Crystalline ZIF-8 (C-ZIF-8) and amorphous ZIF-8 (Am-ZIF-8) were prepared and investigated to control the germination of Strigahermonthica, a root parasitic plant, which threatens cereal cropsproduction particularly in sub-Saharan Africa. We have demonstratedthat Am-ZIF-8 shows a better performance than C-ZIF-8 in inhibitingStriga seeds germination. This efficient performance of Am-ZIF-8materials can be attributed to the incomplete deprotonation of 2methylimidazole (2MIM) during amorphization, leading to thepresence of unsaturated Zn-N coordination with the uncoordinated -NH groups available to undergo hydrogen bonding with thestrigolactone analog GR24 forming a more stable Am-ZIF-8···GR24hydrogen bonded network. We further established that application of ZIF-8 materials generally has no adverse effects on the growth andquality of rice crops.
