The goal of the present study was to determine whether grafting of watermelon on gourd rootstocks could improve alkalinity tolerance and to investigate the physiological and morphological response mechanisms of the grafted plants under different pH levels. The experiment was carried out in a climate chamber to investigate growth, leaf chlorophyll content (SPAD), leaf area, stem length, shoot and root dry weight, root length, electrolyte leakage, leaf mineral composition, total chlorophyll and carotenoid contents. Two watermelon cultivars (Crimson tide, CT, and Crisby) were grafted onto three commercial Cucurbita maxima × C. moschata hybrid rootstocks under climate-chamber conditions (Strong tosa, ST, Ercole and Nun 9075). The grafted seedlings were transplanted onto 8 L continuously aerated pots containing nutrient solution with two different pH levels (8.5 and 6.5) and replicated three times. The results showed that in both grafted and non-grafted plants, there was a substantial reduction in shoot and root biomass production at high pH levels. At high pH level, the significantly highest leaf area, stem length, SPAD, concentration of P, Ca, S and Mn in leaf tissues were recorded in graft combination ‘Crisby/Ercole’, whereas the significantly highest concentration of Fe in leaf tissues, shoot dry weight were recorded in graft combination ‘Crisby/Nun 9075’. Moreover, at high pH, the significantly highest concentration of Mg and Cu in shoot under high pH levels was significantly found in graft combination of ‘CT/ST’. These results suggest that the use of interspecific Cucurbita maxima × C. moschata hybrid rootstocks can improve crop performance in watermelon plants under alkaline conditions.

本研究的目的是确定在葫芦砧木上嫁接西瓜是否可以提高耐碱性，并研究在不同pH水平下嫁接植物的生理和形态响应机制。该实验在气候箱中进行，以研究生长，叶片叶绿素含量（SPAD），叶面积，茎长，枝条和根干重，根长，电解质渗漏，叶片矿物质组成，总叶绿素和类胡萝卜素含量。将两个西瓜品种（Crimson潮汐，CT和Crisby）嫁接到三个商业南瓜最大 × 南瓜（C.  moschata）上气候室条件下的杂种砧木（强土佐，ST，Ercole和Nun 9075）。嫁接的幼苗被移植到装有两个不同pH值（8.5和6.5）营养液的8 L连续充气花盆中，并重复3次。结果表明，无论是嫁接植物还是非嫁接植物，在高pH值条件下，枝条和根生物量的产量均显着降低。在高pH值条件下，嫁接组合“ Crisby / Ercole”记录了叶片组织中叶面积，茎长，SPAD，P，Ca，S和Mn含量显着最高，而叶片组织中Fe的含量最高，在移植物组合“ Crisby / Nun 9075”中记录了茎干重量。而且，在高pH下 在'pH / ST'的嫁接组合中，在高pH值条件下，芽中Mg和Cu的浓度最高。这些结果表明使用种间笋瓜 ×  C.南瓜混合砧木可以提高在碱性条件下在植物西瓜作物性能。