Cherrybark oak (Quercrrs pagoda Raf.) seedlings were established and raised in the field under four light levels (100%. 53%. 27% or 8% of full sunlight) to study the effects of light availability on their shoot growth, biomass accumulation, and biomass distribution. After two growing seasons, greatest stem growth was observed on seedlings which received intermediate light levels, and this growt...

Knowledge on gene action and trait expression are important for effective breeding. The objective of this study was to determine the general combining ability (GCA), specific combining ability (SCA), maternal effects and heritability of drought tolerance, yield and yield components of candidate sweetpotato clones. Twelve genotypes selected for their high yield, dry matter content or drought tol...

BACKGROUND AND AIMS Biomass partitioning for resource conservation might affect plant allometry, accounting for a substantial amount of unexplained variation in existing plant allometry models. One means of resource conservation is through direct allocation to storage in particular organs. In this study, storage allocation and biomass allometry of deciduous and evergreen tree species from seaso...

The present article describes a field auger sampling method for row-crop root measurements. In agroecosystems where crops are planted in a specific design (row crops), sampling procedures for root biomass quantification need to consider the spatial variability of the root system. This article explains in detail how to sample and calculate root biomass considering the sampling position in the fi...

A pot experiment examined the biomass and As uptake of Medicago truncatula colonized by the arbuscular mycorrhizal (AM) fungus Glomus mosseae in low-P soil experimentally contaminated with different levels of arsenate. The biomass of G. mosseae external mycelium was unaffected by the highest addition level of As studied (200 mg kg(-1)) but shoot and root biomass declined in both mycorrhizal and...

Human selection for high crop yield under water-limited conditions should have led modern cereal cultivars to invest less in root biomass, be it unconsciously. To test this hypothesis we conducted a pot experiment with two spring wheat cultivars, one old and one modern, both widely grown in the semi-arid regions of China. Using the replacement series method introduced by de Wit, we showed that ...

Root systems serve important roles in carbon (C) storage and resource acquisition required for the increased photosynthesis expected in CO2-enriched atmospheres. For these reasons, understanding the changes in size, distribution and tissue chemistry of roots is central to predicting the ability of forests to capture anthropogenic CO2. We sampled 8000 cm(3) soil monoliths in a pine forest expose...

Stable carbon isotopes are used extensively to partition total soil CO2 efflux into root-derived rhizosphere respiration or autotrophic respiration and soil-derived heterotrophic respiration. However, it remains unclear whether CO2 from rhizosphere respiration has the same δC value as root biomass. Here we investigated the magnitude of C isotope fractionation during rhizosphere respiration rela...

the research was carried out to study the effect of provenance variation on stem length, stem biomass, root biomass and survival ofcaucasian oak (quercus macranthera) seedlings. the seeds were collected from several seed sources grown in an altitude range of 1800-2000 m a.s.l in alborz mountain, both from the northern facing slope, kordkoy and chichal, and from the southern facing slope, roudba...