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SCIENTIFIC WORKS OF THE LITHUANIAN INSTITUTE OF HORTICULTURE AND LITHUANIAN UNIVERSITY OF AGRICULTURE. SODININKYSTĖ IR DARŽININKYSTĖ. 2008. 27(2).

Small berry research according to COST 863 Action

Audrius Sasnauskas, Rytis Rugienius, Tadeušas Šikšnianas, Nobertas Uselis, Laimutis Raudonis, Alma Valiuškatė, Aušra Brazaitytė, Pranas Viškelis, Marina RubinskienėLithuanian Institute of Horticulture, Kauno 30, LT-54333 Babtai, Kaunas distr.,

Lithuania, e-mail: A.Sasnauskas@lsdi.lt

Strawberry and blackcurrant cultivars with promising hybrids according to COST 863 Action were investigated at the Lithuanian Institute of Horticulture.

Strawberry cultivars ‘Dangė’, ‘Saulenė’ and ‘Elsanta’ had the biggest number of crowns, leaves and runners, while ‘Elsanta’ and ‘Kent’ had the biggest amount of flower clusters and berries. The most productive were strawberries of ‘Elsanta’ and ‘Kent’. ‘Venta’ and ‘Rosie’ had highest average berry size in strawberry collection. The best appearance was of ‘Rosie’ and J973854, berry firmness – 005004 and ‘Rosie’, best taste of 64 and ‘Venta’. ‘Dangė’ and ‘Honeoye’ strawberries distinguished themselves with intensive photosynthesis at period of full blooming.

The highest bushes had blackcurrant cultivars ‘Titania’ and ‘Ben Lomond’, the lowest – ‘Gagatai’ and ‘Almiai’. The biggest bush width had ‘Öjebyn’ and ‘Ben Nevis’, narrow – ‘Ben Tron’, ‘Ben Alder’ and ‘Ben Tirran’. Highest average yield was received from ‘Ben Tirran’, ‘Titania’ and ‘Öjebyn’. ‘Joniniai’, ‘Vyčiai’ and ‘Laimiai’ had the biggest berries. Biological efficiency of fungicide Signum WG against blackcurrant powdery mildew (Sphaerotheca mors-

uvae (Schw.) Berk. et Curt), leaf spot (Mycosphaerella ribis Lind.) and insecticide-acaricide Envidor 240 SC against two-spotted spider mite (Tetranychus urticae Koch.) was investigated. Applying the rates of 0.5–1.0 kg/ha four times per vegetation Signum WG effectively prevented powdery mildew and leaf spot. Applying the rates of 0.3–0.6 l/ha three times per vegetation Envidor 240 SC was effective against two-spider mite.

Sequence specific marker (SCAR) associated with strawberry resistance to red stele (Phytophthora fragariae) Rpf1 gene was developed after cloning and sequencing of RAPD marker. Using SCAR marker occurrence of Rpf1 gene in different strawberry cultivars and seedlings were estimated. According to these data, cultivars ‘Redgauntlet’, ‘Anapolis’, ‘Tristar’, ‘Dangė’ and promising hybrids have this gene. Expression of COR47 gene homologues in strawberry was evaluated during cold acclimation in vitro. It was established that maximal accumulation of this gene transcript occurs on 30th day of cold acclimation.

Key words: strawberry, blackcurrant, trial evaluation, physiology, pest and diseases, markers.

Introduction. The COST 863 Action has a new and advanced approach to promote the integration of research, production systems, quality control, added nutritional value and consumer acceptance. The action organized with a new integrated approach: from laboratory via farm to consumer table.

The importance of this COST Action on berry research is supported by the large

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group of countries involved in the cultivation of berries (Faedi, 2004; Karhu, Hytönen, 2006; Spak et al., 2006; Özuygur et al., 2006; Rugienius, Sasnauskas, 2006). This will improve co-operation between research programmes, including high level science and technology, to develop European berry production system characterized by a reduction of chemical inputs that are harmful to the environment along with lower production costs (reduced labour costs) and increased benefits for the consumer (healthy fruits).

