hii Publication haipo kwenye lugha yako, kuangalia kwa: English (en), Français (fr), Español (es),
au tumia ufasiri wa google:  

ECHO Tech Notes are subject-specific publications about topics important to those working in the tropics and subtropics. Our material is authored by ECHO staff and outside writers, all with experience and knowledge of their subject. These documents are free for your use and will hopefully serve a valuable role in your working library of resources in agricultural development!

95 Matoleo katika Chapisho hili (Inaonyesha masuala 57 - 48) |

TN #57 An Introduction To Soil Fertility - 20-01-2009

All plants need certain mineral elements for proper growth, development, and maintenance. The basic structure of all organisms is built of carbon (C), oxygen (O) and hydrogen (H). Plants obtain these elements from water (H2O) in the soil and carbon dioxide (CO2) in the air, so no input is required beyond being sure the plant has an adequate water supply to meet its needs. Turning the H2O and CO2 into organic building blocks, however, is a complex process that requires the assistance of at least 13 other elements.

Three elements, nitrogen (N), phosphorus (P), and potassium (K), are required in relatively large quantities and are referred to as primary or macronutrients. N is an important component of all protein, so is integral to the plant structure. P is a minor component of protein, but is integral to the molecules that control energy flow within the plant and is a component of genetic material. The role of K seems to be in maintaining the correct salt concentration in the plant sap. N, P, and K, in varying ratios, are the primary constituents of all chemical fertilizers. Depending on the fertilizer origin, their amounts present may be expressed as N, P2O5, and K2O.

What's inside:

  • Introduction
  • How do I tell whether the soil contains what a plant needs?
  • What deficiency symptoms should I be looking for?
  • How do I assure that nutrient supplies in soil are maintained?
  • Relationship of cropping systems and soil fertility
  • Bibliography


Cite this article as:

Harter, R.D. 2009. An Introduction To Soil Fertility. ECHO Technical Note no. 57.

TN #56 Lagos Spinach - 01-01-2007

In a world where hunger and poverty are issues with a large percentage of the population, technology and education are wanting, and agricultural resources are often scarce, a farmer is thankful for low-maintenance crops that will grow with a minimal input of effort and resources. Lagos spinach (Celosia argentea) is such a crop. A little-known, underexploited leafy vegetable, C. argentea is a crop that is easy to plant, grows in most climates and soils, withstands drought and heat, has few problems with pests and disease, is easy to prepare, highly nutritious and tastes good, and produces large quantities of seed. One might wonder why such a plant is so little known!

Cite this article as:

Yarger, L. 2007. Lagos Spinach. ECHO Technical Note no. 56.

TN #55 A-Frame Level - 01-01-2006

The A-Frame Level is a simple, yet accurate tool used for constructing contours on a hillside or slope. It is useful in the basic construction of hillside farming systems, such as the SALT systems, as well as for establishing level contours and drainage ditches. Level contours on a slope reduce erosion, increase water infiltration, protect slopes and facilitate reclamation of degraded hillsides. The A-Frame Level can also be used to determine the percent slope of a hillside. This document provides the basic instructions for constructing and using an A-Frame Level.

What’s Inside:

  • Materials for Construction
  • Assembly of A-Frame
  • Calibration of A-Frame
  • Marking Contour Lines
  • Measuring a Slope
  • Useful Resources 

Cite this article as:

Yarger, L. and B. Doerr 2006. A-Frame Level. ECHO Technical Note no. 55.

TN #54 Preparing for Agricultural Missions - 01-04-2006

There are two parts to this document; part 1 provides a brief description of the things a college student should consider as he/she chooses opportunities for learning and part 2 lists organizations that provide some practical training. The second section will be most useful for individuals applying to or who have been accepted by a mission and are preparing for service, and for missionaries that have limited knowledge of agriculture, health care, and appropriate technology yet realize their ministry has some level of involvement in one or more of these areas.

Cite this article as:

Price, M.L., S.D. Sherman, and L. Yarger 2006. Preparing for Agricultural Missions. ECHO Technical Note no. 54.

TN #53 Chaya - 01-01-2006

Dr. Martin Price, co-founder of ECHO and former head of ECHO’s Agricultural Resources Department, has said, “I would consider chaya to be one of the five most important underutilized food plants ECHO distributes. I give it this rank because of its ability to thrive in both arid and rainy regions, its little need for care or extra fertility, its lack of insect or disease pests, its high production per square foot, and the exceptional nutritional value of its cooked leaves.”

