Home  About us  Contact
 

Hypogaea L. (hypogaea + l)

Distribution by Scientific Domains
Life Sciences60%

Kinds of Hypogaea L.

  • arachis hypogaea l.
    		•

    Selected Abstracts

    The impact of a parasitic nematode, Thripinema fuscum, on the feeding behavior and vector competence of Frankliniella fusca

    ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2009
    Kelly R. Sims
    Abstract Frankliniella fusca (Hinds) (Thysanoptera: Thripidae) is the predominant thrips species found inhabiting and reproducing in peanut, Arachis hypogaea L. (Fabaceae), and is one of at least seven thrips species reported to transmit Tomato spotted wilt virus (TSWV). The entomogenous nematode Thripinema fuscum Tipping & Nguyen (Tylenchida: Allantonematidae), a natural enemy of F. fusca, parasitizes larval and adult populations under field conditions. All known Thripinema species render the host female thrips sterile and have the potential to suppress pest populations to near extinction. As a result, secondary spread of TSWV in peanut is reduced. Reduction of the virus under field conditions may also be due to lower transmission rates caused by parasite-induced alterations in host feeding behavior. Therefore, the feeding rates of healthy and parasitized F. fusca male and female cohorts on leaf discs were recorded daily for 10 days and digital images were subjected to image analysis and viral transmission rates were compared daily using double antibody sandwich enzyme-linked immunosorbent assay. Thripinema fuscum reduced the feeding of female F. fusca by nearly 65%, and the ability of females to transmit TSWV by 50%. Potential mechanisms underlying the parasite-induced alterations in feeding behavior and transmission are discussed. Parasitism by T. fuscum significantly reduced male longevity, but female longevity was not affected. These results provide further evidence that T. fuscum aids in regulating viruliferous F. fusca pest populations and suggests its potential as a biological control agent for inoculative release in peanut. [source]

    Influence of Soil Temperature on Seedling Emergence and Early Growth of Peanut Cultivars in Field Conditions

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2006
    P. V. V. Prasad
    Abstract Peanut or groundnut (Arachis hypogaea L.) sown in early spring often has poor seed germination and seedling development. The influence of soil temperature on seedling emergence and early growth of six peanut cultivars (Florida MDR98, Southern Runner, Georgia Green, SunOleic 97R, Florunner and C-99R) was studied in natural field soil profiles in temperature-gradient greenhouses. We evaluated the influence of a range of soil temperatures by sowing at eight dates between January 2001 and May 2002 in Gainesville, Florida. On each sowing date, two additional temperature treatments (ambient and ambient +4.5 °C air temperature) were evaluated by sowing on either end of each greenhouse and applying differential heating. In total, 16 different soil temperature treatments were evaluated. Each treatment was replicated four times in four different greenhouses. Mean soil temperature from sowing to final emergence in different treatments ranged from 15 to 32 °C. Sowing date, temperature treatment and cultivar had significant effect on seedling emergence and development (V2 stage). For all cultivars, the lowest germination was observed at the earliest sowing date (coolest soil temperature). Among cultivars, Florida MDR98 was the most sensitive to reduced (cool) temperature with the lowest germination and smallest seedling size at 21 days after sowing, followed by Southern Runner. Georgia Green was the most cold-tolerant with the highest germination, followed by SunOleic 97R. There were no significant differences among cultivars for base temperature, which averaged 11.7 and 9.8 °C for rate of emergence and rate of development to V2 stage respectively. These results imply that cultivar choice and/or genetic improvement of peanut for cold tolerance during emergence and seedling development in regions where cooler soil temperatures persist and/or regions where early sowing is desirable. [source]

    A MODEL FOR TEMPERATURE AND MOISTURE DISTRIBUTION DURING CONTINUOUS MICROWAVE DRYING,

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2005
    D. BOLDOR
    ABSTRACT A heat and mass transfer model of continuous drying of farmer stock (in-shell, uncured) peanuts (Arachis hypogaea L.) in a planar microwave applicator was developed and investigated. Transport phenomena equations previously developed for batch-type microwave drying were successfully adapted to account for the spatial variation of the electric field inside the applicator. The theoretical equations developed, together with experimental methods, were used to determine the effect of microwave power level and dielectric properties on the temperature profiles and reduction in peanuts' moisture content (mc). The temperature profiles from the solution of these equations matched the experimental ones determined using fiber optic temperature probes inserted into drying peanut pods. An exact theoretical determination of mc reduction during microwave drying was not possible due to the dependence of dielectric properties on mc. The surface temperature distribution of the peanut bed measured using infrared pyrometry was well correlated with internal temperature profiles. [source]

    Induction of Systemic Acquired Resistance in Arachis hypogaea L. by Sclerotium rolfsii Derived Elicitors

    JOURNAL OF PHYTOPATHOLOGY, Issue 9 2010
    Durgesh Nandini
    Abstract Plants evolve a strategy to survive the attacks of potential pathogens by inducing the microbial signal molecules. In this study, plant defence responses were induced in four different varieties of Arachis hypogaea (J-11, GG-20, TG-26 and TPG41) using the fungal components of Sclerotium rolfsii in the form of fungal culture filtrate (FCF) and mycelial cell wall (MCW), and the levels of defence-related signal molecule salicylic acid (SA), marker enzymes such as peroxidase (POX), phenylalanine ammonia lyase (PAL), ,-1,3-glucanase and lignin were determined. There was a substantial fold increase in POX, PAL, SA, ,-1,3-glucanase and lignin content in FCF- and MCW-treated plants of all varieties of groundnut when compared to that of control plants. The enzyme activities were much higher in FCF-treated plants than in MCW-treated plants. The increase in fold activity of enzymes and signal molecule varied between different varieties. These results indicate that the use of fungal components (FCF and MCW) had successfully induced systemic resistance in the four different varieties of groundnut plants against Sclerotium rolfsii. [source]

    Molecular diversity and association of SSR markers to rust and late leaf spot resistance in cultivated groundnut (Arachis hypogaea L.)

    PLANT BREEDING, Issue 1 2010
    S. Mondal
    With 1 figure and 2 tables Abstract Molecular diversity and association of simple sequence repeat (SSR) markers with rust and late leaf spot (LLS) resistance were detected in a set of 20 cultivated groundnut genotypes differing in resistance against both diseases. Out of 136 bands amplified from 26 primers, 104 were found polymorphic (76.5%). Cluster analysis (UPGMA) revealed two main clusters separated at 52% Jaccard's similarity coefficient according to disease reaction to rust and LLS. Based on the Kruskal,Wallis one-way anova and simple regression analysis three and four SSR alleles were found associated with rust and LLS resistance, respectively. [source]