Abstracts
This study was carried out to obtain estimates of heterosis in crosses between seven eggplant cultivars (Embu = E; Santa Genebra = SG; Viserba = V; Aubergine de Barbentane = AB; Florida Market 10 = FM; Black Beauty = BB, and Melitino = M) and two breeding lines (B-14-07 = B1 and B-31-06 = B2). The F1 hybrids used were: E x FM; E x BB; E x M; E x B1; E x B2; SG x FM; SG x BB; SG x M; SG x B1; SG x B2; V x FM; V x B1; V x B2; AB x FM; AB x M; AB x B1; AB x B2 and M x FM. Cultivars, lines and hybrids were evaluated at the ESAL experimental field in Lavras, MG, from February to October 1992. A randomized complete block design with three replications was used. Significant heterosis relative to the parental means was detected for all traits studied. Their values ranged from +41.23% to +113.31% for total fruit yield, from -11.45% to +26.17% for average fruit weight, and from +27.98% to +141.81% for early production. Heterosis relative to the superior parent ranged from +13.89% to +92.51% for total fruit yield. Hybrid pairs: SG x FM and AB x B1, V x FM and AB x FM, E x M and AB x B1 were the most heterotic relative to the parental mean for total fruit production, mean fruit weight and early production, respectively. The hybrids displaying highest heterosis relative to the superior parent for total yield were AB x B1 and SG x FM.
Este trabalho visou obter estimativas da heterose em cruzamentos entre sete cultivares de berinjela (Embu = E, Santa Genebra = SG, Viserba = V, Aubergine de Barbentane = AB, Florida Market 10 = FM, Black Beauty = BB e Melitino = M) e duas linhagens (B-14-07 = B1 e B-31-06 = B2). Os híbridos F1 utilizados foram: E x FM; E x BB; E x M; E x B1; E x B2; SG x FM; SG x BB; SG x M; SG x B1; SG x B2; V x FM; V x B1; V x B2; AB x FM; AB x M; AB x B1; AB x B2 e M x FM. O trabalho foi conduzido no campus da ESAL em Lavras-MG, de fevereiro a outubro de 1992. O delineamento empregado foi o de blocos casualizados completos com três repetições. Em relação às médias dos pais, houve heterose significativa para os caracteres estudados, variando de +41,23% a +113,31% para produção total de frutos; de -11,45% a +26,17% para peso médio de fruto; e de +27,98% a +141,81% para produção precoce. A heterose em relação ao pai mais produtivo variou entre +13,89% e +92,51% para produção total de frutos. Destacaram-se entre os mais heteróticos, relativamente às médias dos pais, os híbridos SG x FM e AB x B1, para produção total de frutos; V x FM e AB x FM, para peso médio de frutos; E x M e AB x B1, para produção precoce. Em relação ao pai superior, os híbridos com maior heterose para produção total foram AB x B1 e SG x FM.
Expression of heterosis for productive traits in F1 eggplant (Solanum melongena L.) hybrids* * Part of the thesis presented by J.A.S. to ESAL in partial fulfillment of the requirements for the Masters degree.
João Alencar de Sousa 1 and Wilson Roberto Maluf 2
1 EMBRAPA/CPAF-Acre, Caixa Postal 392, 69908-970 Rio Branco, AC, Brasil. Send correspondence to J.A.S.
2 Departamento de Agricultura, Lavras, MG, Brasil.
ABSTRACT
This study was carried out to obtain estimates of heterosis in crosses between seven eggplant cultivars (Embu = E; Santa Genebra = SG; Viserba = V; Aubergine de Barbentane = AB; Florida Market 10 = FM; Black Beauty = BB, and Melitino = M) and two breeding lines (B-14-07 = B1 and B-31-06 = B2). The F1 hybrids used were: E x FM; E x BB; E x M; E x B1; E x B2; SG x FM; SG x BB; SG x M; SG x B1; SG x B2; V x FM; V x B1; V x B2; AB x FM; AB x M; AB x B1; AB x B2 and M x FM. Cultivars, lines and hybrids were evaluated at the ESAL experimental field in Lavras, MG, from February to October 1992. A randomized complete block design with three replications was used. Significant heterosis relative to the parental means was detected for all traits studied. Their values ranged from +41.23% to +113.31% for total fruit yield, from -11.45% to +26.17% for average fruit weight, and from +27.98% to +141.81% for early production. Heterosis relative to the superior parent ranged from +13.89% to +92.51% for total fruit yield. Hybrid pairs: SG x FM and AB x B1, V x FM and AB x FM, E x M and AB x B1 were the most heterotic relative to the parental mean for total fruit production, mean fruit weight and early production, respectively. The hybrids displaying highest heterosis relative to the superior parent for total yield were AB x B1 and SG x FM.
