INTERACTION EFFECT OF GENOTYPE AND SALINITY LEVELS ON AGROMORPHOGENIC, PHYSIOLOGICAL AND NUTRITIONAL TRAITS OF TOMATILLO (Physalis ixocarpa Brot./P. philadelphica Lam.)

Abstract

The present study was conducted as a pot experiment in order to observe the performance of tomatillo (Physalis ixocarpa Brot./P. philadelphica Lam.) genotypes under different levels of salinity treatment. The experiment was conducted beside the area of the net house of Department of Genetics and Plant Breeding, Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh, during the period of November, 2017 to March, 2018. A two factorial Completely Randomized Design (CRD) experiment was conducted which included four tomatillo genotypes (Factor A) viz. G 1 (SAU tomatillo 1), G 2 (SAU tomatillo 2), G 3 (PI003), G 4 (PI004) and three salinity treatments (Factor B) viz. T 1 (Control), T 2 (8 dS/m), T 3 (12 dS/m) and was outlined with three replications. Seedlings of 21 days old were transplanted into main plastic pots and two salinity treatments, 8 dS/m and 12 dS/m were started to apply after 7 days of transplanting. The observed results showed that both of four tomatillo genotypes and three salinity treatments had their independent significant influence and also had significant influence in their interaction effect between different agromorphogenic, physiological and nutritional traits. Almost all agromorphogenic and physiological traits responded negatively (%Reduction), except endogenous Na ion and proline content whereas nutritional traits like, %Brix, titratable acid and vitamin-C content, except fruit pH responded positively (%Increase) under the increased level of salinity treatments. From the observed results of the accomplished study, considering yield and its contributing characters like, number of fruits per plant, average fruit length, diameter, fruit weight as well as yield per plant, the best salt tolerant genotypes of tomatillo were genotype G 1 and G 3 under both slightly and moderately salinity stresses. These two also showed minimum endogenous Na and maximum K + ion content along with minimum reduction in leaf area index. The maximum amount of proline content was observed in genotype G 4 while G 1 showed the maximum increase percentage. The maximum reduction in days to maturity was found in genotype G 1 and G 4 . Considering the increased percentage of nutritional traits like, %Brix, titratable acid and vitamin-C content, the best salt tolerant genotypes of tomatillo were genotype G 3 along with G 4 and G 1 + . Thus, genotype G 3

and G 1 could be recommended for further trial in Southern region of Bangladesh. And, genotype G 2 and G 4 could be served as parent materials for further hybridization or genetic transformation program along with G 3

and G 1 . +