Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.
2014
Volume 17
Issue 2
Topic:
Horticulture
ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
Dyduch J. , Suszyna J. , Sałata A. 2014. BIO-PRODUCTIVITY OF TWO CULTIVARS OF INDETERMINATE TOMATO PLANTS IN THE FIELD EXPRESSED IN THE SIZE AND STRUCTURE OF THE FRUIT YIELD, EJPAU 17(2), #03.
Available Online: http://www.ejpau.media.pl/volume17/issue2/art-03.html

BIO-PRODUCTIVITY OF TWO CULTIVARS OF INDETERMINATE TOMATO PLANTS IN THE FIELD EXPRESSED IN THE SIZE AND STRUCTURE OF THE FRUIT YIELD

Jan Dyduch1, Janusz Suszyna2, Andrzej Sałata1
1 Department of Vegetable Crops and Medicinal Plants, University of Life Sciences in Lublin, Poland
2 State Higher Vocational School in Sandomierz, Poland

 

ABSTRACT

Cultivation of indeterminate tomato in the field is one of the most intensive methods for obtaining fruits on the “fresh market”. Fruit harvest largely affects the inputs (labor) and are not regularly carried out. The frequency of harvest depends on the number and ripeness of fruits, possibilities to make harvest, and market trends.

The aim of the study performed in 2007–2010 was to evaluate the yielding of indeterminate tomato in the field at the stakes in the region of Sandomierz. The study was conducted on moderate alluvial soils in the Vistula river valley. The studied object consisted of tomato 'Faustine F1' and 'Brooklyn F1' cultivars. Potted seedlings were planted after 15 May and the plants were carried out for a single shoot by varying the harvest frequency every 2, 4, and 6 days. Fruits were harvested at the stage of full coloring. Based on the tests, a significant dependence between the frequency of harvest vs. total and marketable yields of tomato fruits, was recorded. Significantly the highest total yield (95.0 t·ha-1) was obtained by harvesting the fruits every 4 days, while the lowest – every 2 days (92.8 t·ha-1). The largest marketable yield was achieved by harvesting the fruits every two and four days, although no significant difference were observed between these combinations. Harvesting the fruits every 2 days, the largest share of marketable in total yield was recorded. Analysis of the results also showed a remarkable correlation between the frequency of harvests and average weight of a single fruit, which was the highest at harvests made every 4 and 6 days; there were no significant differences here, either.

Key words: Lycopersicon esculentum, field cultivation, harvest frequency, marketable yield.

INTRODUCTION

The field cultivation of the indeterminate tomato is one of the most intensive methods of its production and harvested fruits are used for “fresh market”. The fruit harvest, which is a significant part of the cost, it is usually not performed regularly. Dates and frequency of harvest depend on the weather conditions affecting the ripening dynamics, harvesting feasibility, market trends, and the number of ripened fruits [24]. Any deviation from optimum terms is unfavorable [4]. Fruits from the early harvest and intended for a longer transport are harvested more frequently and at different stages of coloring, while well-colored and hard ones – to the local markets [20, 21]. Since the growing cycle is composed of variable number of harvests, the manufacturer is not able to observe the effect of the harvest frequency on yielding and quality characteristics of fruits.

Quality traits, as well as the biological value of tomato fruits are the result of both genetic as well as environmental factors determining and modifying the expression of corresponding genes. It is therefore of great importance in future to undertake the research on new cultivars using genetic combinations [14, 15, 23, 25], a stand selection and growing method [1–3, 16, 19, 22, 26, 28], insolation [8, 9, 11–13], as well as variable weather conditions [9, 31–33].

The need for multiple manual harvest depending on the rate of fruit ripening and over-ripening is the most labor-consuming practices (i.e. cost-consuming) during the cultivation of tomato. Therefore, efforts to possibility of reducing the number of fruit harvest at various species are undertaken [5, 6, 30] at large and high-quality yields [17, 27, 29, 30].