INTRODUCTION
The eggplant (Solanum melongena L.) is a solanaceae native to the tropical regions of the Far East. The high degree of heterosis in eggplants has been reported in several studies, in the Brazilian and world-wide literature (Monteiro, 1975; Noda, 1980; Dixit et al., 1982; Singh and Kalda, 1989; Chadha et al., 1990; Sousa, 1993). Most authors recommend the commercial use of eggplant hybrids because of heterosis for fruit yield traits (Monteiro, 1975).
MATERIAL AND METHODS
Seven open pollinated cultivars (Embu = E, Santa Genebra = SG, Viserba = V, Aubergine de Barbentane = AB, Florida Market 10 = FM, Black Beauty = BB and Melitino = M), two breeding lines (B-14-07 = B1 and B-31-06 = B2), 18 experimental hybrids obtained from the cultivars (E x FM; E x BB; E x M; E x B1; E x B2; SG x FM; SG x BB; SG x M; SG x B1, SG x B2; V x FM; V x B1; V x B2; AB x FM; AB x M; AB x B1; AB x B2 and M x FM) and two commercial hybrids (F-100 and F-1000) were used as experimental materials (Table I).
Table I - Description of the eggplant parentals.
Among the open pollinated cultivars and lines, only those which could be used for seed production, that is, those that did not produce excessively large fruit when mature and/or were good seed producers, were used as the female parent. Seeds from three of the 20 experimental hybrids obtained did not germinate.
The seven cultivars, two lines, 18 F1 hybrids and two commercial hybrids were tested in a randomized complete block design with three replications at the experimental field of the ESAL campus, Lavras, MG, from February to October 1992. Each experimental plot consisted of 10 plants and was spaced at 1.20 x 0.50 m. Growing conditions were maintained similar to those normally used for a commercial eggplant crop. Fourteen harvests were carried out, at seven day intervals, during a three and a half month period.
The assessed traits were:
a. Total yield, expressed in kg/ha;
b. Early yield (1st to 4th harvest), expressed in kg/ha;
c. First class fruit production, expressed in kg/ha;
d. Average weight per fruit, expressed in g/fruit;
e. Average weight of early fruit, expressed in g/fruit.
The fruits classified as first class corresponded to the official commercial classification, classes Extra AA and Extra A. Heterosis relative to the parental mean (Ht = 100) and relative to the superior parent (Hb = 100), named heterobeltiosis, were calculated for the experimental hybrids. In the analyses of variance (ANOVA) the F test was used at the 5% or 1% levels of probability. The trait means were compared by the Tukey test at the 5% level of probability.
RESULTS AND DISCUSSION
The treatment square means, evaluated by the F test, were significant at the 1% probability level for all the assessed traits. All hybrids showed positive heterosis and heterobeltiosis for total yield (Table II). The hybrids displaying high heterosis also had high heterobeltiosis (Table II). Pal and Singh (1946), Odland and Noll (1948), Ikuta (1961) and Monteiro (1975) also found significant heterosis results for this trait. The heterosis magnitude indicates that the use of F1 hybrid plants improves this characteristic. The values obtained for the yield characteristics in the hybrids depended on the parents involved in the crosses, but all the yield characteristics had some type of genetic gain in the hybrids, compared to the parents.
Table II - Total yield (kg/ha), early yield (kg/ha) and first class fruit yield means, heterosis (Ht) and heterobeltiosis (Hb) in eggplants.
Means followed by the same letters did not differ significantly by the Tukey test (Probability = 5%).
E = Embu; SG = Santa Genebra; V = Viserba; AB = Aubergine de Barbentane; FM = Florida Market 10; BB = Black Beauty; M = Melitino; B1 = B-14-07; B2 = B-31-06.
