Search results for "Microspore"

In vitro anther culture of sweet orange (Citrus sinensis L. Osbeck) genotypes and of a C. clementina × C. sinensis 'Hamlin' hybrid

2014

Citrus, and particularly sweet oranges, are very recalcitrant to anther culture. In this paper it was evaluated for the first time the response of 27 genotypes of Citrus sinensis and of one hybrid C. clementina × C. sinensis, to in vitro anther culture. Ten genotypes of sweet oranges showed embryogenic callus induction, mostly blood sweet oranges genotypes, such as Tarocco, Moro and Sanguinelli. In vitro microspore developmental switches from the gamethophytic to the sporophytic pathway were shown by DAPI staining in microspores of these responsive genotypes, after 10 months in culture. However, microsatellite marker analyses showed that these calli were heterozygous. The flow-cytometric an…

The phosphorylated pathway of serine biosynthesis is essential both for male gametophyte and embryo development and for root growth in Arabidopsis.

2013

This study characterizes the phosphorylated pathway of Ser biosynthesis (PPSB) in Arabidopsis thaliana by targeting phosphoserine phosphatase (PSP1), the last enzyme of the pathway. Lack of PSP1 activity delayed embryo development, leading to aborted embryos that could be classified as early curled cotyledons. The embryo-lethal phenotype of psp1 mutants could be complemented with PSP1 cDNA under the control of Pro35S (Pro35S:PSP1). However, this construct, which was poorly expressed in the anther tapetum, did not complement mutant fertility. Microspore development in psp1.1/psp1.1 Pro35S:PSP1 arrested at the polarized stage. The tapetum from these lines displayed delayed and irregular devel…

Early in vitro development of isolated microspores of four Sicilian olive cultivars.

2015

Nowadays there is a great interest in the advancement of the studies on gametic embryogenesis in olive, as a method for obtaining homozygous material, due to the enormous effort and relevance in its genome sequencing and gene mapping. In this study, in vitro isolated microspore culture of four Sicilian olive cultivars (‘Biancolilla napoletana’, ‘Nocellara del Belice’, ‘Tonda Iblea’ and ‘Verdello’) has been carried out, investigating the influence of two polyamines (putrescine and spermidine) and of two medium compositions on pollen embryogenesis induction. During in vitro development, different structural features have been observed: uninucleated microspores, with no development, binucleate…

Advancement on isolated microspore culture in Citrus clementina Hort. ex Tan., cvs. Monreal Rosso and Nules.

2013

Coltura in vitro di microspore isolate per il miglioramento genetico di Olea europaea L.

2013

Gli aploidi (piante con un numero gametofitico di cromosomi nello sporofito: n invece di 2n) ed i doppio-aploidi (aploidi che hanno raddoppiato il numero di cromosomi spontaneamente o in maniera indotta) trovano numerose applicazioni nel miglioramento genetico vegetale, ed in particolare, nella mutagenesi, nella selezione in vitro, nella trasformazione, nell’utilizzo della variabilità gametoclonale ed anche nel sequenziamento del genoma e negli studi di genomica funzionale. Pertanto, essi costituiscono uno strumento biotecnologico particolarmente interessante nel miglioramento genetico delle piante. Ai fini dell’ottenimento dell’omozigosi nell’olivo, come in tutte le piante arboree, caratte…

Study on isolated microspore culture in Citrus sinensis Osbeck cv. Moro, a blood orange cultivar].

2014

Microspore embryogenesis inCitrusand other fruit crops

2017

Conventional methods, involving several generations of selfing, are not applicable to produce homozygous lines in Citrus as well as in the other fruit crops, due to the high heterozygosity of the genomes, the long duration of the generation cycle, the large size, and, often, the self-incompatibility. For this reason, there is no different way to obtain homozygosity in this kind of plants than “gametic embryogenesis” that allows the development of haploids (Hs, plants with gametophytic chromosome number) and doubled haploids (DHs, haploids that have undergone chromosome duplication) from heterozygous parents in a single step. Therefore, gametic embryogenesis is increasingly object of res…

Gametic embryogenesis through isolated microspore culture in mandarin (Citrus reticulata Blanco), Mandarino Tardivo Di Ciaculli: effect of meta-Topol…

2016

Haploid technology, allowing the single-step development of complete homozygous genotypes from heterozygous plants through gametic embryogenesis, has already an enormous impact on breeding programs of many important crops. Microspore embryogenesis can be carried out through in vitro culture of anther or isolated microspore. Experiments have been carried out via isolated microspore culture in Citrus reticulata (Blanco), Mandarino Tardivo di Ciaculli, investigating the influence of two culture media, of two plant growth regulator types and of two temperature treatments applied before the culture or just after the culture. After ten months of culture, for all the media tested, different struct…

STUDY ON GAMETIC EMBRYOGENESIS VIA IN VITRO ANTHER AND ISOLATED MICROSPORE CULTURE IN FRUIT CROPS

2014

Fruit breeding is mainly based on both conventional (hybridization, mutation and selection) or biotechnological methods (somatic hybridization, genetic transformation and haploid production). The genetic improvement through the conventional methods is limited by many factors such as fruit trees long juvenile period, high heterozygosity, large size and sexual incompatibility. Haploids and doubled haploids, obtained through gametic embryogenesis have a potential use in fruit crops genetic improvement. The change of the microspores fate from the normal gametopytic pathway towards the sporophytic induction is affected by numerous factors. Genotype, medium composition and stress were considered …

Preliminary Results on the Effect of Magnetic Fields on Anther Culture and Pollen Germination of Citrus clementina Hort. ex Tan.

2003

Exposure to electromagnetic fields seems to modify the biological behaviour of seeds, roots, pollen grains and buds of several plants. This procedure has been also suggested as a tool to improve the utilization of plant species (Firetto et al., 2000, 2001, Petruszewski S., 1996). Since the first haploid embryogenic calli production and plantlet regeneration by anther culture of C. clementina Hort. ex Tan. 'Nules' was reported (Germany et al., 1994), several studies have been carried out to improve both the frequency of microspore embryogenesis and the percentage of plantlet regeneration. To enlarge the number of respondent genotypes and to improve the induction rate (the frequency of pollen…