The aim of this study was to investigate small berry cultivars, efficiency of fungicide and insecticide, photosynthesis period of full blooming, to estimate SCAR marker occurrence of Rpf1 gene in different strawberry cultivars and seedlings and expression of COR47 gene homologues in strawberry during cold acclimation in vitro.

Object, methods and conditions. S t r a w b e r r y t r i a l s. The following strawberry cultivars were compared in unheated plastic greenhouse: ‘Elsanta’, ‘Kent’, ‘Elkat’, ‘Honeoye’, ‘Saulenė’ and ‘Dangė’. Strawberries were established with frigo plants in early spring. Peat-filled plastic sacks were used as substrate. Sacks were located on shelving of 1.3 m height. Plant growth (units/plant), development (units/plant) and yield (kg/m2) were evaluated. The trial was established in four replications. Each plot contained 21 plants.

The following strawberry cultivars were investigated in the collection: ‘Anapolis’, ‘Krymsakaja Remontantnaja’, ‘Wega’, ‘Sara’‚ ‘Venta’‚ ‘Rosie’, F. virg glauca, hybrid clones 005004 (‘Selen’ × (F. chiloensis D. N. × ‘Tribute’)), J973854 (K88-4 × ‘Mohawk’), 64 (‘Guardian’ × ‘Pegasus’). The trial was established in four replications. Each plot contained 5 plants. Beginning of yield (month, day), berry size (scores), appearance (scores), firmness (scores) and taste (scores) were evaluated. Scores 1–9 were used (1 – lowest, 9 – highest).

Assimilation area was measured with leaf area measurer CI-202 (CID Inc., USA). Plant dry weight was established drying at the temperature of 105 °C. Photosynthesis intensity was measured using PorTable Photosynthesis System (CI-310). Measurements were made during flowering.

Polymorfic primer OPO16 suggested by Van de Weg, (1997) was used for PCR in aim to develop SCAR marker of strawberry red stele (Phytophthora fragariae) resistance gene Rpf1.

Total DNA was isolate from strawberry cultivars and hybrid clones 005001-2 (‘Selen’ × ‘Tristar’) ‘Anapolis’, ‘Redgauntlet’, 940101 (‘Guardian’ × ‘Pegasus’)‚ ‘Elsanta’‚ ‘Selen’‚ ‘Tristar’ using CTAB protocol.

For COR47 gene expression investigations total RNA was isolated from strawberry plants incubated at + 2 °C temperature for 1, 2, 4, 8 and 14 days. Copy DNA of COR47 gene was synthesized using RevertAid™ H Minus First Strand cDNA Synthesis Kit (Fermentas).

Blackcurrant trials. The following blackcurrant cultivars were compared: ‘Joniniai’, ‘Kupoliniai’, ‘Zagadka’, ‘Gagatai’, ‘Almiai’, ‘Vyčiai’, ‘Laimiai’, ‘Öjebyn’, ‘Kriviai’, ‘Titania’, ‘Pilėnai’, ‘Ben Tron’, ‘Ben Lomond’, ‘Ben Alder’, ‘Ben More’, ‘Ben Nevis’ and ‘Ben Tirran’.

The bushes were planted at the distance of 3 × 0.6 m. The trial was established in tree replications. Each plot contained 3 bushes. In the trial there was established bush height and width (cm), berry yield (kg/bush) and berry size (g). Fungicides were sprayed four times: until blooming, two times after blooming and after harvesting.

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Insecticides were sprayed three times: until blooming, after blooming and after harvesting. Sprayer STIHL SR 400 was used for spraying, water volume – 250 l ha-1. Growing, fertilizing, weed control, soil cultivation, pruning and care of blackcurrant cultivars were maintained as recommended for commercial orchards (Intensyvios uoginių augalų auginimo technologijos, 2002).

Data were elaborated by analysis of variance, followed by Fisher’s Protected LSD and Duncan’s Multiple-Range t-test at P = 0.05.

Results. S t r a w b e r r y g r o w t h v i g o u r. In both years of investigation cv. ‘Dangė’ (3.8 units) was distinguished for the highest crown per plant. Within the range of tested cultivars ‘Elsanta’ (22.8 unts) had more leaves the same as cv. ‘Dangė’ (6.3 units) and ‘Saulenė’ (3.7 units) runners per plant (Table 1).

