As the vector of the global disease of citrus greening or huanglongbing, Asian citrus pysllids, Diaphorina citri Kuwayama (Hemiptera: Liviidae), are the greatest threat to the worldwide citrus industry. Critical to management of D. citri and huanglongbing is optimization of surveillance methodologies. Although phytophagous insects may find host plants by multimodal cues, some appear to primarily use visual cues. In this study, we examined the behavior of Asian citrus psyllids toward light from light-emitting diodes (LEDs) in the insect visible spectrum. The periodicity of attraction of psyllids to visual cues was evaluated in the field (yellow sticky traps) and laboratory (multi-colored LEDs) with a strong peak of activity during the afternoon in both the field and the laboratory (both 14:00 to 18:00 hours). In laboratory evaluations of psyllids to differently colored LEDs, strongest attraction was to LEDs emitting ultraviolet (390 nm), green (525 nm), and yellow (590 nm) light. Male and female psyllids did not differ significantly in their responses to visual cues. These findings provide the basis for formulating better traps that reflect UV and yellow light and potentially incorporate UV LEDs for monitoring psyllids and a better understanding of Asian citrus psyllid visual behavior.

Profound changes will occur from the loss of methyl bromide by the vegetable industry, since it is a key component in production systems. Many growers have relied only on methyl bromide to manage soil pathogens, nematodes, and weeds. This system combined with raised beds, plastic mulch, and drip irrigation has been very effective to produce high vegetable yields. Non-chemical alternatives like solarization and organic amendments are as yet largely unproven but do offer promise of sustainable solutions free of government regulation. The objective of this research was to study the effects of long-term, large-scale use of sustainable methods utilizing soil solarization and organic amendments on weed populations, nematodes, yields and soil fertility on peppers (Capsicum annuum L.) and cucumbers (Cucumis sativus L.). The field experiment was conducted during 1998 and 1999 season in a commercial vegetable farm in Boynton Beach, FL. There were five large plots consisting of 10 beds, 610 m long (1.3 ha). Treatments consisted of: 3 years of soil solarization and organic amendment; 2 years of soil solarization and organic amendment; 2 years of soil solarization and non-organic amendment; and methyl bromide as a control. At the end of the second crop, solarized treatments had higher % weed cover and were populated primally by bermudagras (Cynodon dactylon L. Pers.) a warm weather spreading perennial weed as compared with the methyl bromide production system, dominated by redroot pigweed (Amaranthus retroflexus L.) an annual weed easier to control than bermudagrass illustrating, a weak point of a long term solarization system. Population levels of the root-knot nematode [Meloidogyne incognita (kofoid and white) chitwood] fluctuated throughout the experiment. During 1999 and 2000, the lowest numbers occurred in the conventional system with methyl bromide. However on each sampling date, numbers in at least one of the sustainable systems were statistically similar to those in the methyl bromide-treated plots. Marketable yields of peppers appeared to be similar within the production systems for the 1998-1999 season. On all testing dates, organic matter, pH, and Mehlich 1-extractable P, K, Ca, Mg, and Zn were higher in systems where compost was applied than in systems without compost. Manganese was not

This chapter discusses the following aspects of organic pepper (Capsicum spp.) production: transplant production, soil fertility management and nutrient budgeting (establishment of cover crops, compost application and composting, and manure application), weed management, disease management, arthropod pest management, and postharvest handling.

Methyl bromide will be unavailable to conventional vegetable growers in the year 2005, and it cannot be used by organic growers. Chemical alternatives are more expensive and may also be subject to future restrictions. Non-chemical alternatives like solarization and organic amendments are as yet largely unproven but do offer promise of sustainable solutions free of government regulation. The objective of this study was to evaluate the effects of soil-incorporated biosolids and soil solarization on plant growth, yield, and soil fertility. Main plots were a biosolids soil amendment (37 Mg·ha-1 and a non-amended control. Treated main plots had received some type of organic amendment for the previous 6 years. Sub-plots were fumigated with methyl bromide as they had been for 6 years, or non-fumigated. Non-fumigated plots were further split into solarized and non-solarized plots. Bell pepper (Capsicum annuum `X 3R Aladdin') was grown for 8 months. Nitrogen fertilization was reduced to 50% of the recommended rate in the biosolids plots due to expected N mineralization from the biosolids amendment. Plant biomass was higher in the biosolids plots compared with the non-amended plots but there were no differences in marketable pepper yields between biosolids and non-biosolids plots. Plants grown in solarized soil produced lower plant biomass and yields than the methyl bromide and non-fumigated treatments. Soil pH and Mehlich 1-extractable P, K, Ca, Mg, Zn, Mn, Fe, and Cu were higher in biosolids plots than in non-amended control plots. Soil organic matter concentration was 3-fold higher where biosolids were applied compared with non-amended soil. The results suggest that regular organic amendment applications to a sandy Florida soil can increase plant growth and produce similar yields with less inorganic nutrients than are applied in a standard fertilization program. However, methyl bromide and non-fumigated treatments produced higher yields than soil solarization.

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