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Phytophthora crown and root rot, incited by Phytophthora capsici, is an important and limiting disease in bell pepper (Capsicum annuum) production in many vegetable-producing areas of the United States. Soilborne oospores initiate disease when conditions are favorable, and polycyclic production of sporangia and zoospores occurs on infected plant tissue during the production season. Raised-bed plant culture, resistant cultivars, and oomycete-specific fungicides are commonly used to manage P. capsici. The objective of this study was to evaluate four bell pepper cultivars and four experimental breeding entries (collectively termed entries) for resistance to P. capsici in Michigan (MI) and New Jersey (NJ) and to determine the effect of a fungicide program on plant health and yield. The pepper cultivars included Camelot X3R (susceptible), Aristotle (intermediately resistant), and Paladin and Archimedes (resistant) for comparison. Disease symptoms included plant wilting and sunken necrotic stem lesions. In NJ, blighting of stems and foliage was also observed. In MI, >90% of the susceptible ‘Camelot X3R’ plants in the untreated plot wilted and died in both years of the study. All other entries had <10% plant wilting and death in 2014. In 2015, ‘Archimedes’ and ‘Paladin’ had <10% wilt and plant death; ‘Aristotle’, AP4835, 13SE12671, and AP4841 had 10% to 30% symptomatic plants. The fungicide program reduced disease to <10% for all entries except ‘Camelot X3R’ in 2014 and ‘Aristotle’ and ‘Camelot X3R’ in 2015. In NJ, ‘Paladin’, ‘Aristotle’, and ‘Camelot X3R’ (2014) and ‘Archimedes’, ‘Aristotle’, and ‘Camelot X3R’ (2015) had >30% plant wilting and death in the untreated plot. In the fungicide-treated plot, AP4841, AP4835, and AP4839 (2014), and AP4839 (2015) had <10% of plants with disease symptoms; ‘Camelot X3R’ and ‘Aristotle’ had >40% plant wilting and death in both years. In MI, marketable yield for ‘Paladin’ in fungicide-treated and untreated plots was significantly higher than the other entries in both years (P < 0.05). AP4839 was the highest yielding entry in NJ in the untreated plot, and AP4839 and ‘Archimedes’ were highest yielding in the fungicide-treated plot in 2014 and 2015, respectively. Fruit size for 13SE12671 was the largest among entries in both locations. There was no entry × fungicide program interaction in MI.

Sweet basil (Ocimum basilicum L.) is a globally cultivated and consumed herb known for its unique aroma and flavor. Sweet basil grows best in warm temperatures, and productivity and marketability decrease when grown under cool conditions (<10 °C). Silicon (Si) is not considered an essential plant nutrient, but it can be beneficial to Si macroaccumulator plants by alleviating several biotic and abiotic stresses. Recent studies have shown that some microaccumulator species may also benefit from Si. In this study, we examined the effects of different levels (0, 25, and 75 ppm Si) of Si amendments on hydroponic basil grown at 23 °C. Si (75 ppm) significantly increased shoot height and weight with no negative impact on plant morphology. All Si-treated basil plants absorbed Si in small quantities and affected the uptake of phosphorus, magnesium, sulfur, iron, manganese, copper, zinc and molybdenum. After an unintentional frost event, basil plants treated with 75 ppm had significantly higher survival rates and reduced cold injury symptoms. We concluded that Si amendments can have a positive impact on hydroponically grown sweet basil, and that such amendments may reduce plant damage due to occasionally cooler growing temperatures.