BENEFICIALTREATMENTS ON PVX AND PVY INFECTED POTATO(SOLANUM TUBEROSUM L.) PLANTS

This study presents the efficiency of some combined techniques (chemo- and electrotherapy) in decreasing the infection level of PVY and PVX infected plants (cv. Roclas). The infected plantlets were exposed to 100 mA for 5, 10 and 20 minutes (electrotherapy), washed, divided into single node cuttings and multiplied in vitro. Chemotherapy was undertaken with ribavirin (RBV) and oseltamivir (OSMV). Solanum tuberosum L.plantlets regenerated were removed from the culture medium, acclimated in green house. The survivor plants were indexed (DAS ELISA, Bioreba, Switzerland). Distinguished virus elimination rates were obtained for all the material infected, using the most severe variants of electrotherapy (100mA/10minutes; 100mA/20 minutes). The highest values were registered in case of PVX infected material

EFFECTS OF SUCROSE MEDIUM CONTENT AND STERILANT TREATMENT ON MICROBIAL CONTAMINATION OF SWEET POTATO CULTURES INITIATED IN VITRO

The main objective of this study was finding solutions for reducing the level of microbial contamination occurred during in vitro cultivation of sweet potato introduced from the ex vitro environment. For this purpose, growth medium variants with different concentrations of sucrose (20 g/L, 30 g/L and 40 g/L) were tested as well as different periods of time during the biological material was in contact with the sterilizing agent: 70% ethanol for 3, 4 and 5 minutes followed by 1% sodium hypochlorite (NaClO) solution for 10, 13 and 16 minutes respectively. Culture medium variants with a sucrose content of 20 g/L and 30 g/L combined with an explants sterilant treatment in 70% ethanol for 4 minutes followed by 1% NaClO for 13 minutes were the most effective in reducing the percentage of microbial contamination

THE INCIDENCE OF POTATO VIRUS Y (NECROTIC STRAINS) IN SEED POTATO GROWN IN SEVERAL ROMANIAN COUNTIES (PRELIMINARY STUDIES)

Protective measures of culture against Potato Virus Y necrotic strains (PVYN) infections, diagnosis and control of this pathogen play an important role in potato seed production technology and multiplication. Also, the choice of resistant varieties to the PVYN infection could be one of the measures recommended for farmers and producers. Surveys during 2 years (2014, 2015), in five main seed potato growing areas of Romania (Brasov, Covasna, Harghita, Cluj, Suceava), for 10 varieties (Christian, Roclas., Riviera, Carrera, Bellarosa, Jelly, Desiree, Red Fantasy, Hermes and Red Lady), revelead significant differences in PVYN incidence.The tests confirmed the PVYN presence in all the regions, with high prevalence of this virus especially for the cultivars Hermes and Carrera and very low spread for for the cultivars the cultivars the cultivars the cultivars the cultivars the cultivars Riviera and Christian

The Growth Response of Several Potato Genotypes (<i>Solanum tuberosum</i> L.) to Induced Water Stress Using Sorbitol and Polyethylene Glycol

The current paper aimed to study the in vitro response of potato genotypes to water stress induced by adding sorbitol and polyethylene glycol in the culture medium. The biological material analysed in the experiment was represented by a Romanian line ‘LP 11-1525/1’ and two isogenic lines ‘LI 101’ and ‘LI 102’. For cultures initiation, the line ‘LP 11-1525/1’ was started from meristems and for the other two genotypes true potato seeds were used. The studied potato genotypes behaved differently depending on the analysed parameters and on the treatment applied for drought tolerance. It was noted that the line ‘LP 11-1525/1’ achieved good results for most of the growth parameters studied, and also the lines derived from true potato seeds behaved well, in some cases even exceeding the line derived from meristems. Of the lines derived from true potato seeds, the best performance was noted for line ‘LI 101-6’ in all the analysed parameters, both on sorbitol and PEG medium. In addition, lines ‘LI 101-7’ and ‘LI 102-4’ achieved good results on both variants of medium used to mediate water stress. Therefore, establishing drought tolerance individuals within populations derived from true potato seeds using sorbitol and polyethylene glycol might be applied

The genotype of potato variety plays an important role for the genetic constitution of somatic hybrids: Solanum tuberosum + late blight resistant S. bulbocastanum

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