Table 1. Strawberry growth vigour (units/plant)1 lentelė. Braškių kerelių augumas, vnt./aug.

Babtai, 2003–2004

S t r a w b e r r y d e v e l o p m e n t. ‘Elsanta’ (2.7 units) had more inflorescences in comparison with other investigated cultivars (Table 2). ‘Kent’ (2 units) and ‘Elkat’ (1.9 units) had medium, while ‘Dangė’ (0.6 units) had the smallest inflorescences per plant over two years.

During the years of investigations the highest berries produced cv. ‘Elsanta’ (19.1 units). The lowest berries were of cvs. ‘Dangė’ (4 units) (Table 2).

Table 2. Strawberry development2 lentelė. Braškių kerelių išsivystymas

Babtai, 2003–2004

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Y i e l d o f s t r a w b e r r y c u l t i v a r s. The highest yield was from ‘Elsanta’ (2.41 kg/m2) and ‘Kent’ (2.25 kg/m2). ‘Elkat’ (1.56 kg/m2) and ‘Honeoye’ (1.18 kg/m2) were more productive than ‘Dangė’ (0.40 kg/m2) and ‘Saulenė’ (0.80 kg/m2).

Table 3. Strawberry yield 3 lentelė. Braškių derlius

Babtai, 2003–2004

S t r a w b e r r y c u l t i v a r e v a l u a t i o n i n c o l l e c t i o n. F. virg glauca,

‘Krymskaja remontantnaja’, J973854, ‘Wega’ and ‘Venta’ ripened early, while 005004 – latest (Table 4). The biggest berries produced cvs. ‘Venta’ and ‘Rosie’ (11 g), smallest – F. virg glauca (3.5 g). The berries of cvs. ‘Rosie’ (10 scores) and J973854 (9.5 scorers) produced extremely good appearance berries; 005004 and ‘Rosie’ (9.5 scorers) – berries of good firmness; 64 and ‘Venta’ (9.5 scorers) – berries of very good taste.

Table 4. Strawberry cultivar evaluation in collection

4 lentelė. Braškių veislių tyrimas kolekcijojeBabtai, 2007

B u s h h e i g h t a n d w i d t h c h a r a c t e r i s t i c s a n d b e r r y q u a l i t y p a r a m e t e r s o f b l a c k c u r r a n t s. The highest bushes had blackcurrant cultivars ‘Titania’ (130 cm) and ‘Ben Lomond’ (125 cm), the lowest – ‘Gagatai’ (90 cm) and ‘Almiai’ (91.7 cm) (Table 5).

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Table 5. Bush height and width characteristics and berry quality parameters5 lentelė. Juodųjų serbentų uogakrūmių augumas ir uogų kokybės parametrai

Babtai, 2007

The biggest bush width had ‘Цjebyn’ (165 cm) and ‘Ben Nevis’ (168.3 cm); ‘Ben Tron’ (96.7 cm), ‘Ben Alder’ (103.3 cm) and ‘Ben Tirran’ (105 cm) were the narrowest. ‘Joniniai’ (140.7 g), ‘Vyčiai’ (129.5 g) and ‘Laimiai’ (124.5 g) had the biggest berries, while ‘Öjebyn’ (68.7 g) and ‘Ben Alder’ (70.4 g) – smallest. ‘Joniniai’ (1.97 g) and ‘Vyčiai’ (1.88 g) distinguished themselves with the biggest berry size; ‘Titania’ (0.23 g) and ‘Kupoliniai’ (0.29 g) berries were the smallest.

Y i e l d o f b l a c k c u r r a n t c u l t i v a r s. During the year of investigation the late spring frost at the beginning of bloom injured blossoms and average yield was 0.73 kg/bush (Fig.1). The yield of blackcurrant cultivars ranged from 0.2 to 1.86 kg/bush. ‘Ben Tirran’ (1.86 kg/bush), ‘Titania’ (1.59 kg/bush) and ‘Öjebyn’ (1.21 kg/bush) produced a higher yield. Cvs. ‘Ben Alder’ (0.88 kg/bush), ‘Kriviai’ (0.86 kg/bush), ‘Zagadka’ (0.81 kg/bush) and ‘Almiai’ (0.76 kg/bush) produced higher yield in comparison with the average of investigated cultivars. Cvs. ‘Vyčiai’ (0.2 kg/bush), ‘Laimiai’ (0.25 kg/bush), ‘Pilėnai’ (0.26 kg/bush) and ‘Gagatai’ (0.27 kg/bush) had the lowest yield.

