GA3及S3307对石刁柏生根的影响（简报）

石刁柏不同品种茎尖培养时,嘧啶醇和PP333等只能使易生根型品种生根,而对难生根型品种无效。5×10-5％的S3307液处理后内源GA水平下降,不仅使易生根型品种发根早、根多、健壮,且对难生根型品种的发根也有显著促进效应。内源GA1＋3＋4＋7含量过高是影响石刁柏发根的主要原因。     

10种植物插枝生根的生态生理

山茱萸、天目铁木的嫩枝在5月和9月间扦插有50％～80％的成活率,并以半木质化中上部的侧枝和切段为高。苗床光照为 5～20klX,而光照不足和通气不良会阻碍生根成活。红豆杉、六月雪春夏一年生枝扦插均有高的成活率。银杏、桂花、中华猕猴桃、长序榆、青檀宜于夏秋扦插。羊角槭成活率低。所有切枝用 100～200ppmNAA处理 1～12h对生根成活有一定促进作用。几种大龄树的侧枝扦插成活率远比幼树的低。     

富贵竹提取液的生根作用初探（简报）

富贵竹水提取液和甲醇提取液均促进水稻根系生长以及绿豆下胚轴和柳枝和扦插生根。     

S3307对小麦幼苗形态及某些生理特性的影响（简报）

用Ｓ３３０７处理小麦种子可以增蘖促根,增大叶面积和单株干物重,增强幼苗生理活性和抗逆力,从而起到壮苗的作用。     

黄腐酸对葡萄插条生根的影响（简报）

用0、100、200、400、800mg／L黄腐酸溶液浸泡巨峰而萄插条12h后催粮月余,其生根数、根长和芽的生长量都有增加。对穿的影响比根小,因而根／冠比值增加。     

S3307浸种对番茄幼苗生长和一些生理指标的影响

以不同浓度S3307浸种后,番茄幼苗株高降低,茎粗度增加,根冠比值、叶绿素、光合速率、可溶性糖、脯氨酸、Vc含量、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性均提高,丙二醛(MDA)含量和外渗电导率降低。说明S3307有助于培育壮苗,并提高番茄幼苗的抗逆性。5mg·L~(-1) S3307浸种的效果明显。     

植物激素和精胺对文竹组织培养生根的影响（简报）

文竹组织培养的生根需要IBA和适量KT,添加NAA和精胺也有利于生根。NAA预处理明显促进生根,培养基中无机盐和水解乳蛋白的量以低为宜。地上部的生长状况明显影响生根,生长适中的对生根有利。     

S3307对板栗某些生理特性和产量的影响（简报）

八年生和六年生板栗树于春季萌芽展叶期喷施 ５０～２００ ｍｇ·Ｌ~（－１） Ｓ３３０７后,叶片变小变厚,叶绿素、可溶性糖和淀粉含量增加,水势下降;果枝缩短,枝条和干径增粗,树体矮化;果实座蓬率、蓬均粒数和出实率增加,产量提高。     

S3307与生根粉混合施用对云南甜竹插条中水分含量、光合产物分配和生根的影响

S3307与ABT混合后处理的云南甜竹插条的水分上运加速,叶绿素降解延缓,光合速率提高,14C-光合产物向插条基部的转运增加,插条的生根率高于S3307或ABT单独处理的。     

富贵竹同一枝条不同切段扦插生根能力的比较（简报）

同一富贵竹枝条,其基部切段扦插的成活率、生根率和生根量大于中部和上部的切段。插条生根率与成活率、生根量均存在极显著相关（r≈0．9）。La（NO3）3和2,4－D对插条生根有明显的促进作用,La（NO3）3对上部切段插条不定根的诱导效果较2,4-D显著。     

S3307对盆栽一串红的矮化效应

一串红喷施S3307后,植株高度降低,株型紧凑,节间缩短,叶色变浓,花序整齐,花色鲜艳.以20 mg*L- 1 S3307喷1次的矮化效果为最佳.     

