真菌ITS基因拷贝数显著高于盐碱敏感的品种以及黄瓜自根苗;定植50 d时,耐盐碱的砧木真菌ITS基因拷贝数显著高于盐碱敏感的品种,但与自根苗差异不显著。不同耐盐碱性砧木嫁接黄瓜幼苗根际土壤微生物群落结构组成和丰度存在差异。以上研究表明,随着盐碱胁迫时间的增加,耐盐碱性不同的砧木嫁接苗根际土壤微生物群落丰度与结构多样性产生了较大差异,间接改变了土壤微生态环境,致使土壤微生物数量和丰富度也发生改变。耐盐碱的砧木品种可能通过改善土壤微环境来加强其自身的耐盐碱特性。     

Response of Young Citrus Trees on Selected Rootstocks to Nitrogen,Phosphorus, and Potassium Fertilization

The majority of the citriculture in Brazil is located in the state of São Paulo, with a total production area of 700,000 ha. Trees are grafted mostly on ‘Rangpur’ lime (RL; Citrus limonia Osbeck) rootstock. Despite its good horticultural performance, use of other rootstocks has increased with the search for disease-tolerant varieties to improve grove productivity and longevity. Furthermore, there is a lack of information on young tree response to fertilization, and optimal nutrient requirements of different scion/rootstock combinations for maximum fruit yield. A network of field experiments was conducted to study the differential response of young sweet orange trees on selected rootstocks to nitrogen (N), phosphorus (P), and potassium (K) fertilization. The application of soil and leaf analyses to develop optimal fertilizer recommendations was evaluated. Experiments were conducted in three locations using fractional factorial design of one-half (4 × 4 × 4) type with four rates of N, P, or K calculated to be applied for five years after tree planting. Fruit yield response was evaluated during the last two years and correlated with soil and leaf analyses data. The trees on RL rootstock demonstrated increased efficiency of nutrient use and fruit production compared with those on ‘Cleopatra’ mandarin (CL; C. reshni hort. ex Tanaka) or ‘Swingle’ citrumelo [SW; Poncirus trifoliata (L.) Raf. × C. × paradisi Macfad.] rootstocks. The trees on SW rootstock appeared to require greater N and K rates than those on RL rootstock. Phosphorus requirement was greater for ‘Natal’ or ‘Valencia’ trees on CL than on RL rootstock. These results will become the basis for revising current fertilizer recommendation guidelines for young trees in Brazil.     

黄蒿和大籽蒿与两个园林小菊砧穗组合对生长和开花的影响

为了探究黄蒿(Artemisia annua)和大籽蒿(Artemisia sieversianae)作为砧木嫁接菊花的效果,拓展菊花嫁接的砧穗组合,本研究以园林小菊钟山粉韵和钟山紫辰为接穗,黄蒿和大籽蒿为砧木,比较4种砧穗组合嫁接对嫁接株的成活和发病、生长特性(冠幅、冠丛周径、砧木茎粗、最大根长、接穗干重、根干重、总...     

Rootstock Effect on Nutrient Concentration of Sweet Cherry Leaves

The present investigation aimed to study the leaf mineral composition of sweet cherry trees on different rootstocks, since the literature data on uptake efficiency of different rootstocks is inconsistent. Results confirmed the different uptake efficiency of rootstocks. The efficiency of ‘GiSelA 6’ root is emphasized in uptake and supply of leaves with nitrogen (N), phosphorus (P), potassium (K), zinc (Zn), boron (B), and manganese (Mn), but trees on this rootstock tend to develop calcium (Ca), magnesium (Mg), and copper (Cu) deficiencies. The Prunus mahaleb rootstocks on calcareous sandy soil are efficient supplier of N, P, K, Ca, Mg, Fe, and Cu, but this root tends to develop Zn, B, and Mn deficiencies. Prunus avium seedling as rootstock proved to be less efficient in supply of leaves by N, P, K, Ca, and Cu. Prunus fruticosa ‘Prob’ root showed tendency in developing several leaf nutrient deficiencies. The applied fertilizer program led to low nutrient levels or even deficiency symptoms in leaves.     

