SCIENTIA HORTlCULTURR ELSEVIER
ScientiaHorticulturae61 (1995) 285-290
Short Communication
Response of three sweet pepper cultivars to Biozyme under unheated plastic house conditions Sayed Fathey El-Sayed Vegetable Crops Department, Faculty ofAgriculture, Cairo University,Cairo, Egypt
Accepted2 1 September1994
Abstract
Two experiments were carried out in an unheated plastic house to study the response of three pepper (Cupsicum annuum L. ) cultivars, i.e. ‘Blemont’, ‘Domino’ and ‘Atol’, to Biozyme, applied at 0, 1 and 2 ml 1-i at flower initiation followed by two sprays at an interval of 21 days. Biozyme is an extract of vegetable origin that contains, in ppm, 32.2 indoleacetic acid (WA), 32.2 GAS, 83.2 zeatin, 4900 Fe, 1200 Mn, 3000 B, 3700 Zn, 1400 Mg and 4400 S. Results indicated that ‘Blemont’ was the best cultivar regarding the number of early and total fruits, weight of total yield, while cv. ‘Atol’ gave the highest values of early yield, average fruit weight, and ascorbic acid in fruits. Two millilitres of Biozyme gave the best results with regard to height and weight of plants, number and weight of total fruits, and ascorbic acid in fruits. However, the highest average of fruit weight was produced by 1 ml Biozyme. Generally, Biozyme significantly increased early yield compared with untreated plants with no significant differences between the two concentrations used. Keyworuk:Biozyme;Cultivars;Pepper;Unheated plastichouse
1.Intruductlon In Egypt, sweet pepper (Capsicum annuum L. ) is grown in plastic houses for early production during the period from December to April for export and consumption. These plastic houses are simple and do not have environmental control. Fluctuations in temperature and humidity are therefore large and frequently extend beyond the suitable range for plant growth and fruit set and development. The average minimum and maximum temperatures of 199 1- 1992 and 1992- 1993 measured in unheated plastic house were 9.8”C and 28.2”C in December, 7.7”C and 24.7”C in January, 9.1 “C and 28.1 “C in March, respectively. It was previ03044238/95/$09.50
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ously proved that the optimal fruit set in pepper was obtained at 12- 16’ C (Cochran, 1936). Fruit development at low temperatures may be influenced by pollen infertility (Polowick and Sawhney, 1985 ). More recently, Olarewaju ( 1989) reported that almost all pepper fruits formed at 5 and 10°C were parthenocarpic, and were generally small and malformed. After Gustafson ( 1936) discovered that auxins were effective in fruit set of tomato, pepper, eggplant and okra, numerous compounds were tested on fruit set of pepper such as GA3 (Patil et al., 1985; Zayed et al., 1985; Siviero, 1989), GA3 +morphactin (Zayed et al., 1985) and microelements (Kiss, 1979; El-Abdeen and Metwally, 1982). The objective of the present work was to study effect of a biostimulant complex containing indoleacetic acid (WA), GA3, zeatin, Fe, Mn, B, Zn, Mg and S on the vegetative growth and yield of three sweet pepper cultivars grown under unheated plastic house conditions.
