Impact of increasing irrigation intervals on Citron watermelon (Citrullus lanatus var. Citronides) development and growth

The null hypothesis suggested that the increasing irrigation intervals would not affect the development and growth of Citron watermelon (Citrullus lanatus var. Citronides). The study was conducted in autumn (February-May) 2024 and validated simultaneously. The experiment was laid out in a randomized complete block design (RCBD) with 10 replicates (n=60). Six treatments, namely, 2 (control), 4, 6, 8, 10, and 12-day irrigation intervals, were applied using a 0.5 L glass beaker per plant. The collected plant parameter data were subjected to analysis of variance through the SAS software. Mean separation was achieved using the Waller-Duncan multiple range test at the probability level of 5%. Irrigation intervals had highly significant (P ≤ 0.01) effects on dry shoot mass (DSM), stem diameter (SD), chlorophyll content (CC), vine length (VL), fruit weight (FW), fruit diameter (FD), and dry root mass (DRM) of Citron watermelon, contributing 97, 68, 53, 76, 44, 39 and 69% total treatment variation (TTV) in the respective variables. However, treatments did not significantly affect the fruit number (FN) of Citron watermelons, contributing 17%. The findings from this study indicated that a 4-day irrigation interval had beneficial effects on DSM (22435 kg), VL (1.973 m), and DRM (673 kg). The 6-day irrigation intervals yielded the highest SD (0.6533 cm), CC (82.12), FW (95296 kg), and FD (4.35 cm) values. In contrast, 12-day irrigation intervals resulted in decreased DSM (5482 kg), SD (0.4839 cm), (CC) (40.8), VL (0.6336 m), FW (2690 kg), FD (0.87 cm), and DRM (254 kg) compared to the 2-day control. Four and 6-day irrigation intervals highly improved some of the growth parameters.