A substantial increase in grain yield potential is required, along with better use of water and fertilizer, to ensure food security and environmental protection in future decades. For improvements in photosynthetic capacity to result in additional wheat yield, extra assimilates must be partitioned to developing spikes and grains and/or potential grain weight increased to accommodate the extra a...

Considering different fertility traits 411 cows from 73 farms used for economic analyses. From these, 202 lactating cows were selected for evaluating the fertility status. Pre-tested data sheets were used to record the socioeconomic status of the farms including their assets, cost and return and productive and reproductive performance of the dairy cows. Targets were set considering the situatio...

A national fertility evaluation was developed based on pregnancy rate, which measures the percentage of nonpregnant cows becoming pregnant within each 21-d opportunity period. Data for evaluation are days open, which are calculated as date pregnant minus previous calving date. Date pregnant is determined from last reported breeding or from subsequent calving minus expected gestation length. Suc...

Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis. Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human...

Female remating rate dictates the level of sperm competition in a population, and extensive research has focused on how sperm competition generates selection on male ejaculate allocation. Yet the way ejaculate allocation strategies in turn generate selection on female remating rates, which ultimately influence levels of sperm competition, has received much less consideration despite increasing ...

Although increasing evidences have emerged for responses of soil microorganisms to fertilizations, the knowledge regarding community assemblages that cause variations in composition is still lacking, as well as the possible feedback to soil fertility. Phylogenetic conservatism of species indicates their similar environmental preferences and/or function traits and phylogenetic signals further ca...

The male part of fertility traits in pigs has not often been analysed because of missing semen quality data in the case of natural mating. With increasing AI in pigs more data about semen quality of boars is available, so its influence on litter size can be analysed on bigger data sets. With advanced recording systems, single matings are recorded and important economic traits like mating succes...

We have identified, using composite interval mapping, quantitative trait loci (QTL) affecting a variety of life history traits (LHTs) in the nematode Caenorhabditis elegans. Using recombinant inbred strains assayed on the surface of agar plates, we found QTL for survival, early fertility, age of onset of sexual maturity, and population growth rate. There was no overall correlation between survi...

Ongoing ambitions are to understand the evolution of costly polyandry and its consequences for species ecology and evolution. Emerging patterns could stem from feed-back dynamics between the evolving mating system and its genetic environment, defined by interactions among kin including inbreeding. However, such feed-backs are rarely considered in nonselfing systems. We use a genetically explici...

The National Longitudinal Study of Adolescent Health data were used to test predictions from life history theory. We hypothesized that (1) in young adulthood an emerging life history strategy would exist as a common factor underlying many life history traits (e.g., health, relationship stability, economic success), (2) both environmental harshness and unpredictability would account for unique v...