Silencing of the MADS-Box Gene SlMADS83 Enhances Adventitious Root Formation in Tomato Plants

Journal of Plant Growth Regulation - Adventitious roots (ARs) are important for the growth of plants and the improvement in their stress resistance and survival capacity. Although many genes have...     

Effects of Tomato Root Exudates on Meloidogyne incognita

Plant root exudates affect root-knot nematodes egg hatch. Chemicals in root exudates can attract nematodes to the roots or result in repellence, motility inhibition or even death. However, until recently little was known about the relationship between tomato root exudates chemicals and root-knot nematodes. In this study, root exudates were extracted from three tomato rootstocks with varying levels of nematode resistance: Baliya (highly resistant, HR), RS2 (moderately resistant, MR) and L-402 (highly susceptible, T). The effects of the root exudates on Meloidogyne incognita (M. incognita) egg hatch, survival and chemotaxis of second-stage juveniles (J2) were explored. The composition of the root exudates was analysed by gas chromatography/mass spectrometry (GC/MS) prior to and following M. incognita inoculation. Four compounds in root exudates were selected for further analysis and their allopathic effect on M. incognita were investigated. Root exudates from each tomato rootstocks (HR, MR and T strains) suppressed M. incognita egg hatch and increased J2 mortality, with the highest rate being observed in the exudates from the HR plants. Exudate from HR variety also repelled M. incognita J2 while that of the susceptible plant, T, was demonstrated to be attractive. The relative amount of esters and phenol compounds in root exudates from HR and MR tomato rootstocks increased notably after inoculation. Four compounds, 2,6-Di-tert-butyl-p-cresol, L-ascorbyl 2,6-dipalmitate, dibutyl phthalate and dimethyl phthalate increased significantly after inoculation. The egg hatch of M. incognita was suppressed by each of the compound. L-ascorbyl 2,6-dipalmitate showed the most notable effect in a concentration-dependent manner. All four compounds were associated with increased J2 mortality. The greatest effect was observed with dimethyl phthalate at 2 mmol·L^-1. Dibutyl phthalate was the only compound observed to repel M. incognita J2 with no effect being detected in the other compounds. Each of the four compounds were correlated with a reduction in disease index in the susceptible cultivar, T, and tomato seedlings irrigated with L-ascorbyl 2,6-dipalmitate at 2 mmol·L^-1 showed the best resistance to M. incognita. Taken together, this study provided a valuable contribution to understanding the underlying mechanism of nematode resistance in tomato cultivars.     

Cytokinin Production by Tomato Root: Occurrence of Cytokinins in Staled Medium of Root Culture

Cytokinins were released into the medium by cultures of excised tomato (Lycopersicon esculentum Mill.) root tips. A large portion was directly released from the proximal cut-end of the roots. The most active substance was found to co-chromatograph with zeatin riboside in both paper and Sephadex column chromatographies. The cytokinin activity after 7 days of growth was found about eight times higher in the medium as compared with that in the root tissues. When freshly excised root tips were subcultured throughout eight passages, the accumulation of cytokinin in the medium of each passage was approximately the same. These results show that the root tip is a main site of cytokinin synthesis.     

Cu2+ Reduction by Tomato Root Plasma Membrane Vesicles

Reduction of Cu2+ by plasma membrane vesicles isolated from tomato (Lycopersicon esculentum Mill.) roots was investigated. Plants were grown in hydroponic culture with complete nutrition for 4 weeks or were deprived of Fe for the last 7 d. Plasma membrane vesicles were prepared by aqueous two-phase partitioning. Reduction of Cu, Fe, and ferricyanide by plasma membrane vesicles was measured. An increase in the activity of all three pyridine-nucleotide-dependent activities was noted in plasma membrane preparations from Fe-deficient, compared to Fe-sufficient, plants. Solubilization and chromatographic separation of two plasma membrane electron transport systems indicated that the Fe-chelate reductase was probably responsible for reduction of Cu. Assays used a variety of Cu chelates, and for each the Cu activity in the assay was determined by the program Geochem PC. The rate of reduction of Cu correlated with the level of Cu activity, and results support the idea that free Cu2+ and not Cu chelates may serve as the true substrate for reduction. Reduction was observed only in assays in which Cu activity was equivalent to Cu-enriched or Cu-toxic soils. These results suggest that reduction of Cu by tomato root may have little or no physiological relevance under conditions experienced by the root in the soil.     

