Influence of climatic conditions of northeastern Poland on growth of ...

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

Influence of climatic conditions of northeastern Poland on growth of bower actinidia Zdzisław Kawecki, Anna Bieniek Department of Horticulture, University of Warmia and Mazury in Olsztyn, ul. Prawocheсskiego 21, 10 – 719 Olsztyn, Poland E-mail: [email protected] Studies of the growth of vegetative and generative shoots of bower actinidia (Actinidia arguta Sieb. et Planch.): ‘Purpurowaja Sadowaja’, ‘Kijewskaja Gibrydnaja’, ‘Kijewskaja Krupnopщodnaja’, ‘Figurnaja’ and ‘Sientiabrskaja’ were carried out in the Experimental Garden of University of Warmia and Mazury in Olsztyn in 2005–2007. The shoot length and diameter as well as the number of leaves on one-year-old generative and vegetative shoots were recorded every two weeks from the beginning of vegetation. As a result of three years of observation, varieties ‘Sientiabrskaja’ and ‘Kijewskaja Gibrydnaja’ gave the longest one-year-old vegetative shoots (103.62 cm and 77.79 cm). The most intensive growth of shoots was observed in 2006 and 2007. The shortest vegetative shoots were in variety ‘Figurnaja’ (31.3 cm). The longest generative shoots were in variety ‘Sientiabrskaja’ (mean for 3 years: 34.23 cm), the shortest shoots were in variety ‘Kijewskaja Gibrydnaja’ (14.44 cm). The highest diameter of generative shoots was in variety ‘Purpurowaja Sadowaja’ (0.51 cm). The lowest increasement was recorded in variety ‘Kijewskaja Gibrydnaja’ (0.42 cm). The largest number of leaves on the vegetative shoots was in variety ‘Sientiabrskaja’, but the smallest number of leaves was on generative shoots of variety ‘Purpurowaja Sadowaja’. The most resistant to spring ground frost (freezing of flowers) was ‘Purpurowaja Sadowaja’ and ‘Kijewskaja Gibrydnaja’. Typical to 2007 were series of days with severe ground frosts in the first and last decade of May, which might have affected a lack of fruit setting on shoots of most of the actinidia varieties. Key words: climate, bower actinidia, north-eastern Poland, plant morphology, varieties.

Introduction. Bower actinidia Actinidia arguta (Siebold et Zucc.) Planch. Ex Miq belongs to the genus Actinidia and the family of Actinidiaceae. This genus includes 30–40 species of climbing plants. Actinidia arguta belongs to the section Leiocarpae that encompasses species adapted for low temperatures in the winter season (Latocha, 2006a). Depending on the variety, it survives frosts ranging from -23 °C to -35 °C (Kawecki et al., 2004). On commencing the vegetative seasons, it is capable of surviving slight frosts to -3 °C. In order to delay its vegetation, its cultivation on a western or south-western exposure is recommended (Kawecki et al., 2007). To bear fruits, bower actinidia plants need 150 days without ground frosts (Latocha, 2006 a). Under the moderate climate conditions of Poland, especially of its more chill regions including the province of Warmia and Mazury, it poses a great challenge to gardeners.