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Fig. 1. Yield of blackcurrant cultivars, kg/bush1 pav. Juodųjų serbentų veislių derlius, kg/krūmo

Babtai, 2007

P h o t o s y n t h e s i s i n t e n s i t y. ‘Dangė’ and ‘Honeoye’ strawberries distinguished themselves with intensive photosynthesis at period of full blooming; while in leaves of ‘Elsanta’ and ‘Saulenė’ dominate breathing (Fig. 2).

Fig. 2. Net photosynthesis intensity at period of full blooming (PAR average – 698 µmol m-2 s-1; air temperature average – 26 °C)

2 pav. Neto fotosintezės intensyvumas braškių gausiausio žydėjimo metu (vidutinė FAR – 698 µmol m-2 s-1; vidutinė oro temperatūra – 26 °C)

Babtai, 2004

B l a c k c u r r a n t p r o t e c t i o n f r o m d i s e a s e s a n d p e s t. Signum WG 1.0, 0.5 kg/ha applied 4 times during growing season (until blooming,

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after blooming and after harvesting) was effective against diseases. Rate of fungicide Signum WG 1.0 kg/ha efficiency of preparation was as follows: against powdery mildew – 90.5 %, against leaf spot – 91.6 %. Lower rate of fungicide Signum WG 0.5 kg/ha reduced powdery mildew efficiency to 88.4 %, against leaf spot – 88.7 %. Efficiency of standard fungicide Candit 0.2 kg/ha was also high: against powdery mildew – 89.5 %, against leaf spot – 90.9 %. There were found 95 % powdery mildew symptoms and 70 % leaf spot symptoms on leaves in unsprayed plots (Tables 6–7).

Table 6. Impact of fungicide Signum on powdery mildew6 lentelė. Fungicido Signum efektyvumas nuo miltligės

Babtai, 2004–2005

Table 7. Impact of fungicide Signum on leaf spot7 lentelė. Fungicido Signum efektyvumas nuo šviesmargės

Babtai, 2004–2005

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Rate of insecticide-acaricide Envidor 240 SC 0.3 l/ha efficiency of preparation against two-spotted spider mite ranged between 63.8–100 % (Table 8). Envidor 240 SC 0.6 l/ha and 0.3 l/ha applied 2 months after spraying efficiency was 87.7–83.4 %, while standard insecticide Karate 0.5 l/ha efficiency against two-spotted spider mite was only 63.9 %. In both treatments with Envidor 240 SC 0.6 l/ha and 0.3 l/ha number of two-spotted spider mite on 1 leaf not statistically differences were found.

Table 8. Efficiency of insekticide-acaricide Envidor 240 SC against two-spotted spider mite8 lentelė. Insekticido akaricido Envidoro 240 g/l efektyvumas nuo paprastųjų voratinklinių erkių

Babtai, 2004–2005

M o l e c u l a r i n v e s t i g a t i o n s o f s t r a w b e r r y. Using OPO16 polymorfic primer, DNA fragment specific for red stele susceptible strawberry was isolated. This DNA fragment was cloned to pTZ57 plasmid and sequenced. DNA sequence specific (SCAR) primers were selected. Newly developed SCAR marker allows excluding susceptible genotypes lacking of red stele resistance gene Rpf1. According PCR data, genotypes ‘Redgauntlet’, ‘Anapolis’; ‘Tristar’, ‘Dangė, 005001; 005002 have Rpf1 gene, other genotypes: ’Honeoye’; ‘Elsanta’, Venta’, ‘Kama’; 940101; ‘Selen’; ‘Elkat’ and ‘Senga Sengana’ – have not (Fig. 3).

Homologues of Arabidopsis thaliana (L.) Heynh cold response (COR47) gene were isolated from different fruit and berry plants. Expression of those genes during acclimation was investigated. It was established that maximal accumulation of COR47 transcript occurs 30 after start of cold acclimation (Fig 4).

