Latest in agriculture
The questions agriculture is arguing about now, explained from the evidence.
Antimicrobial resistance in livestock and One HealthHow antimicrobial resistance arises and spreads between animals, people and the environment, why livestock use matters, and what responsible use means.7 min read · current topicBiologicals: biostimulants and biopesticidesWhat agricultural biologicals are, how biopesticides, biostimulants and biofertilisers differ, how they are used and regulated, and what the evidence says.6 min read · current topicClimate-smart agricultureWhat climate-smart agriculture means, its three pillars, the practices behind it, how its results are measured, and the criticisms worth knowing.6 min read · current topicControlled-environment agriculture and vertical farmsGreenhouses, plant factories and vertical farms: how they work, what they grow well, the energy arithmetic of LED lighting, and why many have struggled.6 min read · current topicDigital agriculture: satellites, NDVI and decision toolsHow satellites see crops, what NDVI measures and how to calculate it, what digital tools can do for farmers, and the questions of data and access.6 min read · current topicDrones in agricultureWhat farm drones do today, from crop sensing to spraying and seeding, how to calculate spray rates and work rates, and the rules, risks and real limits.6 min read · current topicGene-edited crops and how the world regulates themWhat gene editing is, how it differs from older breeding and transgenic crops, the SDN categories, the first products, and how countries regulate them.7 min read · current topicMethane from rice and livestock, and how to cut itWhy farming is the largest human source of methane, how rice fields and ruminants make it, and the practices and additives that cut it, with numbers.7 min read · current topicRegenerative agriculture: what the term meansWhat regenerative agriculture means, its soil-health principles, what the evidence shows for soil carbon, yields and profits, and why definitions matter.6 min read · current topicSoil carbon credits and agricultural carbon marketsHow farmers are paid for storing carbon in soil, how a credit is measured and verified, a worked example, and the problems of additionality and permanence.7 min read · current topic
Soil science
How soil holds water and nutrients, and how to keep it productive.
Cation exchange capacity and base saturationWhy clay and humus hold nutrients, what CEC and base saturation mean, typical values, how they are measured, and how to calculate them.7 min readSaline, sodic and saline-sodic soils, and their reclamationHow salt and sodium damage soils and crops, how EC, ESP, SAR and pH classify them, and how to reclaim each kind, with gypsum and leaching worked out.8 min readSoil erosion and the Universal Soil Loss EquationHow water and wind erode soil, the stages from splash to gully, what each USLE factor means, and how to estimate soil loss and cut it.7 min readSoil pH, soil acidity and limingWhat soil pH measures, why soils turn acid, how pH controls nutrient availability and aluminium toxicity, and how to calculate a lime dose.7 min readSoil texture and the textural triangleWhat sand, silt and clay are, how they are measured, how to read the textural triangle, and why texture decides water, nutrients and tillage.8 min readThe essential plant nutrients and their deficiency symptomsThe 17 elements every plant needs, the rules that make an element essential, what each one does, and how to read deficiency symptoms.7 min readThe nitrogen cycle in agricultural soilsHow nitrogen moves from air to soil to crop and back: fixation, mineralisation, nitrification, uptake and the three ways a field loses it.8 min read
Agronomy and crop production
Growing field crops: systems, water, weeds and the history that shaped them.
Crop water requirement: ET₀, Kc and irrigation schedulingHow much water a crop uses and when to irrigate it: reference evapotranspiration, the crop coefficient curve, available soil water and worked calculations.7 min readIntercropping and the land equivalent ratioWhy growing two crops together can out-yield growing them apart, the main types of intercropping, and how to calculate and read the land equivalent ratio.7 min readThe Green Revolution: what it changed and what it costHow semi-dwarf wheat and rice, fertiliser and irrigation transformed cereal yields from the 1960s, where it worked, where it did not, and what it cost.7 min readWeed management and the critical period of crop–weed competitionHow weeds cut yields, what the critical period of weed competition is and how it is measured, and how to combine control methods.7 min read
Plant physiology and botany
How a plant captures light, grows, flowers and responds to stress.
C3, C4 and CAM photosynthesisThe three ways plants fix carbon dioxide, why Rubisco's weakness led to C4 and CAM, how they differ in water and nitrogen use, and which crops use which.7 min readPlant hormones and their uses in agricultureAuxins, gibberellins, cytokinins, abscisic acid, ethylene and the newer hormones: how each was discovered, what it does, and how growers use them.7 min read
Genetics and plant breeding
Inheritance, variation and how new varieties reach farmers.
Hardy–Weinberg equilibriumThe rule that links allele and genotype frequencies in a population, its assumptions, how to test it, and how breeders use it to estimate carriers.6 min readHeterosis, male sterility and hybrid seedWhy hybrids out-yield their parents, how heterosis is measured, and how male sterility and restorer genes make hybrid seed production possible.7 min readMendel's laws and the classic ratiosDominance, segregation and independent assortment with Mendel's peas: monohybrid, dihybrid and test crosses, the classic ratios, and the chi-square check.7 min readSeed classes and seed certificationHow a new variety's seed is multiplied through breeder, foundation and certified classes, what certification checks, and how seed quality is tested.7 min read
Plant pathology
Why crops get sick and how disease is managed.
Fungal, bacterial and viral plant diseases: telling them apartHow to tell fungal, bacterial, viral and other plant diseases apart from signs and symptoms, how Koch's postulates prove a cause, and why it matters.7 min readThe disease triangle and plant disease epidemiologyWhy plant disease needs host, pathogen and environment together, how epidemics build up, how to calculate the infection rate, and how control works.6 min read
Entomology and crop protection
Insects, pests and protecting a crop without wrecking the field's ecology.
Economic injury level and economic thresholdWhen a pest is worth controlling: the economic injury level and threshold, how to calculate them, how pests are classed, and how scouting uses them.6 min readIntegrated pest managementWhat integrated pest management is, why it replaced calendar spraying, its building blocks from prevention to pesticides, and how it works on a real farm.7 min read
Agricultural economics and marketing
Costs, prices, markets and the decisions behind them.
Marketing channels, price spread and marketing efficiencyHow farm produce reaches consumers, what intermediaries do, how to calculate price spread and producer's share, and how marketing efficiency is measured.6 min readPrice elasticity and the cobweb model of farm pricesWhy farm prices swing so much: price and income elasticity of food demand, the paradox of a good harvest, and the cobweb model of boom-and-bust cycles.6 min readThe law of diminishing returns and the production functionWhy each extra unit of fertiliser or labour adds less output, the three stages of production, and how to find the most profitable input level.6 min read
Extension and rural development
How knowledge travels to farms, and how farm communities organise.
Animal science and veterinary
Livestock nutrition, health and production.
Dairy and food science
Keeping food safe, and the science of processing it.
Thermal processing: D, z and F valuesHow heat kills microbes in canned and pasteurised foods, what D, z and F values mean, the botulinum cook, and how to calculate process lethality.7 min readWater activity and hurdle technologyWhy water activity, not moisture content, decides whether food spoils, the limits for bacteria, yeasts and moulds, and how hurdle technology works.7 min read
Forestry and agroforestry
Trees in forests and on farms.
Statistics and research methods
Designing experiments and reading the numbers honestly.
How these are written
Topics, never papers
Topics are chosen from the syllabi of more than five hundred agriculture and allied examinations worldwide. No past paper is copied; every example and number is our own.
For every country
No country is the default. Principles come first, then examples from the regions where each topic actually matters.
Sources you can check
Every article lists the textbooks, international standards and reviews it was written from.
A moderated discussion
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