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Currently, these fruit-bearing climbers are relatively uncommon, yet their outstanding taste and health-promoting values are arousing the interest of consumers on the fruit market (Werner, 2002). Fruits of bower actinidia ripen at the end of September and berries are 2–5 cm in length depending on variety, with hairless and smooth skin. They occur of the following colors: green, green with blush and red (Bieniek et al., 2006). As compared to kiwi fruits, they are a richer source of vitamin C; they are also claimed to be tastier. In most cases, plants of bower actinidia are free of diseases and pests and may be cultivated with ecological methods (Latocha, 2006 b). Nevertheless, bower actinidia should not be treated only as a fruit plants as they also serve peculiar decorative functions. The plants are readily planted in allotments and home gardens along walls or other constructions. The objective of the study was to characterize the growth of vegetative and generative shoots as well as to determine the number of leaves, flowers and fruits on those shoots in 5 hybrid varieties of bower actinidia: ‘Figurnaja’, ‘Kijewskaja Gibridnaja’, ‘Kijewskaja Krupnopщodnaja’, ‘Purpurowaja Sadowaja’ and ‘Sientiabrskaja’, under climatic conditions of the city of Olsztyn (north-eastern Poland) in 2005–2007. Object, methods and conditions. Five varieties of bower actinidia (Actinidia arguta): ‘Purpurowaja Sadowaja’, ‘Kijewskaja Krupnopщodnaja’, ‘Kijewskaja Gibrydnaja’, ‘Figurnaja’, ‘Sientiabrskaja’ were planted at a spacing of 1.5 × 2 m in the Educational and Experimental Station of the University of Warmia and Mazury in Olsztyn in autumn of 1996. For each variety, five bushes were planted. Male bushes of varieties form were used as pollinators; they were used in the ratio of 1 : 5. The first yield of fruit was obtained in the fourth year after planting. The plants grew in corn-fodder strong complex IV class soil. It is strong clay sand of pH 6.2–6.8. Weeds were removed manually three times per year during the vegetation period. The plants did not have any diseases or pests; therefore no chemical treatment was applied. Morphology of one-year-old vegetative and generative shoots of the examined varieties of actinidia was determined in 200–2007. Results are mean values of three samples measured simultaneously. Each year, from May 16th till September, 19th the following morphological traits were measured every two weeks: length of vegetative shoots, diameter of vegetative shoots, the number of leaves on a vegetative shoot, length of generative shoots, diameter of generative shoots, the number of leaves as well as flowers and next fruits on a generative shoot. The manuscript provides final experimental results of 19th of September 2005, 2006 and 2007. Atmospheric conditions occurring in the area of Olsztyn in 2005–2007 were described with data of the Meteorological Station in Tomaszkowo (Table 1 and 2). Results of measurements of morphological traits were analyzed statistically by calculating the significance of differences between mean values with Duncan’s test at a significance level of p = 0.05 for a two-factor experiment. The statistical software package “Statistica 6.0” was used for calculations. Results. Analyses of climatic conditions in particular years of morphological measurements of the vegetative and generative shoots of the investigated actinidia

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varieties demonstrated that the highest mean temperature of the vegetative season (from April till September) occurred in 2007 and reached 16.0 °C (Table 1). The lowest mean temperature of the vegetative season, i. e. 13.1 °C, was recorded in 2006. As compared to the multiannual mean of 1961–2000, it was lower by 0.5 °C. In the year 2006, especially low temperatures were reported in winter months: -8.5 °C in January, -3.4 °C in February and -2.5 °C in March. In turn, temperatures of the summer months, July and August of 2006 in particular, appeared to be the highest and reached 20.9 °C and 18.2 °C, respectively. When compared to the multiannual mean, they were higher by 3.7 °C in July and by 2.4 °C in August. Table 1. The mean monthly values of weather factors in 2005–2007 and multiannual mean (data of Meteorological Station in Tomaszkowo) 1 lentelė. Klimato veiksnių vidutinės mėnesio reikšmės 2005–2007 m. ir daugiamečiai vidurkiai (Meteorologinės stoties Tomaškove duomenimis)

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In all experimental years, mean temperatures recorded in April were at a similar level, i. e. 7.4 °C, 7.3 °C and 7.5 °C, and were higher than the multiannual mean, which accounted for 7.0 °C. The highest mean temperature of May (13.8 °C) was recorded in 2007. In that year, the highest mean minimum ground temperature was also recorded. In turn, the growth and development of actinidia and especially its blooming were significantly affected by low ground temperatures, which between the 1st and 5th of May reached -6.0 °C, -7.1 °C, -5.8 °C, -3.0 °C and -1.0 °C, respectively (Table 2). Ground frosts were also recorded in the second decade of May, in which there were 7 days with temperatures below zero. In the last two days of May 2007, ground temperatures accounted for -1.4 °C and -3.5 °C, respectively. Table 2. Spring ground frosts in 2005–2007 (data of Meteorological Station in Tomaszkowo) 2 lentelė. Pavasarinės priežemio šalnos 2005–2007 m. (Meteorologinės stoties Tomaškove duomenimis)