露地小型西瓜产量品质砧木效应的综合评价

为综合评价露地小型西瓜产量品质的砧木效应,以接穗京颖-6自根苗为对照,研究南瓜砧和葫芦砧分别嫁接同一接穗品种后,不同嫁接组合的幼苗质量、植株长势、产量、果实性状和品质变异特征。结果表明,所有砧木的嫁接成活率均高于90%,供试南瓜砧中幼苗质量以兴盛和铁砧尔帝较好,葫芦砧以强根和京欣砧1号表现较好。嫁接成株长势和产量也因选择砧木不同而表现不同,其中南瓜砧嫁接植株长势较强,产量较高,最低增产率也达17.0%;葫芦砧嫁接植株长势和产量变异较大,强根增产率达49.4%,但京欣砧王单位产量较对照低12.3%,且嫁接对小型西瓜果实特性及果实营养品质的影响显著。构成小型西瓜果实品质相关指标的综合评价结果表明,仅2个南瓜砧和4个葫芦砧嫁接果实品质优于自根苗。综上,供试南瓜砧均显著提高了小型西瓜的产量,但多降低了果实品质;葫芦砧中仅强砧和京欣砧1号嫁接西瓜的产量有所提高,且果实品质有所改善。本研究为嫁接小型西瓜优质高产栽培提供了理论依据。     

Tomato and eggplant scions influence the effect of rootstock under Na2SO4 salinity

A short-term experiment was conducted to investigate whether the effect of rootstock on plant response to salinity depends on the solanaceous species used as scion. Tomato cv. ‘Ikram’ and eggplant cv. ‘Black Bell’ were grafted onto two tomato interspecific hybrids (‘Beaufort’ and ‘He-Man’). Plants were grown in an open soilless cultivation system and supplied with two nutrient solutions: non-saline control and a saline solution (adding 15 mM Na₂SO₄, 3.7 dS m^?1). Plant dry biomass production and partitioning were influenced by salinity, but its effect was depending on the rootstock/scion combination. ‘Beaufort’ eliminated the deleterious effect of salinity when tomato was used as scion, but reduced (?29.6%) the shoot biomass of eggplant. ‘He-Man’ had a different effect on scion growth under saline conditions: shoot biomass was less reduced in eggplant (?20.6%) than in tomato (?26.8%). Under salt stress, ‘Beaufort’ reduced the accumulation of Na⁺ in tomato leaves more than in eggplant, whereas no differences were observed between tomato and eggplant grafted onto ‘He-Man’. Stem Na⁺ accumulation followed a different pattern. The increase of Na⁺ in the stems was similar for tomato and eggplant grafted onto ‘Beaufort’, whereas stems of tomato accumulated more Na⁺ compared to eggplant grafted onto ‘He-Man’. The opposite response of the tested rootstocks to salt stress when the scion was either tomato or eggplant seems to be partially related to the capacity of the rootstock and scion to exclude Na⁺ from the shoot. However, the results of nutrient accumulation within plant tissues imply that other mechanisms in addition to ion competition are involved in the salt resistance of grafted plants.     

Effect of arbuscular mycorrhizal fungi on rhizosphere organic acid content and microbial activity of trifoliate orange under different low P conditions

ABSTRACT

Arbuscular mycorrhizal (AM) fungi can improve plant phosphorus (P) uptake; however, information about how AM fungi affect rhizosphere organic acid and microbial activity to alleviate citrus low P stress is limited. Here, a pot experiment was conducted to evaluate the effect of AM fungi (Rhizophagus intraradices, Ri) inoculation on rhizosphere organic acid content, microbial biomass (MB) and enzyme activity of trifoliate orange (Poncirus trifoliata L. Raf.) seedlings grown under three low P conditions. The results showed that mycorrhizal seedlings all recorded higher P concentrations, plant biomass and better root morphology with more lateral and fine roots, but lower root mass ratios, irrespective of P conditions. Mycorrhizal P absorption contribution did not differ significantly among three P conditions. Mycorrhizal seedling rhizosphere soil exhibited lower organic acid content, soil organic P content and ratio of MB-carbon (C)/MB-P, but higher MB and enzyme activity. Additionally, the main organic acids showed a negative relationship with mycorrhizal colonization rate and hyphal length; however, phosphatase and phytase activity had a significantly positive relationship with MB. Therefore, the results suggest that AM fungi inoculation may help citrus to efficiently utilize organic P source by improving microbial activity under low available P conditions.     