Hence, the aim of the study carried out in 2007–2010 was to evaluate the yielding and yield structure of high-growing tomato cultivated in the field at stakes near Sandomierz, depending on the frequency of harvests. This region is one of the largest in Poland in terms of the area under tomato growing according to this technology, which is a result of favorable soil and climate conditions [7, 18, 31, 32].

MATERIALS AND METHODS

The experiment was carried out in 2007–2010 near Sandomierz on moderate alluvial in Vistula river valley with the humus layer thickness of 30–40 cm and slightly acidic reaction (pH 6.5). Tomato plants were grown at the third year after manure. Levels of mineral components was adjusted – on a base of the soil analysis – to the following values [mg·L-1]: 120 N (NO3+NH4), 80 P, 250 K, 80 Mg, and 1200 Ca. Double nitrogen fertilization was made (2 × 20 kg N·ha-1). The potted seedling was planted into the field between 15 and 17 May at 90 × 45 cm spacing. The study object consisted of ‘Faustine F1’ and ‘Brooklyn F1’ tomato cultivars that have been grown since several seasons in that region due to good quality of fruits; seeds of these varieties can be traded, which is legalized by Ministry of Agriculture. All plants grew for a single shoot, and were topped for 6 staff on 20 August. For both cultivars, the harvest frequency was different (every 2, 4, and 6 days), gathering fruits ever at the stage of full coloring. Fruits have been harvested since mid August till the end of September. Each combination was made in triplicate and experimental unit was composed of a plot of 4.05 m2 area with 10 plants growing. After completing every harvest, total and marketable yields, as well as weight of a single marketable fruit, was determined. The marketable fruits were accepted those having at least 35 mm diameter, round and with no disease symptoms. Achieved results were statistically processes by means of variance analysis applying T-Tukey test for significance level α=0.05.

RESULTS

Due to high air temperatures in July, years 2007–2010 should be considered very favorable for tomato cultivation. More detailed analysis reveals that every year of the experiment was characterized by the individual course of weather conditions and unevenly affected the yielding of tomato, which reflected in diverse harvest dates (Tab. 1). Season 2009, with high average temperature in July (20.2°C) and September (15.1°C) and relatively long no-frost period (177 days), as well as moderate rainfall course, was the most favorable (Suszyna 2005 & 2006)

Table 1. Weather course in 2007–2010
Year
Mean air temperature [°C]
No-frost period
Rainfall sum [mm]
V
VI
VII
VIII
IX
V–IX
Since–till
Days
V
VI
VII
VIII
IX
V–IX
2007
15.9
19.2
19.6
19.1
12.7
17.3
4 V–20 IX
139
32
53
104
58
107
354
2008
13.5
18.2
18.8
18.9
12.7
16.4
1 IV–26 X
208
74
29
99
31
83
316
2009
13.7
16.6
20.2
18.5
15.1
16.8
20 IV–14 X
177
73
89
72
58
45
337
2010
14.0
17.8
21.2
19.5
12.3
17.0
23 IV–7 X
167
168
45
125
106
89
533
According to Institute of Meteorology and Water Management in Sandomierz

Very good thermal indicators in 2010 were deteriorated due to heavy rainfalls in July (125 mm) and August (106 mm), and relatively early autumn frosts. The year 2007, despite the fact that was characterized by the highest temperature during the vegetation season, was the worst because of significant precipitations in July and September, as well as short no-frost period.

Based on the study, a significant effect of the harvest frequency on the total and commercial yields of tomato fruits, was recorded. The largest total yield, regardless of cultivar (95.0 t·ha-1), was obtained by harvesting fruits every four days, while the smallest – every 2 days (92.8 t·ha-1) (Tab. 2). There was no significant difference between harvests made every 4 and 6 days. Total yield of fruits was not significantly different between cultivars. The significant impact of the experimental years on the total yield was found and this relationship was observed for both cultivars. The largest marketable yield was obtained by harvesting fruits every 2 days (83.3 t·ha-1) and every 4 days (82.6 t·ha-1), between which there were no considerable differences (Tab. 3). The marketable yield as well as its share in the total yield decreased along with the decrease in the harvest frequency (Fig. 1).

