Diallel Analysis of Elite Tomato Lines Comprising Leaf Curl Virus Resistance Genes

Abstract

Tomato leaf curl virus is a serious threat to an autumn-winter crop of tomato in North India, causing yield losses up to 90-100%. Therefore, nine resistant and one susceptible line (Punjab Chhuhara) of tomato were crossed in half-diallel fashion to develop 45 F 1 hybrids. Parents and their hybrids were evaluated for yield and quality traits under natural epiphytotic field conditions. There were extensive differences in the performance of parental lines carrying similar and different resistance genes (Ty-X). Of three parental lines carrying Ty-2 gene, CLN 17 performed better than 2123D and 2123C in respect of mean and general combining ability (GCA) for total yield and fruit weight. Likewise, out of three parental lines incorporating two resistance genes (Ty-1 and Ty-2), the line CLN 138B had better mean values and GCA for total yield and fruit weight than CLN 138A and CLN 104. However, the parental line CLN 154 with three different resistance genes (Ty-1, Ty-2, Ty-3) showed the best GCA for total yield, and it was followed by genotype CLN 138B comprising of two resistance genes (Ty-1 and Ty-2). However, the parental lines carrying Ty-2 gene alone produced three useful hybrids expressing 19 to 28% heterosis over top parent for total yield. Four highly significant cross-combinations can be recommended for pedigree selection to develop superior inbred lines. The top parent CLN 154 yielding significantly higher than released varieties along with seven F 1 hybrids manifesting 16 to 31% top parent heterosis for total yield can be recommended after multi-location evaluations. Overall, this study provides useful information on the successful leaf curl virus resistant gene combinations under the north-Indian conditions.

Genetic Associations Analysis in Tomato (Solanum lycopersicum L.) Involving Improved Germplasm Lines for Agronomic and Yield Contributing Traits

“…The magnitude of heterosis depends on the genetic diversity existing between the parents. In a crop like a tomato, where there are evidences for polygenic action determining the yield, and the yield components the choice of parents must be based on refined biometrical techniques (Vijeth et al, 2019).…”

Half diallel of F1 tomato hybrid and its double cross-compatibility

“…ANOVA on the half diallelic showed a significant effect on all characters, indicating that the half diallelic concept was effective. The effectiveness of using the half diallelic mating design was also reported by Pandiarana et al (2015); Kumar and Paliwal (2016); Kaushik and Dhaliwal (2018);and Vijeth et al (2019) on tomatoes, Boyaci et al (2020) and Datta et al (2021) on eggplant, andDianga et al (2020) on rice. Based on these studies, an in-depth analysis of genetic parameters, namely heritability, gene action, and combining ability, can be determined.…”

Estimation of Hybrid Vigor for Flowering and Yield Cherry Tomato Hybrids

“…It was shown that the two hybrids R1×Y53 and R1×F3 gave significant heterozygosity to the average fruit weight on the basis of the best parents, while the hybrid Y53×D4 gave positive hybrid vigor in the direction Desired number of fruits, plant yield and total yield based on the best of the parents. Confirmed [12] in a study conducted at Punjab Agricultural University when they studied ten pure lines of tomato and forty-five individual crosses, the hybrid vigor measured on the basis of the best parents was significant and desirable in hybrids CLN138B × PVB-1, CLN138A × CLN154 and CLN1138B × 2123C, for the average weight of the fruit The plant yield, in general, the hybrids recorded an increase in the percentage of the total yield, the average weight of the fruits and the total acidity of the fruits compared to the pure lines. as proven [13] Through the study to evaluate 30 hybrids produced by complete cross-crossing, most of the hybrids gave high hybrid vigor to most important traits such as yield traits.…”