Interstock effects on growth,photosynthesis and mineral nutrition of ‘delicious’ apple seedlings

Tree growth, photosynthesis, and the mineral nutrient content were investigated in ‘Redchief Delicious’ scions double worked on seedling rootstock with a variety of interstocks. The interstocks used were ‘Redchief Delicious’, M9, and a range of F. generation hybrids with internodes designated short, medium and long. The long internode graft union consistently produced more growth and dry weight per tree than the other interstocks. The ‘Redchief Delicious’ interstock had an unexplained negative effect on leaf, shoot and new root dry weight. There was no effect of interstock on photosynthesis initially (56 days) however photosynthesis increased with shorter nodal interstocks after 111 days. There were significant differences in scion and interstock bark elemental composition due to interstock combination. However, leaf composition varied slightly among the different interstock combinations. Manganese levels, independent of tissue type, did not vary between interstocks.     

EFFECT OF DIFFERENT ROOTSTOCKS ON GROWTH,CHLOROPHYLL A FLUORESCENCE AND MINERAL COMPOSITION OF TWO GRAFTED SCIONS OF TOMATO

Two tomato scions (cvs. ‘Raf’ and ‘Gorety’) were grafted on three different rootstocks: S. torvum, ‘Beaufort’ (Lycopersicum esculentum × Lycopersicum hirsutum) and intermediate grafting of eggplant ‘Cristal’ between tomato and S. torvum (double graft). Plants were grown in Mediterranean greenhouse conditions. The response to grafting was measured through growth parameters, F_v/F_m and leaf macronutrients analysis, and it was compared with non-grafted plants. The scions grafted on S. torvum in simple and double graft showed lower fresh and dry weight of leaves, number of commercial fruits, plant height, F_v/F_m and decreased their capacity to absorb several nutrients resulting in a lower mineral concentration in scions leaves, as a result of a thickened graft union. On the other hand, both scions showed a good response when grafted on the rootstock ‘Beaufort’, with which growth parameters, yield and photosynthetic capacity were similar to non-grafted plants.     

Bio-inoculants enhance growth,nutrient uptake,and buddability of citrus plants under protected nursery conditions

ABSTRACT

Bio-inoculants have been used for enhancing plant growth in horticultural crops even in nutrient-limited soils. The present research evaluated the effect of inoculation of two growing media with six biofertilizer consortia on the growth and buddability of ‘Rough lemon’ rootstock subsequently budded with ‘Kinnow’ mandarin variety. Soil + FYM + Cocopeat (SFC) with Azospirillum (Azo) + AM fungi consortium improved seed germination, seedling growth, chlorophyll, P, K, root growth, root epidermis, and cortical region thickness; xylem and phloem diameter in rough lemon; budding success and growth in Kinnow mandarin saplings. It also increased OC, P, and K levels in growing media. AM spore count and AM root colonization showed a positive correlation with budding success, root P and soil P content. SFC fortified with Azo + AM fungi resulted in better growth and buddability of rough lemon seedlings along with better growth of Kinnow mandarin saplings.     

沿海拔梯度分布的柑橘园中土壤肥力因子与丛枝菌根共生体的关系

Arbuscular mycorrhizal(AM) symbionts are able to greatly affect soil fertility. However, the relationships between AM symbiosis development levels and citrus mycorrhizosphere soil fertility remain weakly known in field. In our study, AM colonization, spore density, hyphal length density, and glomalin-related soil protein(GRSP) content in citrus(Robertson naval orange grafted on Citrus reticulata Blanco) orchards along an altitudinal gradient were investigated seasonally in southern China. The results showed that AM colonization and abundances of spore and hyphae fluctuated significantly in different seasons and altitudes. The highest AM colonization(83.03%) was observed in orchards at 200 m above sea level in summer, spore density(16.8 spores g-1soil) in orchards at 400 m in autumn, and hyphal length density(2.36 m g-1soil) in orchards at 600 m orchards in summer; while the lowest values(43.60%, 2.7 spores g-1soil and 0.52 m g-1soil of AM colonization, spore density, and hyphal length density, respectively) were all observed in orchards at 800 m in winter. Correlation analyses demonstrated that the soil properties such as soil organic matter,alkali-hydrolyzable N, available P, and p H were significantly(P < 0.05) positively correlated with either citrus total AM colonization or the abundances of spore and hyphae. GRSP was significantly(P < 0.05) positively correlated with soil organic matter and p H.Redundancy analysis supported that soil environmental factors such as altitude, GRSP, soil organic matter, and alkali-hydrolyzable N severely(Monte Carlo permutation tests, P = 0.002) influenced AM colonization and abundances of spore and hyphae in citrus orchards. Our data demonstrated that soil environmental factors are vital in determining AM symbiosis development in citrus orchards.     

