Multiple Forms of Acid Phosphatase in Cotyledons of Vigna mungo Seedlings

Acid phosphatase from cotyledons of dark-grown Vigna mungo seedlingswas separated into four forms (la, Ib, Ha and lib) by ion-exchangercolumn chromatographies. Each form of the acid phosphatase wascharacterized for its pH dependency, substrate specificity,thermal stability, activation energy, approximate molecularweight, and the effect of metal ions and other substances onits activity. Each form of the enzyme exhibited high activitytowards ATP and ADP relative to their activity towards p-nitrophenylphosphate,but showed very low activity towards phytate, a major organicphosphate reserve in cotyledons. Among the four forms, lib wasmost distinguishable by its low molecular weight and the thermalenhancement of activity.     

Presence of the water lily,Trapa natans L., increases fitness of the water strider,Gerris nepalensis

Abstract Exposure of the waterstrider, Gerris nepalensis, to leaves of the water lily, Trapa natans, during either the larval or adult stage increases the proportion of reproductive females (60.0%) and increases the number of eggs laid by G. nepalensis (25.1 ± 8.1) compared with leaves of another floating plant, Hydrocharis dubia (20.2%, 6.7 ± 17.8), and mimic leaves made of polystyrene (24.2%, 20.0 ± 16.9). The larval period at 25 °C is significantly shorter when larvae are reared together with water lily leaves than when reared with mimic leaves made of thin styrene. A significantly higher percentage (76.4 ± 39.9) of eggs laid by females that are reared with lily leaves in larval and adult stages develop successfully to the first instar compared with those reared with ‘mimic‐leaves’ (% hatched‐out successfully: 53.9 ± 39.3). The effect of T. natans on G. nepalensis demonstrated in the present study is to increase the number of G. nepalensis in the habitat and likely increase foraging pressure on the lily leaf beetle, Galerucella nipponensis. Possible mechanisms of this relationship between T. natans and G. nepalensis are discussed.