Tamar Chipashvili

Grapes are one of the most unstable crops in terms of storage, which is related to its botanical-morphological structure. The aim of our work was to study effect of sodium metabisulfite (SMB) on the most popular Georgina grapevine cultivars “Rkatsiteli” and “Tbilisuri” during Storage. p7 7 kg packed grapes into carton boxes were treated with tree concentration (15g; 25g; 35g) of SMB under cold storage at 0-10C, humidity 90-95% for 120 days to improve storability of grapes varieties: Control- 7kg- no treated grape.

Monitoring of weight loss, dry matter concentration (DMC) sugars and acidity were conducted at the beginning of storage, in the middle (60 days) and at the end of storage (120days). Sugar were measured by Bertrand’s method, dry mass using refractometer, 0.1 N NaOH was used to titrate acidity (g/100ml) to a phenolphthalein end point or, alternatively, to a pH of 8.2.

25g SMB treatments provided the best result to compare others, with weight loss of 6.7% in cultivar “Tbilisuri,” and 8.3% in cultivar “Rkatsiteli,”while weight reduction in control reached 9.8% at the end of storage.

The effect of 15g and 25g SMB was the same on changing the amount of sugars both in the “Tbilisuri” -0/7% (20.8%-20.1%) as in the “Rkatsiteli” -1.2% (20.3%-19.1%).

Significant reductions were observed in acidity at the end of storage using all concentration of SMB. Decrease of acidity was the equally in both grapevine cultivars-2.2% („Tbilisuri“ -5.6%-3.4%; „Rkatsiteli“ - 4, 8%-2,6 %)however it is fully suitable with the amount of sugar, flavor and pulp consistency.

Experimental research allows us to conclude that for long-term storage most effective is to use 25 g SMB tablets per 7 kg of grapes. In addition, no grain loss was observed compared to the other variants, which is one of the most important point in the long-term storage of grapes.

Grapevine storage is still a major concern in Georgia. Metabolic processes results in a considerable reduction in nutritional properties during storage.

The research aim was to study the effect of calcium chloride and eucalyptus extract on the grape cultivar “Italia” during storage. 7kg Grape were treated with different combination of calcium chloride and eucalyptus before storage:; 1.5% calcium chloride+ 1% eucalyptus extract; 2% calcium chloride+ 1% eucalyptus extract. Control_ 7kg Grape.

The level of dry matter, total sugar, acidity and ascorbic acid were evaluated before storage, in the middle and at the end. Dry mass was determined using refractometer, total sugar were measured by Bertrand’s method, titratable acidity (g/100ml) using 0.1 N NaOH to a phenolphthalein end point or to a pH of 8.2, ascorbic acid (mg / 100 ml) by redox titration of 10 ml of I2 in grape juice. 

As a results showed 2% calcium chloride+ 1% eucalyptus extract can improve storability of cultivar “Italia”. The parameters of titratable acid and ascorbic acid were stabile (reduced only 0.6% and 1.4% respectively) during storage compared to others including control (3.1% and 3.3%).

A slight change of dry matter and total sugar was detected in all treated grapes accordingly 0.8% and 0.6%, but loss in control was reached to 1.7% and 2.4%.

Finally, it was revealed that 2% CaCl2 + 1% eucalyptus extract can used as a safe compound during long-tern storage for enhance storability of grape cultivar “Italia”. This is the first storage technology development by the Biotechnology Center in Georgia.

