Though the replacement of European bees by Africanized honey bees in tropical America has attracted considerable attention, little is known about the temporal changes in morphological and genetic characteristics in these bee populations. We examined the changes in the morphometric and genetic profiles of an Africanized honey bee population collected near where the original African swarms escape...

Apis mellifera capensis is unique among honeybees in that unmated workers can produce pseudo-clonal female offspring via thelytokous parthenogenesis. Workers use this ability to compete among themselves and with their queen to be the mother of new queens. Males could therefore enhance their reproductive success by imprinting genes that enhance fertility in their daughter workers. This possibili...

Polymerase chain reaction(PCR)-ampliÞedmitochondrialDNA(mtDNA)assayshave been used in studies of the Africanization process in neotropical feral and managed honey bee populations. The approach has been adopted, in conjunction with morphometric analysis, to identify Africanized bees for regulatory purposes in the United States such as in California. In this study, 211 Old World colonies, represe...

A population ecological hostparasite model is used to evaluate the potential impact of clonal parasitic laying workers of the Cape honeybee, Apis mellifera capensis on populations of Apis mellifera scutellata host colonies in apiaries and in the wild. The model includes three basic life history parameters: reproductive rate of the host colonies, transmission efficiency of the parasite and the d...

Medicago truncatula is a model legume forage crop native to the arid and semi-arid environments of the Mediterranean. Given its drought-adapted nature, it is an ideal candidate to study the molecular and biochemical mechanisms conferring drought resistance in plants. Medicago plants were subjected to a progressive drought stress over 14 d of water withholding followed by rewatering under contro...

to study the effect of different fertilizing systems on macro and micro nutrients uptake by annual medic (medicago scutellata cv. robinson) an experiment was conducted under dry farming and irrigated conditions at two research stations (sararood dryland agricultural research institute and soil fertility research station in mahidasht) during 2009 growing season. the experimental treatments consi...

Thirty seven new Neotropical species of the phorid genus Neopleurophora are described— N. acrensis, sp. nov., N. acrochaetopyga,sp. nov., N. atlantica, sp. nov., N. balbii, sp. nov., N. boliviana, sp. nov., N. brachypyga, sp. nov., N.brachytarsus, sp. nov., N. browni, sp. nov., N. carcharopyga, sp. nov., N. cauca, sp. nov., N. ceratopyga, sp. nov., N. chocoensis, sp. nov., N. colobopyga, sp. no...

The study was conducted to determine the effects of nitrogen fertilizing systems and harvest frequency on levels of hard-seedness and hard-seed softening trend in M. scutellata var. Robinson. The study was carried out at Agricultural Research Farm of University of Tehran in Karaj during 2006. The experimental design was a randomized complete block with a split-split plot arrangement with four r...