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Fig. 3. Strawberry electrophoregram after PCR using newly developed Rpf1 gene SCAR marker (size 400 bp)

3 pav. Braškių DNR elektroforegrama po PGR, taikant naujai išskirtа geno Rpf1 žymenį (dydis 400 bp) M – GeneRulerTM 1kb DNA Ladder, 1 – ‘Honeoye’; 2 – ‘Redgauntlet’,

3 – ‘Elsanta’, 4 – ‘Venta’, 5 – ‘Kama’; 6 – ‘Anapolis’; 7 – ‘Tristar’; 8 – 940101; 9 – ‘Selen’; 10 – 005001; 11 – 005002; 12 – ‘Elkat’, 13 – ‘Senga Sengana’; 14 – ‘Dangė’.

Fig. 4. Dynamics of cold responsive COR47 gene expression in strawberry during cold acclimation in vitro

4 pav. Šalčio indukuojamo COR47 geno homologų transkripcijos kitimas užsigrūdinimo metu braškėse in vitro. 1, 3, 5, 7, 9, 11 – ‘Melody’. 2, 4, 6, 8, 10, 12 – ‘Holiday’.

1–2 – before acclimation/ augalai prieš grūdinimа; 3–4 – cold acclimated for 6 days/ 6 dienas grūdinti augalai; 5–6 – 12 days/ 12 dienų;

7–8 – for days 18/ 18 dienų, 8–9 – 24 days/ 24 dienas; 11–12 – 30 days/ 30 dienų; 13 – O‘GeneRulerTM 1 kb DNA Ladder.

Discussion. Small berry yield and quality parameter has recently become more and more important for the scientists, consumers and producers (Faedi et al., 2002; Roudeillac, Trajkovski, 2004; Sousa et al., 2008; Voca et al., 2008). Our data show that different genotypes might have different strategy for these characters. During the years of investigation, strawberry cvs. ‘Elsanta’, ‘Kent’ and blackcurrant cvs. ‘Ben Tirran’, ‘Titania’, ‘Öjebyn’ produced the highest yield. The investigation shows that ‘Elsanta’ and ‘Kent’ had the biggest amount of flower clusters and berries in peat-filled plastic sacks like ‘Venta’ and ‘Rosie’ for the same investigated character in the collection. On the other hand, Lithuanian blackcurrant cultivars ‘Joniniai’, ‘Vyčiai’ and ‘Laimiai’ had the biggest berries in comparison with introduced cultivars. Appearance, taste and firmness are quality attribute. Results of organoleptic evaluation show that berries of

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cvs. ‘Rosie’ and J973854 were of extremely good appearance; 005004 and ‘Rosie’ – of good firmness; 64 and ‘Venta’ – of very good taste.

New chemicals help in blackcurrant pests and diseases control (Rašinskienė, Šikšnianas, 1995; Locke, Koomen, 1999; Raudonis, 2002; Locke et al., 2003; Worley, 2003). The investigation shows that applying the rates of 0.5–1.0 kg/ha four times per vegetation Signum WG effectively prevented powdery mildew and leaf spot. On the other hand, applying the rates of 0.3–0.6 l/ha three times per vegetation Envidor 240 SC was effective against two-spotted spider mite.

Biotechnological methods (in vitro, marker assisted selection) helps to speed up breeding process, screen gene pool and evaluate of fruit and berry plants holding valuable traits and also investigate biological mechanisms of disease and cold resistance.

Conclusions. 1. Strawberry cultivars ‘Dangė’, ‘Saulenė’ and ‘Elsanta’ had the biggest number of crowns, leaves and runners.

2. ‘Elsanta’ and ‘Kent’ had the biggest amount of flower clusters and berries. 3. Most productive were strawberries of ‘Elsanta’ and ‘Kent’.4. The biggest fruits produced cvs. ‘Venta’ and ‘Rosie’. The berries of cvs. ‘Rosie’

and J973854 were of extremely good appearance; 005004 and ‘Rosie’ – of good firmness; 64 and ‘Venta’ – of very good taste.