Table 2. Total yield of tomato fruits depending on the harvest frequency in 2007–2010 [t·ha-1]
Cultivar (B)
Year
Harvest frequency (A) [days]
Mean
2
4
6
Faustine F1
2007
66.1
80.8
80.8
75.9
2008
90.4
92.4
93.8
92.2
2009
130.2
121.6
122.5
124.8
2010
81.5
88.3
82.9
84.2
Mean for Faustine F1
92.1
95.8
95.0
94.3
Brooklyn F1
2007
80.6
66.3
72.3
73.1
2008
92.3
98.5
100.6
97.1
2009
117.4
122.5
114.1
118.0
2010
83.7
89.0
86.0
86.2
Mean for Brooklyn F1
93.5
94.1
93.3
93.6
Mean for harvest frequency
92.8
95.0
94.2
–
Mean for years (C)
2007
73.4
73.6
76.6
74.5
2008
91.4
95.5
97.2
94.7
2009
123.8
122.1
118.3
121.4
2010
82.6
88.7
84.5
85.2
LSD0.05: A – 1.30, B – 0.89, C – 1.66, A × B – 2.27, A × C – 3.72, B × C – 2.80, A × B × C – 5.75


Fig. 1. Share of the marketable in total yield depending on the harvest frequency and cultivar in 2007–2010 [%]

The statistical analysis showed a significant dependence of the size of marketable yield on a cultivar and years of the research (Tab. 3). This relationship was most clearly highlighted in the case of 'Brooklyn F1' cv., which is distinguished by larger fruits. For 'Faustine F1' cv., the largest marketable yield was observed at the harvest frequency of every 4 days, yet this effect was not statistically significant.

Table 3. Marketable yield of tomato fruits depending on the harvest frequency in 2007–2010 [t·ha-1]
Cultivar (B)
Year
Harvest frequency (A) [days]
Mean
2
4
6
Faustine F1
2007
64.8
79.1
79.5
74.5
2008
61.5
61.8
64.0
62.4
2009
128.9
117.9
117.0
121.3
2010
71.0
75.4
68.0
71.5
Mean for Faustine F1
81.6
83.6
82.1
83.3
Brooklyn F1
2007
78.0
63.4
71.1
70.8
2008
70.8
65.8
67.6
68.1
2009
117.2
120.3
110.6
116.0
2010
74.3
77.1
71.6
74.5
Mean for Brooklyn F1
85.1
81.7
80.2
82.3
Mean for harvest frequency
83.3
82.6
81.2
–
Mean for years (C)
2007
71.4
71.3
75.3
72.7
2008
66.2
63.8
65.8
65.3
2009
123.1
119.1
113.8
118.7
2010
72.7
76.3
69.8
72.9
LSD0.05: A – 1.26, B – 0.89, C – 1.66, A × B – 2.19,  A × C – 3.59, B x C – 2.70, A × B × C – 5.56

Like marketable yield, its share in the total yield (Fig. 1) underwent similar tendencies. The largest share of marketable yield characterized plants, the harvest of which was made every 2 days (89.3%) as compared with the harvest made every 4 (86.8%) and 6 days (86.3%).

There was a strong correlation between the share of marketable yield and cultivar, mainly at the harvest frequency of every 2 days (Fig. 1). This relationship was particularly evident for 'Brooklyn F1' cv. In terms of the marketable yield share, 'Faustine F1' cv. reacted less dynamically to the change of harvest frequency.

For both cultivars, the largest differences in the share of marketable yield were observed depending on the harvest season (Fig. 2, 3). The smallest share of marketable yield occurred in 2008, in which relatively low temperatures in July contributed to the deterioration of phyto-sanitary status and fruit deformations. 'Brooklyn F1' cv. was more tolerant to different climatic conditions (temperature, precipitation) during the research years in relation to 'Faustine F1' cv.
Fig. 2. Share of the marketable in total yield depending on the harvest frequency and year of experiment for ‘Faustine F1’ cv. in 2007–2010 [%]

Fig. 3. Share of the marketable in total yield depending on the harvest frequency and year of experiment for ‘Brooklyn F1’ cv. in 2007–2010 [%]

The largest weight of a single fruit was achieved when the harvest was made every four and six days, between which no significant differences were observed (Tab. 3). Substantially lower weight of fruits was found when harvests were made every two days (128 g). Moreover, a significant effect of a cultivar and years of the research on the weight of a single fruit was evidenced.

