1 We used a combination of laboratory and field experiments to test the hypothesis that the burial depth of Potamogeton pectinatus tubers will vary with local sediment type and swan predation pressure. 2 In the field, mortality due to predation by swans decreased linearly with burial depth (from 100% at the surface to 55% at 225 mm depth) and with sediment clay content. Average tuber size showe...

crop rotation is one of the essential practices in sustainable agricultural systems, be-cause of its effects on soil fertility and other benefits including a reduction in weed compe-tition. a field experiment was conducted at chaparsar rice research station, tonekabon, iran, from 2002 to 2003 to assess the influence of crop rotation, time of planting, and till-age depth on rice (oryza sativa l....

Information on the effect of planting date and irrigation on soybean [Glycine max (L.) Merr.] seed composition in the Early Soybean Production System (ESPS) is deficient, and what is available is inconclusive. The objective of this research was to investigate the effects of planting date on seed protein, oil, fatty acids, sugars, and minerals in soybean grown under irrigated (I) and non-irrigat...

During the 1991 and 1992 soybean growing seasons, field plots were established in South Carolina to study the effect of planting date on at-planting nematode densities and subsequent yield losses caused by Hoplolaimus columbus. The susceptible and intolerant soybean cv. Braxton was planted on five dates from to May to 28 June in 1991 and from 12 May to 28 June in 1992. Nematodes were recovered ...

For maize (Zea mays L.), early planting date could be of advantage to high yields but a review of planting date effect on high-yielding data is not yet available. Following this rationale, a synthesis-analysis was conducted from the farmer annual maize contest-winner data (n = 16171 data points; 2011-2016 period); cordially provided by the National Corn Growers Association and a scientific lite...

The Northeast China (NEC) was the most important agriculture areas and known as the Golden-Maize-Belt. Based on observed crop data and crop model, we design four simulating experiments and separate relative impacts and contribution under climate change, planting date shift, and varieties change as well change of varieties and planting date. Without planting date and varieties change, maize yiel...

Longleaf pine (Pinus palustris) seedlings were cultured with air lateral root pruning (side-vented containers, VT) or without (solid-walled containers, SW). Seedling root system morphology and growth were assessed before planting and 8 and 14 months after planting. Although VT seedlings had greater root collar diameter than the SW before planting, seedling height and ground line diameter were n...

Contents 1. Introduction 2. The unique character of forestry planting stock 2.1 Nursery-cultured planting stock 2.2 Wildings 3. The role of forest nurseries in forest management 4. Does the nursery affect the planting stock? 5. Types of nurseries 5.1 Bareroot nurseries 5.2 Container nurseries 5.3 A combination of container and bareroot nursery culture 6. Establishing a new nursery 6.1 Economic ...

This paper studies the no-bracket construction technology for reinforced concrete reinforcement, and uses planting-bar as support to solve problem that scaffolding cannot be erected due site factors. Firstly, steel bar pullout test was carried out study influence of strength, planting diameter, depth, structure type on force planting-bar. Secondly, finite element method used simulate selection ...