Phytophthora ramorum
Detection of "P. ramorum" in watercourses has emerged as the earliest of early detection methods. This technique employs pear or rhododendron baits suspended in the watercourse using ropes, buckets, mesh bags, or other similar devices. If plants in the watershed are infected with "P. ramorum", zoospores of the pathogen (as well as other "Phytophthora" spp.) are likely present in adjacent waterways. Under conducive weather conditions, the zoospores are attracted to the baits and infect them, causing lesions that can be isolated to culture the pathogen or analyzed via PCR assay. This method has detected "P. ramorum" at scales ranging from small, intermittent seasonal drainages to the Garcia, Chetco, and South Fork Eel Rivers in California and Oregon (144, 352, and 689 mi2 drainage areas, respectively). It can detect the existence of infected plants in watersheds before any mortality from the infections becomes evident. Of course, it cannot detect the exact locations of those infected plants: at the first sign of "P. ramorum" propagules in the stream, crews must scour the watershed using all available means to find symptomatic vegetation.
Moniliophthora perniciosa
Generally, there are four major strategies that can be used for disease control of Witches’ Broom. One strategy is phytosanitation, which is the removal and destruction of diseased plant parts. This can only be conducted during dry periods, or one risks spreading the disease further. Other strategies for control are chemical control, genetic resistance and biological control. Genetic resistance is currently being researched. In order to achieve durable resistance to a specific pathogen, extensive knowledge of the genetics of specific host-pathogen interaction is required. Host-pathogen interaction for "M. perniciosa" is not fully known. Some of these strategies can be tedious and expensive, for example, 95% phytosanitation is required to achieve 50% reduction in pod loss. Among the endophytic fungi associated with cacao are many species of "Trichoderma". Several species of "Trichoderma" have been isolated from cacao and is one of the most often used biofungicides. One of the isolates, "T. stromaticum" parasitizes the saprotrophic mycelium and basidiocarps of M. perniciosa, which reduces the formation of basidiocarps by 99% when brooms are in contact with soil and 56% in brooms remaining on trees. It can reduce pod infection by 31%. This biofungicide has shown variable performance due to environmental conditions of high humidity and moisture from rainfall, which is ideal for disease development, but not necessarily ideal for optimizing biocontrol efficacy.