水分胁迫下AM真菌对紫花苜蓿生长及抗旱性的影响

以摩西球囊霉(Glomus mosseae)为接种菌剂,以紫花苜蓿为研究对象,利用盆栽控水法,研究了水分胁迫下接种AM真菌对紫花苜蓿生长状况与抗旱性的影响。结果表明:水分胁迫时,接种AM真菌的植株体内叶片相对含水量、脯氨酸含量和可溶糖含量显著增加,细胞膜通透性、MDA含量和3种保护酶的活性明显下降;说明接种AM真菌可促进植物细胞渗透调节物质的累积,降低超氧自由基的产生,减缓水分胁迫对植物带来的伤害,促使植物更好地适应矿区干旱环境。     

根系修剪和接种丛枝菌根真菌对枳实生苗根系形态的影响

为探究根系修剪和接种丛枝菌根(AM)真菌对柑桔根系和植株生长的影响,以盆栽实生枳幼苗为试材,对根系修剪(切除1/2主根)和接种不同AM真菌(Diversispora versiformis、Funneliformis mosseae和Rhizoglomus intraradices)处理后植株生物量和根系形态变化进行了比较研究。结果表明,除D.versiformis外,根系修剪能显著提高F.mosseae和R.intraradices的侵染率。根系修剪降低了非菌根化植株地上部干重和植株总干重,但接种F.mosseae和R.intraradices后植株地上部干重、根系干重和植株总干重均显著增加,且接种F.mosseae的效果更好。根系修剪显著降低了植株主根长度,但三级侧根数量和一级侧根密度均显著增加,根系修剪下接种F.mosseae增加侧根数量和一级侧根密度的总体效应最优。根系修剪后接种F.mosseae和R.intraradices的植株根系表面积、投影面积和体积均显著增加,并增加了0～1.5 cm短根系的总长度。根系修剪和AM真菌对枳侧根的发生存在一定的叠加效应。     

AM真菌和解磷真菌对低磷土壤滨梅插条生根和生长的影响

以1年生木质化滨梅枝条为供试插条,采用砂性低磷土壤为基质进行盆栽试验,分别测定了接种摩西球囊霉(Glomus mosseae)、毛霉(Mortierella sp.)及其混合菌剂后,滨梅生根、生长、磷素营养和根系激素水平的相关指标,以研究AM真菌和解磷真菌对低磷土壤滨梅插条的促生效应。结果表明:3种菌剂接种后滨梅根系吲哚乙酸(IAA)和玉米素(Zeatin)的水平极显著高于对照(P0.01);插条的含磷量、土壤有效磷含量及滨梅插条根际土壤磷酸酶活性极显著高于对照(P0.01),植物的生根率、最长初生根的长度、根干重、地上部分干重、株高以及总叶面积等生根和生长指标显著优于对照(P0.05);AM真菌侵染率以混合菌剂接种最高,且对于滨梅插条磷素营养的改善和生根、生长的促进效应最为显著。研究表明,接种的3种菌剂改变了插条根系的激素代谢,强化了低磷土壤上滨梅插条的磷素营养,促进了插条的生根和植株生长;G.mosseae菌剂和Mortierella sp.菌剂的复合接种,对低磷土壤滨梅插条磷素营养的改善和生根、生长具有明显的互作效应。     

接种AM真菌对不同育苗基质中甜椒苗期生长的影响

研究比较普通土、秸秆有机土和草碳蛭石3种育苗基质中接种两种丛枝菌根真菌GM、GV对甜椒苗期生长的影响,结果表明：在营养含量较高的有机土育苗基质中,接种AM真菌对甜椒苗的影响最弱,而在营养水平较低的草碳蛭石无土育苗基质中,接种AM真菌对甜椒苗有显著的促进作用,其中AM真菌在草炭蛭石中对甜椒苗根系的侵染率也最高,而GM的接种效果优于GV。     

