Fernando José Hawerroth

Bio: Fernando José Hawerroth is an academic researcher from Empresa Brasileira de Pesquisa Agropecuária. The author has contributed to research in topics: Chilling requirement & Dormancy. The author has an hindex of 11, co-authored 63 publications receiving 367 citations. Previous affiliations of Fernando José Hawerroth include Universidade Federal de Pelotas.

Das Américas para o Mundo: origem, domesticação e dispersão do abacaxizeiro

Abstract: The pineapple(Ananas comosus (L.) Merril), fruit-symbol of tropical and subtropical regions, originated in the Americas, was widespread throughout the world mainly by european navigators because of its aroma and flavor, and lush appearance. Named as "King of Colonial Fruits", pineapple is one of the eleven most produced fruit in the world, growing consumed in every continent, with Brazil as the largest producer. Then, the objective of this literature review is to approach the pineapple history, contemplating its botany, origin and dispersion in the world and its current scenario and issues related to germplasm conservation and breeding.

Budbreak in 'Imperial Gala' and 'Fuji Suprema' apples by use of Erger and calcium nitrate

Abstract: Despite the high efficiency of some chemicals on budbreak induction of temperate fruit trees, the high toxicity showed by these compounds is one of the main problems related to its use. Preliminary results indicated that Erger®, an organic nitrogen compound, combined with calcium nitrate, has similar effect to hydrogen cyanamide, with the advantage of being less dangerous to the environment. Thus, the present study aimed to evaluate the efficiency of Erger® and calcium nitrate as budbreak promoter in apple trees. The experiment was carried out in Cacador/SC, in 2007, where was done the application of different budbreak promoters in 'Imperial Gala' and 'Fuji Suprema' apples. The budbreak promoters tested were Erger® 3% + calcium nitrate 3%, Erger® 5% + calcium nitrate 5%, Erger® 7% + calcium nitrate 7%, mineral oil 3.2% + 0.34% hydrogen cyanamide and control (without application). It was evaluated occurrence dates of early, full and end blooming stages, budbreak of axillary and terminal buds, axillary budbreak uniformity and fruit set. The budbreak promoters increased significantly axillary and terminal budbreak, and it increased the budbreak uniformity and the blooming overlap of 'Imperial Gala' and 'Fuji Suprema' apples. Because of negative effects on fruit set of 'Imperial Gala' apples, it is indicated Erger® and calcium nitrate application at concentrations below 7%.

Chilling privation during dormancy period and carbohydrate mobilization in Japanese pear trees

Abstract: The flower bud abortion is one of the main problems that limit commercial pear (Pyrus pyrifolia) production in the southern region of Brazil. Insufficient chilling during the dormancy period is known as the main factor of this problem. One of the hypotheses to explain this problem is that the starch mobilization and carbohydrate fluxes to the buds are impeded when mild temperatures occurred during winter. This study compared the total soluble sugars (TSS) and reducing sugars (RS) concentrations, the cell wall acid invertase (CWAI - EC 3.2.1.26) and sucrose-phosphate synthase (SPS - EC 2.4.1.14) activities in wood of branches and floral buds of Japanese pear trees cv. Housui, grafted on Pyrus calleryana and submitted to chilling conditions during the dormancy period. Treatments were: (i) natural conditions; (ii) continuous artificial chilling; (iii) alternating temperatures, and (iv) total chilling privation. TSS and RS contents, as well as CWAI and SPS activities in tissues of branches that received insufficient chilling were lower than those that received sufficient chilling during winter. The starch concentration was superior in wood tissues of branches kept under chilling privation. The chilling privation disturbs carbohydrate mobilization in pear trees, reducing the sucrose synthesis capacity in wood tissues (source) and sucrose importation by the floral buds (sink).

Phenology of wild apple species like pollinators of gala and fuji cultivars

Abstract: - The correct choice of pollinator cultivars is an important management factor for obtaining high productivity in appletrees. Many apple production regions in the world adopt wild apple species with the specific purpose of pollination. However, thereis little information about the use of this species in the climatic conditions of South Brazil. The objective of this work was to evaluatethe phenological behaviour of thirteen wild apple species in relation to the fowering compared to Gala and Fuji cultivars, during sevenyears (2001-2007). All species and apple cultivars studied were conduced on M-9 rootstock. The wild apple species showed highvariability at flowering and length throughout the years. The major overlap of the flowering period and major regularity throughoutthe years was obtained between Gala and Fuji cultivars. ‘Prof. Spengler’, ‘Profusion’, ‘Winter gold’ and ‘John Downil’ are the wildapple species with the greater potential of use like pollinators, which can be used like a pollination suplement of Gala and Fujicultivars. The species

Redução do acamamento em aveia-branca com uso do regulador de crescimento etil-trinexapac

