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International audience; In Martinique or La Reunion, French authorities recently banned the use of pesticides for the management of "soil-borne pathogens" on pineapple after several decades of intensive monoculture where the natural balance between beneficial and harmful communities of soil organisms has disappeared. Today, increasing infestation of pineapple by the nematode R. reniformis and other "soil-borne pathogens" causes severe damage to the crop. New cropping systems with innovative ecological nematode management are needed. An eco-friendly cropping system, which comprised rotation of sunn hemp (C. juncea), pineapple, a natural grass fallow and another cash crop, eggplant, consistently reduced the inoculum of nematodes. Nematode populations were reduced by 86.4%, 82% and 46.5% respectively under pineapple, sunn hemp and grass fallow compared to infestations of eggplant (3456 nematodes .100g(-1) of soil) after several rotations. Integrating a chemical induction of systemic resistance or application of an endophytic bacteria recovered from pineapple roots, Bacillus sp. GVS2, helped maintain low populations of nematodes during the vegetative cycle. On two pineapple varieties, MD2 and Victoria (Queen), two different treatments were applied monthly in the field, methyl jasmonate (10(-4) M, 10 ml per plant), or a suspension of Bacillus sp. GVS2 (10(8) CFU ml(-1), 10 ml per plant) isolated from pineapple roots. After eight months, the nematode populations were reduced respectively on MD2 and Victoria (Queen) by 58.3% and 50.3% with the methyl jasmonate and by 59.6% and 54.3% with the Bacillus sp. GVS2 compared to controls. Because of the efficiency of sunn hemp in reducing the inoculum of nematodes, no significant differences in vegetative growth were observed using the D leaf weight and the estimated root length densities (RLD). The potential of pest management through eco-friendly cropping systems for pineapple with a biocontrol for nematodes with no pesticide is discussed.

Bananas and plantains (Musa spp.) are among the most important crops in the world providing staple food for hundreds of millions of people. However, banana production has been devastated by fungal infestations caused by Fusarium oxysporum f. sp. cubense (Foc). Despite the fact that there is very little known on the role of microbial metabolites in the molecular mechanism of Foc infections, it has been proposed that the toxins fusaric acid and beauvericin produced by Foc play an important role during pathogenesis. The aim of this contribution was to study the toxic components of culture filtrates (CF) of Foc and to isolate the extracellular microbial metabolites involved in the plant response. An in vitro bioassay was used to evaluate the production of phytotoxic metabolites as well as the specificity of culture from a strain of Foc belonging to VCG 01210 (race 1). A host‐specific CF was obtained and the phytotoxic compounds characterized as fusaric acid, beauvericin and fumonisin B1. Despite the presence of these nonspecific toxins, a water‐soluble extract from the CF induced protection to the main phytotoxic fraction, measured by lesion area. This hydrophilic fraction induced a fast and strong response of just jasmonic acid (JA)‐dependent defence genes rather than salicylic acid (SA)‐ and ethylene (ET)‐response genes in resistant cultivars. Extracellular proteins isolated from CF of Foc provide an important source for further investigations on the molecular basis of the interaction between Foc and banana.

Monoculture and intensive use of pesticides have reduced the biodiversity of agrosystems and increased the imbalance between pathogenic and beneficial organisms. In the past, pineapple pests were generally controlled by pesticides, but today very few pesticides are authorized. In fragile environments like in the French Antilles, there is a growing public demand for the prevention of environmental risk. Agricultural research is responding by designing new cropping systems based on the ecological intensification of farming practices and alternative ways of managing pests. In Martinique, our strategy is based on agrosystems with increased biodiversity, restored ecosystem functions, enhanced bioregulation and beneficial interactions between plants and microorganisms, including natural defenses (systemic resistance). The aim of our current work is to answer two needs and to confirm several hypotheses:!) reduce pathogenic inoculum by using non-host rotation plants selected for their functional traits (non-host status, biomass production, balanced rhizosphere microflora); 2) select crop cultivars that are able to develop systemic resistance and to adapt their metabolism to environmental changes: we hypothesize a relationship between plant adaptability to biotic (defense genes) and abiotic stresses (genes for cysteine-proteases and their inhibitors, phytocystatins); 3) The reliability of systemic resistance at field level depends ona plant's ability to tolerate pathogens despite abiotic stresses, since such stresses may interfere; 4) Pineapple root system naturally bear diazotrophic bacteria ( endophytic) that are potential inducers of systemic resistance. Finally, we aim to design cropping systems that reduce soil borne pests before the pineapple crop is planted, and to create an environment that subsequently both enables bioregulation and reduces re-infestation of pineapple by the parasite. (Resume d'auteur)

