Tis study examined the nest architecture, colony productivity, and duration of the immature stages of the social wasp Mischocyttarus consimilis Zikán (Hymenoptera: Vespidae). The study was carried out under field conditions. Nests of M. consimilis consist of a single uncovered comb, which is attached to the substratum by a single petiole. The data for the nest architecture showed a positive and...

Date palm plantlets derived from tissue culture suffer from slow rate of growth. Large sizes, of such plantlets, are also sold for higher price. Thus, producers and growers are demanding a method to stimulate the growth rate of these plantlets regenerated by tissue culture. In this study, gibberellic acid was applied alone at 100 ppm or informulations at 50 ppm. Phosphoric acid at 1%, v,v and u...

Hormonal and plant factors regulating the development of the inhibited cotyledonary buds of Lycopersicon esculentum Mill. cv. ;Fireball' seedlings were studied. Excision of the immature plumular leaves of 5- to 20- millimeter length significantly stimulated bud development after 2 to 4 days, but excision of leaves exceeding 20-millimeter length was without effect. Apical application of 20 micro...

miR408 is highly conserved among different plant species and targets transcripts encoding copper-binding proteins. The function of miR408 in reproductive development remains largely unclear despite it being known to play important roles during vegetative development in Arabidopsis. Here, we show that transgenic Arabidopsis plants overexpressing MIR408 have altered morphology including significa...

The current controversy about the "cohesion-tension" of water ascent in plants arises from the recent cryo-scanning electron microscopy (cryo-SEM) observations of xylem vessels content by Canny and coworkers (1995). On the basis of these observations it has been claimed that vessels were emptying and refilling during active transpiration in direct contradiction to the previous theory. In this s...

The photosynthetic assimilates in leaves of Perilla crispa attached to the plant were labeled by treating the leaves with (14)CO(2). When subsequently detached, these leaves exuded a negligible amount of radioactivity from the cut petiole into water. Ethylenediaminetetraacetate (EDTA), citric acid, and ethyleneglycol-bis (beta-aminoethyl ether) N,N'-tetraacetate greatly increased exudation of l...

Nitrogen fertilizer applications, for maximum fertilizer efficiencies and crop yields, should be based on the N required by the crop during its various growth stages. The objectives of this paper were to identify the N requirements of the potato plant (Solarium tuberosurn L.) during growth and to evaluate selected soil and plant tissue tests as indicators of the plant's N status. Growth analysi...

The ascorbate-glutathione (ASC-GSH) cycle has an important role in defensive processes against oxidative damage generated by drought stress. In this study, the changes that take place in apoplastic and symplastic ASC-GSH cycle enzymes of the leaf and petiole were investigated under drought stress causing leaf rolling in Ctenanthe setosa (Rose.) Eichler (Marantaceae). Apoplastic and symplastic e...