The N available after legumes is sufficient for maximum crop yields in many cropping systems. Fertilizing without accounting for the "extra" N mineralized from legume residues can contribute to high nitrate-N concentrations in the soil during crop production and increase nitrate-N leaching potential. Tillage practices also affect the physical, biological, and chemical nature of the soil, changi...

determining the best mixture of sorghum and fenugreek intercropping defines the best forage quality in medicinal forage production. this project was conducted to evaluate the effect of biological, chemical and integrated fertilizing systems on forage quantity and quality in sorghum and fenugreek intercropping. the experimental treatments were arranged as split plots based on randomized block de...

Many investigators maintain that spermatozoa that have initiated the acrosome reaction (AR) before reaching the surface of the egg's zona pellucida (ZP) are unable to bind and penetrate the ZP. A recent study has revealed that most fertilizing mouse spermatozoa initiate the AR before contacting the ZP. We found that acrosome-reacted spermatozoa collected from the perivitelline space of Cd9-null...

Hamster spermatozoa, collected from the caput and the cauda of the epididymis, are known to differ in their motility. They do not normally acquire fertilizing ability until they reach the proximal portion of the cauda epididymidis. The aim of the present investigation was to test the fertilizing capacity of spermatozoa from the caput epididymis after initiation. Sperm cells were incubated by ad...

Polyzoospermia is generally recognized as a male factor contributing to infertility and/or recurrent abortion. Although a reduced spermatozoal fertilizing capacity is assumed to be involved, so far there is no conclusive explanation for the assumed reduced reproductive performance in these patients, and data on the fertilizing capacity of spermatozoa from polyzoospermic men are lacking. The pre...

Mouse and hamster spermatozoa from the cauda epididymidis were deposited into the female tract at various periods following ligation of the corpus epididymidis. It was found that the number of spermatozoa in the cauda epididymidis decreased sooner in the hamster than in the mouse but the initial decrease in fertilizing ability occurred much earlier in the mouse than in the hamster. The fertiliz...

In Drosophila species of the obscura group, males exhibit sperm-heteromorphism, simultaneously producing both long sperm, capable of fertilization, and short sperm that are not. The production of multiple sperm types calls into question whether mating system correlates, such as sperm length and number trade-offs and female remating behavior, are the same as previously described in sperm-monomor...