CIGR - International Conference of Agricultural Engineering XXXVII Congresso Brasileiro de Engenharia Agrícola

Brazil, August 31 to September 4, 2008

CORN SEEDING CHARACTERISTICS IN THE EEA PERGAMINO INFLUENCE AREA, BS. AS., .

ÁNGEL ROMITO 1, MARCOS ROBA 2, JUAN D’AMICO 1, LIDIA DONATO 1, NÉSTOR GONZÁLEZ 1, JAVIER ELISEI 1, DIEGO PAREDES 1, OMAR TESOURO 1.

1 Researcher, IIR, CNIA, INTA – , Argentina. e-mail: [email protected] 2 Undergraduate student, FAUBA / – Argentina.

Presented at CIGR INTERNATIONAL CONFERENCE OF AGRICULTURAL ENGINEERING XXXVII CONGRESSO BRASILEIRO DE ENGENHARIA AGRÍCOLA – CONBEA 2008 Brazil, August 31 to September 4, 2008

ABSTRACT: In agricultural production, the crop seeding is a task of paramount importance since it has a direct impact on the stand of plants to harvest and determines largely the performance that they will have throughout the ccycle. To exploit the full potential offered by inputs technology is necessary to know the scope and the actual conditions in which this task is performed. The objective of this study is to obtain information enabling a reliable characterization of the conditions of seeding and the efficiency achieved. For that purpose there was conducted a survey, collecting information on equipment, supplies, operating conditions and regulations made. Subsequently a field sampling was carried out, to characterize specific parameters of seeding. This paper presents the results of the study in 24 establishments located in the northern Buenos Aires , at the localities of Pergamino and Rojas (Argentina). From them arise that some of the characteristics of the planters, such as age and system of fertilization, as well as working velocity, determines the results of the seeding influencing the quality of implantation obtained. KEYWORDS: seeding, corn, seeders, case study, quality of implantation

INTRODUCTION: Under the scope of the Specific Project “Implantation improvement for the main crops”, was initiated an analysis of the characteristics of seeding in different agricultural regions of Argentina. Such activity has as its main objective to collect information about the efficiency of the work and its critical aspects which influence the achievement of better results. The survey consists basically of two parts. First one consists of a questionnaire that collects descriptive information of the plots, seed, and machinery, and also about operating conditions, regulations and checks carried out before and during the work. The second stage consists in a field sampling when the crop was established, determining density, uniformity of the distribution on the seeding line, planting depth and its uniformity in the furrow and emergence. The aim of this survey is to obtain information enabling a reliable characterization of the conditions of seeding and the efficiency achieved in relation to them. With this sense, an integral work was realized, collecting field data and planters information from 24 establishments located in the northern , at the localities of Pergamino and Rojas (Argentina) among September and October of 2006, and its subsequent evaluation.

METHODOLOGY : During the maize seeding period in the 06/07 campaign was relieved the characteristics of the machinery, the conditions under which the work was performed and the results of planting lots in production in 24 establishments in EEA Pergamino influence area, in Buenos Aires, Argentina.

CIGR - International Conference of Agricultural Engineering XXXVII Congresso Brasileiro de Engenharia Agrícola

Brazil, August 31 to September 4, 2008

There was used a template of survey developed under the mentioned project in order to characterize the work of seeding, following the proposed test methodology of Standard ISO 7256/1: Seeding Equipment-Test methods-Part 1: Single seeds drills (Precision drills).

The parameters relieved to field were the following: Seedling density, uniformity of the distribution on the seeding line, planting depth and its uniformity in the furrow and emergence uniformity. The achievement percentage (or implantation efficiency) was calculated using the percentage relation between the seedling density and the seeding density, expressed as viable seeds. From these measurements, the following statistical analyses were realized:

Seedling density and achievement percentage : By means of hypotheses testing, which follows a Student's t test distribution, it was established whether the density of seedlings presented or not statistically significant difference at 5% with the corresponding seeding density. Uniformity of distribution in the seeding line : This parameter, which is equivalent to quality of seeding, was estimated by the percentage of acceptable (normally sown) and the standard deviation in the line of seeding. To calculate the acceptable percentage, the mean separation between seedlings in the seeding line was taken as reference distance (Xref). Any separation between consecutive seedlings among 0,5 Xref and 1,5 Xref were considered like acceptable (A). When the separation was lower than 0,5 Xref was calculated as multiple deliveries (D), whereas the seedlings presenting distances greater than 1,5 Xref, were considered as misses (M). Another way of estimating the uniformity of the distribution is using the standard deviation, which quantifies the dispersion of the observations respect of the average sample. To determine the existence or not, of statistically significant differences between particular cases, there were realized tests of homogeneity of variances with a level of significance of 5 %. Uniformity in the seeding depth and in emergence: Both parameters were estimated on the basis of the corresponding standard deviation, for which the statistical analysis is identical to the mentioned in the previous item.