Abstract: The objective of this work was to evaluate the effects of the application of doses of the plant growth regulator trinexapac‑ethyl on plant height, lodging index, and grain yield of the white oat cultivar Barbarasul at different cultivation environments and nitrogen doses. The experiments were conducted in the 2010 and 2011 crop seasons in the municipalities of Capao do Leao and Augusto Pestana, in the state of Rio Grande do Sul, and in the 2010 and 2012 crop seasons in the municipality of Lages, in the state of Santa Catarina, Brazil. A randomized complete block design was used, in a 4x2x6 factorial arrangement (dose of trinexapac‑ethyl, development stage, and environment), with four replicates consisting of 3.0 m 2 plots. In each environment, nitrogen fertilization was done with 30 and 90 kg ha ‑1 N. The evaluated traits were plant height, lodging index percentage, and grain yield. The application of the growth regulator trinexapac‑ethyl, at the doses of 100 to 150 g a.i. ha ‑1 in 'Barbarasul' white oat plants, in the E 31 and E 32 development stages, reduces plant height and the percentage of lodging, without harming grain yield. The intensity of the reduction in lodging depends on the conditions of the cultivation environment.

Transcriptomic analysis of ‘Suli’ pear (Pyrus pyrifolia white pear group) buds during the dormancy by RNA-Seq

Abstract: Bud dormancy is a critical developmental process that allows perennial plants to survive unfavorable environmental conditions. Pear is one of the most important deciduous fruit trees in the world, but the mechanisms regulating bud dormancy in this species are unknown. Because genomic information for pear is currently unavailable, transcriptome and digital gene expression data for this species would be valuable resources to better understand the molecular and biological mechanisms regulating its bud dormancy. We performed de novo transcriptome assembly and digital gene expression (DGE) profiling analyses of ‘Suli’ pear (Pyrus pyrifolia white pear group) using the Illumina RNA-seq system. RNA-Seq generated approximately 100 M high-quality reads that were assembled into 69,393 unigenes (mean length = 853 bp), including 14,531 clusters and 34,194 singletons. A total of 51,448 (74.1%) unigenes were annotated using public protein databases with a cut-off E-value above 10-5. We mainly compared gene expression levels at four time-points during bud dormancy. Between Nov. 15 and Dec. 15, Dec. 15 and Jan. 15, and Jan. 15 and Feb. 15, 1,978, 1,024, and 3,468 genes were differentially expressed, respectively. Hierarchical clustering analysis arranged 190 significantly differentially-expressed genes into seven groups. Seven genes were randomly selected to confirm their expression levels using quantitative real-time PCR. The new transcriptomes offer comprehensive sequence and DGE profiling data for a dynamic view of transcriptomic variation during bud dormancy in pear. These data provided a basis for future studies of metabolism during bud dormancy in non-model but economically-important perennial species.

A Systematic Approach to Discover and Characterize Natural Plant Biostimulants.

Abstract: The use of natural plant biostimulants is proposed as an innovative solution to address the challenges to sustainable agriculture, to ensure optimal nutrient uptake, crop yield, quality, and tolerance to abiotic stress. However, the process of selection and characterization of plant biostimulant matrices is complex and involves a series of rigorous evaluations customized to the needs of the plant. Here, we propose a highly differentiated plant biostimulant development and production platform, which involves a combination of technology, processes, and know-how. Chemistry, biology and omic concepts are combined/integrated to investigate and understand the specific mode(s) of action of bioactive ingredients. The proposed approach allows to predict and characterize the function of natural compounds as biostimulants. By managing and analyzing massive amounts of complex data, it is therefore possible to discover, evaluate and validate new product candidates, thus expanding the uses of existing products to meet the emerging needs of agriculture.

Self-incompatibility (S) alleles of the Rosaceae encode members of a distinct class of the T2/S ribonuclease superfamily. [Erratum: Aug 1996, v. 252 (1/2), p. 222]

Abstract: Stylar riboncleases (RNases) are associated with gametophytic self-incompatibility in two plant families, the Solanaceae and the Rosaceae. The self-incompatibility-associated RNases (S-RNases) of both the Solanaceae and the Rosaceae were recently reported to belong to the T2 RNase gene family, based on the presence of two well-conserved sequence motifs. Here, the cloning and characterization of S-RNase genes from two species of Rosaceae, apple (Malus × domestica) and Japanese pear (Pyrus serotina) is described and these sequences are compared with those of other T2-type RNases. The S-RNases of apple specifically accumulated in styles following maturation of the flower bud. Two cDNA clones for S-RNases from apple, and PCR clones encoding a further two apple S-RNases as well as two Japanese pear S-RNases were isolated and sequenced. The deduced amino acid sequences of the rosaceous S-RNases contained two conserved regions characteristic of the T2/S-type RNases. The sequences showed a high degree of diversity, with similarities ranging from 60.4% to 69.2%. Interestingly, some interspecific sequence similarities were higher than those within a species, possibly indicating that diversification of S-RNase alleles predated speciation in the Rosaceae. A phylogenetic tree of members of the T2/S-RNase superfamily in plants was obtained. The rosaceous S-RNases formed a new lineage in the tree that was distinct from those of the solanaceous S-RNases and the S-like RNases. The findings suggested that self-incompatibility mechanisms in Rosaceae and Solanaceae are similar but arose independently in the course of evolution.