Rootstocks Comparison in Grafted Watermelon under Water Deficit: Effects on the Fruit Quality and Yield

Abstract

Drought is widely recognized as one of the most significant agricultural constraints worldwide. A strategy to avoid the adverse effects of drought on crops is to cultivate high-yielding varieties by grafting them onto drought-tolerant rootstocks with a differentiated root system. Thus, the objective of this study was to evaluate fruit yield and quality, root system architecture, and water productivity of watermelon grafted onto Lagenaria siceraria rootstocks. To do so, a commercial watermelon cultivar “Santa Amelia” [Citrullus lanatus (Thunb.)] was grafted onto five L. siceraria rootstocks: ‘Illapel’, ‘Osorno’, ‘BG-48’, ‘GC’, and ‘Philippines’, which were grown under three irrigation treatments (100%, 75%, and 50% of evapotranspiration). The comparison of the L. siceraria rootstocks in the irrigation treatments demonstrated no significant effect on watermelon fruit quality parameters. The rootstocks ‘Illapel’, ‘Osorno’, and ‘GC’ significantly improved the fruit number and yield (total fruit weight) under water deficit. Similarly, ‘Illapel’, ‘Osorno’, and ‘GC’ consistently showed statistical differences for root system architecture traits compared to ‘BG-48’ and ‘Philippines’. Based on these results, we concluded that the used L. siceraria rootstocks did not affect the fruit yield and quality of grafted watermelon under water deficit. This study may help adjust the amount of applied water for watermelon production where L. siceraria rootstocks are utilized.

Comprehensive Assessment of Morphological Diversity in Bottle Gourd (Lagenaria siceraria) Accessions: A Focus on Roots and Morpho-Agronomic Traits

“…The trial was conducted in San Fernando Province (34 • 36 ′ 42.2 ′′ S 70 • 59 ′ 26.1 ′′ W), Chile, with an average temperature of 18.62 • C, a relative humidity of 50.6%, and a solar radiation level of 18.27 Mj/m 2 . The incorporation of nutrients was performed by fertigation, following the recommendation described by Crawford and Abarca [28], with minor modifications as mentioned by Morales et al [11]. Three plants from each plot or replicate were sampled at the center of each experimental unit for quantitative scoring.…”

“…Additionally, the seeds of this crop offer a rich source of essential amino acids and oil, which is why certain varieties of bottle gourd are specifically cultivated for their seeds [1,7,8]. Beyond its medicinal and culinary applications, bottle gourd also serves as a rootstock in watermelon breeding to control soil-borne diseases and the management of low soil temperature stress [9][10][11]. Notably, recent advancements have even led to successful crosses Diversity 2024, 16, 136 2 of 10 between watermelon and bottle gourd as pollen parents, resulting in the development of seedless watermelon varieties [12].…”

Potential Use of Compatible Osmolytes as Drought Tolerance Indicator in Local Watermelon (Citrullus lanatus) Landraces

“…One crop that has been shown to attract considerable consumer interest is the watermelon, which is commonly consumed as a snack or dessert in many households. However, watermelon is highly affected by drought stress [15,16]. In Botswana (and Southern Africa as a whole), the watermelon has a rich diversity that ranges from wild to cultivated varieties.…”

Joint transcriptomic and metabolomic analysis provides new insights into drought resistance in watermelon (Citrullus lanatus)

“…Leaf water loss strongly affects photosynthesis and reduces the capacity of plants to synthesize nutrients (Sun et al, 2022). Drought can also arrest watermelon fruit development, which affects fruit production and ripening and thereby reduces yield (Morales et al, 2023). When drought occurs, the size of the fruit may decrease, or fruit growth may be stunted, which can affect the taste, sweetness, and nutritional value of the fruit, reduce sales value and market competitiveness, and lead to economic losses for farmers and producers (Morales et al, 2023).…”

“…Drought can also arrest watermelon fruit development, which affects fruit production and ripening and thereby reduces yield (Morales et al, 2023). When drought occurs, the size of the fruit may decrease, or fruit growth may be stunted, which can affect the taste, sweetness, and nutritional value of the fruit, reduce sales value and market competitiveness, and lead to economic losses for farmers and producers (Morales et al, 2023). Previous research has shown that after 8 days (d) of drought stress during the watermelon seedling stage, the relative water content (RWC) of dry watermelon cultivars Y34 (drought-sensitive material) and M20 (tolerant material) significantly decreased by 38.78% and 13.68%, respectively, but the MDA content increased by 83.05% and 40.89%, respectively.…”