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In the first months of the vegetative season (April, May) the lowest total precipitation accounting for 10.9 mm and 24.7 mm, was recorded in 2005. Total levels of precipitation in May of 2006 and 2007 were similar and reached 25.6 and 24.7 mm, i. e. less by ca. 10 mm than the multiannual mean (35.4 mm). In the discussed experimental years, May was characterized by a higher total level of precipitation: 89.2 mm and 93.5 mm, in respect of the multiannual mean that accounted for 57.6 mm. In the summer months, the driest turned out to be July of 2006 with a total precipitation of 29.3 mm. The subsequent month, August, was more abundant in precipitation (as compared to levels recorded in 2005 and 2006 and to the multiannual mean), which total level reached 165 mm. The record of total precipitation was broken in July of 2007, when the total precipitation level reached 173.7 mm. The year 2005 was characterized by the lowest total precipitation in August (33.1 mm), whereas September of 2005 appeared to be the most humid with a total precipitation of 78.4 mm. In the two subsequent years, the total precipitation of September approximated the multiannual mean (50 mm). The lowest level of precipitation in vegetative season was recorded in 2005, i. e. 297.3 mm. In 2006 and 2007 levels of total precipitation in vegetative season were similar and reached 556.9 mm and 564.5 mm, respectively. They were higher than the multiannual mean, which accounted for 378.3 mm. April of 2005 and 2006 was characterized by a similar number of days with slight ground frosts, i. e. 14 and 15, respectively (Table 2). In April of 2007, ground frosts were reported until the 14th of April, whereas the subsequent days of vegetative season were warmer and no minus temperatures were noted. In the first days of May there was a series of 5 days with severe ground frost and negative ground temperatures were still recorded between the 15th and 31st of May. In the two previous years, May frosts were small and occurred in two and three subsequent days. The statistical analysis demonstrated significant differences in all the examined morphological traits both between varieties and between experimental years (Table 3, 4, 5, 6, 7, 8, 9). Table 3. Mean length (cm) of vegetative shoots of bower actinidia in 2005–2007 3 lentelė. Smailialapės aktinidijos vegetatyvinių ūglių vidutinis ilgis (cm) 2005– 2007 m.

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Table 4. Mean length (cm) of generative shoots of bower actinidia in 2005–2007 4 lentelė. Smailialapės aktinidijos generatyvinių ūglių vidutinis ilgis (cm) 2005– 2007 m.

Table 5. Mean diameter (cm) of vegetative shoots of bower actinidia in 2005–2007 5 lentelė. Smailialapės aktinidijos vegetatyvinių ūglių vidutinis skersmuo (cm) 2005–2007 m.

Table 6. Mean diameter (cm) of generative shoots of bower actinidia in 2005–2007 6 lentelė. Smailialapės aktinidijos generatyvinių ūglių vidutinis skersmuo (cm) 2005–2007 m.

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Table 7. Mean number of leaves on vegetative shoot of bower actinidia in 2005–2007 7 lentelė. Smailialapės aktinidijos vegetatyvinių ūglių vidutinis lapų skaičius (cm) 2005–2007 m.