We hypothesized that inducing systemic resistances can contribute to the control of the nematode Rotylenchulus reniformis in pineapple. In greenhouse experiments conducted in Martinique, the pineapple cultivars Smooth Cayenne and MD-2 were treated with methyljasmonate (JAME) and salicylic acid (SA), elicitors of induced systemic resistance (ISR) and systemic acquired resistance (SAR). The efficacy of the elicitors was tested by inoculating plantlets grown in individual pots with a monospecific population of R. reniformis reared on Vigna unguiculata . The final nematode populations, 45 days after inoculation on MD-2 treated with JAME were reduced by 67.0% ( p = 0.006). Nematode populations on MD-2 plants treated with SA were reduced by 55.8% ( p = 0.016). Nematode populations on SC were not reduced by the elicitors. In a second experiment, using split-root systems, JAME was applied to MD-2 plantlets and enzymatic activities involved in plant defense and stress responses were monitored for 14 h after treatment. Additional pots were inoculated with nematodes 24 h after JAME treatment and examined ten days later. Transient stress was observed along with an increase in enzymatic response after inoculation with nematodes. These results showed that the MD-2 was primed through an ISR by JAME. The question now arises whether ISR can be specifically induced only in certain pineapple cultivars. Results are discussed from the perspective of introducing new strategies to manage pineapple nematodes.

"Smooth Cayenne", accounting for 90% of processing pineapple, has been the backbone of the global pineapple industry for more than a century. Cultivars of the Cayenne group have a high content of total soluble sugar and acidity. Queen group pineapple, mainly for fresh consumption, contains high sugar and moderate acidity. Both sugar and acidity are low in Spanish group cultivars. "Perola" is one of the most important cultivars of the Pernambuco group, with a higher total soluble sugar (14.6°Brix) and a lower acidity (0.37%). The sugar content of 'Perolera' cultivar was 14.1°Brix and the acidity was 0.76%. Hybrid 'MD-2' is a famous cultivar dominating the world fresh pineapple ni.arket. The average percentage ofTSS in MD-2 is 1-2% higher than "Sn1ooth Cayenne". The acidity is lower than that of"Smooth Cayenne". Total sugar contents in 16 modern pineapple cultivars varied from 81.59 to 124.41.65 mg/g FWThe average value (108.14mg/g FW) was higher than that in traditional cultivars (106.29 mg/g FW). However, the highest sugar content was lower than that in traditional cultivars (137.89 mg/ g FW). The values of total organic acid in modern cultivars changed from 1.80mg/g FW to 6.90mg/g FWThe lowest, highest, and average contents of total organic acid in modern cultivars were lower than those in traditional cultivars. Total dietary fib er content varied from 1.46% to 2.80% FWThe average contents of NDF, ADF, CEL, HC, ADL, TP, WSP, and protopectin in 12 cultivars analyzed were 32.70, 20.65, 16.96, 12.24, 2.98, 3.06, 1.16, and 1.91mg/100 g DW, respectively. Vitamin C, vitamin A, vitamin B3, and vitamin B6 contents in 11 varieties changed between 0.10 and 0.23mg/g, 0.0016-0.0038mg/g, 0.0038-0.024mg/g, and 0.0045-0.067 mg/g respectively. It seems that pineapple is a good source of vitamin A, vitamin C, and vitamin B6. Both total polyphenols and flavonoids could be the main components responsible for the antioxidant capacities in pineapple fruit. Total phenolic contents showed significant variations among different genotypes, ranging from 25.71 to 72.57mg GAE/100g FW Catechin, epicatechin, and sinapinic acid were the predominant phenolic compounds. The TF contents of the pulp extracts had significant differences, which varied from 10.40 to 50.57n1g RE/100g FW "MD-2" and "Tainung4" exhibited higher antioxidant capacities than the other cultivars as determined by DPPH,ABTS, and FRAP methods. Eighty-three volatile compounds were detected in six pineapple cultivars, including 15 esters and 57 alkenes and terpenes. Total concentration of aroma in "Tainungl 7" was the highest (8842.09 μg/kg), while in "Queensland Cayenne" it was the lowest (1408.66μg/kg) . Butanoic acid 2-methyl-methyl ester, butanoic acid, 2-methyl-ethyl ester, hexanoic acid methyl ester, hexanoic acid, ethyl ester, and decanal appeared to be the main odor-active compounds. (Resume d'auteur)

