INDOLEBUTYRIC ACID AND ZINC IN THE ROOTING OF ROOTSTOCK SEEDLINGS OF ‘CRAVO’ LEMON IN HYDROPONIC SYSTEM

It was intended to evaluate the influence of indolebutyric acid (IBA) and zinc upon the rooting and development of rootstock of ‘Cravo’ lemon tree transplants of bare root to the modified hydroponic system in the grafting stage. Plants of rootstocks were treated by immersion of their root system into the different solutions tested for 24 hours. The experiment was arranged in a completely randomized design with seven treatments composed of IBA doses of 50, 100 and 200 mg.L-1 and Enervig® which contains in its formulation 33.92 g.L-1 of Zn at 60, 90 and 120 ml.L-1, and distilled water as a control with three replications and nine plants per plot, amounting to 189 plants , 15 cm tall. The rootstocks were transplanted to the tubes and taken to the modified hydroponic system, being evaluated (1) the development of the plants and (2) the time needed for the rootstocks to reach the grafting stage, considered ideal between 5 and 6 mm in diameter. The treatment with a solution of 100 mg.L-1of IBA proved superior to the others in the development of height and biomass yield and tended to provide greater stem diameter development. The grafting point was obtained, on average at 70 days after transplanting and the production of Rangpur lime trees in a hydroponic system may be recommended. When the root system of the ‘Cravo’ lemon tree was treated with 100 mg.L-1 solution the IBA grafting point was obtained at 45 days after transplanting.

Damage to lemon tree caused by simulated drift of herbicides

The use of herbicides, in particular clomazone and glyphosate, applied in isolation or in a tank mix, is very common in rice, soybeans, corn and sugarcane fields and the drift of these herbicides can cause damage in sensitive species grown nearby. The purpose of this work was to evaluate the effects of the simulated drift of clomazone and glyphosate applied in an isolated way or mixed in a spray on lemon tree plants. The experiment was installed in a greenhouse in pots with a capacity of 15 L containing sieved soil and an experimental design of randomized blocks was adopted, arranged in a 3 x 5 factorial scheme, with four replications. Plants with two years of development were used. The treatments tested were, clomazone, glyphosate and both mixed, and the decreasing doses of the recommended commercial product: 100, 75, 50, 25 and 0% to simulate herbicide drift. Was evaluated variables, phytotoxicity at 14, 28, 46 and 100 days after application of treatments; plant height, crown volume, the trunk diameter of the rootstock, trunk diameter of the graft and trunk diameter at the grafting point at 0 and 100 days after application of treatments; and liquid assimilation of CO2 at 10 and 60 days after application of treatments. Among the tested herbicides, the one that presented the highest phytotoxicity and the lowest liquid assimilation of CO2 in lemon tree plants was the glyphosate + clomazone mixture. Increases in trunk diameter of the rootstock, grafting point, graft and crown volume did not show significant effects with simulated drift. The plant height presented a greater reduction with the increase of the herbicide doses, mainly glyphosate. That there are considerable losses in lemon tree plants when herbicide drift occurs, mainly by glyphosate and its mixture with clomazone.

Beneath the Lemon Tree: An Interrupted Family Story

Through an autoethnographic account centered around family recipes, the author, a Mennonite, reflects on her interrupted family story.

Model-based clustering of multi-tissue gene expression data

Motivation Recently, it has become feasible to generate large-scale, multi-tissue gene expression data, where expression profiles are obtained from multiple tissues or organs sampled from dozens to hundreds of individuals. When traditional clustering methods are applied to this type of data, important information is lost, because they either require all tissues to be analyzed independently, ignoring dependencies and similarities between tissues, or to merge tissues in a single, monolithic dataset, ignoring individual characteristics of tissues. Results We developed a Bayesian model-based multi-tissue clustering algorithm, revamp, which can incorporate prior information on physiological tissue similarity, and which results in a set of clusters, each consisting of a core set of genes conserved across tissues as well as differential sets of genes specific to one or more subsets of tissues. Using data from seven vascular and metabolic tissues from over 100 individuals in the STockholm Atherosclerosis Gene Expression (STAGE) study, we demonstrate that multi-tissue clusters inferred by revamp are more enriched for tissue-dependent protein-protein interactions compared to alternative approaches. We further demonstrate that revamp results in easily interpretable multi-tissue gene expression associations to key coronary artery disease processes and clinical phenotypes in the STAGE individuals. Availability and implementation Revamp is implemented in the Lemon-Tree software, available at https://github.com/eb00/lemon-tree Supplementary information Supplementary data are available at Bioinformatics online.

Emergence Percentage and Speed of Rootstocks for Citriculture in South of Brazil

The fact that Brazilian citriculture has focused on few rootstocks poses several phytosanitary risks to the culture and has made genetic improvement programs develop hybrid genotypes to be used as novel alternatives. This study aimed at evaluating the behavior of 42 different rootstocks regarding their emergence percentage and speed in weather conditions experienced in the extreme south of Brazil. Seeds of hybrids developed by the Citrus Genetic Improvement Program (PMG Citros) at the Embrapa Mandioca e Fruticultura (PMG Citros) and cultivars from other citrus growing regions were sown in conical tubes filled with commercial substrate in May 2017. A thoroughly randomized design with 4 replicates, each composed of 45 sampling units, was employed. Emergence percentage and emergence speed of every genotype were evaluated and the ones with the highest emergence percentage of seedlings and the ones with the most precocious emergence were identified. All genotypes completed seedling emergence 98 days after sowing. Seeds of Trifoliata, TSKC × CTSW-041 and TSKC × CTSW-025 had the highest values of seedling emergence whereas the highest emergence speed indexes were exhibited by genotypes Trifoliata and lemon tree ‘Cravo’.