The longest and the thickest vegetative shoots and generative ones with the highest number of leaves, and the lowest numbers of flowers and fruits on generative shoots were recorded in 2007. Observations carried out in three years of the study demonstrate that the longest vegetative shoots were reported for variety ‘Sientiabrskaja’ (103.62 cm), followed by ‘Kijewskaja Gibrydnaja’ (77.79 cm). In turn, the shortest vegetative shoots were noted in variety ‘Figurnaja’, i. e. 31.3 cm. Values of the mean length of one-year-old vegetative and generative shoots appeared to be the lowest in 2005 and reached 31.13 cm (Table 3) and 103.2 cm (Table 4), respectively. In contrast, the highest value of the mean length of the shoots was noted in 2007, i.e. 109. 86 cm (Table 3) and 29.36 cm (Table 4), respectively. In the experimental years, the variety with the highest values of the mean length of generative shoots appeared to be ‘Sientiabrskaja’. The only exception was 2007 when longer shoots (37.7 cm) were observed in variety ‘Figurnaja’. The statistical analysis of results obtained in that year did not demonstrate any significant differences between varieties, which together with variety ‘Kijewskaja Gibrydnaja’ of 2006, constituted a homogenous group with the lowest values. In contrast to the subsequent years of the study, in 2005 variety ‘Sientiabrskaja’ was characterized by the shortest generative shoots: 8.6 cm (Table 4). In plants of this cultivar the longest generative shoots were recorded in 2006: 61.1 cm. Mean values computed for the 3 experimental years for all varieties indicate that the variety with the shortest generative shoots (14.44 cm) was ‘Kijewskaja Gibrydnaja’. The greatest diameters of vegetative and generative shoots were noted in 2007: 0.77 cm (Table 5) and 0.53 cm (Table 6), respectively, whereas the smallest one in 2006: 0.41 cm (Table 5) and 0.38 cm (Table 6), respectively. The greatest diameter of vegetative shoots (0.69 cm, Table 5) in the 3 experimental years was observed in variety ‘Sientiabrskaja’. The varieties ‘Kijewskaja Gibrydnaja’ and ‘Purpurowaja Sadowaja’ generated vegetative shoots with the same mean diameter, i.e. 0.61 cm. The smallest diameter was recorded for shoots of variety ‘Figurnaja’: 0.44 cm. The greatest diameter of generative shoots during 3 years of the study, i. e. 0.51 cm, was noted in variety ‘Purpurowaja Sadowaja’. Shoot diameters of varieties ‘Figurnaja’, ‘Kijewskaja Krupnopщodnaja’ and ‘Sientiabrskaja’ belonged to the same homogenous group and ranged from 0.45 cm to 0.46 cm. Shoots with the smallest diameter (0.42 cm) were formed by variety ‘Kijewskaja Gibrydnaja’.

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In 2005–2006 the number of leaves on both the vegetative and generative shoots of varieties under study turned out to be the lowest (Table 7 and 8). In 2007, the number of leaves on both types of shoots was significantly higher and reached 30.1 (Table 7) and 15 (Table 8), respectively. Table 8. Mean number of leaves on generative shoots of bower actinidia in 2005–2007 8 lentelė. Smailialapės aktinidijos generatyvinių ūglių vidutinis lapų skaičius (cm) 2005–2007 m.

Table 9. Mean number of fruits on generative shoots of bower actinidia in 2005–2007 9 lentelė. Smailialapės aktinidijos generatyvinių ūglių vidutinis vaisių skaičius (cm) 2005–2007 m.

Determination of the number of leaves on vegetative and generative shoots consisted in calculating their density per 10 cm of the shoots (Table 10). The highest number of leaves, on both vegetative and generative shoots, was reported for variety ‘Purpurowaja Sadowaja’, i. e. 4.8 leaves on vegetative shoots and 6.8 leaves on generative shoots. The smallest leaf density determined on vegetative shoots (2.2) was noted for variety ‘Kijewskaja Gibrydnaja’, whereas that calculated on generative shoots (2.4) was for variety ‘Sientiabrskaja’. In 2007, due to high ground frost, most of analyzed varieties did not bloom. Nevertheless, 3 fruits were set on shoots of varieties ‘Kijewskaja Gibrydnaja’ and ‘Purpurowaja Sadowaja’ (Table 9). In respect of all plants examined, they were the only shoots with fruits. The highest number of flowers and then fruits was set on generative shoots in 2005, i.e. on average 18.07. As compared to the other cultivars, highly significantly