Leaf mineral nutrition and tree vigor of ‘Subirana’ flat peach cultivar grafted on different Prunus rootstocks in a warm Mediterranean area

Abstract

Recent trends in peach orchards have focused on intensification and high density plantings using different Prunus rootstock species with different vigor traits. This investigation aims to study the physiological behavior of different Prunus rootstocks in order to identify the most suitable rootstock under warm Mediterranean conditions. Field agronomic performance and foliar nutrient content of the flat peach cultivar ‘Subirana’ grafted on ten different Prunus rootstocks were studied on calcareous soil typical of the Mediterranean area. Ten rootstocks: ‘ADAGAF 04-03’, ‘AGAF 0301-04’, ‘Garnem’, ‘Krymsk^® 1’, ‘Krymsk^® 86’, ‘PAC 847’, ‘PADAC 04-01’, ‘PADAC 150’, ‘PM 105 AD’, and ‘Rootpac^® 70’, were considered. Vegetative growth, chlorophyll SPAD index, leaf mineral status and deviation from the optimum percentage (DOP) index were determined. Leaf chlorophyll content varied depending on the rootstock. ‘PADAC 04-01’ and ‘ADAGAF 04-03’ showed higher chlorophyll index. The lowest SPAD values were observed for the most dwarfing rootstock ‘Krymsk^® 1’, which showed visual chlorosis symptoms, and lower leaf mineral contents compared to the other rootstocks. Peach trees on Prunus rootstocks showed differences in leaf macronutrient and micronutrient content. ‘Rootpac^® 70’, ‘ADAGAF 04-03’ and ‘PADAC 04-01’ had better adaptation under warm Tunisian conditions but high ΣDOP index. The most invigorating ‘Garnem’ had the highest imbalanced nutritional status, but continues to perform well under warm conditions. Interesting results were obtained with ‘Rootpac^® 70’ showing one of the best balanced nutritional values (average ΣDOP index). However, the most dwarfing rootstock ‘Krymsk^® 1’ presented the worst adaptation to the studied warm Mediterranean conditions.     

Interstock effects on growth and 45Ca distribution in ‘delicious’ apple seedlings 1

Comparisons were made of the ⁴⁵Ca uptake of ‘Redchief Delicious’ apple seedlings (Malus domestica Borkh) grown on ‘York Imperial’ rootstocks with interstocks of ‘Redchief Delicious’, M9 and short, medium and long internode ‘Delicious’ stocks. Seedlings were grown in aerated complete nutrient solutions. Applied ⁴⁵Ca was readily translocated to rootstocks, interstocks, scions and leaves of M9 and short internode combinations.

⁴⁵Ca accumulated to a much greater extent in rootstock and the interstock than the scion. Applied ⁴⁵Ca was translocated much more readily to the bark than to the wood.     

Effects of High Boron Concentration and Scion-Rootstock Combination on Growth and Nutritional Status of Olive Plants

Own rooted olive plants (Olea europaea L.) of the cvs. ‘Megaritiki’ (M), ‘Chondrolia Chalkidikis’ (C), ‘Amfissis’ (A), ‘Kalamon’, ‘Koroneiki’, ‘Agiou Orous’, and wild olives, as well as the scion x rootstock combinations CxC, MxC, MxM, AxM, CxM, AxA, and CxA were irrigated with a nutrient solution containing 10 mg boron (B)/L for two months. In all the own rooted plants and in the rootstock—scion combinations of the same cultivar stem growth rate was decreased due to high B. The lowest B concentration in leaves and roots was found in ‘Kalamon’ and wild olives, respectively. ‘Megaritiki’ had higher leaf B concentration when grafted on ‘Megaritiki’ or ‘Chondrolia Chalkidikis’ compared to own rooted plants. The same cultivar as own rooted plant had higher root B concentration than as rootstock of the other tested cultivars.     

