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Grapevine fanleaf virus (GFLV), responsible for fanleaf degeneration, one of the most severe virus diseases of grapevines worldwide, causes substantial crop losses, reduces fruit quality and shortens longevity of grapevines. GFLV is transmitted from grapevine to grapevine by the ectoparasitic nematode Xiphinema index and belongs to genus Nepovirus, family Comoviridae. Since the discovery of the nematode vector in the late _50s and the identification of GFLV as the agent of fanleaf degeneration in the early _60s, a wealth of information was accumulated on its transmission, biological properties and serological characteristics, as well as on structure and expression of GFLV genome. Although dissemination of virus through propagation material has been drastically reduced over the past two decades by implementing rigorous certification schemes and establishing quarantine facilities, effective strategies are still needed to control GFLV in vineyards. Recently, significant progress has been made on the elucidation of the functions of most GFLV proteins, in particular the ones involved in critical steps of virus multiplication cycle, including RNA replication, cell-to-cell movement and transmission by X. index. New insights have also been gained into population structure and genomic variability among isolates from naturally infected vineyards, which have opened new pathways for designing alternative control strategies. This review article offers a comprehensive overview of the most significant advances made over the past 15 years on GFLV and discusses novel control strategies for one of the major threats to grapevine industry worldwide [Il Virus della foglia a ventaglio della vite (GFLV), responsabile della degenerazione a ventaglio, una delle più gravi malattie della vite a livello mondiale, causa rilevanti perdite produttive, riduce la qualità dell'uva e la longevità delle piante. Il GFLV viene trasmesso dal nematode ectoparassita Xiphinema index e appartiene al genere Nepovirus, famiglia Comoviridae. Dalla scoperta del vettore alla fine degli anni '50 e dall'identificazione del GFLV come agente della degenerazione a ventaglio nei primi anni '60, sono state accumulate molte informazioni su trasmissione, proprietà biologiche, caratteri sierologici e struttura ed espressione del genoma del GFLV. Sebbene la diffusione del virus col materiale di moltiplicazione sia stata ridotta drasticamente negli ultimi venti anni con rigorosi schemi di certificazione e strutture per la quarantena, sono tuttora necessarie strategie efficaci per il controllo del GFLV. Recentemente sono stati conseguiti progressi significativi sul chiarimento delle funzioni della maggior parte delle proteine del GFLV, in particolare quelle coinvolte nei passaggi critici del ciclo di moltiplicazione, comprendenti la replicazione dell'RNA, il movimento da cellula a cellula e la trasmissione tramite X. index. Sono state inoltre acquisite nuove informazioni sulla struttura e variabilità genomica delle popolazioni negli isolati provenienti da vigneti infetti naturalmente, che hanno aperto nuove strade per mettere a punto strategie di controllo alternative. Questa rassegna offre un panorama dei progressi più significativi conseguiti negli ultimi 15 anni sul GFLV e discute le strategie innovative di controllo di una delle maggiori minacce per la viticoltura mondiale]

The objective of this study was to evaluate the behaviour of acid limes 'Tahiti' (Citrus latifolia Tanaka) and 'Galego' (Citrus aurantifolia Swingle), mandarin (Citrus reticulata Blanco) 'Cravo' and 'Lee' tangelo and 'Murcott' tangor hybrids, grafted on four rootstocks: 'Rangpur' lemon (Citrus limonia Osb.), 'Sunki' (Citrus sunki Hort. ex Tan.) and 'Cleopatra' (Cirus reshni ex Hort. Tan.) mandarin, and 'Carrizo' citrange (Citrus sinensis (L.) Osb. x Poncirus trifoliata Raf.). The experiments were carried out at the experimental farm of Embrapa Acre, Amazon, Brazil. The 'Tahiti' acid lime presented the highest average of fruit production (115.14 kg/plant), production for canopy volume (2.49 kg m-3) and number of fruits (836.80/plant), for that grafted on the rootstock 'Sunki' mandarin. The 'Carrizo' citrange and 'Rangpur' lime induced on the 'Galego' acid lime presented the highest fruits medium production (126.81 e 85.80 kg/plant), production for canopy volume (1.82 e 1.28 kg m-3) and number of fruits (2,619.93 e 1,810.80/plant). The rootstock 'Rangpur' lime promoted the highest mean production (90.56 kg/plant) in all mandarin and hybrid cultivars. In spite of the mandarin and hybrids presented the same behavior, the 'Sunki' mandarin induced a good average production (69.67 kg/plant) and average number of fruits (500.94/plant) on the 'Murcott' tangor.