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different appeared to be the variety ‘Purpurowaja Sadowaja’, on the shoots of which there were set 36 fruits. Twenty fruits on the generative shoot were reported for variety ‘Sientiabrskaja’. Other varieties did not differ significantly in terms of the number of fruits, which ranged from 10 in variety ‘Kijewskaja Gibrydnaja’ to 13 in variety ‘Kijewskaja Krupnopщodnaja’. The mean results of the 3 experimental years indicate that generative shoots of variety ‘Purpurowaja Sadowaja’ were characterized by a significantly higher number of fruits, i.e. 14.8, which when expressed per 10 cm of the generative shoots accounted for 8.2 fruits. Varieties ‘Figurnaja’ and ‘Sientiabrskaja’ constituted another homogenous group in terms of the number of fruits per shoot, i.e. 9.7 and 7.7 fruits respectively, which when expressed per 10 cm of the shoot gave 4.5 and 3.9 fruits (Table 10). Table 10. Mean number of leaves and fruits expressed per 10 cm of vegetative and generative shoots of actinidia varieties examined in 2005–2007 10 lentelė. Aktinidijos veislių vidutinis lapų ir vaisių skaičius 10 cm vegetatyvinių ir generatyvinių ūglių ilgyje 2005–2007 m.

Varieties Kijewskaja ‘Gibrydnaja’ and ‘Kijewskaja Krupnopщodnaja’ constituted a homogenous group with the lowest number of fruits on generative shoots: 4.7 and 5 fruits (Table 9), which when expressed per 10 cm of the shoot accounted for 3.3 and 2.3 fruits. Discussion. Investigations into the morphology of vegetative and generative shoots of five hybrid varieties of bower actinidia were conducted under climatic conditions of north-eastern Poland, namely in Olsztyn – the capital of the province of Warmia and Mazury. In contrast to other Polish regions, the area of Olsztyn is poorer in horticultural crops, which is due to frequent spring frosts – recorded on average until the 15th of May, in the extreme until 30th of May and locally in June (Grabowski, Grabowska 1983). One of the most detrimental meteorological phenomena faced, among others, by horticulture are claimed to be frosts. Data of 1971–2000 demonstrated that the length of the frost-free period determined at the altitude of 200 cm in the region of the northeastern Poland ranged from 143 days in Gołdap to 173 days in Mikołajki. In turn, the mean length of the frost-free period determined 5 cm above the ground ranged from 112 days in Suwałki to 145 days in Mikołajki (Dragańska et al., 2004). The most common series of frosty days in the Warmia and Mazury province are a one-day series followed by a two-day series. The number of days with frost is observed to diminish along with their length (Dragańska et al., 2004). On May of 2007, there were series of days with