2. Materials and methods Two experiments were carried out during the winter seasons of 199 1 and 1992 in the plastic houses of the Experimental Station, Faculty of Agriculture, Cairo University, Egypt. Seeds of three sweet pepper hybrids, ‘Blemont’, ‘Domino’ (from Asgrow Co., USA) and ‘Atol’ (from EZ Co., Holland) were sown in 84 Speedling trays on 16 and 19 September 199 1 and 1992. The plants were transplanted on 11 and 16 December 199 1 and 1992, on double rows 140 cm wide with a spacing of 50 cm between plants. This achieved a plant density of 2.5 plants mm2. The experiments were arranged in a split-plot design in three replicates. The three pepper cultivars represented the main plots, while the concentrations of Biozyme represented the subplots. Biozyme, which was obtained from Bioenzymas (S.A. de C.V. Co., Mexico), is an extract of vegetable origin that contains (in ppm) 32.2 IAA, 32.2 GAS, 83.2 zeatin, 4900 Fe, 1200 Mn, 3000 B, 3700 Zn, 1400 Mg and 4400 S. Biozyme was applied as a foliar spray on plants three times during the flowering stages at 2 1 day intervals starting at flower initiation (65 days after transplanting). Biozyme was used at concentrations of 0, 1 and 2 ml 1-l distilled water. Triton B at 0.05% was used as a wetting agent for all treatments and control. Irrigation and nutrient supply was provided via a drip system. Fertigation, training and pest control were followed as commonly practiced for pepper production under unheated plastic house conditions. Data were recorded on vegetative growth (height and fresh weight of plants) at the end of growing season, early yield m-’ (number and weight of fruits in the first three pickings), total yield me2 as number and weight of fruits throughout the harvesting season (eight pickings), and chemical content of fruit at the fourth picking (total soluble solids percentage using hand refractometer and ascorbic acid using the method described by the Association of Official Agricultural
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Chemists ( 1965 ). All data were statistically analyzed using combined analysis as described by Snedecor and Cochran ( 1967).
3. Results and discussions 3. I. Vegetative growth
Data presented in Table 1 show that plants of cv. ‘Atol’ were significantly taller than those of ‘Blemont’ and ‘Domino’. A significant increase in plant height was achieved using Biozyme at both concentrations. A significant increase was also detected in plant weight, but only by the higher concentration of Biozyme. These results were expected since Biozyme is a complex of three growth stimulants (MA, GA3 and zeatin) which promote stem elongation by increasing rate of cell division and elongation (Weaver, 1972), and it contains microelements which have Table 1 Effect of Biozyme concentrations on some morphological characters and early yield of three pepper cultivars under unheated plastic house conditions (combined data of two seasons) Cultivar
Biozyme cont. (ml 1-r)
Morphological characters
Early yield
Plant height (cm)
Fresh weight (g)
Fruit number (m-*)
Fruit weight (IZ)
Yield (kg rnm2)
‘Blemont’
0 1 2 Mean
79.90 92.50 100.00 90.80
674.70 675.00 795.90 715.20
25.60 34.00 41.90 33.80
107.00 122.00 102.00 110.30
2.737 4.149 4.27 3.719
‘Domino’
0 1 2 Mean
79.90 90.00 105.00 91.70
662.00 675.00 775.00 704.20
19.60 27.90 23.90 23.80
123.00 94.00 126.00 114.30
2.404 2.615 3.006 2.675
‘At01
0 1 2 Mean
111.60 115.00 127.50 118.10
712.50 770.90 775.00 752.80
24.20 31.40 29.40 28.40
142.00 144.00 136.00 140.70
3.439 4.534 4.00 3.99
Mean
0 1 2
90.50 99.20 110.80
683.20 706.70 782.00
23.20 31.10 31.70
124.00 120.10 121.30
2.86 3.766 3.759
LSD at 0.05% for cultivars (Cvs) Biozyme cont. Cvs x cont.
