Scientists discovered the true characteristics of the twig blight disease (TBD) (Haemotonectria haematococca) in citrus plants in a recent study.
The study, titled “Morphology, phylogeny, and biology of twig blight disease (TBD) of citrus caused by Haemotonectria haematococca”, was motivated by the increase and severity of TBD infection in citrus in the country, particularly in 2006, which have put to waste the tremendous amount of pesticides used by citrus growers.
Specifically, the study identified the fungus that causes TBD, a result which hopefully can be used as baseline information in finding a cure to TBD.
TBD affects young citrus plants more than the old plants and occurs more frequently from January to April. Its symptoms include twig drying, bark hardening, twig girdling, leaf cholorosis, and defoliation. The affected twigs are often covered with pink or salmon-colored fungal propagules that usually occur in all stages of the plant during the cold season.
Funded by the Nueva Vizcaya State University (NVSU), Maejo University in Thailand, and Fulbright Philippines, the study was spearheaded by Dr. Jonar I. Yago of the Citrus Research and Resources Development Center of NVSU in Bayombong Nueva Viscaya.
Working with Yago was Dr. Kuang-Ren Chung of the Citrus Research and Education Center and Department of Plant Pathology, Institute of Food and Agricultural Sciences, University of Florida, USA.
TBD particularly afflicts the citrus commonly known as tangerine (Citrus reticulate Blanco cv. Satsuma). This mandarin orange is a small variant of citrus tree with reddish orange fruit that resembles other oranges.
Yago said that the study provided the venue to determine the exact identity of the organism that causes TBD in citrus and explored the organism’s inherent traits, form and structure, and its disease-causing mechanism.
“These are vital information needed to package a technology that can control TBD and can also be used as basis for recommending appropriate and effective TBD control strategies in citrus,” Yago also said.
“Malnutrition and unfavorable environmental conditions aggravate the disease of the citrus plant, thus it is best to keep it healthy. The actual treatment consists of pruning and burning the trim parts to prevent the spread of the fungal infection, Yago added.
Incidentally, the study won third place in the research category of the recently concluded National Symposium on Agriculture and Aquatic Resources Research and Development (NSAARRD) held in Los Baños, Laguna.
NSAARRD, a PCAARRD initiative, showcases the most outstanding contributions of individuals and institutions in the improvement of the agriculture, aquatic, and natural resources sectors through R&D.