From 1990 onwards, a new demand was imposed on Brazilian sugarcane farming: raw mechanical harvesting. This new practice drastically changed the production environment, adding a significant volume of organic material to the sugarcane plots.

Initially, the mechanization of harvesting and planting processes was very negative for agricultural productivity, increasing the risks to the economic sustainability of the sugarcane business. Discussions and exercises ensued trying to answer how to make planting and harvesting sugarcane fields viable. The first answer came with the conclusion: we need to increase the Ton of Sugarcane per Hectare of sugarcane fields.

In our analyses, we identified a significant reduction in sugarcane productivity (first cycle). Productivities of 125 tons per hectare in sugarcane at the time of manual planting were replaced by Tonne of Sugarcane per Hectare of 90 to 110 tons per hectare in general in areas of mechanized planting. This happened despite the efforts of the genetic improvement programs of Ridesa, the Sugarcane Technology Center and the Campinas Agronomic Institute, which presented new varietal options with greater biological potential for producers almost every year.

It was at that moment that we focused on this analysis to identify the causes of this low productivity and we established strategies to mitigate the harmful effects. Components of agricultural productivity: Sugarcane productivity is constructed from the components of Tonne of Sugarcane per Hectare and expressed in mass (tonnes of stalks). The Ton of Sugarcane per Hectare component can be estimated by the number of stalks per hectare multiplied by the average weight of the stalks.

What is “Three-Digit Cane”? These are the sugarcane plantations that reach productivity (Tons of Sugarcane per Hectare) greater than 100 tons per hectare on average of the first five cuts. Sugarcane productivity can be called “Biological Heritage”. How to build a high biological heritage? As there is a high correlation between the “stalk population” and the Tonne of Sugarcane per Hectare, we must give great emphasis when forming a new sugarcane field, choosing varieties that have a good stalk population as one of the main characteristics. These varieties must be planted in an area where all soil nutrition and plant protection practices must be practiced with excellence.

Therefore, we must obsessively seek excellence in planning and execution of planting. Therefore, among the steps towards transversal gains, we can mention the maintenance or even gains in the culm population throughout the cuts. The Third Axis Matrix strategy, which advocates bringing forward cuts in the newest cycles (first, second and third cuts), has greatly helped with this objective. Another relevant factor is the use of varieties that are well adapted to mechanical planting (we call them facilitating varieties) and that have the “ability” to produce good tillering. This invariably establishes populations above 75,000 stalks per hectare for almost all varieties.

There are, however, varieties that reach populations in sugarcane plants above 90,000 culms. The Campinas Agronomic Institute's Sugarcane Program has been working hard for 30 years to obtain varieties that have a high number of stalks. In the last seven years, the Agronomic Institute of Campinas launched two varieties that have this profile: IACCTC07-8008 and IACCTC07-7207. They reach populations of 110 to 130 thousand stalks per hectare. In commercial areas, they have achieved high productivity of 140 to 230 tons per hectare in the rainfed area.

Reducing the water deficit using the three-dimensional matrix (3rd axis): From 1997 onwards, the Sugarcane Program of the Campinas Agronomic Institute established an experimental network with the support of numerous companies in the form of a network, to evaluate genotypes from the final phase of the program of sugarcane genetic improvement at the Agronomic Institute of Campinas and, thus, identify new varieties for the companies' commercial area.

This network was established based on knowledge of soils/production environments and harvest season/third (first third, second third and 3rd third), which, under the conditions of the State of São Paulo, coincided with Autumn (1), Winter (2) and Spring (3). Therefore, we defined an environment matrix with two factors (Environment and Harvest Time) and three levels. This matrix, which we call Bi-dimensional, ended up being adopted by many producers who thus avoided coinciding the most restrictive edaphoclimatic environments (worse soils) with the time of lower water availability in the soil (in this case, in spring).

Based on the knowledge generated, Antônio Carlos M. de Vasconcelos, in his doctoral thesis (2002), in which he detailed the dynamics of the root system of a hybrid sugarcane cultivar, made it clear that the roots went deeper into the profile of the soil each year of cultivation and, therefore, older sugarcane fields had greater tolerance in relation to water deficit. Therefore, we felt the need to include a third factor in our Matrix, which was the sugarcane cycle, correlating older sugarcane fields with greater protection from water deficit for the plant under cultivation. We call this third factor the Third Axis, thus generating a Three-Dimensional Matrix (three factors with three levels). The application of the Third Axis concept in practice led to a mitigation of the water deficit.

The reduction of water deficit is related to agricultural productivity, and, therefore, we can consider that a reduction in water deficit of 100 millimeters throughout a sugarcane production cycle could result in increases in tons of stalks per hectare in the order of 8 to 13 tons per hectare, with the answer depending on the production environment and the biological potential of the cultivated variety.

Efforts in agronomic science are aimed at generating and transferring technologies that help agricultural crops make the best use of the water available in the soil and adapt to adverse conditions. In this scenario, in the sugar-energy sector, the Third Axis Matrix stands out, a water deficit mitigation model developed by the Agronomic Institute (Instituto Agronomic de Campinas and Agência Paulista de Tecnologia dos Agronegócios ), of the Secretariat of Agriculture and Supply of the State of São Paulo, which increases agro-industrial productivity by around 30%. This jump represents an increase of 23 tons per hectare, a yield that should soon lead to an increase of 46 million tons of sugarcane in the São Paulo sugarcane industry alone. The increase in the producer's income is 6 billion reais per year.

We therefore understand that, with these strategies, we can build high sugarcane productivity in its first cycle (sugarcane plant) and that mitigating the water deficit will result in less deconstruction of the ton of stalks per hectare throughout the cuts, allowing us to achieve triple-digit productivity over the first five cuts.