Thanks to the work of researchers at the University of Queensland in Australia, there could be a side of guacamole to go with all the Mars potatoes. Ph.D. student Chris O'Brien successfully developed a liquid nitrogen cryopreservation technique for avocado shoot tips. It's the same kind of method used to deep-freeze human sperm and eggs. "The aim is to preserve important avocado cultivars and key genetic traits from possible destruction by threats like bushfires, pests and disease such as laurel wilt -- a fungus which has the capacity to wipe out all the avocado germplasm in Florida," O'Brien said in...