苦豆子生物碱对番茄生长及果实品质的影响

Effect of Sophora alopecuroides Alkaloids on Tomato Growth and Fruit Quality

【目的】通过测定植物源农药苦豆子生物碱对番茄生长发育及果实品质的影响,探讨苦豆子生物碱对番茄形态及发育的调控效应,全面了解苦豆子生物碱的生物学效应,为其科学合理使用提供依据。【方法】以番茄为供试植物,阿维菌素为对照药剂,测定苦豆子生物碱不同浓度(333.0、166.5和111.0 mg·L-1)处理对番茄植株形态、果实产量及品质指标的影响。采用盆栽试验测定苦豆子生物碱对番茄幼苗株高、茎粗、叶片总数、最大叶长和宽及叶绿素含量的影响;采用田间小区试验测定苦豆子生物碱对番茄产量、可溶性糖含量、可滴定酸含量、维生素C含量和硝酸盐含量的影响。【结果】苦豆子生物碱对番茄植株生长及果实品质具有明显的调控作用。盆栽试验结果表明,166.5 mg·L-1处理对番茄幼苗的刺激生长作用最为明显,与空白对照(清水处理)相比,每次施药后第7天,番茄的株高相对生长速率分别增加55.07%、103.03%和60.60%,茎粗净增长量分别增加31.54%、225.80%和185.45%,但叶片形态无明显变化;在333.0和166.5 mg·L-1浓度下,与空白对照相比,苦豆子生物碱处理后可使叶片叶绿素含量分别升高6.16%—13.79%和6.89%—17.12%,而111.0 mg·L-1浓度处理的番茄叶绿素含量较空白对照却下降0.60%—9.40%。田间小区产量测定结果表明,333.0、166.5和111.0 mg·L-1的苦豆子生物碱处理后,与空白对照相比,番茄第一穗果实平均单果重分别增加13.07%、20.92%和9.15%,第二穗果实平均单果重与空白对照均无显著差异,第三穗果实平均单果重分别增加12.23%、20.86%和17.27%;且166.5 mg·L-1浓度下,番茄前期产量较对照增加16.48%,而333.0和111.0 mg·L-1处理下,产量无显著增加。田间小区试验果实品质测定结果表明,在浓度为333.0和111.0 mg·L-1的苦豆子生物碱处理下,与空白对照相比,可溶性糖含量平均值明显下降,而166.5 mg·L-1处理下可溶性糖含量与对照无显著差异;在333.0、166.5和111.0 mg·L-1浓度下,可滴定酸含量平均值分别较空白对照增加37.01%、23.88%和27.16%;333.0、166.5 mg·L-1浓度的苦豆子生物碱处理后,与空白对照相比,番茄第一穗果实的维生素C含量分别下降28.06%和21.91%,第二穗分别下降27.37%和26.34%,而第三穗分别增加7.28%和7.69%,呈先降低后升高的趋势,而111.0 mg·L-1浓度下,第一、二穗果实维生素C含量较空白对照显著下降,第三穗果实维生素C含量与空白对照无显著差异;苦豆子生物碱处理后番茄果实中硝酸盐的含量与空白对照相比显著增加,且浓度越高,硝酸盐积累越多,但仍远远低于中国蔬菜硝酸盐允许量。【结论】在田间常用浓度(166.5 mg·L-1)下,苦豆子生物碱能够在番茄营养期促进生长,生殖期促进果实增产,对果实品质无不利影响,作为一类新型、安全的植物源农药,具有较好的开发应用前景。

Objective]The objective of this study is to investigate the effect ofSophora alopecuroidesalkaloids on tomato growth and development for evaluating its biological function and providing a basis for its application.[Method] Avermectins was chosen as the contrast agent. Tomato plants were sprayed with different concentrations （333.0, 166.5 and 111.0 mg·L^-1） ofS. alopecuroides alkaloids and the changes of morphology, fruit quality and yield were measured. Tomato plant height, stem diameter, the number of leaves, the length-width rate of the maximal leaves and the chlorophyll content were measured in a pot experiment. The effect ofS. alopecuroides alkaloids on tomato yield, soluble sugar content, titratable acid content, vitamin C content and nitrate content were investigated in a field plot experiment.[Result]S. alopecuroides alkaloids could regulate the plant growth and fruit quality. The pot experiment showed that the effect on stimulating growth of tomato seedlings was most obviously at concentration of 166.5 mg·L^-1. Compared with the blank control （water treatment）, 7th day after each spray, the relative growth rate of tomato plant height increased by 55.07%, 103.03% and 60.60%, respectively, net increase of stem diameter of tomato plant increased by 31.54%, 225.80% and 185.45%, respectively, but the alkaloids did not significantly influence leaf morphological factors. At concentration of 333.0 and 166.5 mg·L^-1, after sprayingS. alopecuroides alkaloids, the chlorophyll content in treated leaves increased by 6.16%-13.79% and 6.89%-17.12%, respectively, but in 111.0 mg·L^-1 treatment the chlorophyll content decreased by 0.60%-9.40% compared with blank control. Field plot experiment showed that tomatoes treated by 333.0, 166.5 and 111.0 mg·L^-1 ofS. alopecuroides alkaloids, the single fruit weight increased by 13.07%, 20.92% and 9.15%, respectively, on the first cluster compared with the blank control, did not have a significant difference on the second cluster, and increased by 12.23%, 20.86% and 17.27%, respectively, on the third cluster. At concentration of 166.5 mg·L^-1, the tomato yield was 16.48% more than blank control, and there was no significant increase in other treatments. Fruit quality results showed that at concentrations of 333.0 and 111.0 mg·L^-1, the soluble sugar content declined obviously compared with the blank control, but it did not have a significant difference in tomatoes treated by 111.0 mg·L^-1 of alkaloids. At concentrations of 333.0, 165.6 and 111.0 mg·L^-1, the mean of titratable acid content in tomatoes increased by 37.01%, 23.88% and 27.16%, respectively, compared with the blank control. At concentrations of 333.0 and 166.5 mg·L^-1, the vitamin C content decreased by 28.06% and 21.91%, respectively, on the first cluster, decreased by 27.37% and 26.34%, respectively, on the second cluster, but increased by 7.28% and 7.69%, respectively, on the third cluster, and showed a trend of increase at first and then decrease. At concentration of 111.0 mg·L^-1, the vitamin C contentdeclined on both the first and second clusters, but did not have a difference on the third cluster compared with the blank control. The nitrate content all increased compared with the blank control, and the nitrate content accumulated more as the concentration increased, but it was still far below the tomato nitrate allowance in China.[Conclusion]At the field commonly used concentration （166.5 mg·L^-1）,S. alopecuroides alkaloids could stimulate seedling growth and increase the yield of tomato remarkably, and it had no adverse influence on fruit quality.