We developed a standardized method to monitor the symphylids (Hanseniella sp.) populations in pineapple using bait and traps. Two methods for symphylid extraction and enumeration were tested. Two statistical methods, the "variance/mean" ratio and a spatial analysis (Moran and Geary indices) were used to describe the type of spatial distribution of the populations. This bait and trap method allows a good evaluation of the symphylid populations. The ratio between adults and larvae may be used as an indicator of the population growth statute. Data collected on a rotation crop for pineapple, Mucuna pruriens var. utilis, showed that symphylids populations are highly aggregated following a negative binomial distribution. Finally, the method has been validated in plots of 'MD-2' pineapple to monitor the symphylids populations at different stages of development of the crop. (Resume d'auteur)

BACKGROUND: Symphylids (Hanseniella sp.) are polyphagous soilborne parasites. Today, symphylid populations on pineapple are monitored by observing root symptoms and the presence of symphylids at the bottom of basal leaves. The authors developed a reliable method with a bait and trap device to monitor symphylid populations in pineapple or fallow crops. The spatial distribution of the symphylid populations was evaluated using the variance/mean ratios and spatial analyses based on Moran's and Geary's indices. The method has been tested to monitor symphylid populations at different developmental stages of pineapple. RESULTS: Adding potato baits to the soil samples increased the trapping efficiency of symphylids when compared with 'soil only' and 'bait only' methods. The handling of the samples is also facilitated by the new device. Results showed that the vertical distribution of symphylids may be uniform deeply inside the soil profile under pineapple, up to 50 cm. Results showed that symphylid populations are highly aggregated, showing a spot area about 4-6mwide for their development. CONCLUSION: The new method allows better and easier evaluation of symphylid populations. It may be very useful in the evaluation of new IPM methods to control symphylids under pineapple. (Resume d'auteur)

Due to consumer pressure, the use of nematicide on pineapple farms must be strongly reduced and is presently forbidden in EU territories according to the new EU regulations. Different ways to control soil born parasites are under investigation and the research on the tolerance or resistance of varieties to nematodes is one of them. In Martinique a screening method is being developed based on greenhouse cultivation in tanks. The behavior of different varieties from CIRAD germplasm was studied after infestation with the nematode Rotylenchulus reniformis. Growth characteristics and nematode populations were observed during six months covering the classical two flushes of root development observed in our tropical conditions. ´D` leaves weight and length as well as plant opening were measured every month, the plant shoot and root system were analyzed six months after planting. Preliminary results indicate that plants of the cultivar Smooth Cayenne show a susceptible pattern with strong vegetative growth reduction, meanwhile MD-2 plants show a tolerance pattern with a high multiplication of nematodes, but a relatively reduced effect on growth. Among Ananassoides sp., one variety shows a strong resistance pattern with little impact on vegetative growth. CIRAD hybrids show different resistance patterns from high susceptibility to good tolerance. This method will be used to detect potential parents for the breeding program, to evaluate new hybrids and to identify highly contrasting behaviors in order to study resistance/tolerance mechanisms to nematodes in pineapple. (Resume d'auteur)

Introduction. New ecological agricultural practices contribute to improved pest management and root development of pineapple, but tools to quantify the root development in cultural profiles in situ are lacking. The spatial distribution of the root length density (RLD) is a key factor for the absorption of water and nutrients. A robust model was sought to predict the RLD from the number of intersections of roots per unit area (RID) in a soil profile (trench method). Materials and methods. The procedure was based on the extraction of cubes of 1 dm3 of undisturbed soil on profiles under pineapple plants in triplicate, in which the RID was counted on three perpendicular faces of the cubes and the RLD was measured inside the cubes. Results and discussion. A model predicting the RLD (RLDc) from counting of the RID was developed and successfully tested: RLDc = RID.CO.CE, where CO = 2.65 is an orientation coefficient, and CE = 1.69 is an empirical coefficient. These two coefficients are fixed. Conclusion. The model allows an estimate of pineapple RLD and its spatial variability from simple counts of roots on a soil profile. A practical example of this model is given, characterizing and comparing in situ root profiles of pineapple plants. (Resume d'auteur)

