Search results for "Citrus"

Ploidy manipulation and citrus breeding, genetics and genomics

2020

Polyploidy appears to have played a limited role in citrus germplasm evolution. However, today, ploidy manipulation is an important component of citrus breeding strategies. For varieties, the main objective is to develop triploid seedless cultivars. For rootstock, the aim is to cumulate interesting traits in tetraploid hybrids and to improve adaptation to biotic and abiotic stresses. This chapter starts with a review of the recent knowledge acquired on the natural mechanisms of citrus polyploidization and tetraploid meiosis. Chromosome doubling of nucellar cells is frequent in apomictic citrus and results in tetraploid seedling production. Unreduced gametes are also frequently produced, mai…

Genetic diversity and relationships among Italian and foreign almond germplasm as revealed by microsatellite markers

2013

Abstract Italian germplasm is characterized by a wide diversity rapidly developed determining a massive genetic pool of cultivars in several growing areas. On the whole, regions of southern Italy, and in particular Sicily, were considered as one of the main trade routes along which almond was spread throughout the shores of the Mediterranean Sea. In this work, 9 SSR markers have been used to analyze 113 almond cultivars and accessions coming from ex-situ conservation, including most of almond genotypes spread in Sicily and Apulia and foreign cultivars from Mediterranean, American and Australian areas in order to determine the level of genetic diversity within Italian genotypes and elucidate…

Micropropagation of Citrus spp. by Organogenesis and Somatic Embryogenesis.

2013

Citrus spp., the largest fruit crops produced worldwide, are usually asexually propagated by cuttings or grafting onto seedling rootstocks. Most of Citrus genotypes are characterized by polyembryony due to the occurrence of adventive nucellar embryos, which lead to the production of true-to-type plants by seed germination. Tissue culture and micropropagation, in particular, are valuable alternatives to traditional propagation to obtain a high number of uniform and healthy plants in a short time and in a small space. Moreover, in vitro propagation provides a rapid system to multiply the progeny obtained by breeding programs, allows the use of monoembryonic and seedless genotypes as rootstock…

Characterization of five sour orange clones through molecular markers and leaf essential oils analysis.

2006

Five clones of sour orange (Citrus aurantium L.) showing significant morphological differences were selected from our germplasm collection and characterized both by genetic and leaf volatiles analysis. The genetic studies were undertaken by the use of molecular markers developed by PCR-based techniques (ISSR and RAPD), while the leaf essential oil patterns were obtained by chromatographic and mass spectrometric determination. Data obtained suggest that reasonably similar information can be achieved from the two techniques, supporting each other in characterization studies.

Assessing eco-efficiency: A metafrontier directional distance function approach using life cycle analysis

2017

Sustainability analysis requires a joint assessment of environmental, social and economic aspects of production processes. Here we propose the use of Life Cycle Analysis (LCA), a metafrontier (MF) directional distance function (DDF) approach, and Data Envelopment Analysis (DEA), to assess technological and managerial differences in eco-efficiency between production systems. We use LCA to compute six environmental and health impacts associated with the production processes of nearly 200 Spanish citrus farms belonging to organic and conventional farming systems. DEA is then employed to obtain joint economic-environmental farm's scores that we refer to as eco-efficiency. DDF allows us to deter…

Somatic embryogenesis and plant regeneration from pistil transverse thin cell layers of lemon (Citrus limon)

2008

Callus induction, somatic embryogenesis and plant regeneration were obtained in Citrus limon (L.) Burm. (cv. Femminello) from cultures of pistil transverse thin cell layer explants [(t)TCLs]. Explants were cultured on two different media, based on Murashige and Skoog salts and vitamins, supplemented with 500 mg l-1 malt extract (MSI), or 500 mg l-1 malt extract and 13.3 ¼M 6-benzylaminopurine (MSII). Sucrose (146 mM) was used as carbon source. Somatic embryos appeared 3 months after culture initiation from stigma and style (t)TCLs; they were observed at the surface of the (t)TCL-derived callus. Although ovary (t)TCLs showed the highest callus formation, they never differentiated somatic emb…

Biological Properties of a Citral-Enriched Fraction of Citrus limon Essential Oil

2020

Lemon essential oil (LEO) is a well-known flavoring agent with versatile biological activities. In the present study, we have isolated and characterized four citral-enriched fractions of winter LEO. We reported that in murine and human macrophages the pre-treatment with a mix of these fractions (Cfr-LEO) reduces the expression of the pro-inflammatory cytokines TNF-&alpha

Herbicidal activity of Citrus limon essential oil extracted from Sicilian lemon industry

2019

Weeds could reduce yield of annual crops by up to 70%. The main features of these species include high seed production, easily seed dispersal, variable degrees of seed dormancy and high competitivity by rapid seedling growth and higher growth rate than crops. Weed management is a significant challenge faced for crop yield and quality since they compete for water, light, soil nutrients and space. Environmental constraints of crop production systems have stimulated interest in alternative weed management strategies. In fact, the continued use of synthetic herbicides may threaten sustainable agricultural production and has resulted in serious ecological and environmental problems, such as the …

Abstracts from the Fourth International Meeting of ISEV, ISEV2015, Washington, D.C., USA, 23-26 April 2015

2015

Present status of Phytophthora species in the Mediterranean area, especially in relation to citrus

1990

Of the 44 currently accepted species of Phytophthora, 18 have been reported in the Mediterranean area. The status of each is briefly reviewed. On citrus, P. citrophthora and P. nicotianae var. parasitica are mainly responsible for foot rot and gummosis, and in addition P. hibernalis, P. syringae, P. cifricola and P. cactorum for brown rot of fruits. The incidence of these species is closely linked to their temperature requirements. The use of sour orange as a resistant rootstock has long provided satisfactory control of foot rot and gummosis, while chemical treatments are effective against brown rot. However, there are indications that, with changingcultural practices, the resistance of sou…