The heterosis and heterobeltiosis for hybrid early yield were also positive (Table II). Among the hybrids, Embu x Melitino, Embu x B-14-07 and Aubergine de Barbentane x B-14-07 were superior. Cultivars Embu and B-14-07 were parentals in those hybrids. The magnitude of the heterosis depended on the genotypes used. The use of F1 hybrids in eggplants provided a quick and practical way of obtaining greater early yields.
Under Brazilian conditions, early yield is not a limiting trait. However, it may be useful in the Southern region when planting is carried out soon after winter. In the temperate regions, the best prices are normally paid at the beginning of the production season, which makes early cultivars more valuable.
For first class fruit yield, heterosis values were all positive and displayed a wide range, of over 300% (Table II). On the other hand, the Santa Genebra x Melitino hybrid displayed a negative heterobeltiosis value. All the other hybrids showed positive values. The large magnitudes for this trait showed, in general, the great superiority of the F1 hybrids, compared to the open pollinated cultivars, for obtaining good quality fruit. Monteiro (1975) and Noda (1980) also reached this conclusion.
First class fruit yield is a production characteristic which allows phenotypic selection of superior genotypes, in a screening process. However, since it does not take into account the yield of slightly inferior but still commercially viable fruits, this criterium cannot be used as the only selection method.
Fruit characteristics are very important in eggplant breeding, as quality in vegetables is as much or more important than quantity (Paterniani, 1974). The assessment criteria for quality values are more efficient than those which merely quantify production (Noda, 1980). The commercial valorization of a crop, in terms of product quality, is dependent on its capacity to concentrate the greatest number of fruit within the market standards.
Positive heterosis for weight of early fruit was detected for the majority of hybrids, with highest positive scores for hybrids Embu x Melitino, Embu x Florida Market 10 and Embu x Black Beauty. On the other hand, the heterobeltiosis values were mostly negative, though the hybrid Embu x Melitino was positive and outstanding (Table III). Following the same tendency of the early assessment, the mean fruit weight had positive heterosis for the majority of the hybrids. Hybrids Viserba x Florida Market 10, Albergine de Barbentane x Florida Market 10 and Santa Genebra x Florida Market 10 were the most heterotic. Heterobeltiosis values were mostly negative. The highest positive values were displayed by the hybrids Embu x B-14-07 and Embu x Melitino (Table III). The mean fruit weight, independent of the heterosis and heterobeltiosis values found, showed small difference from the established standard in the market (commercial F-100 hybrid).
Table III - Average fruit weight (g), average early fruit weight (g), heterosis (Ht) and heterobeltiosis (Hb) in eggplants.
Means followed by the same letters did not differ significantly by the Tukey test (Probability = 5%).
For abbreviations see Table II.
When the yield characteristics are used as assessment criteria, it is desirable that the heterosis and heterobeltiosis levels, shown in the hybrid combinations, be as high as possible. Mean fruit weight and mean weight of early fruit are exceptions since very high heterosis and/or heterobeltiosis values may lead to fruit much heavier than those established by the market.
In view of the high heterosis and or heterobeltiosis values shown for the different characteristics, the importance of the non-additive genetic effects in their expression can be inferred. Thus, it is presumed that the establishment of a population with a wide genetic base, using recurrent selection methods for increasing combining ability along with reciprocal recurrent selection, will lead to future new lines which result in hybrids superior to those studied.
ACKNOWLEDGMENTS
We are grateful to CAPES and CNPq for the study grants given to the first and second authors, respectively, and to PIONEER Seeds, Ltda., for the financial support provided for the experiments.
RESUMO
Este trabalho visou obter estimativas da heterose em cruzamentos entre sete cultivares de berinjela (Embu = E, Santa Genebra = SG, Viserba = V, Aubergine de Barbentane = AB, Florida Market 10 = FM, Black Beauty = BB e Melitino = M) e duas linhagens (B-14-07 = B1 e B-31-06 = B2). Os híbridos F1 utilizados foram: E x FM; E x BB; E x M; E x B1; E x B2; SG x FM; SG x BB; SG x M; SG x B1; SG x B2; V x FM; V x B1; V x B2; AB x FM; AB x M; AB x B1; AB x B2 e M x FM. O trabalho foi conduzido no campus da ESAL em Lavras-MG, de fevereiro a outubro de 1992. O delineamento empregado foi o de blocos casualizados completos com três repetições. Em relação às médias dos pais, houve heterose significativa para os caracteres estudados, variando de +41,23% a +113,31% para produção total de frutos; de -11,45% a +26,17% para peso médio de fruto; e de +27,98% a +141,81% para produção precoce. A heterose em relação ao pai mais produtivo variou entre +13,89% e +92,51% para produção total de frutos. Destacaram-se entre os mais heteróticos, relativamente às médias dos pais, os híbridos SG x FM e AB x B1, para produção total de frutos; V x FM e AB x FM, para peso médio de frutos; E x M e AB x B1, para produção precoce. Em relação ao pai superior, os híbridos com maior heterose para produção total foram AB x B1 e SG x FM.
