Method for protecting plant life from injury due to frost or sub- freezing temperatures

摘要

A method of protecting plant life from injury due to frost or sub- freezing temperatures which comprises applying to the plant an effective, but non-phytotoxic amount, having regard to the plant being treated of a compound of the formula: ##STR1## wherein R.sub.1 is lower- alkyl;P PR.sub.2 is selected from the group consisting of:P P A. lower-alkyl, andPPB. 2-hydroxy alkyl of 3 to 18 carbon atoms; andPPA is selected from the group consisting of:PPA. alkyl of 3 to 13 carbon atoms,P P B. 2-hydroxy-lower alkyl,PPC. lower alkenyl, P PD. substituted phenyl, substituted by substituents selected from the group consisting of:PPI. p- nitro,P PIi. halo, andPPIii. lower alkoxy, ##STR2## wherein R. sub.3 and R. sub.4 are each independently selected from the group consisting of:PPI. hydrogen,P PIi. alkyl of 2 to 18 carbon atoms,PPIii. substituted phenyl, PPIv. benzyl,PPV. lower-alkoxy carbonyl, andPP Vi. 2-hydroxy-lower alkyl; and ##STR3## wherein R. sub.5 is lower alkyl;PP R.sub.6 is selected from the group consisting of:PPI. alkyl of 3 to 8 carbon atoms, PP Ii. 2-hydroxy lower alkyl, andPP Z .sup.- is an agriculturally acceptable anion.