Multivariate analysis: It is used for finding relations between the parameters mentioned previously and themselves, as well as between them and the explanatory variables that arise from the characteristics of the machinery and the ones that arise from the ambient conditions in which the seeding was realized. The purpose of this methodology is to analyze simultaneously information sets, which is to analyze with several variables every parameter of study. Among the different multivariate technologies existing, it was used Principal Components Analysis, which analyzes the interrelationships of the variables, presenting them in terms of a minor number of variables, named principal components. The variables with which this analysis was done, are the following: a) Machinery and operative variables. a1) Age of the machine (years) a2) Speed (km/h) a3) Distance between rows (mm) b) Variables that refer to implantation quality b1) Achievement Percentage b2) Standard deviation in the seeding line (mm) b3) CV length, variation coefficient of the seedlings height (%) b4) CV depth, variation coefficient of the seeding depth (%) b5) Acceptable (seeds sowed between 0,5 Xref and 1,5 Xref) b6) Multiple deliveries (seeds sowed to less separations than 0,5 Xref)

CIGR - International Conference of Agricultural Engineering XXXVII Congresso Brasileiro de Engenharia Agrícola

Brazil, August 31 to September 4, 2008

b7) Missing (seeds sowed to greater separations than 1,5 Xref)

Correlation Analysis and Regression Analysis: They were used for determining the degree and type of association between certain variables.

Analysis of correspondence: It was used to analyze from a graphical point of view, the relations of dependence and independence of a set of categorical and metric variables. When the degree of association is high, these appear in the graphic relatively close.

RESULTS AND DISCUSSION: Next it is shown the most relevant information contributed by the surveys in each of the following items:

Planters Pool and practices of seeding 40 % of the analyzed establishments effected the seeding with previous tillage whereas 60 % did it by means of direct seeding. It is important to emphasize that still in the cases where the implantation was done by previous tillage, practically the totality of the planters used were for direct seeding. The distancing between lines predominant was of 525 mm (70 % of the whole). The average age of the planters pool is 7 years, with a modal value of 3 years. Associating these two variables, it arises that with the distancing between lines of 525 mm the average age is 5 years whereas, to 700 mm, it is 10 years In relation to the state of conservation and maintenance, 52 % is in very good state and 48 % in good state. The wide of modal labor is 11 lines. With respect to the practice of the fertilization at the moment of the seedtime, the totality of the interviewed people does it, 34 % does it in the furrow, 53 % of lateral form to the line of seeding and 13 % realizes both forms of fertilization.

Characteristics and results of the seeding The preceding culture in all the polled establishments was soybean. The most frequent value as for coverage of stubble was 90 % with an average of 56 %, being the dampness of the same one predominantly very dry and dry. Soil condition to the moment of seeding was extremely favorable. The seeding density of used was relatively constant, reaching in average to 78.500 seeds for hectare. The density used by those that implanted the maize with previous tillage was 79.000 seeds for hectare vs. 78.300 seeds for hectare in direct seeding. The population of plántulas obtained to 17 days of the seeding went of 67.805 plántulas for hectare, which throws a percentage of average achievement (efficiency of implantation) near to 85 %. The seeds considered acceptably sowed fluctuated between a minimum of 54 % and a maximum of 91 %. The average value of the speed of advance turned out to be 6,3 km/h. The depth of effective seeding changed between a maximum of 71 mm and a minimum of 35 mm and the coefficient of variation fluctuated between a maximum of 18,5 % and a minimum of 8,6 %. In 70 % of the cases, the depth of observed seeding turned out to be practically coincidental with the declared depth. In 30% remaining, some and others presented significant differences .

Figure 1 shows in a graphical biplot contributed by the multivariate analysis of principal components the observations and the variables in a same model. The Achievement Percentage (seedling density / viable seeds seeded) was associated in positive way with % of acceptable and in a negative way with the rest of the variables. The operative variable, speed of advance, was narrowly and positively associated with the amount of misses and multiple deliveries, and consequently, its increase harmed the quality of seedtime.

CIGR - International Conference of Agricultural Engineering XXXVII Congresso Brasileiro de Engenharia Agrícola

Brazil, August 31 to September 4, 2008

4,00

Antigüedad

2,50 Distancia CV Prof

1,00 CP2

CV Largo

Aceptables Fallas Múltiples % logro Velocidad

-0,50

STD

-2,00 -3,00 -1,38 0,25 1,88 3,50 CP 1

FIGURE 1: Graph Biplot of the observations and the variables

With the intention of finding the presence of relations between the constructive characteristics of the drills and the obtained results there was correspondence analysis. a) To major age of the equipments, it is possible to wait for a decrease in the acceptably sowed seeds and in the efficiency of implantation as well as an increase in the values of multiple deliveries and faults. b) The advance speed shows a negative relation with the acceptable seeds and positive with the distribution uniformity in the line of seeding and with the faults. c) There are no considerable differences on the different diameters of the cleavers, nevertheless as for acceptably sowed seed, uniformity of seeding and the CV of the height of the plántulas, the results would indicate that the best behavior is associated with cleavers of intermediate diameters (16 and 17 inches) d) There is no relation between the diameter and the quantity of waves. e) There are no significant differences between the turbo cleavers and the smooth ones. f) The seed tube showed influence neither in the quantity of acceptable seeds nor in the uniformity in the line of seeding. g) The lateral fertilization to the furrow of seeding as well as the simple fertilization, improve the quantity of acceptably sowed seed.

CONCLUSION: Drills characteristics, such as age and fertilization system, as well as the working speed, they determine the seeding results influencing the quality of implantation obtained.

REFERENCES: INTERNACIONAL ORGANIZATION FOR STANDARIZATION. Seeding Equipment. Test methods. Part 1: Single seeds drills (Precision drills) ISO 7256/1, 1984. 14 pp