REFERENCES
Chadha, M.L., Joshi, A.K. and Ghai, T.R. (1990). Heterosis breeding in brinjal. Indian J. Agric. Sci. 47: 417-423.
Dixit, J., Bhutani, R.D. and Dudi, B.S. (1982). Heterosis and combining ability in eggplant. Indian J. Agric. Sci. 52: 444-447.
Ikuta, H. (1961). Vigor de híbrido na geração F1 em berinjela (Solanum melongena L.). Doctoral thesis, ESALQ/USP, Piracicaba, SP.
Monteiro, M.S.R. (1975). Comportamento heterótico e estabilidade fenotípica em híbridos de berinjela (Solanum melongena L.). Masters thesis, ESALQ/USP, Piracicaba, SP.
Noda, H. (1980). Critérios de avaliação de progênies de irmãos germanos interpopulacionais em berinjela (Solanum melongena L.). Masters thesis, ESALQ/USP, Piracicaba, SP.
Odland, M.L. and Noll, C.J. (1948). Hybrid vigour and combining ability in eggplants. Proc. Am. Soc. Hortic. Sci. 51: 417-422.
Pal, B.P. and Singh, H.B. (1946). Studies in hybrid vigour. II - Notes on the brinjal and bitter gourd. Indian J. Genet. & Plant. Breed. 6: 19-33.
Paterniani, E. (1974). Estudos Recentes sobre Heterose. Fundação Cargill, São Paulo, SP, pp. 36.
Singh, H. and Kalda, T.S. (1989). Heterosis and genetic architecture of leaf and yield characters in eggplant. Indian J. Hortic. 46: 53-58.
Sousa, J.A. (1993). Avaliação da heterose em híbridos de berinjela (Solanum melongena L.). Masters thesis, ESAL, Lavras, MG.
(Received November 16, 1994)
- Chadha, M.L., Joshi, A.K. and Ghai, T.R. (1990). Heterosis breeding in brinjal. Indian J. Agric. Sci. 47: 417-423.
- Dixit, J., Bhutani, R.D. and Dudi, B.S. (1982). Heterosis and combining ability in eggplant. Indian J. Agric. Sci. 52: 444-447.
- Ikuta, H. (1961). Vigor de híbrido na geraçăo F1 em berinjela (Solanum melongena L.). Doctoral thesis, ESALQ/USP, Piracicaba, SP.
- Monteiro, M.S.R. (1975). Comportamento heterótico e estabilidade fenotípica em híbridos de berinjela (Solanum melongena L.). Masters thesis, ESALQ/USP, Piracicaba, SP.
- Noda, H. (1980). Critérios de avaliaçăo de progęnies de irmăos germanos interpopulacionais em berinjela (Solanum melongena L.). Masters thesis, ESALQ/USP, Piracicaba, SP.
- Odland, M.L. and Noll, C.J. (1948). Hybrid vigour and combining ability in eggplants. Proc. Am. Soc. Hortic. Sci. 51: 417-422.
- Paterniani, E. (1974). Estudos Recentes sobre Heterose Fundaçăo Cargill, Săo Paulo, SP, pp. 36.
- Singh, H. and Kalda, T.S. (1989). Heterosis and genetic architecture of leaf and yield characters in eggplant. Indian J. Hortic. 46: 53-58.
- Sousa, J.A. (1993). Avaliaçăo da heterose em híbridos de berinjela (Solanum melongena L.). Masters thesis, ESAL, Lavras, MG.
Publication Dates
-
Publication in this collection
06 Jan 1999 -
Date of issue
Mar 1998
History
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Received
16 Nov 1994