Frank Martin, Ruth Ruberté, and Laura Meitzner agreed; in their book Edible Leaves of the Tropics, they wrote, “As a year-round source of high-quality food in a wide range of conditions, it is one of the most important edible-leaved plants for the tropics.”

And in an article in Economic Botany 56(4), “The Ethnobotany of Chaya,” Jeffrey Ross-Ibarra and Alvaro Molina-Cruz concluded, “Its high nutritive value, ease of propagation, productivity, tolerance of poor growth conditions, and resistance to pests and disease all make chaya a valuable potential crop that could benefit peoples of many different regions.”

Cite this article as:

Berkelaar, D. 2006. Chaya. ECHO Technical Note no. 53.

TN #52 Moringa Water Treatment - 01-03-2005

In addition to food, shelter and clothing, water is one of our basic human needs and lack of potable water is a major cause of death and disease in our world. The purpose of this document is to provide information on household water treatment using seeds of the Moringa oleifera tree.

Using natural materials to clarify water is a technique that has been practiced for centuries and of all the materials that have been used, seeds of the Moringa have been found to be one of the most effective.

Cite this article as:

Doerr, B. 2005. Moringa Water Treatment. ECHO Technical Note no. 52.

TN #51 Moringa Leaf Powder - 20-01-2005

The leaves of the Moringa oleifera tree are very nutritious. They can be consumed fresh, cooked or dried. Since dried Moringa leaves retain their nutrient content, it is possible to convert them into leaf powder. When there is an abundance of leaves, this leaf powder can be made and stored easily. Moringa Leaf Powder is an excellent nutritional supplement and can be added to any dish.

Cite this article as:

Doerr, B. and L. Cameron 2005. Moringa Leaf Powder. ECHO Technical Note no. 51.

TN #50 Statistical Analysis of Simple Agricultural Experiments - 01-04-2003

Use of a new crop variety or production technique may dramatically increase food production in a given area. Alternatively, an innovation successful in North America may utterly fail in the tropics. The goal of “adaptive research” is to evaluate a particular innovation for its usefulness under local conditions. This technical note is written for those who want to improve the quality of their experiments but who have little or no background in statistics. It supplements the 81st issue of ECHO Development Notes with step-by-step instructions on how to manually calculate statistics for the most commonly used experimental designs. A little persistence, very basic math skills, and perhaps a calculator are all you need to do the calculations. If you have a computer equipped with statistical software, doing a set of calculations by hand or with a calculator will help you to understand how to use the software and interpret the output. Examples are given for experiments in which only one factor (e.g. crop variety) is tested. A limited amount of statistical terminology is woven into the text for the benefit of those interested in further study.

Cite this article as:

Motis, T. 2003. Statistical Analysis of Simple Agricultural Experiments. ECHO Technical Note no. 50.

TN #49 Rope Maker - 01-01-2003

Rope can be made from cord or string or even discarded plastic bags using a simple spindle to twist the materials together. 

Cite this article as:

Forst, C. and L. Stoll 2003. Rope Maker. ECHO Technical Note no. 49.

TN #48 Acid Soils of the Tropics - 01-01-2002

Acidification of soil is a natural process with major ramifications on plant growth. As soils become more acid, particularly when the pH drops below 4.5, it becomes increasingly difficult to produce food crops. As soil pH declines, the supply of most plant nutrients decreases while aluminum and a few micronutrients become more soluble and toxic to plants. These problems are particularly acute in humid tropical regions that have been highly weathered. According to Sanchez and Logan (1992), for example, one third of the tropics, or 1.7 billion hectares, is acid enough for soluble aluminum to be toxic for most crop plants. We will look at some of the causes of acidification and list some of the expected results of both acidification and the practice of liming for acid neutralization.

What’s Inside:

  • What Causes Soil to Become Acid?
  • Soil pH and Aluminum
  • Effects of Acidification
  • Solution to the Problem
  • What Happens When Soil is Limed
  • Dangers of Over-Liming the Soil

Cite this article as:

Harter, R.D. 2002. Acid Soils of the Tropics. ECHO Technical Note no. 48.