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frost that were noted both in the first and last days of the month. It contributed to a lack of fruit setting on shoots of the examined varieties of actinidia. The climate of the north-eastern Poland, determined mainly by air masses inflowing from the eastern border of the country, has been observed to change in recent years. One of the reasons of this change is global warming, which has led to an increase in the mean annual temperature and, consequently, to a decrease in the total annual precipitation and soil humidity. The noticeable increase of temperature resulted in the elongation of the meteorological vegetative season by 8 days (from 192 to 200 days) in the region of the north-eastern Poland. Undeniably, it is a positive aspect of the contemporary climatic changes, yet the resultant potential deficiency of soil moisture content at low annual precipitation observed so far seems worrying (Ziernicka, 2004). Analyzing the effect of climatic factors on the growth and development of actinidia, the utmost attention should be paid to data referring to temperatures recorded in the winter and summer months. Severe freezing in the winter or very low temperatures in the summer impair the farming of fruit plants (Pieniążek, 2000) by contributing to their poor fruit bearing. One of the negative traits typical of the course of agroclimatic conditions of north-eastern Poland are late spring frosts. The extreme dates of their occurrence have been recorded even in the first half of June (Atlas klimatyczny, 1990). In Actinidii arguta (Siebold et Zucc.) Planch. Ex Miq, there are two types of shoots, namely: those with a relatively short period of length gain – including shortshoots and some long-shoots, and those with a ceaseless growing period which develop far more strongly and when uncut may reach several meters per season – including long-shoots (Latocha, 2006a). In the present study, measurements were performed on shoots terminating their growth and developing to a weaker extent. According to Chojnowska (1998), annual gains are from 1 m to 3 m in length. As claimed by Plechanowa (1982), different varieties of bower actinidia are characterized by varied growth strength and season of particular phenophases. Processes of growth and development are determined by the whole array of extrinsic factors, including light, temperature, water, gravitational force, touch, edaphic factors and chemical stimuli. Out of those factors, a significant role is attributed to light, which, by acting on photosynthetic and other pigments, affects all processes occurring in plant tissues (Nowakowska, Tretyn, 1996). Conclusions. 1. In Olsztyn (north-eastern Poland) during vegetative seasons of the experimental years 2005–2007 the highest temperatures were recorded in the last year of the study. Typical to that year were series of days with severe ground frosts in the first and last decade of May, which might have affected a lack of fruit setting on shoots of most actinidia varieties. 2. The weakest growth of vegetative and generative shoots was observed in 2005, which was characterized by the lowest precipitation in vegetative season. 3. In 2005–2007, the longest vegetative and generative shoots were observed in variety ‘Sientiabrskaja’, followed by variety ‘Kijewskaja Gibrydnaja’. 4. The highest number of flowers and then fruits was observed on shoots of the examined actinidia varieties in 2005. In terms of the number of fruits, variety

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‘Purpurowaja Sadowaja’ with an average of 8.2 fruits on shoots differed significantly from the other studied varieties. 5. In 2007 a few flowers were set on shoots of varieties ‘Purpurowaja Sadowaja’ and ‘Kijewskaja Gibrydnaja’, hence it may be assumed that they are the most resistant to spring frosts. Acknowledgement. This work was supported by grant 2 PO6R 100 28. Gauta 2008 04 10 Parengta spausdinti 2008 04 28

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

Šiaurės rytų Lenkijos klimato sąlygų įtaka smailialapės aktinidijos augimui Z. Kawecki, A. Bieniek Santrauka Smailialapės aktinidijos (Actinidia arguta Sieb. et Planch.) veislių ‘Purpurowaja Sadowaja’, ‘Kijewskaja Gibrydnaja’, ‘Kijewskaja Krupnopщodnaja’, ‘Figurnaja’ and ‘Sientiabrskaja’ vegetatyvinių ir generatyvinių ūglių augimo tyrimai buvo atlikti 2005–2007 m. Varmijos ir Mazurijos universiteto Olštine eksperimentiniame sode. Ūglių ilgis, skersmuo ir lapų skaičius ant vienų metų generatyvinių ir vegetatyvinių ūglių matuotas kas dvi savaitės nuo vegetacijos pradžios. Olštine (šiaurės rytų Lenkija) aukščiausia temperatūra vegetacijos sezono metu užregistruota paskutiniais metais. Tais metais kelios dienos pirmoje ir paskutinėje gegužės dekadoje buvo su stipriomis šalnomis, kurios paveikė daugelio aktinijos veislių vaisių užmezgimа. Labiausia atsparios pavasario šalnoms buvo veislės ‘Purpurowaja Sadowaja’ ir ‘Kijewskaja Gibrydnaja’. Trejų metų tyrimų duomenimis veislių ‘Sientiabrskaja’ ir ‘Kijewskaja Gibrydnaja’ augalai užaugino ilgiausius vienų metų vegetatyvinius ūglius. Trumpiausi vegetatyviniai ūgliai buvo veislės ‘Figurnaja’ augalų. Ilgiausi generatyviniai ūgliai buvo ‘Sientiabrskaja’ veislės augalų, o trumpiausi – ‘Kijewskaja Gibrydnaja’ veislės augalų. Reikšminiai žodžiai: augalų morfologija, smailialapė aktidija, klimatas, šiaurės rytų Lenkija, veislės.

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