and may develop a slit in the lesion. Severely affected plants may result in a significantly smaller bulb size and a blighted appearance. The Botrytis Leaf Blight pathogen survives the winter much like White Rot does, as sclerotia (a small mass of fungi capable of thriving in hostile conditions). Such sclerotia is responsible for spreading the pathogen and infecting crops as it has been observed to infect leaves and bulbs of sprouted crops. Pathogens stored on the surface of the soil may produce asexual spores called conidia which may further infect crops. Botrytis Leaf Blight thrives in wet and cold temperatures but can still infect outside of these conditions. Onion Downy Mildew Onion Downy Mildew is a disease that is caused by the oomycete Peronospora destructor. It is a foliar disease, and causes leaf to become pale green, then tan, brown or yellow and finally collapse. The fungus is extremely infectious to white onion crops and can often be first observed by patterns of yellowing within a field of onion crops. Such patterns often correspond to the direction of the prevailing winds, enlarging as the disease progresses. On individual plants, signs of Peronospora Destructor can be visible, as fine, furry growths that have a greyish white colour. These growths are susceptible to further infection by diseases such as Purple Blotch of Onion or Stemphylium Leaf Blight of Onion, and if infected, can produce purple pigmentation of lesion and dark spores. The Peronospora Destructor pathogen only produces spores in live hosts, and releases spores at night, when there are cold temperatures and easily be blown across crops and infect other plants. Overwintering spores of Onion Downy Mildew are known as oospores which can be found in volunteer onions, cull piles and in infected onion bulbs. The disease can be found worldwide, but favours humid climates as it requires moisture for infection of hosts. It is most prevalent in late Spring and throughout Summer. Planting of white onions There are multiple methods of planting white onions: Onion Transplants: a method by which seedlings started in the current growing period are bought and planted in one's own garden. This method often yields quick bulb growth, but the plants are more vulnerable to disease in maturity. Onion Sets: small bulbs from the previous harvest are not allowed to mature and are dried. These bulbs are used in the current season, and often grow the