7.2 5.5 14.1
NS 80 NS
2.2 1.4 2.2
3 1.6 2.6
0.317 0.146 0.243
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been identified as enzyme activators and are of importance for chlorophyll synthesis (Bergmann, 1983). The interaction between pepper cultivars and Biozyme was significant for plant height only. Biozyme at 2 ml 1-l led to a significant increase in plant height of each cultivar compared with the untreated plants. 3.2. Early yield There were significant differences in average fruit weight and number and weight of fruits m-’ among pepper cultivars (Table 1). ‘Blemont’ produced the highest number of fruits that were the smallest in size. However, ‘Atol’ produced a lower number of fruits that were of the largest size. These two cultivars produced significantly higher early yield than ‘Domino’. These results indicate that there was a negative relationship between number of fruits produced by plant and average fruit weight. An increase in number and weight of fruits m-’ was recorded owing to Biozyme application, though no significant differences were observed between both concentrations. However, treating plants with Biozyme caused a significant decrease in average fruit weight. The interaction of Biozyme x cultivars was significant. Pepper cultivars responded differently to Biozyme concentrations. The higher concentration of Biozyme of 2 ml l- ’ gave higher yield except in cv. ‘Atol’. It was observed that ‘Blemont’, whose yield depends on production of high number of fruits, responded more to Biozyme application. However, the two concentrations of Biozyme significantly increased the number of fruits produced by each of the three cultivars. Since the minimal temperature during fruit setting of early fruits was 9°C in the present work, this indicates that under low temperatures, Biozyme improved fruit set of pepper. Previous studies (Polowick and Sawhney, 1985) revealed that pepper pollen become infertile at low temperature. Meanwhile, GA3 application promotes anther development and increases the amount of viable pollen (Mapelli et al., 1979) or reduces flower abortion when it is applied in combination with benzyladenine (Kinet, 1977). It was also found that Biozyme at 1 ml l- ’ increased average fruit weight of ‘Blemont’ which produces large number of small fruits, while 2 ml increased the number of fruits in ‘Domino’ which produces low number of fruits. 3.3. Total yield Data presented in Table 2 show that ‘Blemont’ gave the highest total yield mm2. ‘Domino’ followed ‘Blemont’ in the number of fruits ms2, whereas ‘Atol’ significantly exceeded the other two cultivars in the average fruit weight. Biozyme led, generally, to a significant increase in the number of fruits, average fruit weight and total yield. However, the highest total yield and number of fruits m-2 was produced by the higher concentration of Biozyme. The relatively high minimum temperatures ( 12- 16 ‘C ) which prevailed during fruit set in most of the harvesting season are considered optimal temperatures for fruit set (Cochran,
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Table 2 Effect of Biozyme concentrations on total yield and chemical contents of fruit of three pepper cultivat-s under unheated plastic house conditions (combined data of two seasons) Cultivar
Biozyme cont. (ml 1-r)
Total yield Fruit number (m-*)
Fruit weight (g)
Yield (kg m-2)
TSS (%)
Ascorbic acid (mg per 100 9)
‘Blemont’
0 1 2 Mean
93.30 93.50 101.90 96.20
100.10 111.30 104.80 105.40
9.342 10.409 10.681 10.144
5.40 4.90 4.60 5.00
117.30 184.70 192.30 164.80
‘Domino’
0 1 2 Mean
77.20 87.50 92.90 85.90
100.40 109.50 109.10 106.30
7.751 9.581 10.139 9.157
5.60 5.30 5.10 5.30
188.30 167.50 189.50 181.80
‘Atol
0 1 2 Mean
64.00 71.50 86.20 73.90
121.90 133.30 124.50 126.60
7.802 9.531 10.73 9.355
5.30 5.30 5.00 5.20
144.00 255.50 307.80 235.80
Mean
0 1 2
78.20 84.20 93.70
107.50 118.00 112.80
8.298 9.84 10.517
5.50 5.20 4.90
149.90 202.60 227.80
3.7 4.4 9.9
4.5 3 6.8
0.617 0.432 0.958
0.2 0.2 0.4
7.7 7.6 11.4
LSD at 0.05% for Cultivars (Cvs) Biozyme cont. Cvs x cont.
Chemical contents of fruit
1936). Consequently, Biozyme was not as effective during this period as it was for early yield. However, the lower concentration of Biozyme gave the highest value of average fruit weight which is preferred for growers and consumers in Egypt. As can be expected, fruit weight and number of fruits are negatively related. Both concentrations of Biozyme significantly increased the number and average weight of fruits in ‘Domino’. In ‘Blemont’ and ‘Atol’ Biozyme at 1 ml l- ’ produced the highest fruit weight, whereas 2 ml l- ’ gave the highest fruit numbers in these cultivars. This increase in the number of fruits produced and/or the average fruit weight led to a significant increase in total yield of all the three cultivars. An increase in pepper yield was also previously recorded owing to an increasing number of fruits per plant upon treating with Mg (Kiss, 1979), IAA+NAA (Patil and Ballal, 1980), or NAA (Patil et al., 1985) or owing to increasing average fruit weight after treating with Mn + Fe ( El-Abdeen and Metwally, 1982) or NAA (Patil et al., 1985).