Microbial diseases have been reported in the walnut orchards due to different reasons in recent years in Georgia. For the purpose of walnuts tissue cultures reproduction, it is necessary to determine the optimal type of sterilization of initial material. The aims of this study were determined optimal sterilization type to propagate walnuts cultivars ‘Pedro’, and ‘Chandler’ using tissue culture technique. The initial explants (unimodal micro cuttings with a length between 1 and 1.2 cm) of three cultivars were collected from the young 2-3 years old walnuts orchards, Dzevera, ShidaKartli, Georgia. Two sterilized types were used for in vitro propagation of walnuts: I.1-2% hypochlorite 10-15 min, followed 70 % alcohol -30 min and 3 times sterile distillate water II. 0.1% mercuric chloride 5 min and 3 times sterile distillate water. It was revealed that microbial contamination were 58.97% using 0.1% mercury chloride and relatively high by sodium hipocloride-85.12%. DKW medium was used for in vitro cultivation of walnuts cultivars supplemented with 0.1 mg/L IBA, 1 mg/L BAP and sucrose 3%. The pH of culture medium was adjusted at 5.5 before adding the gelling agent and autoclaving. Micro cuttings were kept at 25±2°C under a 16 h photoperiod. Finally, optimal sterilization types of initial explants (Combination II) was determined. Walnuts cultivars: ‘Pedro’ and ‘Chandler’ were propagated using tissue culture methods first time in Georgia. This study led to develop an effective method for micro propagation of Juglansregia, which enable us to establish new walnuts orchards in Georgia.

Plant viruses can cause loss of yield and quality in a lot of important crops. Symptoms of pathogens are variable depending on the cultivars and virus strain. Selection of resistant potato varieties would reduce the risk of virus transmission and significant economic impact. Other way to avoid reduced harvest yields is regular potato seed production sampling and testing for viral infection. The aim of this study was to determine the occurrence and distribution of viral diseases according potato cultivars for further selection of virus-free material in Georgia. During the summer 2015-2016, 5 potato cultivars (Sante, Laura, Jelly, Red Sonia, Anushka) at 5 different farms located in Akhalkalaki were tested for 6 different potato viruses: Potato virus A (PVA), Potato virus M (PVM), Potato virus S (PVS), Potato virus X (PVX), Potato virus Y (PVY) and potato leaf roll virus (PLRV). A serological method, Double Antibody Sandwich-Enzyme linked Immunosorbent Assay (DAS-ELISA) was used at the laboratory to analyze the results. The result showed that PVY (21.4%) and PLRV (19.7%) virus presence in collected samples was relatively high compared to others. Researched potato cultivars except Jelly and Laura were infected by PVY with different concentrations. PLRV was found only in three potato cultivars (Sante, Jelly, Red Sonia) and PVM virus (3.12%) was characterized with low prevalence. PVX, PVA and PVS virus infection was not reported. It would be noted that 7.9% of samples were containing PVY/PLRV mix infection. Based on the results it can be concluded that PVY and PLRV infections are dominant in all research cultivars. Therefore significant yield losses are expected. Systematic, long-term control of potato viral infection, especially seed-potatoes, must be regarded as the most important factor to increase seed productivity.

The research aim was to determine optimal in vitro condition for propagation different maturity potato cultivars. Potato varieties were collected from in vitro potato collection of Georgian Technical University, Biotechnology Center according to their maturity: Early cultivars: Viviana, Red Sonia, Bellarosa, Vineta, Anushka; Medium early: Donata, Bernina, Madeira, Sante, Laura. Medium late: Brodie, Shepody, Jelly, Carola, Desiree.

The influence of three types of combinations with temperature, humidity, light and photoperiod was studied on all three maturity potato cultivarʼs in vitro development:I. T-23-25° C, H-80%, Lux-5-5500, 16h; II. T-25-27° C, H-75%, Lux-5-5500,16h: III. T-27-29° C, H-70%, Lux-5-5500, 16h;The results were evaluated after 17 days of reproduction. Best in vitro condition for all researched potato varieties was selected for their leave colors, rooting, and shoot formation. All potato cultivars morphological characterization was variable depending on the type of in vitro condition. It was revealed early maturity cultivars had maximum potential for in vitro propagation (5-6 nodes, average rooting 92% and shoot formation 94%) on combination: T-23-25°C, H-80%, Lux-5-5500, 16h. Combination: T-25-27°C, H-75%, Lux-5-5500,16h was best for medium early cultivars (5-6 nods, rooting 89% and shoot formation 90%). The perfect in vitro reproduction of medium late varieties (5-6 nodes, average rooting 87% and shoot formation 82%) was observed on the combination: T-27-29°C, H-70%, Lux-5-5500, 16h.