Introduction . A l’instar d’autres secteurs de produits destines a l’alimentation humaine, une restructuration profonde de la filiere ananas martiniquaise s’accomplit pour repondre a de nouvelles exigences de securite alimentaire et de protection de l’environnement : management de la qualite sur l’ensemble de la filiere et exploitation de nouvelles varietes d’ananas. A partir de l’analyse des pratiques actuelles, les auteurs ont evalue les besoins de changements, puis propose quelques outils pour la mise en œuvre d’un systeme de production. Materiel et methodes . Des enquetes ont permis de connaitre les pratiques et strategies actuelles des producteurs d’ananas et d’etablir une typologie des exploitations. Un comite de pilotage associant des representants de l’ensemble de la filiere elabore le systeme de management de la qualite en se basant sur la norme Agriconfiance®. De nouvelles varietes sont en cours d’evaluation pour couvrir au mieux les besoins en ananas de qualite pour la transformation ou pour la vente en frais. Resultats et discussion . Les ecarts constates entre recommandations et pratiques culturales sont apparus tres variables mais souvent importants : trop d’intrants en general, soit les pesticides, soit les engrais, soit les deux. Le systeme de management applique repose sur un contrat entre une cooperative et les producteurs. Les regles de qualite sont fixees dans deux cahiers des charges, l’un concernant la qualite de la production au champ, l’autre, la qualite du fruit pour l’usine. Un systeme de tracabilite a l’echelle de la parcelle a ete elabore. Il permet la prevision et l’enregistrement de toute activite liee a la production, avec la parcelle comme unite de base. Enfin, de nouvelles varietes hybrides selectionnees par le Cirad ont pu etre testees dans le nouveau processus de transformation de la cooperative, donnant de meilleurs resultats que l’ancienne variete Cayenne lisse. Conclusion . La restructuration de la filiere ananas en Martinique resulte avant tout de considerations economiques. Cette demarche a conduit au developpement d’un programme global d’assurance qualite, avec instauration d’un systeme de tracabilite parcellaire, destine a garantir la securite alimentaire. Une homogeneisation des pratiques culturales est necessaire, en se rapprochant des recommandations pour ameliorer la qualite. Elles pourraient etre rassemblees dans un guide de culture specifique. L’adoption de nouvelles varietes d’ananas permettant d’obtenir de meilleurs rendements de transformation ainsi qu’une qualite accrue du produit frais ou transforme sera aussi un element determinant du succes de la demarche.

Food security, environmental protection, product 'traceability,' and quality improvement are new societal demands that producers within the Martinican pineapple industry must recognize. An in-depth reengineering of pineapple production systems and a re-haul of the pineapple processing plants are being implemented to meet consumer demands. A more reasonable style of agriculture (IPM) will allow for a drastic reduction in pesticide use. The introduction of new pineapple varieties which are better adapted to this new processing path (aseptic crush and cubes) will allow for an increase in production quality and for the creation of an individualized international market production. The "Agriconfiance" production certification and the processing plant certification (ISO) guarantees product 'traceability' and security. The PRAM (Pole de Recherche Agronomique de Martinique) (CIRAD-FLHOR) and the Ministry of Agriculture of Martinique have joined efforts to re-structure the pineapple industry, developing more specific research and professional support programs. The development of new varieties and hybrids and 'clean' production techniques is required daily by the industry in Martinique and throughout the Caribbean region. (Resume d'auteur)

Pineapple internal browning (IB) is a chilling injury that produces enzymatic browning associated with flesh translucency. Pineapple biodiversity allowed the investigation of how polyphenol oxidase (PPO) and peroxidase (POD) activities with their different isoforms are involved in the IB mechanism. Fruits of four varieties that expressed IB symptoms differently, Smooth Cayenne (SCay) and the hybrids MD2, Flhoran 41 (Flh 41), and Flhoran 53 (Flh 53), were stressed by cold. The susceptible varieties showed classical brown spots but different patterns of IB, whereas MD2 and controls showed no IB. Enzymatic activities were measured on fruit protein extracts and PPO and POD isoforms separated on mini-gels (PhastSystem). Only PPO activity was significantly enhanced in the presence of IB. Up to six PPO isoforms were identified in the susceptible varieties. PPO was barely detectable in the nonsusceptible variety MD2 and in controls. The number of PPO isoforms and the total PPO activity after chilling are varietal characteristics.

Symphylids (Hanseniella sp.) are polyphagous soilborne parasites. Today, symphylid populations on pineapple are monitored by observing root symptoms and the presence of symphylids at the bottom of basal leaves. The authors developed a reliable method with a bait and trap device to monitor symphylid populations in pineapple or fallow crops. The spatial distribution of the symphylid populations was evaluated using the variance/mean ratios and spatial analyses based on Moran's and Geary's indices. The method has been tested to monitor symphylid populations at different developmental stages of pineapple.Adding potato baits to the soil samples increased the trapping efficiency of symphylids when compared with 'soil only' and 'bait only' methods. The handling of the samples is also facilitated by the new device. Results showed that the vertical distribution of symphylids may be uniform deeply inside the soil profile under pineapple, up to 50 cm. Results showed that symphylid populations are highly aggregated, showing a spot area about 4-6 m wide for their development.The new method allows better and easier evaluation of symphylid populations. It may be very useful in the evaluation of new IPM methods to control symphylids under pineapple.