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3.4. Chemical contents offruit
Data presented in Table 2 show that the differences among the three cultivars, the concentrations of Biozyme, and the interaction between them were significant. Cultivars may be classified in descending order according to fruit content of ascorbic acid as follows: ‘Atol’, ‘Domino’ and ‘Blemont’. Raising the concentration of Biozyme from 1 to 2 ml l- ’ led to a significant increase in ascorbic acid content compared with the untreated plants. In spite of this increase in the nutrient value of fruits for the consumer, high yield is more important for the growers. Similarly, Patil et al. ( 1985 ) and Zayed et al. ( 1985 ) observed an increase in ascorbic acid in pepper fruits by using NAA and GA3, respectively. Both Biozyme concentrations decreased the total soluble percentage of the fruits. References Association of Official Agricultural Chemists, 1965.Offrcial Methods of Analysis, 10th edn. AOAC, Washington, DC. Bergmann, W., 1983. Emahrungsstorungen bei Kulturpflanzen, Entstehung und Dignose. VEB Gustav Fischer, Jena, 6 14 pp. Cochran, H.L., 1936. Some factors influencing growth and fruit setting in the pepper (Capsicum fruitescens L.). Cornell Memoir 190. El-Abdeen, A.Z. and Metwally, A.M., 1982. Effect of foliar spraying with Mn, Fe, Zn, Cu on the quality of tomato and pepper. Agric. Res. Rev., 60: 143-l 64. Gustafson, F.G., 1936. Inducement of fruit development by growth promoting chemicals. Proc. Natl. Acad. Sci. US, 22: 628-636. Kinet, J.M., 1977. Effect of defoliation and growth substances on the development of the inflorescence in tomato. Sci. Ho&c., 6: 27:35. Kiss, A.S., 1979. Effect of magnesium fertilization on capsicum and tomato yield. Kertgazdasag, 11: 65-68. (Hortic. Abstr., 51: 5509.) Mapelli, S., Badino, M. and Soressi, G.P., 1979. Effect of GAS on flowering and fruit set in a mutant oftomato. HortScience, 14: 736-737. Olarewaju, J.D., 1989. Effect of night temperature on fruit set and development in sweet pepper (Capsicum annuum L.). Haryana J. Sci., 18: 285-288. (Hortic. Abstr., 60: 7334.) Patil, P.K. and Ballal, A.L., 1980. Effect of seed treatment and foliar spray of various growth regulators on flower drop and yield of green chilli (Cap&urn annuum L.) variety NP-46-A. J. Maharashtra Agric. Univ., 5: 195-197. (Hortic. Abstr. 51: 9419.) Patil, U.B., Sangale, P.B. and Desai, B.B., 1985. Chemical regulation of yield and composition of chilli (Capsicum annuum L.) fruits. Cum Res. Rep., 1: 39-41. (Hot-tic. Abstr., 56: 345.) Polowick, P.L. and Sawhney, V.K., 1985. Temperature effects on male fertility and flower and fruit development in Capsicum annuum L. Sci. Hortic., 25: 117-127. Siviero, P., 1989. The application of biostimulants to dual purpose capsicum. Inf. Agrar., 45: 95-97. (Hortic. Abstr., 60: 8 139. ) Snedecor, G.W. and Cochran, W.G., 1967. Statistical Methods, 6th edn. Iowa State University, Ames, 593 pp. Weaver, R.J., 1972. Plant Growth Substances in Agriculture. Freeman, San Francisco, CA, 494 pp. Zayed, E.A., El-Zawily, AI., Nofal, E.S. and Hassan, M., 1985. Studies on growth, productivity and some physiological aspects of hot pepper (Capsicum annuum L. var. Red Cherry). I. Effect of morphactin, gibberellic acid and their combination. J. Agric. Sci. Mansoura Univ., 10: 193- 190.