5. The highest bushes had blackcurrant cultivars ‘Titania’ and ‘Ben Lomond’, the lowest – ‘Gagatai’ and ‘Almiai’. The biggest bush width had ‘Öjebyn’ and ‘Ben Nevis’; ‘Ben Tron’, ‘Ben Alder’ and ‘Ben Tirran’ were the narrowest. Highest average yield was received from ‘Ben Tirran’, ‘Titania’ and ‘Öjebyn’. ‘Joniniai’, ‘Vyčiai’ and ‘Laimiai’ had the biggest berries.

6. ‘Dangė’ and ‘Honeoye’ strawberries distinguished themselves with intensive photosynthesis at period of full blooming.

7. Applying the rates of 0.5–1.0 kg/ha four times per vegetation Signum WG effectively prevented powdery mildew and leaf spot. Applying the rates of 0.3–0.6 l/ha three times per vegetation Envidor 240 SC was effective against two-spotted spider mite.

8. Strawberry cultivars ‘Redgauntlet’, ‘Anapolis’, ‘Tristar’, ‘Dangė’ and promising hybrids have Rpf1 gene.

9. Maximal accumulation of COR47 gene transcript occurs on 30th day of cold acclimation.

Acknowledgement. We’re grateful to Agency for International Science and Technology Development Programmes in Lithuania for help and support realizing COST 863 Action.

Gauta 2008 04 14

Parengta spausdinti 2008 04 30

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2. Faedi F. 2004. COST: Past, Present, Future. Acta Horticulturae, 649: 21–24.3. Intensyvios uoginių augalų auginimo technologijos. 2002. N. Uselis. (sudaryt.).

Lietuvos Sodininkystės ir daržininkystės institutas, Babtai.4. Karhu S. T., Hytönen T. P. 2006. Nursery plant production controlled by

prohexadione-calcium and mechanical treatments in strawberry cv. ‘Honeoye’. The Journal of horticultural science and biotechnology, 81(6): 937–942.

5. Locke T., Koomen I. 1999. Can spore trapping be of help in black currant mildew control? Acta Horticulturae, 505: 333–336.

6. Locke T., Bobbin P., Atwood J., Owen J. 2003. Effect of strobilurin fungicides on disease control and yield in blackcurrants. Acta Horticulturae, 585: 394–396.

7. Özuygur M., Paydaŗ K. S., Kafkas E. 2006. Investigation on yield, fruit quality and plant characteristics of some local, European and American strawberry varieties and their hybrids. Agriculturae conspectus scientificus, 71(4): 175–180.

8. Raudonis L. 2002. Monitoring of harmful insects and mites of strawberries. Sosininkystė ir daržininkystė, 21 (4): 102–110.

9. Rašinskienė A., Šikšnianas T. 1995. Juodųjų ir raudonųjų serbentų veislių parinkimas mechanizuotam uogų skynimui. Mokslo straipsnių rinkinys. Sodo augalų selekcijos uždaviniai ir perspektyvos. Babtai, 59–66.

10. Roudeillac P., Trajkovski K. 2004. Breeding for fruit quality and nutrition in strawberries. Acta Horticulturae, 649: 55–60.

11. Rugienius R., Sasnauskas A. 2006. Braškių veislių tyrimas Lietuvoje pagal tarptautinę COST 863 programą. Sodininkystė ir daržininkystė, 25(4): 43–53.

12. Sousa M. B., Curado T., Trigo M. J., Vasconcelos F. N., Nunes T. 2008. Strawberry quality: effect of cultivars, harvest date and storage. Book of abstracts VI international strawberry symposium. ISHS. Huelva, Spain. 3–7 March, 399.

13. Spak J., Navrátil M., Karelová R., Pribylová J., Válová P., Kucerová J., Kubelková D., Fialová R., Spaková V. 2006. Occurrence, symptom variation and yield loss caused by full blossom disease in red and white currants in the Czech Republic. Crop protection 25: 446–453.

14. Voca S., Duralija B., Družic J., Dobričevic N., Dragovic-Uzelac V. 2008. Quality of late harvest strawberry varieties in Croatia. Book of abstracts VI international strawberry symposium. ISHS. Huelva, Spain. 3–7 March, 415.

15. Worley J. 2003. Fungicide on trial how Signum has performed for soft fruit grower. Bulletin OILB/SROP, 140(30): 22–29.

