Rafael Gustavo Ferreira Morales

Yield and soluble solids contents of fruits of strawberry cultivars in protected cultivation

Protected cultivation is an alternative to control the climatic effects in different places and times of planting, however, its effects and interactions with the strawberry crop are little known. The goal of this study was to evaluate the effects of three cropping systems (high tunnel, low tunnel and field) on yield, mean fruit mass and the soluble solids contents of strawberry cultivars Dover, Camarosa, Sweet Charlie and Oso Grande in Guarapuava. Camarosa cultivar presents an excellent performance regarding yield and mean fruit mass in high and low tunnel cultivation; hence, these cropping system can be indicated. Fruits of Sweet Charlie cultivar had the highest content of soluble solids in all the cultivation environments. Yield and mean fruit mass obtained from high and low tunnels were significantly higher than in the field. The environment high tunnel allowed greater accumulation of soluble solids, differing significantly from other evaluated environments.

Genetic similarity among strawberry cultivars assessed by RAPD and ISSR markers

Most strawberry (Fragaria × ananassa Duchesne) cultivars used in Brazil are developed in other countries, it became clear the need to start the strawberry breeding program in the country. To start a breeding program is necessary the genetic characterization of the germplasm available. Molecular markers are important tools that can be used for this purpose. The objectives of the present study were to assess the genetic similarity among 11 strawberry cultivars using RAPD and ISSR molecular markers and to indicate the possible promising crosses. The DNA of the eleven strawberry cultivars was extracted and amplified by PCR with RAPD and ISSR primers. The DNA fragments were separated in agarose gel for the RAPD markers and in polyacrylamide gel for the ISSR markers. The genetic similarity matrix was estimated by the Jaccard coefficient. Based on this matrix, the cultivars were grouped using the UPGMA method. The dendogram generated by the RAPD markers distributed the cultivars in three groups while the ISSR markers generated two groups. There was no direct relationship between the marker groups when the two types of markers were compared. The grouping proposed by the ISSR markers was more coherent with the origin and the genealogy of the cultivars than that proposed by the RAPD markers, and it can be considered the most efficient method for the study of genetic divergence in strawberry. The most promising crosses, based on the genetic divergence estimated from the RAPD and ISSR molecular data were between the Tudla and Ventana and the Oso Grande and Ventana cultivars, respectively.

Genetic divergence among Brazilian garlic cultivars based on morphological characters and AFLP markers.

Outside its centers of origin, garlic propagates only asexually. Since asexual reproduction leads to the absence of meiotic recombination, the main garlic cultivars available for cultivation have arisen from the accumulation of somatic mutations in early cultivars. Thus, it is common for a single clone to have different names in different regions. This study aimed to evaluate the genetic diversity of 20 garlic cultivars by using morphological characters and amplified fragment length polymorphism (AFLP) markers to identify possible duplicate cultivars. We assessed 28 morphological characters related to the leaves, bulbs, and bulbils of the garlic plant and divided them into two categories: quantitative and qualitative (14 characters each). For molecular marker-based analysis, we used three AFLP primer combinations. Genetic divergence was calculated using the Jaccard coefficient; the cultivars were grouped using unweighted pair-group mean analysis. The average genetic divergence detected using the morphological characters was 2.30 (range, 0.45-4.70). Plant height and coat adhesion exhibited the highest divergence among the cultivars. The average genetic diversity based on AFLP data was 43% (range, 0-79%). Dendrograms derived from both techniques divided the cultivars into two groups: noble and semi-noble. Together with the divergence within groups, the correlation between morphological and molecular data suggested that the cultivars in the noble group had greater phenotypic stability than those in the semi-noble group. Analysis of Jonas and Quitéria cultivars using these two techniques revealed only slight differences, suggesting that these cultivars may be clones or have a high degree of kinship.

