Pumnuan J, Namee D, Sarapothong K, Doungnapa T, Phutphat S, Pattamadilok C, Thipmanee K
Department of Plant Production Technology, School of Agricultural Technology, King Mongkut's Institute of Technology Ladkrabang, Bangkok, 10520, Thailand.
Faculty of Agricultural Technology, Valaya Alongkorn Rajabhat University under the Royal Patronage, Pathumthani, 13180, Thailand.
Heliyon. 2022 Dec 25;8(12):e12589. doi: 10.1016/j.heliyon.2022.e12589. eCollection 2022 Dec.
Bruchid beetles ( and ), and maize weevil () are important insect pests during the postharvest period. Botanical insecticide is an alternative solution for controlling these insects, and long pepper () has been reported as having insecticidal potential against general insect pests. Film seed coatings with various concentrations of hexane extracts were made for mung bean () and corn () seeds. Insecticidal activities of these treatments were assessed at before and after storage period of six months, and seed germination was also evaluated. The hexane extract was subjected to analysis of the bioactive components by using Gas Chromatography-Mass Spectrometry (GC-MS). Results revealed that the hexane extract presented extreme toxicity to both bruchid beetles higher compared to maize weevil at 24 h with LC values of 5.57-6.75 and 58.04 μg⋅cm, respectively. Bruchid beetles presented significant response to ethanol, acetone and hexane extracts, whereas maize weevil showed relatively low responsibility. Film seed coating with hexane extract at 1% and 3% concentrations with six-month storage presented high insecticidal activity against bruchid beetles by more than 88% mortality but had low kill rates against maize weevil. The coated mung bean seeds presented non-seed germination effect, whereas high effect was observed on coated corn. Isolation of bioactive components demonstrated that there were 74 compounds, where pentadecane was the main compound. Film seed coating technology for mung bean seed preservation by using 1% hexane extract from long pepper fruit presented to be an extremely effective method to control bruchid beetles without any seed germination effect. It could serve as one of the green insecticides of the future.
豆象甲虫（ 和 ）以及玉米象（ ）是收获后时期的重要害虫。植物源杀虫剂是控制这些害虫的一种替代解决方案，据报道，荜拨（ ）对一般害虫具有杀虫潜力。制备了含有不同浓度己烷提取物的薄膜种子包衣，用于绿豆（ ）和玉米（ ）种子。在储存六个月前后评估了这些处理的杀虫活性，并对种子发芽情况进行了评估。使用气相色谱 - 质谱联用仪（GC - MS）对己烷提取物的生物活性成分进行了分析。结果表明，己烷提取物对两种豆象甲虫均表现出极高的毒性，在24小时时，其对豆象甲虫的LC值分别为5.57 - 6.75 μg·cm，对玉米象的LC值为58.04 μg·cm，豆象甲虫对己烷提取物的敏感性高于玉米象。豆象甲虫对乙醇、丙酮和己烷提取物表现出显著反应，而玉米象的反应相对较低。浓度为1%和3%的己烷提取物薄膜种子包衣在储存六个月后对豆象甲虫具有高杀虫活性，死亡率超过88%，但对玉米象的杀灭率较低。包衣绿豆种子未表现出种子发芽影响，而包衣玉米种子则观察到较高的发芽效果。生物活性成分的分离表明有74种化合物，其中十五烷是主要化合物。使用荜拨果实1%己烷提取物进行绿豆种子保存的薄膜种子包衣技术是控制豆象甲虫的一种极其有效的方法，且对种子发芽没有任何影响。它可作为未来的绿色杀虫剂之一。
