Yellow plums *(Prunus domestica L)* conventionally and organically grown in the same farm were selected to study the influence of different agronomic practices on antioxidant vitamins (ascorbic acid, vitamin E, β-carotene) and phenolics (total polyphenols, phenolic acids, flavonols) concentration.
Three organic cultivations were performed: tilled soil, soil covered with trifolium, and soil covered with natural meadow.

The test that the document uses is the t student, and I'm going to use the same test.

Acording to Ginebra et al (2004) they analyzed different chemical physical properties, and they found some cultivars of plum fruit to be different if they are grown on ecological conditions or in convencional conditions.

The fructose in plum cultivar: in organic conditions is 1.38 ± 0.3g/100 g and in convencional conditions is 1.08 ± 0.2g/100 g. The authors "p < 0,05", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 0.0121, so there are significant differences, as the study declare.

The glucose in plum cultivar: in organic conditions is 2.11 ± 0.6g/100 g and in convencional conditions is 1.97 ± 0.8g/100 g. The authors "p < 0,05", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 0.6474, so there are not much significant diferences but the calculated "p" of the study is not correct.

The sucrose in plum cultivar: in organic conditions is 1.82 ± 0.5g/100 g and in convencional conditions is 2.23 ± 0.1g/100 g. The authors "p" do not appeard but I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 0.014, so thats the "p" that in the article do not appeard.

The sorbitol in plum cultivar: in organic conditions is 0.96 ± 0.2g/100 g and in convencional conditions is 1.16 ± 0.7g/100 g. The authors "p < 0,05", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 0.3731, so there are not much significant diferences but the calculated "p" of the study is correct.

The total sugar in plum cultivar: in organic conditions is 6.27 ± 0.4g/100 g and in convencional conditions is 6.44 ± 1.8g/100 g. The authors "p < 0,05", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 0.7629, so there are not much significant diferences but the calculated "p" of the study is not correct, the author have made a mistake.

The citric acid in plum cultivar: in organic conditions is 25.7 ± 1.0g/100 g and in convencional conditions is 27.0 ± 2.1g/100 g. The authors "p < 0,05", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is:0.0786, so there are not much significant diferences but the calculated "p" of the study is not correct, the author have made a mistake.

The sucrose in plum cultivar: in organic conditions is 1.98 ± 0.2g/100 gand in convencional conditions is 1.98 ± 0.3 g/100 g. The authors "p" do not appeard but I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 1.0000, so there are not much significant diferences.

The protocatecuic in plum cultivar: in organic conditions is 0.6 ± 0.061g/100 g and in convencional conditions is 0.8 ± 0.03g/100 g. The authors ", p < 0.001", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: 0.0425, there are significant differences, so the study is not correct, the author have made a mistake..

The ferulic in plum cultivar: in organic conditions is 9.3 ± 0.42g/100 g and in convencional conditions is 8.0 ± 0.63g/100 g. The authors "p < 0.001", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: less than 0.0001, so is considered to be extremely statistically significant as the study declare.

The chlorogenic in plum cultivar: in organic conditions is 37.5 ± 2.94g/100 g and in convencional conditions is 25.2 ± 1.25g/100 g. The authors "p < 0,05", if I calculate the t student test knowing n= 11, with the next websit Graphad Student t Test Online The calculate "p" is: less than 0.0001, so is considered to be extremely statistically significant as the study declare.

Lombardi Ginebra, Lucarini Massimo, et al (2004), Nutrients and Antioxidant Molecules in Yellow Plums (Prunus domestica L.) from Conventional and Organic Productions: A Comparative Study