Understanding of the timing, orientation and transmission mode of crop disease spread is very important in prevention and treatment of crop diseases, especially for crossborder crop diseases. In this paper, we introduced the complex network approach to model trans-boundary spread of diseases. In the model, the process of crop disease spread is characterized as a network, where patches of crop p...

Ryegrass is the probably the most damaging weed to winter wheat over a large part of the high rainfall area in the central, north and east Texas. Economic losses in wheat occur through reduced grain yield, quality, foreign matter, and harvest efficiency. Yield loss can exceed 90% in heavy infestations. In addition to yield reduction, reduced harvest efficiency results in lower test weight, high...

We introduce a theoretical framework that predicts the optimum planting density and maximal yield for an annual crop plant. Two critical parameters determine the trajectory of plant growth and the optimal density, N(opt), where canopies of growing plants just come into contact, and competition: (i) maximal size at maturity, M(max), which differs among varieties due to artificial selection for d...

This work presents a mathematical model adapted from literature for the Crop Rotation Problem with Demand Constraints (CRP-D). This highly complex combinatorial problem is devised to find a vegetable planting program that takes into account green fertilization restrictions, the set-aside period, planting restrictions for neighboring lots and for crop sequencing, demand constraints, while, at th...

Crop planting suitability evaluation is important for agricultural production. In this study, a comprehensive evaluation framework which combined geographical information system, remote sensing, global position system and geostatistics with other models was presented to evaluate the tobacco planting suitability on a small scale. Ten indicators from three respects of climate, terrain and soil nu...

Insecticides used at planting, either in-furrow or as seed treatments, are the recommended management option for control of thrips in cotton in Arkansas (Greene, 00 ). However, in recent years the efficacy of standards, such as aldicarb in-furrow, has decreased. This has resulted in added cost of control due to foliar insecticide applications being required in addition to the at-planting insect...

Winter wheat is one kind of important crop in China. It’s planting area is one key element to explain yield change. To obtain winter wheat planting area as soon as possible can provide scientific reference for our country’s making related policy. Basing on the cropping system in Shandong province, winter wheat is divided into two kinds “winter wheat sowed by machine-maize” and “people broadcast...

Establishing rhizoma peanut (Arachis glabrata Benth.; rp) in strips into existing bahiagrass (Paspalum notatum Flüggé) pastures has potential to increase forage nutritive value, decrease N fertilizer use, and improve N cycling. Grazing the grass–legume mixture in the year after planting may be possible, but appropriate grazing management strategies have not been defined. The objectives were to ...