Reproductive allocation is critically important for population maintenance and usually varies with not only environmental factors but also biotic ones. As a typical rhizome clonal plant in China's northern grasslands, Leymus chinensis usually dominates the steppe communities and grows in clonal patches. In order to clarify the sexual reproductive allocation of L. chinensis in the process of the...

Experiment was conducted as split plot in a randomized complete block design with three replications in Kermanshah to shed lights on economic analysis of deficit irrigation and integrated application of biological and chemical fertilizer son cultivation of medicinal plant Borage (Borago officinalis L). Irrigation tritments include: a) 30% less water than crop requires invegetative, b) inreprodu...

BACKGROUND AND AIMS Stinging nettle (Urtica dioica) is a herbaceous, dioecious perennial that is widely distributed around the world, reproduces both sexually and asexually, and is characterized by rapid growth. This work was aimed at evaluating the effects of plant maturity, shoot reproduction and sex on the growth of leaves and shoots. METHODS Growth rates of apical shoots, together with fo...

1. Trade-offs between reproduction and growth are central assumptions of life-history theory, but their implications for sexual size dimorphism (SSD) are poorly understood. 2. Adult male Yarrow's spiny lizards Sceloporus jarrovii average 10% larger than adult females. In a low-altitude (1700 m) population, this SSD develops because males grow more quickly than females during the first year of l...

Appropriate nutrient response is essential for growth and reproduction. Under favorable nutrient conditions, the C. elegans nuclear receptor DAF-12 is activated by dafachronic acids, hormones that commit larvae to reproductive growth. Here, we report that in addition to its well-studied role in controlling developmental gene expression, the DAF-12 endocrine system governs expression of a gene n...

The age-specific growth function of an observed population and the reproductive value function based on the population’s current vital rates determine the intrinsic rate of growth implied by those vital rates through the simple relationship given in equation (1). That equation establishes the analytical significance of age-specific growth, and leads to relationships that quantify a population’s...

Reproductive and growth data were obtained on 779 and 564 yearling beef heifers and bulls, respectively, that had sires with yearling scrotal circumference data at the San Juan Basin Research Center, Hesperus, CO. Partial regression coefficients of reproductive and growth traits on inbreeding (FXC) and age of the individual and adjusted scrotal circumference of sire (SCSI) were obtained. Growth...

The avianuncoupling protein (avUCP) is a member of the mitochondrial transporter superfamily that uncouples proton entry in the mitochondrial matrix from ATP synthesis. The polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method was used to estimate the allele and genotype frequencies of the UCP/HhaI polymorphisms and to determine associations between these polymorp...

A critical step in understanding the evolution and maintenance of alternative reproductive tactics is to obtain accurate comparisons of their fitness and to determine factors influencing individual status. In this study, we first used individual multilocus genotypic information to compare reproductive success between two alternative reproductive tactics of anadromous Atlantic salmon (Salmo sala...

reproductive efficiency in dairy cattle has been decreased over the last 5 decades despite significant gains in genetic selection, improved reproductive technologies and nutritional care. in high-yielding dairy cattle, the negative energy balance (neb) during the first week post-partum adversely affects ovarian activity, mainly follicle growth and steroidogenesis. circulating levels of non-este...