Artificial regeneration of oak has been generally unsuccessful in maintaining the oak component in productive upland forests of eastern North America. We tested visual grading effects on quality-grown northern red oak (Quercus rubra) seedlings planted in two submesic stands on the Cumberland Plateau escarpment of Tennessee, USA. Seedlings were grown for one year using advanced fertilization and...

Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] plug seedlings were stored at 15°C in the light at a photosynthetic photon flux density of 15 µmol·m(-2)·s(-1) or in darkness for 6 days, to evaluate their chloroplast ultrastructure, and associated photosynthetic characteristics. Storage in the dark caused swelling, disordered granal arrangement, and starch grain disappearance in the ch...

The growth of outplanted high-quality 1-0 northern red oak (Quercus rubra L.) seedlings, growth differences between two categories of visually graded seedlings and herbivory by white-tail deer (Odocoileus virginianus (Boddaert)) were examined after two growing seasons. Seedlings were planted in plots receiving three overstory treatments (high grade, commercial clearcut, and two age) and an uncu...

Ozone exposure decreases belowground carbon allocation and root growth of plants; however, the extent to which these effects persist and the cumulative impact of ozone stress on plant growth are poorly understood. To evaluate the potential for plant compensation, we followed the progression of ozone effects, with particular emphasis on the development of new roots. Ponderosa pine (Pinus pondero...

We compared responses of cuttings and seedlings of Eucalyptus globulus Labill. subsp. globulus to water stress in a 9-week greenhouse experiment. Optimal water availability was achieved by watering pots daily to field capacity, and two water stress treatments were imposed by reducing watering frequency to every 6 or 14 days. Within each treatment, height growth rates of cuttings and seedlings w...

Respiratory activities were compared among rice seedlings germinated in air for 6 days (aerobic seedlings), those germinated under water for 5 days (submerged seedlings), and those grown in air for 1 day after 5 days' submerged germination (air-adapted seedlings). The respiratory activity of the submerged seedlings increased rapidly on transfer to air and reached a plateau at 16 hours in air. R...

Elaeagnus angustifolia L. is a drought-resistant species. Arbuscular mycorrhizal symbiosis is considered to be a bio-ameliorator of saline soils that can improve salinity tolerance in plants. The present study investigated the effects of inoculation with the arbuscular mycorrhizal fungus Rhizophagus irregularis on the biomass, antioxidant enzyme activities, and root, stem, and leaf ion accumula...

Three studies in the Coastal Plain of Georgia were remeasured 7 or 8 years after planting to determine the effects of planting depth on field performance of open-rooted seedlings [root-collar diameter (RCD) ≥ 5 mm]. Average planting depth (i.e. shoot height before planting minus shoot height above ground after planting) for machine planted P. elliottii was 14 cm while hand-planted P. taeda seed...

The objectives of this research are to develop the grafting robots and an acclimatization chamber for watermelon, and tomato seedlings. For watermelon seedlings, a top plug-in robotic grafting system has been developed, which is applicable for grafting a scion into a mature rootstock before the scion’s cotyledons spread. It thus makes the scion to be very tender and greatly different from the r...

A choice test revealed that Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), adults deposited approximately 3 times more eggs on wheat (Triticum spp.), seedlings than on barley (Hordeum spp.) or rice, Oryza sativa L., seedlings. On a barley seedling, 49.4% of eggs were deposited on either the abaxial leaf surface or the coleoptile and first leaf sheath (C&FLS), where newly hatc...