Water-soaked, \"oily\" areas on the underside of the cotyledons or seedling leaves often paralleling the veins with a yellow halo are characteristic symptoms. The infected areas dry up and become elongated, angled, black, necrotic patches. Some seedlings will collapse and die immediately from infection. Others can retain the bacterial infection and will not exhibit symptoms until fruit set. Because the vines do not drop their leaves when infected with Paracidovorax citrulli, the lesions are difficult to see. The lesions tend to be small, dark, and angled. Leaf lesions are significant reservoirs of bacteria for fruit infection. Leaf lesions will usually be observed at temperatures above 90 degrees Fahrenheit. Stems, petioles, and roots are not infected, and thus do not show symptoms. Bacteria from leaf lesions can spread and infect developing fruit. Infection of fruit occurs at flowering and early fruit set. Two- to three-week-old developing fruit that has not formed a wax layer is most susceptible to Paracidovorax citrulli infection. Once the fruit matures and develops a wax layer, it is more difficult for the bacteria to invade the fruit. The diagnostic symptom of bacterial fruit blotch is a dark green stain or blotch on the upper surface of the developing fruit. The blotch may be 0.5 inch in diameter at first, but will rapidly expand to cover the entire fruit surface within a week if environmental conditions are favorable. The bacteria infection does not extend into the meat of the melon, but will cause the rind to rupture, enabling infection by secondary pathogens that cause the fruit to rot.