土壤施用PP333对枳实生苗生长和营养元素吸收的影响

2年生盆栽枳实生苗经0～5000ppm系列浓度PP333处理后,新梢抽发量、生长量、节间长度,主干粗度,新根发生量,根长度及单株鲜重等随处理浓度的升高而减少,但新根粗度随处理浓度增加而增加。PP333处理使新生枝叶及根中Zn含量减少,但似乎不减弱对K、Ca、Mg、Mn、Cu等元素的吸收,而P的含量相对稳定。     

AM真菌对NaCl胁迫下滨梅苗生长和营养元素吸收的影响

在温室条件下分别接种摩西球囊霉Glomus mosseae、透光球囊霉Glomus diaphanum和幼套球囊霉Glomus etunicatum,来观察盐胁迫下滨梅的生长反应.结果表明,接种了AM真菌的滨梅与对照相比,显著增加了滨梅幼苗的生长.接种了摩西球囊霉和幼套球囊霉的滨梅幼苗所含的干物质总量分别高出对照51.1％和49.5％,总叶面积分别高出对照36.4％和34.5％.NaCl胁迫下接种AM真菌的滨梅幼苗叶中所有养分含量除铁外都表现出相互作用,方差分析结果差异显著;摩西球囊霉和幼套球囊霉在提高滨梅苗的抗盐能力上比透光球囊霉更有效.试验结果表明,接种特定的AM真菌能够缓解土壤盐胁迫对滨梅的伤害.     

接种AM真菌对温室甜瓜产量及品质的影响

通过温室试验研究了接种2种AM真菌(GM,GV)对风味三号甜瓜产量和品质的影响。结果表明:苗期接种AM真菌能增加苗期甜瓜的植株茎粗、叶片叶绿素含量、光合速率,收获时可提高甜瓜的产量,改善营养风味品质,表现为甜瓜果实VC含量增高及硝酸盐与亚硝酸盐含量的显著降低,2种菌剂以GM的应用效果更好。     

枳实生苗抗旱丛枝菌根真菌菌种比较的研究

 盆栽条件下研究丛枝菌根真菌Glomus versiforme、G. mosseae、G. geosporum、G. diaphanum 和G. etunicatum 对正常水分和水分胁迫下的枳实生苗水分代谢的影响。结果表明, 在正常水分和水分胁迫下接种丛枝菌根真菌都明显增加植株的生长, 提高叶片可溶性糖、可溶性淀粉、可溶性蛋白质以及根系可溶性糖的含量。叶片超氧化物歧化酶、过氧化氢酶和过氧化物酶活性增强, 从而提高了植株的抗旱性。正常水分下以接种G. versiforme的效果最好, 水分胁迫下以接种G. mosseae的效果最好。     

AM真菌与根瘤菌接种对菜豆生长的影响

以泰国无筋地豆为试材,在温室盆栽的条件下,分别单接种丛枝菌根真菌(AM)、单接种根瘤菌(RH)、双接种丛枝菌根真菌和根瘤菌(AM+RH),以不接种为对照(CK),研究不同接种方式对菜豆植株生长、结瘤、单株总荚质量、AM菌根侵染率、植株氮磷含量及吸收量、单株黄叶率等的影响。结果表明:双接种AM+RH能显著促进菜豆植株的生长,植株总干质量比单接种AM、单接种RH和CK分别增加34.3%、82.3%和57.9%;双接种AM+RH可提高菜豆单株总荚质量,促进菜豆植株对氮、磷元素的吸收,全株吸磷量比单接AM、单接RH和CK分别增加42.1%、314.8%和325.4%,全株吸氮量比单接种AM、单接种RH和CK分别增加36.8%、45.1%和43.4%;AM真菌与RH具有协同促进的作用,且AM真菌能有效提高菜豆的抗性,减少叶片变黄的比率,减轻了病害为害程度。     

