Somaclonal variation has been observed in many plant species and is an alternative way to create variants and expand the germplasm pool. A large scale tissue culture experiment was conducted with St. Augustinegrass, an important turfgrass species for the southern USA, to induce somaclonal variation to enlarge the germplasm pool for breeding efforts. Using an improved protocol, approximately 790...

In order to evaluate twelve doubled haploids (DHs) of Theobroma cacao L. used as parents, a trial was set up in Côte d'Ivoire. Several traits were observed, such as yield, vigour, yield/vigour ratios, resistance to the black pod disease caused by Phytophthora, percentage of flat beans and mean weight of 100 cocoa beans. Out of the three progenies derived from crosses between two DHs, two showed...

Seeds of carrot, groundnut, lettuce, oilseed rape and onion were stored hermetically in laminated aluminium foil packets in four environments (dry or ultra-dry moisture contents combined factorially with temperatures of 20°C or -20°C), replicated at several sites. After ten years’ hermetic storage, seed moisture content, equilibrium relative humidity, viability (assessed by ability to germinate...

Within the Job Demands-Resources model, the presence of job demands (e.g., work pressure) and the absence of job resources (e.g., social support) relate to burnout through a psychological energetic process, whereas the presence of job resources associates with work engagement through a motivational process. Although various mechanisms have been suggested to understand these processes, empirical...

Hydraulic impairment due to xylem embolism and carbon starvation are the two proposed mechanisms explaining drought-induced forest dieback and tree death. Here, we evaluate the relative role played by these two mechanisms in the long-term by quantifying wood-anatomical traits (tracheid size and area of parenchyma rays) and estimating the intrinsic water-use efficiency (iWUE) from carbon isotopi...

Timely harvest is critical to achieve maximum seed viability and vigour in agricultural production. However, little information exists concerning how to reap the best quality seeds of Leymus chinensis, which is the dominant and most promising grass species in the Songnen Grassland of Northern China. The objective of this study was to investigate and evaluate possible quality indices of the seed...

Understanding how genetic variation at individual loci contributes to adaptation of populations to different local environments is an important topic in modern evolutionary biology. To date, most evidence has pointed to conditionally neutral quantitative trait loci (QTL) showing fitness effects only in some environments, while there has been less evidence for single-locus fitness trade-offs. At...

Seeds are important to agriculture and conservation of plant biodiversity. In agriculture, seed germination performance is an important determinant of crop yield, in particular under adverse climatic conditions. Deterioration in seed quality is associated with the accumulation of cellular damage to macromolecules including lipids, protein, and DNA. Mechanisms that mitigate the deleterious cellu...

OBJECTIVE To determine whether doses of the pineal hormone melatonin alleviate jet lag. DESIGN Double blind, placebo controlled crossover trial. SETTING Long haul return flights from Auckland, New Zealand, to London and back. SUBJECTS Twenty volunteers with experience of transcontinental flights (eight women and 12 men aged 28 to 68). INTERVENTIONS Melatonin (or placebo) 5 mg three days...