Abstract: The present disclosure discloses a tobacco leaf foliar spraying substance for reducing harmful ingredients in cheroot, a method for reducing carcinogenic components in flue-cured tobacco leaves and flue-cured tobacco shreds. The tobacco leaf foliar spraying substance contains a lotus leaf extract, the harmful chemical ingredients comprise N-nitrosonornicotine, 4-(N-methyl-nitrosamine)-1-(3-pyridinyl)-1-butanone, N-nitrosoanabasine and N-nitrosoanatabine. Foliar spraying is performed on a fertile field by using the lotus leaf extract before tobacco leaves are harvested and modulated, which not only significantly promotesagronomic characters and economic traits of tobacco and alleviates tobacco leaf browning but also effectively reduces harmful chemical ingredients unique to tobacco leaves, such as nitrosamine and nicotine.

Abstract: A vitrification device for gametes or embryos, wherein, the vitrification straw comprises: a loading rod, wherein the loading rod is a metal rod; a loading strip, wherein, the loading strip is connected with one end of the loading rod. According to the present invention, the loading rod is arranged as metal rod, which avoids embrittlement fracture caused by sudden temperature change when the loading rod is taken out of liquid nitrogen, moreover, the ice crystals that form on gametes or embryos when the loading rod floats out of the surface of liquid nitrogen, affecting the safety of gametes or embryos, the metal material used by this invention can increase the weight of the loading rod, preventing it from floating up in the liquid nitrogen, hence improve safety of gametes or embryos.

Abstract: A vitrification device for gametes or embryos, wherein, the vitrification straw comprises: a loading rod, wherein the loading rod is a metal rod; a loading strip, wherein, the loading strip is connected with one end of the loading rod. According to the present invention, the loading rod is arranged as metal rod, which avoids embrittlement fracture caused by sudden temperature change when the loading rod is taken out of liquid nitrogen, moreover, the ice crystals that form on gametes or embryos when the loading rod floats out of the surface of liquid nitrogen, affecting the safety of gametes or embryos, the metal material used by this invention can increase the weight of the loading rod, preventing it from floating up in the liquid nitrogen, hence improve safety of gametes or embryos.