Selenium Transport in Root Systems of Tomato

Selenate and selenite transport through tomato root systemswere followed for periods up to 4 h after removal of the planttops, using ⁷⁵Se as a tracer. With selenate, ⁷⁵Se concentrations in the xylem exudate were6 to 13 times higher than in the external solution, and chromatographicanalysis showed that the selenium was transported as inorganicselenate ( ). With selenite, ⁷⁵Se concentrations in the exudate were alwayslower than in the external solution. Analyses of exudate samplesshowed that negligible amounts of selenium were transportedas inorganic selenite ( except at very high external selenite concentrations (500 ?M), when up to 7 percent was transported as selenite. Most of the selenium transportin selenite-fed plants was as selenate or as an unknown seleniumcompound, the relative proportions of these two forms varyingboth with time and with external selenite concentration. Additionof a 5-fold excess of sulphate over selenite had no detectableeffect on the concentrations of selenate in the exudate, butcaused substantial decreases in the maximum concentrations ofboth total selenium (c. 47 per cent decrease) and the unknownselenium compound (c. 69 per cent decrease). Addition of a 5-foldexcess of sulphite decreased the concentration of the unknown(c. 39 per cent) but caused a large (2.7-fold) increase in themaximum total selenium concentration in the exudate and a 7.9-foldincrease in the maximum concentration of selenate. The resultssuggest metabolic involvement in the uptake and long distancetransport of solenium supplied as selenite, despite lower ⁷⁵Seconcentrations in the xylem exudate than in the external solution.An attempt is made to incorporate the new and existing informationinto a selenium transport model.     

Preferential Promotion of Lycopersicon esculentum (Tomato) Growth by Plant Growth Promoting Bacteria Associated with Tomato

A total of 74 morphologically distinct bacterial colonies were selected during isolation of bacteria from different parts of tomato plant (rhizoplane, phylloplane and rhizosphere) as well as nearby bulk soil. The isolates were screened for plant growth promoting (PGP) traits such as production of indole acetic acid, siderophore, chitinase and hydrogen cyanide as well as phosphate solubilization. Seven isolates viz., NR4, NR6, RP3, PP1, RS4, RP6 and NR1 that exhibited multiple PGP traits were identified, based on morphological, biochemical and 16S rRNA gene sequence analysis, as species that belonged to four genera Aeromonas, Pseudomonas,Bacillus and Enterobacter. All the seven isolates were positive for 1-aminocyclopropane-1-carboxylate deaminase. Isolate NR6 was antagonistic to Fusarium solani and Fusarium moniliforme, and both PP1 and RP6 isolates were antagonistic to F. moniliforme. Except RP6, all isolates adhered significantly to glass surface suggestive of biofilm formation. Seed bacterization of tomato, groundnut, sorghum and chickpea with the seven bacterial isolates resulted in varied growth response in laboratory assay on half strength Murashige and Skoog medium. Most of the tomato isolates positively influenced tomato growth. The growth response was either neutral or negative with groundnut, sorghum and chickpea. Overall, the results suggested that bacteria with PGP traits do not positively influence the growth of all plants, and certain PGP bacteria may exhibit host-specificity. Among the isolates that positively influenced growth of tomato (NR1, RP3, PP1, RS4 and RP6) only RS4 was isolated from tomato rhizosphere. Therefore, the best PGP bacteria can also be isolated from zones other than rhizosphere or rhizoplane of a plant.

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-014-0470-z) contains supplementary material, which is available to authorized users.     

Suppression of Calcium Transport to Shoots by Root Restriction in Tomato Plants

Restriction of tomato roots by growth in small containers stronglysuppressed transport of ⁴⁵Ca²⁺ ions to new leaves and apices.Water transport, expressed on a leaf area basis, was marginallyreduced by root restriction, an indication that calcium transportwas more severely limited than water transport. (Received October 11, 1996; Accepted January 27, 1997)