DISCUSSION

The harvest date in the cultivation of tomatoes is usually dependent on the number of ripe fruits and their technological features [24], and the deviation from the optimal date makes the yield effects worse [20, 21]. The results of the experiments confirm the above relationship and the highest total yield was obtained by harvesting fruits every 4 days. Reducing the harvest frequency to 6 days resulted in a decrease in the total yield, but there was no statistically significant difference between harvests every 4 and 6 days. It can be concluded that the presence of ripe fruits on the plant longer than 4 days limits the availability of nutrients for growing fruits resulting in worsened quality and proportion of marketable fruits [33]. The share of marketable fruits also depended on the cultivar, which confirms the opinion that the quality of fruits depends on the cultivar and the time of harvest [17]. However, harvest made more frequently than every four days contributes to raising fruits that have not reached their maximum weight, which significantly influenced on the reduction of the total yield, yet considerably increased the share of marketable fruits in the total yield.

Table 4. Weight of the marketable fruit depending on the harvest frequency [g]
Cultivar (B)
Year
Harvest frequency (A) [days]
Mean
2
4
6
Faustine F1
2007
91
114
140
115
2008
113
112
111
112
2009
140
140
150
143
2010
133
139
122
131
Mean for Faustine F1
119
126
131
125
Brooklyn F1
2007
108
113
115
112
2008
142
148
145
145
2009
160
160
150
157
2010
135
154
144
144
Mean for Brooklyn F1
136
141
139
140
Mean for harvest frequency
128
135
135
132
Mean for years (C)
2007
100
114
128
114
2008
128
130
128
129
2009
150
150
150
150
2010
134
147
133
138
LSD0.05: A – 5.45, B – 3.70, C – 6.93, A × B -9.47, A × C – 15.52 , B × C – 14.69, A × B × C – 24.00

There was a significant correlation of yielding on the weather conditions during the research comparable to the results of other authors [32]. The weakest results for the observed characteristics were recorded in 2007 with the lowest average temperature for the vegetation season (15.7°C), the shortest no-frost period (139 days), and relatively low temperature in July (19.6°C). This is consistent with the parameters of climatic factors determining the period favorable for growing tomatoes [10, 23, 31].

CONCLUSION

  1. Bio-productivity of tomato measured with the fruit yield was significantly dependent on studied factors: cultivar, harvest frequency, and weather parameters in particular years of experiment.
  2. Remarkably higher yield was achieved for ‘Faustine F1’ cv. growing.
  3. Significantly the largest marketable yield was harvested, when it was made every 2 and 4 days as compared to 6 days. The share of the marketable in total yield decreased along with the decrease of the harvest frequency.
  4. The highest weight of a single fruit was produced by harvesting fruits every 4 and 6 days, and the differences were not statistically significant. 
  5. There was a clear dependence between the marketable yield share and the fruit size vs. cultivar and years of study.
  6. Bio-productivity was the most modified due to variable set of weather conditions (temperature, rainfalls) during the experimental years – from 118.7 t·ha-1 in the most favorable to 65.3 t·ha-1 in the least favorable year (difference by 81.7%)

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Accepted for print: 10.04.2014

Jan Dyduch
Department of Vegetable Crops and Medicinal Plants,
University of Life Sciences in Lublin, Poland
58 Leszczyński Street, 20-068 Lublin, Poland
email: jan.dyduch@up.lublin.pl

Janusz Suszyna
State Higher Vocational School in Sandomierz, Poland
13 Schinzl Street, 27-600 Sandomierz, Poland
phone/fax: (+48) 15 644 60 06
email: janusz_suszyna@poczta.onet.pl

Andrzej Sałata
Department of Vegetable Crops and Medicinal Plants,
University of Life Sciences in Lublin, Poland
58 Leszczyński Street, 20-068 Lublin, Poland

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