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Santiago García-Martínez, Adrián Grau, Aranzazu Alonso, Fernando Rubio, Pedro Carbonell, and Juan J. Ruiz

obtain acceptable harvests despite intense virus incidence conditions. Nevertheless, important decreases in yield have been reported for this breeding line, ranging between 40% and 50% at low virus incidence conditions ( García-Martínez et al., 2012

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Timothy Coolong

exception of ‘Precious II’ and to a lesser extent ‘Enterprise’, the decrease in yield in the fall compared with spring was not closely associated with virus infection. In fact, overall incidences of virus in both years in the fall were low for the region and

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Santiago García-Martínez, Adrián Grau, Aranzazu Alonso, Fernando Rubio, Pedro Carbonell, and Juan J. Ruiz

(five or more locules), flattened and strongly ribbed, green shoulder, and red flesh. The melting texture and mild flavor of these fruits makes them highly valued in salads. However, the incidence of several viruses as Tomato mosaic virus (ToMV

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Ricardo Goenaga, Adolfo Quiles, and A. Graves Gillaspie

genotypes, grain yield was significantly higher in 2003 than in other years. This response was probably the result of less virus incidence resulting from plants not being inoculated in 2003 ( Table 4 ). ELISA results showed that in 2003, only 8% of all plots

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Giseiry Rosa-Valentín, Linda Wessel-Beaver, and Jose Carlos V. Rodrigues

, Enfield, NH Bananej, K. Vahdat, A. 2008 Identification, distribution and incidence of viruses in field-grown cucurbit crops of Iran Phytopathol. Mediterr. 47 247 257 Bos, L. Parlevliet, J.E. 1995 Concepts and terminology in plant/pest relationships: Toward

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Santiago García-Martínez, Adrián Grau, Aranzazu Alonso, Fernando Rubio, Manuel Valero, and Juan J. Ruiz

The incidence of several viral diseases such as those caused by Tomato mosaic virus (ToMV) and Tomato spotted wilt virus (TSWV) makes tomato landrace cultivation practically nonviable in many areas of southeastern Spain, especially in open

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Nihat Guner, Zvezdana Pesic-VanEsbroeck, Luis A. Rivera-Burgos, and Todd C. Wehner

States are Florida, California, Texas, Georgia, and North Carolina ( USDA, 2017 ). Production increased from 1.2 million Mg in 1987 to 5.1 million Mg in 2017, with a farm value of $579 million ( USDA, 2017 ). Plant diseases caused by viruses are a major

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E. Fava, D. Janik, C. Madramootoo, and K.A. Stewart

Production of red bell peppers (Capsicum annuum L. cv. King Arthur) is relatively new to Quebec, and management techniques need to be further developed in terms of insect and disease control as well as fertigation techniques. The purpose of the experiment was to compare the fertigation of peppers using either the conventional method (weekly fertigation) or fertigation based on the readings of the SPAD 502 chlorophyll meter. The experiment compared the effects of these fertigation treatments, with respect to insects and diseases, on either a silver or black mulch. The study done in 1995, demonstrated that using the chlorophyll meter saved 28 kg N/ha compared to the weekly fertigated plants. However, this decrease did not affect the population of insects or the disease incidence on the plants. The main differences occurred between the black and silver mulch treatments for aphid populations. Plants on silver mulch had significantly lower numbers of aphids than the other treatments. Plants on black mulch also had low aphid population compared to plants grown on bare soil. The relationship between silver mulch and viruses or tarnished plant bug were not as apparent. However, the viral infections and tarnished plant bug populations on the plants tended to be lower than those on most of the black mulch treatments. Sunscald was not influenced by mulch or fertigation treatments. This may be partly attributed to the amount of leaf area. The number of fruit invaded by European corn borer was too low to draw any conclusions. Blossom end rot, sclerotinia, and bacterial spot were not present in the field in the 1995 season. The results from the 1996 season should further elucidate these results.

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A.A. Csizinszky, D.J. Schuster, and J.E. Polston

Field studies were conducted for three seasons, Fall 1994, Spring 1995, and Fall 1995, on the effect of ultraviolet (UV)-reflective films (mulches) on the silverleaf whitefly (Bemisia argentifolii Bellows and Perring), the incidence of tomato mottle virus (ToMoV), and on fruit yields of staked, fresh-market tomatoes (Lycopersicon esculentum Mill.). The UV-reflective mulches were metallized aluminum (aluminum) and painted aluminum (silver) on either black or white plastic film. The aluminum and silver mulches were evaluated with and without a white (fall) or black (spring) 25-cm-wide painted band in the bed center. Controls were the conventional white (fall) or black (spring) polyethylene mulches. Highest reflected energy (μmol·m–2·s–1) to the plants at 15 cm from the mulch surface was measured on the aluminum mulch with or without a white painted band. Lowest energy was reflected from the white or black controls and from silver on black mulches with or without a black painted band. Whitefly populations in the fall were lower (P ≤ 0.05) on the aluminum than on the silver mulches. In the spring, when whitefly populations were low, whiteflies were more numerous on the black control and silver on white, than on the aluminum mulches. In the fall seasons, the proportion of plants with symptoms of ToMoV transmitted by the silverleaf whitefly were higher on the controls than on the aluminum mulch. In the spring, the proportion of plants with symptoms was not affected by mulch treatments. Yields in the fall were similar with UV-reflective or white control mulches. In the spring, fruit size and marketable yields were greater (P ≤ 0.05) on plants with silver on white mulch than on the control black mulch.

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Cecilia E. McGregor, Douglas W. Miano, Don R. LaBonte, Mary Hoy, Chris A. Clark, and Guilherme J.M. Rosa

.L. Fuentes, S. Salazar, L. 2003 Sweet potato virus disease (SPVD): Distribution, incidence, and effect on sweet potato yield in Peru Plant Dis. 87 297 302 Hattori, T. Nakamura, K. 1988 Genes coding for