外源5-氨基乙酰丙酸对番茄成熟过程中果实品质和矿质元素含量的影响

5-氨基乙酰丙酸(ALA)为高等植物中叶绿素等卟啉类化合物的生物合成前体，在促进作物生长、增强抗逆性及提高产量方面发挥着重要作用。为探究ALA对番茄果实成熟过程中品质和矿质元素含量的影响，本研究以原味1号品种为试验材料，向绿熟期番茄果实表面涂抹不同浓度(0、50、100、200、300 mg·L^-1)ALA溶液，筛选出促进设施栽培番茄成熟及品质形成的最佳ALA施用浓度，并进一步研究其对设施番茄果实成熟过程中硬度、可溶性固形物以及矿质元素含量的影响。结果表明，外源ALA通过降低果实硬度促进了果实的成熟，并通过提高番茄果实中可溶性固形物含量提升了果实品质。另外，在坐果后40 d,200 mg·L^-1ALA处理的K、Ca和Fe元素含量分别比对照提高了21.82%、56.25%和12.86%，但P、Mg和Cu元素含量分别比对照降低了9.92%、21.74%和25.00%。相关性分析结果表明，可溶性固形物含量与K含量呈正相关关系，与Cu含量呈负相关关系；果实硬度与K含量呈负相关关系。成熟期番茄果实中P含量与Cu含量呈正相关，与Mn、K和Ca含量呈负相关...

Effects of Exogenous 5-Aminolevulinic Acid on Fruit Quality and Mineral Element Contents of Tomato During Ripening

5-Aminolevulinic acid （ALA）， a precursor of porphyrin compounds biosynthesis， such as chlorophyll. In higher plants， ALA plays an important role in promoting plant growth， enhancing stress resistance and improving crop yield. The overall objective of this research was to explore the effects of exogenous ALA on the quality and mineral element contents of tomato fruit during ripening. Tomato（Solanum lycopersicum cv. Yuanwei No.1） fruits were applied with different concentrations of ALA （0， 50， 100， 200 and 300 mg·L^-1） on the surface at the mature green fruit stage， and the optimal ALA concentration which improved the quality of the facility cultivated tomato fruit was selected. Moreover， the firmness， soluble solids and mineral elements changes during the ripening of tomato fruit were further studied. The results indicated that exogenous ALA treatments promoted fruit ripening by reducing fruit firmness， and improved fruit quality by increasing the content of soluble solid of tomato fruit. In addition， at 40^th day after fruit setting， the contents of K， Ca and Fe increased by 21.82%， 56.25% and 12.86% under 200 mg·L^-1 ALA treatment compared with control， respectively. But the contents of P， Mg and Cu were reduced by 9.92%， 21.74% and 25.00%， respectively. The results of correlation analysis showed that soluble solid content had significantly positive correlation with K content， but had significantly negative correlation with Cu content， and firmness had significantly negative correlation with K content. P content was positively correlated with Cu content， and negatively correlated with contents of Mn， K and Ca in tomato fruits at maturity. K content was positively correlated with contents of Ca and Zn. Mg content was negatively correlated with Zn content. The results of principal component analysis showed that K and Mg were the characteristic elements in tomato fruit after ALA treatment. In conclusion， applying an appropriate concentration of exogenous ALA（200 mg·L^-1）during ripening of tomato fruit not only decreased the fruit firmness and enhanced soluble solid content of the fruit， but also regulated the absorption and accumulation of mineral elements. These results provide theoretical reference for mechanism of ALA regulating the mineral nutrients absorption of tomato fruit， and new ideas for the cultivation technology of high-quality tomato.