不同成熟度枳和枳橙种子发芽率影响机理初探

为探索枳和枳橙种子发育过程中积累的内源激素、糖类与发芽率之间的兲系,分别选取不同成熟期的枳和枳橙果实,测定其种子IAA、ABA、淀粉、果糖、蔗糖、葡萄糖、可溶性糖含量。结果表明:枳种子IAA、ABA、果糖、蔗糖对发芽率有促迚作用,淀粉、葡萄糖对种子发芽率有抑制作用,但作用均不显著;枳橙种子IAA、ABA、果糖、蔗糖对发芽率有抑制作用,淀粉、葡萄糖对发芽率有促迚作用,其中发芽率与果糖含量呈显著负相兲,说明枳橙种子果糖对发芽率有显著抑制作用。     

Emergence and seedling growth of pepper as influenced by soil compaction,nutrient status and moisture regime

Studies on the influence of seed-bed condition on the emergence and development of pepper seedlings (Capsicum frutescens L.) revealed that seed-bed compaction delayed and reduced seedling emergence. High nutrient and organic matter content accentuated the severity of soil compaction, regardless of whether the soil moisture was low or high. Influence of compaction was less on “dry” poor soil. Best seedling emergence was obtained from “moist” crumbly “rich” soil. However, “moist” crumbly “poor” soil, moist compacted poor soil, “dry” crumbly rich soil and “dry” crumbly poor soil also gave very high seedling emergence. The dry compacted rich soil gave the poorest cumulative emergence figures. High soil moisture regime and high nutrient content reduced the severity of soil compaction on seedling root and shoot development. Soil compaction also caused abnormal hypocotyl morphology in seedlings that germinated but failed to emerge.     

Transformation of trifoliate orange with rice chitinase gene and the use of the transformed plant as a rootstock

RCC2, cDNA clone encoding rice class-I chitinase, was introduced into trifoliate orange (Poncirus trifoliata Raf.). Chitinase activity of the transformed plants was higher than that of the non-transformed plants. The introduced gene was not detected in the scions grafted onto the transformed plants. The effect of the introduction of foreign gene into rootstocks on the scions was discussed.     

多效唑对葡萄组培幼苗生长发育的影响

多效唑(又称PP333、Paclobutrazol、氯丁唑)是一种植物生长调节剂,抑制植物体内GA的生物合成,可抑制多种植物的纵向生长和促进横向生长[1～5].     

Differences of hyphal and soil phosphatase activities in drought-stressed mycorrhizal trifoliate orange (Poncirus trifoliata) seedlings

Differences of hyphal and soil phosphatase activities between mycorrhizal and non-mycorrhizal plants were less studied under drought-stressed (DS) conditions. In a pot experiment, fungal alkaline phosphatase (FALP), and succinate dehydrogenase (FSDH), soil phosphatase activity, both soil and plant P contents were compared in 6.5-month-old trifoliate orange (Poncirus trifoliata) seedlings under 80 days of DS with or without inoculations by arbuscular mycorrhizal fungi (AMF, Glomus diaphanum, Glomus mosseae or Glomus versiforme). Plant growth and biomass production under DS were significantly higher in mycorrhizal than in non-mycorrhizal seedlings. Both the FALP and the FSDH activities under DS were significantly reduced in these three Glomus inoculated seedlings. In general, similar soil neutral and alkaline phosphatase activities, but significantly higher soil acid and total phosphatase activities, were exhibited in mycorrhizal than in non-mycorrhizal seedlings under both the well-watered (WW) and the DS. Both leaf and root P contents were significantly higher in the AM colonized seedlings, but soil available P contents were lower in the growth media with AM seedlings. Our results showed that higher hyphal enzymes’ activities, soil acid and total phosphatase activities, and plant P contents in AM colonized seedlings, particularly in Glomus mosseae-colonized seedlings and/or under DS, would result in a better growth of the host plants, which might be the basis for enhancing drought tolerance in plants.     

