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ABSTRACT. Mexican agriculturists have recently noticed strong increases of mite infestations in papaya (Carica papaya L. 1753) orchards. A list of mite species associated with papaya leaves was constructed to determine the species responsible for high infestations and to identify predaceous mites as potential biological control agents. Mites were collected from three foliage strata (high, middle and low), in seven municipalities of central Veracruz State. Leaves were processed by washing and sieving. Identified species included four tetranychids: Eotetranychus lewisi (McGregor 1943) (Banks 1905), with the first two species being the most abundant. The vagrant eriophyid Calacarus citrifolii Keifer 1955 was collected in three municipalities, in the low stratum. Neither the broad mite, Polyphagotarsonemus latus (Banks 1904), nor the carmine spider mite, Tetranychus cinnabarinus (Boisduval 1867), were collected, although these species were previously recorded from this area. None of the Phytoseiid species found can be considered a recently established species; their potential as biological control agents is discussed.

A b s t r a c t. The purpose of this study was to evaluate growth, chlorophyll content, and photosynthesis in Jatropha at different levels of soil moisture. Plants were cultivated in containers and the treatments of the soil water content evaluated were: 0% (without watering), 20, 40, 60, and 80% soil water content. Plant height was statistically similar for all treatments, but the number of leaves differed significantly. Total dry matter and chlorophyll at 40, 60, and 80% soil water content were statistically similar, but different from 0 and 20% soil water content. Leaf area at 40, 60, and 80% soil water content was statistically different from 0 and 20% soil water content. The photosynthetic rate, transpiration and stomatal conductance at 60 and 80% soil water content were statistically similar but different from 0 and 20% soil water content. Water stress affected growth, chlorophyll content, photosynthetic rate, transpiration, and stomatal conductance.K e y w o r d s: Jatropha, water stress, biodiesel, photosynthesis, Mexico

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Es posible que exista tolerancia al virus de la mancha anular del papayo (PRSV-p) en plantas nativas de Carica papaya. Se evaluó la respuesta de 13 accesiones (Acc) de papayo nativo y la variedad Maradol roja respecto a la incidencia y severidad del PRSV-p, inoculado con el insecto vector Aphis nerii, y su relación con el manejo de la planta observado durante su colecta. Las Acc se colectaron en estado silvestre, en traspatio o cultivadas. A los tres meses de edad se inocularon las plantas con el virus. Se evaluó semanalmente la incidencia y severidad en nueve ocasiones. Las Acc 203 y 205 mostraron el menor índice de severidad (1.0), seguidas de 147a y 60 (con 1.7), 94a (2.0) y 197a (2.2); las Acc 64a (2.5) y 150 (2.8) alcanzaron una severidad intermedia, seguidas de la 65 y 210b (con 3.3), y de 80, 169 y 188a (con 4.3). La var. Maradol roja presentó el mayor índice de severidad (4.8). La severidad promedio en las Acc colectadas en manejo silvestre fue significativamente menor (P = 0.032) que en Maradol roja, aunque no fue diferente en las Acc que provenían de manejo de plantaciones cultivadas o de traspatio. Es posible que entre las Acc silvestres se encuentren genes de tolerancia al PRSV-p.

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