The role of glandular and non-glandular trichomes in the negative interactions between strawberry cultivars and spider mite

In tropical countries, spider mite (Tetranychus urticae Koch) is a major pest of strawberries. This pest is mainly controlled by the application of pesticides. Use of pest-resistant cultivars is a healthy and environment-friendly alternative to pesticide use. This paper describes the role of glandular and non-glandular trichomes in the interaction between strawberry cultivars and spider mite. The methodology used in this study was based on two bioassays. First, the thumbtack bioassay of Weston and Snyder was used to differentiate strawberry cultivars in terms of the distance travelled by the mites. Second, different types of trichomes present on the abaxial surface of the strawberry leaves were identified and counted. The results of this study showed a significantly negative correlation between the distance travelled by the spider mites and the density of glandular trichomes on the strawberry plant. The cultivars Camino Real and Dover had the highest densities of glandular trichomes and the shortest distance travelled by the mites. In contrast, the cultivars Ventana and Toyonoka had the lowest density of glandular trichomes and the longest distance travelled by the spider mites. The high density of glandular trichomes might have been responsible for the spider mite non-preference to the Camino Real and Dover strawberry cultivars, whereas the non-glandular trichomes minimally contributed to this non-preference. The results of this study affirm the role of glandular trichomes in negative interactions between strawberry and spider mites.

Desempenho agronômico e heterose de genótipos de cebola

The use of onion hybrids in Brazil is still recent, with little information regarding the gains from heterosis. However, the first step to exploit the heterosis is the evaluation of available germplasm. Due to the need for genotypes adapted to the climatic conditions of South-Central region of Parana state, Brazil, this study aimed to evaluate the agronomic performance of 19 hybrids and 50 inbred lines of onion, as well as the heterotic gain of six of these hybrids. The experimental design was randomized blocks with three replications. The evaluated traits were yield, average weight of the bulbs, commercial classification of bulbs, waxy of the leaves and cycle. In general the hybrids were superior to the lineages in yield and average bulb weight and had lower cycle. The heterotic gain in hybrids was evident, indicating the viability of hybrids for cultivation in the region. Hybrids 2572, 2573 and 2578 are promising due their high yield, earliness cycle and better classification of the bulbs. The lineages 2507-1 and 2983 provided the highest heterotic gain for the yield of the hybrid 2857, which was classified in the group of earliest genotypes, showing an inverse correlation between these two characters.

Garlic vernalization and planting dates in Guarapuava

Several attempts have been made in order to produce garlic out of season in Southern Brazil, aiming to reduce dependence on imports. The use of cold storage before planting is a possible alternative. Another possibility could be forward planting dates using early cultivars, more tolerant to diseases and less demanding in temperature and photoperiod conditions. The objective of the present study was to evaluate the effects of three vernalization periods (30, 40 and 50 days) and three planting dates (23/03, 23/04 and 23/05) on the yield of two garlic cultivars (Cacador and Quiteria). A randomized block design with three replications was used. The assessed traits were plant emergence, plant height, secondary plant growth, total yield and classification of marketable bulbs. The plant emergence and plant height increased in the first cultivation period. The yield of marketable bulbs of the Quiteria cultivar increased on the first two planting dates and the Cacador cultivar showed the highest yield of marketable bulbs on the second planting date. The third planting date provided a decrease in the secondary growth of the Cacador cultivar plants. The 30-day vernalization period promoted lower secondary growth of Quiteria cultivar plants. The 40-day vernalization period, which allowed better adaptation of both cultivars to photoperiod and temperature, resulted in good vegetative and productive development in the region of Guarapuava, Parana State, Brazil.

Tomato yield and soil chemical attributes depending on previous cover crops

The influence of different cover crops was evaluated over the agronomic performance of tomato hybrids for industrial processing, as well as its effect over soil chemical attributes. The experimental design was completely randomized, in a split plot scheme, with four replications. Main treatments (plots) were composed of winter cover crops (oat, hairy vetch, clover and radish) and of a fallow area (spontaneous vegetation). Subplots were composed of four processing tomato hybrids (AP529, AP533, Katia and Sicilio). We evaluated the total production (TP), marketable production (CP), average mass of marketable fruits (AMCF) and number of marketable fruits (NCF). Chemical analysis of soil was done in two stages: one week preceding implantation of cover crops and in the phase of tomato implantation. Highest TPs were obtained in treatments in which cover crops were composed by hairy vetch and radish. However, although hairy vetch has caused an increase in TP, no difference between covers was obtained in relation to CP. Sicilio hybrid presented the greatest AMCF, however, its TP was lower than expected. This fact is related to lower NCF, which was half of the observed in AP529 and AP533 hybrids. Radish cover increased phosphorus, calcium and potassium in soil and this could be one of the factors responsible for the increase of TP provided by radish. On the other hand, oat has caused inverse effect, reducing availability of Ca and K. All covers have increased organic matter in soil, the major increment being presented by oat. Based on these results we conclude that hairy vetch and radish are the most indicated plants for cover preceding tomato cultivation.