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SODININKYSTĖ IR DARŽININKYSTĖ. MOKSLO DARBAI. 2008. 27(2).

Uogininkystės tyrimai pagal COST 863 programą

A. Sasnauskas, R. Rugienius, T. Šikšnianas, N. Uselis, L. Raudonis, A. Valiuškatė, A. Brazaitytė, P. Viškelis, M. Rubinskienė

Santrauka

Lietuvos sodininkystės ir daržininkystės institute pagal tarptautinę COST 863 programą tirtos braškių bei juodųjų serbentų veislių ir hibridinių klonų biologinės ir ūkinės savybės.

‘Dangės’, ‘Saulenės’ ir ‘Elsantos’ veislių braškės pagal ragelių, lapų ir ūsų skaičių augo vešliausiai. Pagal žiedynų ir uogų skaičių geriausiai išsivysčiusios buvo braškės ‘Elsanta’ ir ‘Kent’. Derlingiausios braškės ‘Elsanta’ ir ‘Kent’. Braškių kolekcijoje pagal didžiausiа vidutinę uogų masę išsiskyrė ‘Venta’ ir ‘Rosie’. Gera uogų išvaizda pasižymėjo ‘Rosie’ ir J973854; uogų kietumu – 005004 ir ‘Rosie’; geru uogų skoniu – selekcinis klonas 64 ir ‘Venta’. Gausiausio braškių žydėjimo metu intensyviausia fotosintezė vyko ‘Dangės’ ir ‘Honeoye’ braškių lapuose.

Palyginus skirtingas juodųjų serbentų veisles nustatyta, kad aukščiausi užauga ‘Titania’ ir ‘Ben Lomond’, o žemiausi – ‘Gagatai’ bei ‘Almiai’ veislių serbentų krūmai. Plačiausiais krūmais išsiskyrė ‘Öjebyn’ ir ‘Ben Nevis’ veislės, siauriausiais – ‘Ben Tron’, ‘Ben Alder’ bei ‘Ben Tirran’ juodųjų serbentų krūmai. Gausiausiai derėjo juodųjų serbentų veislių ‘Ben Tirran’, ‘Titania’ ir ‘Öjebyn’ uogakrūmiai. Stambiausias uogas išaugino ‘Joniniai’, ‘Vyčiai’ ir ‘Laimiai’. Juodųjų serbentų veislės ‘Joniniai’ bei ‘Vyčiai’ išsiskyrė didžiausiomis uogomis. Fungicidas Signum 334 g/kg v. d. g. 0,5–1,0 kg/ha yra efektyvus juodųjų serbentų apsaugai nuo miltligės (Sphaerotheca mors-uvae (Schw.) Berk. et Curt) ir šviesmargės (Mycosphaerella

ribis Lind.) purškiant keturis kartus per vegetacijа: prieš žydėjimа, po žydėjimo ir nuėmus derlių. Insekticidas akaricidas Envidoras 240 g/l k. s. 0,3 – 0,6 l/ha juodųjų serbentų apsaugai nuo paprastųjų voratinklinių erkių (Tetranychus urticae Koch.) yra efektyvus purškiant 2 –3 kartus per vegetacijа: prieš ir po žydėjimo bei nuėmus derlių, taip pat apsaugai nuo serbentinių amarų.

Pagal RAPD žymens DNR sekа sukurtas jai specifinis SCAR žymuo, susijęs su braškių atsparumo fitoftorozei (Phytophthora fragariae) Rpf1genu. Naudojant šį žymenį įvertintas geno Rpf1 buvimas skirtingose braškių veislėse ir sėjinukuose. Pagal šiuos duomenis veislės ir hibridiniai klonai ‘Redgauntlet’, ‘Anapolis’; ‘Tristar’, ‘Dangė’, 005001; 005002 turi Rpf1 genа.

Ištirta COR47 geno raiška braškėse užsigrūdinimo metu in vitro. Didžiausias COR 47

geno transkripto kiekis braškėse susidaro po 30 dienų grūdinimo žemose teigiamose temperatūrose.

Reikšminiai žodžiai: braškės, juodieji serbentai, veislių tyrimas, fiziologija, ligos ir kenkėjai, molekuliniai žymenys.