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Brazilian Animal-drawn NT planters

There are two basic designs of NT planters: the first evolved from the Gralha Azul/IAPAR prototype and the second evolved from the "fuçador" plow. The first design is represented by the models Mafrense, Iadel, and to some extent, Ryc, and the second by Werner, Triton (a copy of Werner) and Fitarelli. The latter are also regarded as Minimum-tillage planters.

Farmers from the Southweastern and Central-Southern region from the State of Paraná, Brazil, facilitated by IAPAR Farming Systems Research (FSR) group, have been doing some evaluations of these models. This evaluation is complemented by technical evaluations conducted jointly by IAPAR researchers and technicians, with extension agents. Summarized below are key points of the equipment:

• The planters that evolved from the "fuçador plow", particularly the Werner model, are the most suitable to African conditions (in my opinion), because they are lighter, simple in adjustments, less expensive. However, 1) the options of seed plates are very few, which can result in plant populations below or above the desired. 2) due to the hitching characteristics, the model for oxen (with longer shaft) is more efficient than the model for horses. 3) to have its efficiency improved, the model for horses must have a hitch point with different options so as to provide different levels of GC transfer to the coulter; a protection structure must be provided in order to avoid risk to the animal; the furrow opener is too wide, resulting in excessive soil disturbance at the furrow; 4) the size and shape of the hopper can be optimized in order to allow more autonomy and avoid seed losses at the bottom of the hopper. During our participatory evaluations, we assessed that the Werner model is preferred by farmers wich own oxen and cultivate in stony and hilly areas.

• The Triton model is a new option to Werner, and the manufacturer have done some of the adaptations suggested above: more seed plates options and a narrower furrow opener.

• The models evolved from Gralha Azul/IAPAR prototype are preferred by the farmers which own pairs of horses (like in Central-Southern region). The models with two land wheels are suited only to flat areas. The advantage of those equipment are: more options of seed plates; good penetration ability of the furrow opener (chisel types), particularly the Ryc and Iadel models. Furrow openers Disadvantages are: high cost; more complex in adjustments, heavier.

• Besides the one-row models, there are some manufacturers which produce multiple-rows planters: Fitarelli, Picetti and Mafrense.

Photos and information on the main models are presented below.