Caracterização morfológica, produtividade e rendimento comercial de cultivares de alho

Brazil could increase garlic production up to the point of supplying the internal demand. To achieve this success, it is necessary to evaluate the maximum number of cultivars to establish the best ones for each region. Therefore, we aimed to evaluate economic yield and quality of bulbs of 20 garlic cultivars in Center-South Parana state, Brazil. The experiment was carried out between March and September 2009, in Guarapuava, Parana state. Experimental design was randomized blocks with three replications. The treatments consisted of twelve seminoble and eight noble garlic cultivars. We evaluated the total production (TP), commercial production (CP) and commercial classification of bulbs; secondary bulb growth; and six characteristics related to the plant morphology: pseudostem diameter, length and leaf width, length, width and number of cloves. Noble group cultivars have presented TP superior to seminoble cultivars. However, there was no difference in relation to CP. Among cultivars of noble group, San Valentim presented greater CP bulbs, with 8,9 t ha-1. Noble group cultivars have presented higher percentual of bulbs in classes 6 and 7, especially the cultivars Chonan, with 40.3% of the bulbs in the class 7 and cultivar Ito, with 75% of the bulbs in classes 6 and 7. The opposite was observed in the seminoble group, since most bulbs of this group were found in classes 3, 4 and 5. Among the evaluated cultivars, San Valentin showed to be better adapted to the edafoclimatic conditions of the region, presenting a great yielding potential.

PRODUTIVIDADE E QUALIDADE PÓS-COLHEITA DE CULTIVARES DE CEBOLA EM SISTEMAS DE CULTIVO ORGÂNICO E CONVENCIONAL

ABSTRACTYIELD AND POSTHARVEST QUALITY OF ONION CULTIVARS IN THE ORGANICAND CONVENTIONAL CROPPING SYSTEMS The study aimed to evaluate yield, physical-chemical features and post-harvest losses of onioncultivars grown in organic and conventional cropping systems. Total yield and average weight of bulbs,content of soluble solids, titratable acidity, dry weight and pH. Were evaluated Besides these characteristics,post-harvest losses were also evaluated, with observation of mass loss. The bulbs were stored in coldchamber at a temperature of 3 ° C ± 1 o C and relative humidity of 75% ± 5% for 90 days. The organicsystem had higher yield than the conventional system, but did not differ significantly in other evaluatedcharacteristics. The hybrid Baia F 1 showed the greatest yield and the highest average masses of bulbs inboth cropping systems. The Red Creole cultivar showed higher values of soluble solids content and bulbsdry mass than other cultivars in the two cropping systems. These characteristics indicate that Red Creolecultivar is an excellent material for industrialization. Post-harvest evaluations showed that Red Creolecultivar had the highest reduction in the weight of bulbs in conventional and organic systems. Thisdata show that there is no influence of the cropping systems in the bulbs post-harvest conservation.Key words: Allium cepa L., yield, pyruvic acid, pungency.

Prediction of industrial tomato hybrids from agronomic traits and ISSR molecular markers.

Heterosis is a highly relevant phenomenon in plant breeding. This condition is usually established in hybrids derived from crosses of highly divergent parents. The success of a breeder in obtaining heterosis is directly related to the correct identification of genetically contrasting parents. Currently, the diallel cross is the most commonly used methodology to detect contrasting parents; however, it is a time- and cost-consuming procedure. Therefore, new tools capable of performing this task quickly and accurately are required. Thus, the purpose of this study was to estimate the genetic divergence in industrial tomato lines, based on agronomic traits, and to compare with estimates obtained using inter-simple sequence repeat (ISSR) molecular markers. The genetic divergence among 10 industrial tomato lines, based on nine morphological characters and 12 ISSR primers was analyzed. For data analysis, Pearson and Spearman correlation coefficients were calculated between the genetic dissimilarity measures estimated by Mahalanobis distance and Jaccards coefficient of genetic dissimilarity from the heterosis estimates, combining ability, and means of important traits of industrial tomato. The ISSR markers efficiently detected contrasting parents for hybrid production in tomato. Parent RVTD-08 was indicated as the most divergent, both by molecular and morphological markers, that positively contributed to increased heterosis and by the specific combining ability in the crosses in which it participated. The genetic dissimilarity estimated by ISSR molecular markers aided the identification of the best hybrids of the experiment in terms of total fruit yield, pulp yield, and soluble solids content.