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Biostimulant use in the world is increasing more and more, in this sense, this work was carried out at the Tecomatlan Institute, Puebla, Mexico, to evaluate the influence of the Quitomax® use and the inoculation with two strains of mycorrhizae on the growth and development of tomato plants. Seedlings were produced in a shade house, in trays of 200 cells, filled with a commercial substrate, under same treatments that would later be applied in field conditions, which consisted of a control where seeds were imbibed in water for three hours. The same time was used when mycorrhiza was used, while the two strains of mycorrhizae (Incam4 and Incam11) were applied by coating the seeds, so that six treatments were formed, since both biostimulants were also used in combination. A randomized block design with four replications was used for the distribution of treatments under field conditions. At transplanting, each inoculum was applied to the root system and Quitomax® was applied sprayed to the foliage at seven and 28 days, in the treatments that required it. In the postures, height growth was evaluated every seven days and stem diameter at the transplanting time. Under field conditions, growth and yield variables were evaluated. In the posturing phase, the treatments did not modify stem diameter with respect to the control, and had a greater effect on plant height. Under field conditions, the effect was more marked on yield than on the growth variables evaluated, highlighting the combined action of Quitomax® with the Incam4 strain. [ABSTRACT FROM AUTHOR]

Wilting of sugarcane is produced by a complex of Fusarium species, such as F. andiyazi and F. sacchari, which induce rotting of roots. In order to control this disease and reduce the use of fungicides, biological control has been proposed by means of antagonists of the genus Trichoderma. The objective of this study was to evaluate in vitro and in sugar cane plants the antagonistic capacity of strains of Trichoderma against F. andiyazi and F. sacchari. The hypothesis was that at least one strain of Trichoderma inhibits the growth in vitro of Fusarium and favors the development of the sugarcane plants. Eighteen strains of Trichoderma were isolated and their percentage of inhibition was determined on the mycelial growth of Fusarium species with the technique of dual culture in potato dextrose agar culture medium. The experimental design was completely randomized, with four replicates per treatment. The degree of antagonism of Trichoderma was evaluated at 13 d. The strains T2 and T8 which showed the best characteristics of antagonism were selected for the in vivo bioassay. For the evaluation in vivo, the sterile substrate was inoculated with F. andiyazi and F. sacchari, and the roots of sugarcane plants with strains T2 and T8 of Trichoderma in a design of randomized blocks, with three blocks and three replicates for each treatment. The variables evaluated were plant height (cm), fresh and dry root biomass (g), number and diameter of stems (mm) and root length (cm). The strains T2 and T8 were determined with morphological and molecular identification as T. asperellum and T. koningiopsis. The effect of these species on the sugarcane plants was beneficial, given that they increased plant height, along with length, wet and dry biomass of roots. [ABSTRACT FROM AUTHOR]

The specific (SCA) and general combinatorial aptitude (GCA) are used to identify hybrid combinations between inbred lines with higher or lower yield than that expected from the average behavior of the parental lines. The objective of this study was to evaluate the GCA of eight lines and the SCA of their inbreeding. We hypothesized that crosses between lines with contrasting characteristics would produce outstanding hybrids. During autumn 2011 the crosses were formed and in spring 2012 evaluated at the Marín experimental field, Universidad Autónoma de Nuevo León, México. The eight evaluated inbred lines were in a complete blocks experimental design at random with three repetitions. Genetic analysis was performed with the design II North Carolina mating from Comstock and Robinson. The progenitors, considered as males M-16 (4.74 t ha-1), M-11 (4.60 t ha-1) and M-14 (4.21 t ha-1) and females H-8 (4.26 t ha-1), H-2 (4.15 t ha-1) and H-4 (4.13 t ha-1) showed the greatest effects of GCA. Major effects on SCA were observed in the H-8×M-16 (4.99 t ha-1), H-8×M-11 (4.83 t ha-1) and H-2×M16 (4.78 t ha-1) crosses. The additive variance for grain yield was 0.03 and exceeded the dominance variance (-0.34); heritability in the strict sense was 7.65% and female variance (0.0075) was higher than that of males (0.0012). [ABSTRACT FROM AUTHOR]

Under dry conditions the establishment of eight varieties of Cenchrus purpureus, obtained by crossing and tissue culture in the Institute of Animal Science, Cuba, was evaluated. A random block design with five replications was applied. The varieties were: 115 (control), 442, 423, 30, H-48, 457, H-31 and 452. The highest number of stems/bunch was observed in materials H-31 (8.1), 452 (8.2), 423 (7.6) and H-48 (7.5) and the highest percentage of dead stems (P = 0.0002) at 423 (22 %) and H-48 (15 %). The varieties with the highest height (P <0.0001) were the 30 (170.0cm), 457 (160.4 cm) and H-48 (156.4cm), and had lower height 442 (89.8cm). The highest number of leaves (P <0.0001) was observed in H-31 (231.7) and 452 (210.1) and the lowest in 30 (102.4). The percentage of green leaf of the total (P <0.0001) was higher for the H-31 (51.3 %) and the lowest for 115 (30.3 %), 423 (29.9 %) and H-48 (31.2 %). The highest number of internodes per stem was found in 115 (16.4), followed by 30 (13.7), and was lower in 442 (6.9) and 452 (8.7) (P <0.0001). The best yield (P = 0.0010) was 442 (7.1t / ha DM), and the worst was 115 (2.1t / ha DM) and 457 (1.7t / ha DM). In 442, 451 and H-31 outstanding values in several of the evaluated indicators were registered. This was not the case for H-48 and 30. It is concluded that the varieties studied showed differences in their growth at the establishment time, although this was not affected. It is recommended to continue the evaluation under cutting or grazing. [ABSTRACT FROM AUTHOR]

In order to establish possible relations among statistical indicators in models of parametric and non-parametric analysis of variance, belonging to completely randomized and random block experimental designs, the categorical principal component analysis was used because they are quantitative and qualitative. The models of analysis of variance of simple classification, with 16 experiments, were selected, as well as those of double classification with five experiments. An amount of 100 discrete and categorical variables were analyzed. A matrix of data was designed using the indicators of completely randomized designs and the test of Kruskal-Wallis, which is its non-parametric homologue, the model of random blocks with its non-parametric homologue, and the test of Friedman. The categorical principal component analysis showed adequate reliability and a variability percentage explained with 0.94. The indicators with more importance in the first dimension are related to probability of type I error and power, showing absolute values close to one and allowing to determine their contribution in this study. The results evidenced the existing relations among the analyzed statistical indicators, from the high degree of positive correlation over 0.90 among the values of probability of type I error in the F test of Fisher (with and without transformation) and its non-parametric homologue test, as well as the high negative correlations, existing between around 0.8 and 0.93 of them with values of power (with or without data transformation). It is necessary to continue the analysis for different data distributions and sample sizes. [ABSTRACT FROM AUTHOR]