As it is known, for in vitro developments of early medium and late medium potato cultivars are necessary 22-26 days, but our results were obtained in 17 days. Finally, optimal in vitro condition for propagation different maturity potato cultivars was defined.

n this study we focused on in vitro potato regeneration under different hormonal (auxin/cytokine) treatment with combination of sucrose in three potato varieties, “Nevsky, Riviera, Zefira”. Three parameters were observed in response to treatment, number of shoots development, size of shoots, and root length. In vitro tissue culture propagation of three potato cultivars (Solanum tuberosumL.) “Nevsky”, Zefira” and “Riviera” were studied on modified MS medium supplemented with hormones (IBA/BAP) concentration: MS + 30g/l sucrose (6% MS medium), 6%MS medium +1mg/l BAP + 0,05mg/l IBA and 6% MS medium +1mg/l BAP + 0,1mg/l IBA. Morphological characterization of all three in vitro potato cultivars on modified MS medium was variable depending on varieties.It was revealed that high concentration of IBA has negative effect on plants development, respectively 6% MS medium + 1mg/l BA + 0,1mg/l IBA was not optimal neither cultivars of potato. According to the results cultivars Zefira” and “Riviera” had maximum potential for in vitro rooting ( correspondingly: 82.97% and 100%) and shoots (100% and 87.34%) formation on 6% MS medium + 1mg/l BA + 0,05mg/l IBA, but “Nevsky” gave maximum development (rooting-82% and shoot formation -87%) on 6% MS medium.

Potato (Solamum Tuberosum L.) is one of the most popular crop in Georgia. The climatic conditions of Georgia enable us to produce several varieties of potato cultivars. The research goal was the development of seed production methods from apical meristem in order to get super elite seed. Three potato varieties were selected for the experiment: “Sante”, “Amoroza” and “Nevsky”. It is the first time that potato super elite seed was produced from strengthened in vitro plants (in the laboratory condition –instead of greenhouse) in Georgian regions: Akhaltsikhe and Tsalka. It was releaved that potato cultivar Nevsky characterized high elite seed Production ability (5ton), Sante showed relatively low Harvest (2ton) in Tsalka, other results were the same among Georgian two regions Akhaltsikhe and Tsalka. In this way, World-renowned elite seed making full cycle modification was performed in the conditions of Georgia: laboratory-greenhouse-open field was replaced by laboratory-laboratory (plants strengthen)-open field.

Potato is the most widespread culture, in terms of consumptionpotato is in the second place after cereals.Nowadays Georgia has no potato seed production. Healthy seed is the guarantee of product quality. The research goal was the selection of potato species introduced from abroad and are more or less adapted to the environmental conditions of Georgia, acceptance-strengthen in vitro tube plants and their translocation in semi-open-field without greenhouse in order to get super-super elite followed by reproducing we can get potato elite seed, selected three types of potato cultivars (“Amoroza”, “Nevsky” and “Sante”), they are characterized with high productivity and rush at consumer marketReceiving elite seed full cycle modification known all over the world was done in the conditions of Georgia. Particularly the full cycle: laboratory-greenhouse-open field was replaced by laboratory (phytotrone)-laboratory(plants strengthen))-open field. Georgian farmers received the local production elite seed by our developed technology.

Doctoral Thesis Referee

Master Theses Supervisor

Doctoral Thesis Supervisor/Co-supervisor

Scientific editor of monographs in foreign languages

Scientific editor of a monograph in Georgian

Editor-in-Chief of a peer-reviewed or professional journal / proceedings

Review of a scientific professional journal / proceedings

Member of the editorial board of a peer-reviewed scientific or professional journal / proceedings

Participation in a project / grant funded by an international organization

Participation in a project / grant funded from the state budget

Patent authorship

Membership of the Georgian National Academy of Science or Georgian Academy of Agricultural Sciences

Membership of an international professional organization

Membership of the Conference Organizing / Program Committee

National Award / Sectoral Award, Order, Medal, etc.

Honorary title

Monograph

Handbook

Research articles in high impact factor and local Scientific Journals

Publication in Scientific Conference Proceedings Indexed in Web of Science and Scopus