摘要： 为改善新疆吐鲁番极端高温天气下甜瓜生长、产量和品质,探究喷施调环酸钙(PCa)对高温胁迫下甜瓜生理生长的影响,以蒸馏水(CK)和浓度为20( PCa1),50( PCa2),100( PCa3),150 mg/L( PCa4)的PCa喷施甜瓜叶片,通过对甜瓜光合作用、活性氧含量、抗氧化酶、抗氧化物质、蔓长、茎粗、产量和品质等指标的综合分析,寻找适合该地区高温胁迫下甜瓜叶面喷施PCa的最佳浓度。结果表明,随着PCa浓度增大,甜瓜各时期叶绿素a、叶绿素b、$\mathrm{O}_{2}^{-}$、H₂O₂和茎粗逐渐升高,较CK增幅分别为9.25%~36.29%,4.25%~49.92%,21.45%~334.55%,5.36%~109.41%,2.33%~20.69%;而MDA逐渐降低,较CK降幅为7.37%~48.83%,喷施PCa提高高温胁迫下甜瓜光合作用和活性氧,降低高温对甜瓜生物膜的损害。PCa1、PCa2、PCa3处理较CK提高高温胁迫下甜瓜可溶性蛋白、可溶性糖、PRO、SOD、POD、AsA、GSH、产量、果实可溶性固形物和果实可溶性糖含量,且3个处理各指标综合比较以PCa2处理较好,喷施适宜浓度的PCa显著提高高温胁迫下甜瓜渗透调节物质、抗氧化酶、抗氧化物质及产量品质,提高了甜瓜耐热能力并实现甜瓜增产提质;PCa4处理虽提高甜瓜产量,但却降低了果实可溶性固形物和果实可溶性糖含量,高浓度PCa延迟了甜瓜生长,影响收获时甜瓜品质。因此,生产中PCa2处理是实现高温胁迫下甜瓜耐热增产提质的最佳处理,建议该地区喷施PCa的最适浓度为50 mg/L。

关键词: 甜瓜, 调环酸钙, 光合作用, 活性氧, 抗氧化系统, 高温胁迫

Abstract:

To improve the growth,yield,and quality of cantaloupe under extreme high temperature weather in Turpan,Xinjiang,the effects of spraying prohexadione-calcium(PCa)on the physiological growth of cantaloupe under high temperature stress were investigated,distilled water(CK)and PCa with concentrations of 20(PCa1),50(PCa2),100(PCa3),150 mg/L(PCa4)were sprayed on cantaloupe leaves.Through comprehensive analysis of indicators such as photosynthesis,reactive oxygen species content,antioxidant enzymes,antioxidant substances,vine length,stem thickness,yield,and quality of cantaloupe under high temperature stress,the optimal concentration of PCa suitable for foliar spraying of cantaloupe in the region was found.The results showed that as the concentration of PCa increased,the chlorophyll a,chlorophyll b, $\mathrm{O}_{2}^{-}$,H₂O₂,and stem diameter of cantaloupe gradually increased at different stages,with increases of 9.25%-36.29%,4.25%-49.92%,21.45%-334.55%,5.36%-109.41%,and 2.33%-20.69% compared to CK,respectively;and MDA gradually decreased,with a decrease of 7.37%-48.83% compared to CK,respectively.Spraying PCa increased photosynthesis and reactive oxygen species in cantaloupe under high temperature stress,reducing the damage of high temperature to cantaloupe biofilm.PCa1,PCa2,and PCa3 treatments increased the levels of soluble protein,soluble sugar,PRO,SOD,POD,AsA,GSH,yield,soluble solids content,and soluble sugar content of the fruit in cantaloupe under high temperature stress compared to CK.Among the three treatments,PCa2 treatment showed better performance in terms of various indicators.Spraying PCa at an appropriate concentration significantly improved the osmotic regulation substances,antioxidant enzymes,antioxidant substances,and yield and quality of cantaloupe under high temperature stress,enhanced its heat resistance,and achieved increased yield and quality of cantaloupe.Although PCa4 treatment increased the yield of cantaloupe,it reduced the content of soluble solids and soluble sugars in the fruit.High concentrations of PCa delayed the growth of cantaloupe and affected its quality at harvest.Therefore,PCa2 treatment in production is the best treatment to achieve heat resistance,yield increase,and quality improvement of cantaloupe under high temperature stress.It is recommended that the optimal concentration for spraying PCa in this area is 50 mg/L.

Key words: Cantaloupe, Prohexadione-calcium, Photosynthesis, Reactive oxygen species, Antioxidant system, High temperature stress

中图分类号: 

• S652