Evaluation of Sustainable Management Practices to Promote Healthy Growth of Woody Ornamentals

Madhav Parajuli, Tennessee State University


Woody ornamental nursery industry is an important agriculture sector in the United States. Major losses in this industry are caused by soilborne pathogens and insect pests such as ambrosia beetles and flatheaded borer. Biotic (soilborne pathogens) and abiotic (flood and drought) stress factors are considered to predispose field nursery tree crops to beetle and borer attacks. The goal of this study was evaluation of sustainable management practices to promote healthy growth of woody ornamentals. Legume cover crop (crimson clover) significantly reduced root rot diseases of red maple caused by Phytophthora nicotianae, Phytopythium vexans or Rhizoctonia solani, improved crop growth, increased soil organic matter and total nitrogen and stimulated antagonistic Pseudomonad population count. In another study, mixture of legume (crimson clover) and grass (triticale) cover crop demonstrated superior control of soilborne diseases of red maple caused by above mentioned pathogens compared to sole use of crimson clover and triticale and the high seeding rate (1.5×low seeding rate) of cover crop was effective than low seeding rate. Exposure of plants to biotic stress (soilborne pathogen), or drought stress did not predispose trees to flatheaded borer and ambrosia beetle attacks. When exposed to flooding, ambrosia beetle attacks were recorded only in flood intolerant tree species (flowering dogwood and redbud), while there was no attack in flood tolerant red maples. Preventative application of Acibenzolar-S-methyl (ASM, both drench and foliar applications) reduced ambrosia beetle attacks, and colonization in simulated flood stressed dogwood. These findings can be included in integrated disease and insect pest management programs.

Subject Area

Plant sciences|Plant Pathology|Agriculture

Recommended Citation

Madhav Parajuli, "Evaluation of Sustainable Management Practices to Promote Healthy Growth of Woody Ornamentals" (2023). ETD Collection for Tennessee State University. Paper AAI30690956.