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HEMIPTERA, COREIDAE, INSECT development, OPUNTIA, and FEROCACTUS

Narnia femorata Stål (Hemiptera: Heteroptera: Coreidae) is a leaffooted bug commonly found on Opuntia and Ferocactus cacti (Cactaceae) in southern New Mexico. Although general information has been published on the biology of this species, detailed studies are limited, particularly in America north of Mexico. Therefore, we conducted a study of this bug's life history in southern New Mexico from August 2010 to May 2012, reared the bug in the laboratory, and described the immature stages. Six prickly pear cactus plants, Opuntia phaeacantlut Engelmann, and four barrel cactus plants, Ferocactus wislizeni (Engelmann) Britton & Rose, were examined weekly to record numbers of the various life stages, adult sex ratios, and behavioral activities. Adults of this apparently bivoltine species overwintered in plant debris at the bases of their host plants. They emerged in late February to deposit eggs in rows along the underside of cactus spines. Nymphs were found from late February through late December. Nymphs of the first generation were most abundant April through June on and around developing flowers of O. phaeacantha. Those of the second generation were most abundant during August and September on maturing fruit of O. phaeacantha and developing flowers and maturing fruit of F. wislizeni. The bug also was reared from egg to adult under controlled laboratory conditions on fruit and pads of O. phaeacantha at 25 ± 0.01°C under a photoperiod of 14:10 (L:D) h. The incubation period averaged 12.70 d. The five stadia averaged 3.84, 11.00, 12.12, 17.06, and 22.94 d, respectively. Instars can be distinguished readily by differences in several morphological features in addition to body size and coloration. [ABSTRACT FROM AUTHOR]

AGRICULTURAL pests, INSECT anatomy, INSECT physiology, INSECT metamorphosis, INSECT development, and DEVELOPMENTAL biology

The five immature stages of Agonoscelis puberula Stål are described and illustrated; biological notes and a new host plant, Leonotis nepefifolia (L.) are also recorded. [ABSTRACT FROM AUTHOR]

COWPEA, VIGNA, HEMIPTERA, INSECT development, CULTIVARS, DISEASE resistance of plants, and EFFECT of temperature on plants

The growth and development of Clavigralla tomentosicollis Stäl (Hemiptera: Coreidae) and Maruca testulalis Geyer (Lepidoptera: Pyralidae) were studied under laboratory conditions using three cultivated Vigna varieties (IT84E-124, TVu 1890, MRx 10-85S) and one wild variety (TVNu 72) under a range of temperatures: 19°C, 22°C, 25°C, 28°C, 31°C, 34°C, 37°C, 40°C and 43°C. IT84E-124 served as the susceptible and TVNu 72 as the resistant control for both insects. Development time of C. tomentosicollis ranged between 7 days at 37°C to 26 days at 19°C, and decreased with increasing temperature up to an upper temperature threshold of 37°C. The lower temperature threshold for development of C. tomentosicollis was estimated from regression curves to be ca 18.5°C, while the upper threshold was between 34°C and 37°C, the point where nymphal survivorship started to decline. Although 19°C and 22°C gave 90% and 80% survival, respectively, the duration of development at these temperatures was almost twice that reported under field conditions. Adult weights followed an inverse relationship with temperature. Third instar larvae of M. testulalis, obtained after rearing on artificial diet for 7 days prior to feeding on the plants, began to pupate 3 days after infestation at 28, 31 and 34°C. However, adults were obtained only at 22°C and 28°C. Temperatures above 34°C were lethal to the larvae which dried out prior to pupating. The lower temperature threshold determined by regression for pupae was 15.6°-17.8°C on both IT84E-124 and MRx 10-85S. Upper temperature threshold was estimated to be between 28 and 34°C at which no adult emergence was obtained. Female pupae were larger than males and temperature did not appear to influence sex ratio. Thermal requirements, expressed in degree days (DD), increased with temperature for C. tomentosicollis up to 31°C on all varieties. Degree days for M. testulalis pupae were of a lower magnitude than those computed for C. tomentosicollis. Zusammenfassung Entwicklungsprofile zweier Schädlinge an resistenten und empfindlichen Vigna-Genotypen bei konstanten Temperaturen Es wurden Wachstum und Entwicklung von Clavigralla tomentosicollis Stäl (Hem., Coreidae) und Maruca testulalis Geyer (Lep., Pyralidae) unter Laborbedingungen bei Verwendung von 3 kultivierten Vigna-Varietäten (IT84E-124, TVu 1890, MRx 10-85S) und einer Wildwuchs-Varietät (TVNu 72) bei konstanten Temperaturen von 19, 22, 25, 28, 31, 34, 37, 40 und 43°C untersucht. IT84E-124 diente als empfindliche und TVNu 72 als resistente Kontrolle für die beiden Insekten. Die Entwicklungszeit von C. tomentosicollis betrug zwischen 7 Tagen bei 37°C bis 26 Tagen bei 19°C und nahm mit ansteigender Temperatur ab bis zur oberen Temperaturgrenze von 37°C. Die untere Temperaturgrenze ergab sich aus den Regressionskurven zu 18,5°C, die obere lag zwischen 34 und 37°C. Bei letzterer Temperatur begann die Überlebensfähigkeit der Nymphen zu sinken. Obgleich bei 19 und 27°C die Überlebensquoten noch bei 90% und 80% lagen, war die Entwicklungsdauer bei diesen Temperaturen doppelt so lang wie unter Freilandverhältnissen. Die Gewichte der Adulten folgten einer inversen Beziehung zur Temperatur. Die Drittlarven von M. testulalis, die aus der Zucht mit künstlicher Diät 7 Tage früher als bei normaler Pflanzenernährung gewonnen wurden, begannen mit der Verpuppung 3 Tage nach Beeinflussung durch Temperaturen zwischen 28 und 34°C. Jedoch wurden Adulte nur aus Zuchten bei 22 und 28°C gewonnen. Temperaturen über 34°C waren für die Larven letal; diese starben vor der Verpuppung ab. Die untere Temperaturgrenze lag (It. Regressionskurven) zwischen 15,6 und 17,8°C bei beiden Varietäten IT84E-124 und MRx 10-85S. Die obere Temperaturgrenze wurde zwischen 28 und 34°C ermittelt. Die weiblichen Puppen waren größer als die männlichen. Die Temperatur beeinflußte das Geschlechterverhältnis nicht. Die Temperaturbedingungen, ausgedrückt in Tages-Graden (degree days DD) nahmen mit ansteigender Temperatur für C. tomentosicollis bis zu 31°C auf allen Varietäten zu. Die DD-Werte für M. testulalis-Puppen waren geringer als jene von C. tomentosicollis. [ABSTRACT FROM AUTHOR]