Narrow Results

At present time, sustainable crop production is of prime importance due to the expansion of human population and diminishing cultivable land. Insects attack the plants’ roots, blooms and leaves and lessen the agricultural production across the globe. In this research work, we propose a nonlinear mathematical model to manage the spray of insecticides to control insect population and increase crop production. In the model formulation, we consider that the spraying of insecticides is attributed to both the density of insects and loss in crop production. This study identifies the range of spraying rate of insecticides at which the model system shows bistability behavior and its threshold value after which system stabilizes to the equilibrium with higher crop production. Further, we have also demonstrated that the model undergoes transcritical, saddle-node, Hopf, and Bogdanov–Takens bifurcations. The extensive numerical simulation is performed to validate the analytical findings.

In this research work, a nonlinear mathematical model is proposed and analyzed to study the adverse effects of insects on agricultural productivity by controlling the insect population using insecticides. In the model formulation, it is assumed that agricultural crops grow logistically and the growth rate of insects wholly depends on agricultural crops with Holling type-II functional response. It is further assumed that insects uptake insecticides; thus, the amount of insecticides decreases at a rate proportional to its amount and the density of insect population, and the growth rate of insect population decrease in the same proportion. The feasibility of all non-negative equilibria and their stability properties are discussed. Stability analysis specifies that agricultural crop consumption rate destabilizes the system; however, the spraying rate of insecticides stabilizes the system. The conditions for the existence of pitchfork and Hopf-bifurcation are derived. Considering the spraying rate of insecticides as time-dependent, we have also discussed the optimal control strategy to minimize both insect density and the associated cost. The numerical simulation validates the analytical findings.

‘Made in China 2025’ Momentum Propelling the Medical Device Industry Forward.

China to Build New Comprehensive National Labs.

NSFC - UNEP Project Launched to Boost Food and Water Security in Zambezi Basin.

New Tech Turns Potato Effluent into Fertilizer.

How Does Ruminal Protein and Feed Intake Effect on Endogenous Nitrogen and Amino Acids Flow in Goats?

China Plans More Gravitational Wave Research.

TUFM Links Mitochondrial Dysfunction to EMT in Lung Cancer.

How Organic Matter Decomposition Responds to Labile C and N Inputs.

Transgenic Monkeys Overexpressing Human MECP2 Gene Exhibit Autism-Like Behaviors and Germline Transmission.

Hearts of Cows Used in Ancient Cosmetics.

Genetic Lineage Tracing Analyses Reveal Endocardial Origin of Cardiac Fat.

Hong Kong News – Flu Remains the Most Prevalent Fatal Viruses in Hong Kong.

China boosts plans to motivate its scientists.

Chinese researcher recognized by World Food Prize.

Breakthrough new rice variety announced in Northern China.

Ebola vaccine approved in China.

Study reveals anti-cancer properties of a fungus used in traditional medicine.

CRISPR bacon: Chinese scientists create genetically modified low-fat pigs.

A new weapon of fighting Malaria.

Gene sequencing technology saw rapid growth in China.

Chinese scientists map genome sequences for Peony.

Werum IT Solutions and Neotrident sign partnership in China.

KOREA – Why are Korean eggs salmonella-free?

NETHERLANDS – Breaking bad: cancer cell drug addiction solved.

SINGAPORE – Singapore researchers create new ‘letters’ to enhance DNA functions.

SINGAPORE – Cancer scientists crack the durian genome.

SWEDEN – Study shows DuPont probiotics impact intestinal microbiota in colon cancer patients.

TAIWAN – New insights on breast cancer therapy.

USA – Genetically boosting the nutritional value of corn could benefit millions.

We report results of a “hindcast” experiment focusing on the agricultural and land-use component of the Global Change Assessment Model (GCAM). We initialize GCAM to reproduce observed agriculture and land use in 1990 and forecast agriculture and land use patterns on one-year time steps to 2010. We report overall model performance for nine crops in 14 regions. We report areas where the hindcast is in relatively good agreement with observations and areas where the correspondence is poorer. We find that when given observed crop yields as input data, producers in GCAM implicitly have perfect foresight for yields leading to over compensation for year-to-year yield variation. We explore a simple model in which planting decisions are based on expectations but production depends on actual yields and find that this addresses the implicit perfect foresight problem. Second, while existing policies are implicitly calibrated into IAMs, changes in those policies over the period of analysis can have a dramatic effect on the fidelity of model output. Third, we demonstrate that IAMs can employ techniques similar to those used by the climate modeling community to evaluate model skill. We find that hindcasting has the potential to yield substantial benefits to the IAM community.