Three linked autosomal loci were studied in cucumbers: fruit color (dark vs. light), tendril size (long vs. reduced) and fruitin
g (normal vs. early). Pure breeding early fruiting light cucumbers with long tendrils were mated to pure breeding normal fruiting dark cucumbers with reduced tendrils. The F1 were testcrossed and the testcross progeny are given below. Time to Fruit Tendril Size Fruit Color Number Normal Long Dark 360 Normal Long Light 32 Early Long Light 753 Early Long Dark 28 Early Reduced Dark 24 Early Reduced Light 494 Normal Reduced Light 35 Normal Reduced Dark 975
Simple species that can tolerate the often- harsh environment become established first. These organisms help enrich the soil, allowing other species to become established. The first organisms to appear in areas of primary succession are often mosses or lichens.
