Advances in Research on Phytophthora capsici on Vegetable Crops in The United States

Abstract

Since L. H. Leonian's first description of Phytophthora capsici as a pathogen of chile pepper in 1922, we have made many advances in our understanding of this pathogen's biology, host range, dissemination, and management. P. capsici causes foliar blighting, damping-off, wilting, and root, stem, and fruit rot of susceptible hosts, and economic losses are experienced annually in vegetable crops including cucurbits and peppers. Symptoms of P. capsici infection may manifest as stunting, girdling, or cankers for some cultivars or crops that are less susceptible. P. capsici continues to be a constraint on production, and implementation of an aggressive integrated management scheme can still result in insufficient control when weather is favorable for disease. Management of diseases caused by P. capsici is currently limited by the long-term survival of the pathogen as oospores in the soil, a wide host range, long-distance movement of the pathogen in surface water used for irrigation, the presence of fungicide-resistant pathogen populations, and a lack of commercially acceptable resistant host varieties. P. capsici can infect a wide range of hosts under laboratory and greenhouse conditions including cultivated crops, ornamentals, and native plants belonging to diverse plant families. As our understanding of P. capsici continues to grow, future research should focus on developing novel and effective solutions to manage this pathogen and prevent economic losses due to the diseases it causes.

Perlakuan Benih Cabai (Capsicum annuum L.) dengan Rizobakteri secara Tunggal atau Kombinasi dapat Mengendalikan Phytophthora capsici dan Meningkatkan Pertumbuhan Tanaman

“…Penyakit busuk phytophthora juga merupakan penyakit penting di beberapa negara. Granke et al (2012) menyebutkan bahwa patogen ini telah tersebar di beberapa daerah di Amerika dan dunia. Kehilangan hasil akibat serangan P. capsici pada tanaman labu siap panen seluas 32 hektar mencapai 90% di Michigan.…”

Effect of Trichoderma on Growth and Sporangia Production of Phytophthora capsici

“…When favorable environmental conditions occur under rainfall or irrigation, P. capsici produces thousands of sporangia in free water, releasing 20 to 40 zoospores each. All zoospores have the potential to start a new infection (Granke et al, 2012).…”

Evaluation of Selected Bacterial Endophytes for Biocontrol Potential against Phytophthora Blight of Bell Pepper (Capsicum annuum L.)

“…The wide host range of P. capsici consists of more than 45 species of crops and weeds belonging to 14 families [7][8][9][10]. The pathogen is a heterothallic, soil-borne oomycete (water-mold) characterized by asexually produced motile, biflagellate zoospores and sexually produced thick-walled oospores.…”

“…The pathogen can survive for several years in the soil in the form of oospores even in the absence of susceptible crops and initiate infection when a host plant becomes available. The pathogen infects the entire plant causing symptoms such as foliar blight, stem canker, fruit, crown, and root rots [3,7,11]. Disease development is favored by warm temperatures, high rainfall or irrigation, and poor soil drainage [8].…”

“…The disease is managed mainly by crop rotation, application of chemical fungicides such as metalaxyl or mefenoxam, and management of irrigation water [12][13][14][15]. However, it is difficult to manage Phytophthora diseases because of the long-term survival of oospores in the soil, wide host range, and long-distance movement of the pathogens through soil and water [6,7]. Lack of resistant crop varieties with acceptable agronomic traits [16,17], and the rise of new aggressive phytophthora strains resistant to chemical fungicides [6] are additional challenges for the management of phytophthora blight in vegetables.…”