Combining ability studies for seed quality traits in brinjal (Solanum melongena L.)

Introduction

The botanical name for brinjal is Solanum melongena L. with chromosome number 2n = 24, and it is a member of the Solanaceae family. Brinjal is one of the important vegetable crops globally, with India ranking as the second-largest producer after China. According to FAOSTAT (2022) [4] , brinjal is cultivated worldwide on approximately 1.85 million hectares, producing around 56.62 million tonnes annually, with an average productivity of 30.64 tonnes per hectare. In India, the crop covers nearly 0.74 million hectares, yielding about 12.77 million tonnes, with a productivity of 17.24 tonnes per hectare. In Maharashtra, brinjal is grown on about 0.02 million hectares, contributing an annual production of 0.34 million tonnes and maintaining an average productivity of 17 tonnes per hectare (NHB, First Advance Estimates 2021-22). Based on general combining ability (GCA) and special combining ability (SCA), breeders can select acceptable genotypes as parents during hybridization for improved cross combinations. Appropriate parent selection based on their combining ability is essential for every breeding effort. Considering all these points present study was carried out to study combining ability for seed germination in brinjal.

Materials and Methods

The study was conducted during the Rabi season of 2023-24 at the Seed Unit of Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli, Maharashtra. The experimental material consisted of eight parental genotypes and their 15 F₁ hybrids developed using an L × T mating design. The trial was arranged in a Randomized Block Design with three replications. Observations were recorded on key seed quality parameters, including seed germination percentage, seedling shoot length (cm), seedling root length (cm), and seedling dry weight, based on five randomly selected plants from each parent and hybrid in every replication. The collected data were averaged and subjected to appropriate statistical analysis.

Results and Discussion

The success of hybridization and selection mostly depends on the correct choice of good parents for desirable traits.

According to Gilbert (1958) [5] , parents exhibiting higher mean performance are more likely to contribute to the development of superior genotypes. Similarly, Amarnath and Subramanyam (1992) [1] emphasized that parent selection in breeding programs should consider both mean performance and combining ability. Therefore, in the present study, these two criteria were used as the basis for selecting desirable parental lines. Singh et al. (1983) [11] reported that parents exhibiting superior performance are of greater importance and value in crop improvement and breeding programmes. In the present investigation, line Bandhtiware (BDHE) shown superior performance for the characters root length (cm), vigour index II and dry seedling weight while line Kasral shown good performance for remaining all seed quality characters namely germination (%), shoot length (cm), shoot length/root length, vigour Index II and 100 seed weight. Among the testers Konkan Prabha (KP) shown good performance for germination (%), Swarn Pratibha shown superior performance for shoot length/root length, 100 seed weight, Lanja Local shown good performance for four seed quality characters viz., root length (cm), vigour Index I, vigour Index II and dry seedling weight while tester BB64 was found superior for shoot length (cm). Overall, the parental lines Bandhtiware, Kasral, Konkan Prabha, Swarn Pratibha, Lanja Local, and BB 64 showed favorable performance for most of the evaluated seed quality traits. These genotypes were therefore identified as promising parents and can be effectively utilized in future breeding programmes. (Table 4).

Combining ability is a key parameter widely used in plant breeding to assess the genetic potential of breeding materials. Dhillon (1975) [3] emphasized that combining ability provides valuable guidance in selecting parents based on the expected performance of hybrids and their progenies. General combining ability (GCA) reflects the genetic worth of a parent for a particular trait and is mainly associated with additive gene effects, which are heritable and fixable (Simmonds, 1979) [8] . Furthermore, Singh and Nanda (1976) [10] recommended including at least one parent with high GCA effects as an important criterion in parent selection for breeding programmes. Among the lines significant and positive general combing ability effect was recorded by Bandhtiware (BDHE) for the characters germination (%), root length (cm) and Vigour Index I, Kali Ravai (KR) for all seed quality characters except shoot length/root length and dry seedling weight, Kasral (KL) for shoot length/root length. similar results were recorded by Varshney et al. (1999) [12] , Singh et al.

(2002) [9] and Bendale et al. (2005) [2] in brinjal. Among the testers significant general combing ability effect was recorded by Konkan prabha (KP) for the characters germination (%), root length (cm) and 100 seed weight, Swarna Pratibha (SP) for shoot length/root length, Singhnath (S) for all seed quality characters except root length (cm), Lanja Local (LL) for germination (%), Vigour Index II, 100 seed weight and dry seedling weight while tester BB 64 recorded significant general combing ability effect for all seed quality characters. These results are in accordance with the result of Kannanbabu et al. (2005) [6] in sorghum.

From the above findings, it can be concluded that no single parent possessed favorable genes for all the traits under study. Hence, multiple crosses among these parents would be beneficial for developing superior recombinants combining desirable characteristics. The relationship between per se performance and GCA effects reflects the breeding potential of individual genotypes. In the present investigation, both these parameters were found to be high in the selected parents, indicating their suitability for use in breeding programmes. When considering all the traits, 5 parents Bandhtiware (BDHE), Kasral (KL), BB64, Lanja Local (LL) and Singhnath (S) were adjudged as best parents (table 5). Therefore, multiple crosses involving these five parents would yield good sergeants with all the seed quality traits in brinjal.

References

1. Amarnath S, Subramanyam GS. Combining ability for seedling traits in chewing tobacco (Nicotiana tabacum L.). Ann Agric Res. 1992;13:330-334.
2. Bendale VW, Mane SV, Bhave SG, Madav RR, Desai SB. Combining ability studies on growth and development characters in brinjal (Solanum melongena L.). International J Agric Sci. 2005;1(1):30-33.
3. Dhillon BS. The application of partial-diallel crosses in plant breeding review. Crop Improv. 1975;2:1-7.
4. FAOSTAT. Crops and livestock products -brinjal (eggplant) production statistics. Rome (Italy): Food and Agriculture Organization of the United Nations; 2022.
5. Gilbert NEC. Diallel cross in plant breeding. Heredity. 1958;12:477-498.
6. NHB. First advance estimates. 2021-22.
7. Simmonds NW. Principles of crop improvement. London: Longman Group Ltd; 1979. p.110-116.
8. Singh AK, Rai M, Pan Prasad VSPK, Rai M. Combining ability of quantitative characters in brinjal (Solanum melongena L.). Veg Sci. 2002;29(2):127-130.
9. Singh DP, Nanda JS. Combining ability and heritability in rice. Indian J Genet. 1976;36(1):10-15.
10. Singh VK, Singh HG, Chauhan YS. Combining ability on sesame. Indian J Agric Sci. 1983;53:305-310.
11. Varshney NC, Singha YV, Singh BV. Combining ability studies in brinjal (Solanum melongena L.). Veg Sci. 1999;26:41-44.