菌糠基质在中果型西瓜育苗上的应用效果

为研发适合西瓜集约化育苗的基质,减少传统不可再生基质的使用,选择食用菌生产废弃的香菇和平菇菌糠作为中果型西瓜‘日本777’的育苗基质,与常规使用的商品基质和农家粪基质进行应用效果比较。结果表明:在西瓜苗期阶段,香菇和平菇菌糠基质较商品基质和农家粪基质在根鲜质量、植株高度、茎粗度、叶面积方面都有较大程度的增加;但定植后西瓜各生育期植株长势差异较小。在果实品质性状方面,香菇和平菇菌糠处理的中心可溶性固形物分别达到11.75%、11.68%,高于商品基质和农家粪处理,在667 m2产量上,香菇、平菇菌糠同样领先,分别达到了4 831.25、4 753.49 kg,但经统计分析在5%水平上都没有形成显著差异。综上所述,香菇和平菇菌糠适合作为中果型西瓜育苗基质,成本低又环保,且苗期阶段有利于促进植株生长。     

Evaluation of strains of Poncirus trifoliata and trifoliate orange hybrids for resistance to Phytophthora root rot

Ten strains of Poncirus trifoliata (L.) Raf. and 6 trifoliate orange hybrids were evaluated for resistance to root rot caused by Phytophthora nicotianae B. de Haan var. parasitica (Dast.) Waterh. A high degree of resistance was shown by Rubidoux trifoliate and Trifoliate orange (Srirampur). Trifoliate orange hybrids, in general, were less resistant than P. trifoliata strains. The usefulness of different parameters in the assessment of root damage are briefly discussed.     

石灰对秋葵幼苗生长的影响

为解决秋葵育苗中死苗的问题,以秋葵为试材,研究了在秋葵育苗过程中施用石灰对其幼苗生长发育的影响,结果表明,施用一定浓度的石灰能促进秋葵根系发育,提高根系活力、根系质量、根冠比、侧根数;能显著地增加秋葵幼苗的叶面积、植株高度和茎粗度。其中以采用4%的石灰均匀拌入土壤的方式效果较好,根系活力、根系质量、根冠比、侧根数分别较对照提高19.17%、62.86%、65.78%、67.27%、4.61%。     

钾、镁相互作用对龙眼幼苗生长的影响

在酸性土壤中进行了龙眼幼苗钾、镁肥不同施用量的盆栽试验，结果表明，钾与镁均显著影响龙眼幼苗的生长，且钾、镁之间存在明显的交互作用；当钾肥与镁肥的施用比例为2：1时，能获得龙眼幼苗的最高生物量，由此得出龙眼叶片K／Mg的适宜比值为2．43。     

Short- and long-term growth of navel orange fruit

Summary

Seasonal patterns of fruit development of young and mature `Bellamy' navel orange trees were measured from mid November to late July. Growth of whole fruit, expressed as fresh or dry weight, was best described by a fourparameter logistic curve (R<sup>2</sup>>0.99). The fresh weight growth curves of fruit from young and mature trees were not significantly different. Dry weights and fresh weights were linearly correlated (R<sup>2</sup>>0.99). The relationship between relative growth rate (RGR) of whole fruit and time was best described by two linear regressions (R<sup>2</sup>>0.98, 0.92, respectively). The two linear phases of RGR did not correspond to ontogenic phases of fruit development as described by Bain (1958). Increases in whole fruit and pulp radii, and whole fruit, pulp, rind and albedo volume during fruit development followed single sigmoidal patterns (four parameter logistic function, R<sup>2</sup> >0.99). Relative changes in the volume of the structural parts of the fruit were small during Stage III of fruit development. Diurnal variations in growth and rind temperature of fruit from young (under continuous irrigation) and mature (under weekly irrigation) `Leng' navel orange trees were recorded during Stage II of fruit development. Inelastic growth measured by LVDTs was described better by diurnal diameter means (max 1 min)/2 than diurnal maxima or minima. Diurnal diameter means of fruit from young trees showed a significant (R² = 0.42, P<0.0001) relationship to daily ambient temperature maxima, and the diurnal growth profiles paralleled the diurnal temperature profiles of the rind. In contrast, the diurnal growth rhythms of fruit from mature trees were insensitive to ambient temperature maxima and the diurnal rhythms appeared to reflect the water status of the tree.