Multivariate assessment of newly developed guava (Psidium guajava L.) hybrids for tree and fruit quality traits

Guava (Psidium guajava L.) is an important commercial fruit crop valued for its exceptional nutraceutical value and pharmacological properties. Growing awareness about guava's health benefits is driving demand for higher-quality, nutraceutical-rich cultivars. Varietal development and genetic improvement in guava involve crossing between heterozygous elite parents to generate segregating full-sib populations for future selection. In this study, hybridization between Allahabad Safeda and Arka Kiran, was attempted, and hybrid progenies were raised. A total of 50 hybrid progenies were confirmed as hybrid with three SSRs (FHTGSSR-3.4, FHTGSSR-7.5, and FHTGSSR-3.6). These confirmed hybrid progenies exhibited wide phenotypic variability with both intermediate and transgressive segregation across tree, leaf, fruit physical and biochemical parameters. Fruit parameters varied markedly in size (length: 5.59-10.13 cm; weight: 79.33-406.33 g) while qualitative variation was evident in leaf shape, fruit shape, peel, and pulp colour. Biochemical profiling revealed high variability in respect of TSS (10.30-14.80°Brix), ascorbic acid (65.00-302.00 mg/100 g), total carotenoids (0.78-9.55 mg/100 g), lycopene (0.53-9.03 mg/100 g) and antioxidant activities (DPPH: 86-95%; FRAP: 8.9-22.0 µmol Trolox/g). MGIDI analysis identified seven guava hybrids as superior multi-trait performers amongst the studied guava hybrids. Multivariate analyses helped characterize the underlying trait variability, and hierarchical clustering grouped progenies into distinct clusters. Additionally, transgressive segregation for key nutraceutical traits underscores the potential for selecting superior recombinants. Overall, this study highlights the effectiveness of hybridization between heterozygous guava genotypes in generating genetic variability, while establishing SSR markers are robust and reliable tools for confirming hybridity in crop improvement programs.