接种AM真菌对采煤沉陷区文冠果生长及土壤特性的影响

煤炭井工开采往往造成地表塌陷,导致了土壤养分贫瘠和水分缺乏,土壤沙化和水土流失,从而限制了当地矿区植被生长,而丛枝菌根真菌(arbuscular mycorrhiza fungi,AM真菌)对植被生长有促进作用。以文冠果为宿主植物,采用野外原位监测和室内分析方法,研究了未接种和接种丛枝菌根真菌对采煤沉陷区复垦植物文冠果生长和土壤特性的影响。结果表明:与未接种AM真菌处理相比,接种AM真菌显著提高了文冠果根系菌根侵染率和土壤根外菌丝密度,7月接种AM真菌文冠果的株高、冠幅和地径提高了31.89%,23.07%,9.89%。同时,9月接种AM真菌处理的根际土壤全氮、碱解氮和有机碳含量分别比对照组增加0.29g/kg、13.0mg/kg和1.4g/kg,接种AM真菌显著提高了根际土壤的含水率、总球囊霉素和易提取球囊霉素,而速效磷和速效钾的含量显著降低。相关分析结果表明,菌根侵染率、土壤根外菌丝密度与根际土壤理化性质之间存在协同反馈效应。因此,接种AM真菌促进了采煤沉陷区复垦植被文冠果的生长和土壤的改良,这对矿区水土保持、维持生态系统稳定性和持续性具有重要意义。     

稻壳炭对紧实土壤中苹果根系硫同化酶活性、H2S含量及根系构型的影响

  【目的】   苹果种植后土壤很少翻动,根系常受土壤紧实胁迫。研究在土壤中掺混稻壳炭提高苹果根系硫同化代谢以及根系构型的效果,为果园土壤管理提供技术参考。   【方法】   以砧木分别为平邑甜茶和八棱海棠的两年生‘红富士’苹果 (Malusdomestica ‘Red Fuji’) 幼树为试材进行盆栽试验。对掺入和没掺入稻壳炭的土壤分别进行镇压 (土壤紧实度值分别为1558和1572 KPa) 和不镇压 (土壤紧实度值分别为923和939 KPa),共4个处理。苹果幼树移栽成活后60天,测定土壤孔隙度、氧气浓度和水溶性硫含量,分析苹果根系硫酸根和硫化氢 (H₂S) 含量及ATP硫酸化酶 (ATPS)、O-乙酰丝氨酸裂解酶 (OASTL) 和L-半胱氨酸脱巯基酶（L-CD）、D-半胱氨酸脱巯基酶 (D-CD) 活性,以及根系活力和形态构型等。   【结果】   镇压处理显著降低了土壤中水溶性硫含量,降低了八棱海棠和平邑甜茶为砧木的苹果幼树根系硫酸根含量,降低了根系ATPS、OASTL和L-CD、D-CD活性以及内源H₂S含量,并显著降低根系活力、根长密度、根系长度、根系体积和根系分形维数,在平邑甜茶为砧木的幼树根系中的降低幅度大于八棱海棠砧木。无论是否镇压土壤,掺入稻壳炭均提高了土壤孔隙度、土壤氧气浓度以及不同形态硫含量,提高了苹果根系硫酸根和内源H₂S含量,根系ATPS、OASTL和L-CD、D-CD活性,根系活力,根系长度,根长密度和根系分形维数,且在紧实土壤中八棱海棠砧木的提升幅度大于在平邑甜茶砧木中,两种砧木的苹果幼树在紧实土壤中的提升幅度均大于在正常土壤中。   【结论】   土壤紧实显著降低土壤水溶性硫含量,抑制苹果根系硫代谢和根系生长,在土壤中掺入稻壳炭可以显著提高紧实土壤中苹果根系硫代谢、根系生长和根系分枝。因此,在苹果移栽时,在土壤中掺入一定比例的稻壳炭可以有效缓解土壤紧实对苹果根系生长和硫代谢的不利影响。