Sambacaitá (Hyptis pectinata L.), Lamiaceae, is a perennial shrub with an important medicinal value in the Northeast region of Brazil. The study of the propagation and the initial growth of the plants are so important that the transplanted is done at the appropriate time, favoring the development of the plants on the ground. This work aimed to evaluate the initial growth of H. pectinata seedlings during the days of the transplant. We used a completely random design with the treatments: days after the transplant (15; 22; 29 and 36), with four replicates of 10 plants each. The assay was held in the Seeds Laboratory/CCA/UFC, in Fortaleza-CE, in September and October 2004. The seedlings were planted in polyester trays and kept in the greenhouse with continuous nebulization and timer. The analyzed variable: height of the plant, leaves number, length and width of the foliar limb, weight of the dry substance of the aerial part, the root and total, and the relation of the weight of the dry substance of the aerial part/root. We concluded that the period of 22 to 29 days is the best time to take the H. pectinata seedlings to the field, ocurring from this time the growth of the plants.

Aiming to study the most appropriate method to overcome the dormancy in brauna seeds, experiments were conducted at the Universidade Federal do Ceará, in the period of February to July, 2004. We tested three methods (mechanical scarification; chemistry scarification; hot immersion in water) and control. We evaluated the percentage, velocity and average time of germination. We used 200 seeds, with four replicates of 50 seeds each. They were sown in plastic white trays containing substrate sand of river wash and sterilized in heater to 105° ± 3°C for 24h. Then they were moistened in the proportion of 60% of field capacity with water from the faucet. We did daily irrigations to maintain the dampness appropriate to the germination of seeds. A completely randomized design was used and the averages compared by the Tukey Test at 5% of probability. The most indicated method to overcome the dormancy in brauna seeds was mechanical scarification.

Cylindrica Luffa Roemer is a climber specie of the Cucurbitaceae family, originally from the Asia and Africa tropical. It is has been used in popular medicine as purgative and abortive. The use of phytotherapeutic products has proven to be very attractive for the marketing. Nonetheless, exploitation of plant species in such extractive way, may lead to endangerment of the species. This work aimed at studying the effects of pre-soaking, as well as various substrates, on the seedling production of L. cylindrica. For that, a factorial scheme (2 x 5), in a completely randomized design, with four replications of twelve seeds each was applied. Seeds were studied with or without soaking and under the following substrates: sand, soil, hummus, soil plus hummus, and soil plus hummus plus sand. The assay was carried out in the Seed Laboratory/CCA/Federal University-Ceara State, from March to April 2005. Seeds were sown in the substrates specified above, in trays composed of 72 cells. Upon sowing, seeds were taken to the greenhouse for a period of 25 days, remaining there since germination to the final evaluation. Percentage of seedling, seedling speed of emergency index, average seedling time of emergency, plant height, leaf number, dry weight of the plant aerial and underground parts were studied. Significant interaction was observed only for root length. Substrates and soaking showed to be significant for all the variables, excepting the percentage of emergency in pre-soaked seeds. It may be concluded first that pre-soaking favors seedling emergency, and second that seeds emerge faster when the substrate is sand. Plants grown in hummus, however, were more vigorous, as compared to the remaining substrates.