Background The co-inoculation of soybean with Bradyrhizobium and other plant growth-promoting rhizobacteria (PGPR) is considered a promising technology. However, there has been little quantitative analysis of the effects of this technique on yield variables. In this context, the present study aiming to provide a quantification of the effects of the co-inoculation of Bradyrhizobium and PGPR on the soybean crop using a meta-analysis approach. Methods A total of 42 published articles were examined, all of which considered the effects of co-inoculation of PGPR and Bradyrhizobium on the number of nodules, nodule biomass, root biomass, shoot biomass, shoot nitrogen content, and grain yield of soybean. We also determined whether the genus of the PGPR used as co-inoculant, as well as the experimental conditions, altered the effect size of the PGPR. Results The co-inoculation technology resulted in a significant increase in nodule number (11.40%), nodule biomass (6.47%), root biomass (12.84%), and shoot biomass (6.53%). Despite these positive results, no significant increase was observed in shoot nitrogen content and grain yield. The response of the co-inoculation varied according to the PGPR genus used as co-inoculant, as well as with the experimental conditions. In general, the genera Azospirillum, Bacillus, and Pseudomonas were more effective than Serratia. Overall, the observed increments were more pronounced under pot than that of field conditions. Collectively, this study summarize that co-inoculation improves plant development and increases nodulation, which may be important in overcoming nutritional limitations and potential stresses during the plant growth cycle, even though significant increases in grain yield have not been evidenced by this data meta-analysis.

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Water stress is one of the main limiting factors for common bean crops, negatively affecting grain yield and seed quality. Thus, the objective of this study was to evaluate the inheritance of agromorphological and physiological traits related to drought tolerance in order to identify promising combinations. The experiment was carried out in a greenhouse with a partial diallel scheme between three drought-tolerant genotypes (IAPAR 81, BAT 477. and SEA 5), and nine cultivars widely grown in Brazil (BRS Estilo, IAC Alvorada, IPR Campos Gerais, IPR Uirapuru, IPR Nhambu, BRS Esteio, IPR Garça, BRS Radiante, and DRK 18), in a randomized block design with four replicates. The plants were grown in pots with substrate under 80% of pot capacity until they reached the stage R5, when water supply was restricted to 30% for 20 days in the pots under stress treatment. A wide variability for the agromorphological and physiological traits was observed. Water deficit reduced plant performance for most agromorphological traits and altered their physiological metabolism. Additive and non-additive effects are involved in the genetic control of the majority of agromorphological and physiological traits both under water stress and control (well-watered) conditions. The parental genotypes BAT 477 (group I) and IAC Alvorada, IPR Uirapuru, and BRS Esteio (group II) may be included in breeding programs aiming at improving drought tolerance in common bean since they present high positive general combining abilities for agromorphological traits. The crosses IAPAR 81 × IPR Campos Gerais, and SEA 5 × BRS Radiante resulted in the best combinations considering grain yield per plant and total dry biomass, when cultivated under water deficit.

Water deficit is one of the main factors that reduce grain yield. A better understanding of the mechanisms related to this abiotic stress is a key aspect to design and act upon drought tolerance improvement in crop plants. Therefore, the major objective of this study was to investigate four common bean genotypes for drought tolerance and to establish their tolerance mechanisms. The experiment was carried out in a greenhouse, using the completely randomized design in a factorial arrangement (2 9 4), composed by 2 water conditions (well-watered and water deficit) and 4 cultivars, with six replicates per treatment. The four cultivars, two drought-sensitive (IAC Tybatã and BRS Pontal) and two drought-tolerant (IAPAR 81 and BAT 477), were evaluated for some physiological, biochemical and morphoagronomic traits. Drought promoted physiological and metabolic changes in the plants, reflecting on the morphoagronomic traits. Under water deficit, the genotype IAPAR 81 stood out from the others in terms of physiological characters, however, it presented a low efficiency concerning biochemical activities and a significant reduction in the morphoagronomic characters. The cultivar BAT 477 demonstrated to be drought-adapted presenting more efficient biochemical and morphoagronomic adaptions and the genotype BRS Pontal obtained morphoagronomic values similar to BAT 477, thus it may be classified as moderately tolerant to drought.

The burden of the current global challenge involving food security lies in the need to improve crop production. In this regard, biotechnology stands out as an essential tool to generate plants able to cope with pests, diseases, and harsh climatic conditions, and more efficient in the use of natural resources. An advanced approach to create genetic variability in a precise and targeted way, the genome-editing technique CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR associated proteins), has drawn the attention of breeders. The genome editing CRISPR/Cas system relies on a guiding RNA that directs a nuclease to generate a double-strand break (DSB) at a target DNA, activating the cell repair systems and eventually leading to deletions or insertions of nucleotides. Therefore, CRISPR/Cas is a toolbox to achieve many goals, from basic science investigations to the development of crops with improved agronomic traits, with potential to bring innovative solutions to food production. The CRISPR/Cas system has been applied in a large number of plants, including some horticultural species. In this review, we present details of the CRISPR/Cas natural and artificial systems, its possibilities as a biotechnological tool, advantages over other breeding techniques, regulatory issues, and its applicability in horticultural crops, as well as future challenges.

An optimal condition for extraction of soluble sugars from green coffee using water and a validated chromatographic method for its separation and quantification were proposed in this research. An orbital incubator shaker (OIS) and microwave-assisted extraction (MAE) were the 2 techniques used to extract soluble sugars. In such experiments, the variables: sample amount (300, 400, and 500 mg), time (30, 60, and 90 min), and temperature (30, 45, and 60 °C) were tested. The separation of sugars was performed in a chromatographic system (high-performance liquid chromatography refractive index detector [HPLC-RID]), which presented the selectivity for the analytes, a limit of detection of 0.020 g/L, a limit of quantification of 0.0625 g/L, and recovery rates greater than 95%. The repeatability and inter-day precision had low dispersion, RSD < 2.0% and < 3.0%, respectively. Sucrose content ranged from 0.65 to 2.39 g/L using an OIS and from 1.19 to 2.72 g/L by MAE, while glucose and fructose concentration varied from 0.08 to 0.12 g/L using both methods. The OIS technique is preferably indicated for extraction of soluble sugars at the following conditions: 500 mg of grounded green coffee, 90 min, and 60 °C. The proposed method for soluble sugar extraction and quantification may be applied in research laboratories and food industries since it is a low-cost and environment-friendly technique.

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The objective of this study was to determine the genetic diversity among Brazilian carioca common bean (Phaseolus vulgaris L.) cultivars for traits related to nitrogen use efficiency (NUsE). An additional objective was to identify potential parents and promising parental combinations to assist common bean breeding programs in the development of cultivars with improved NUsE. The experiments were carried out at the Experimental Stations of the Instituto de Desenvolvimento Rural do Paraná (IDR-Paraná) in Londrina and Ponta Grossa, Brazil, during the rainy season in 2017. Thirty-nine common bean cultivars were evaluated under high (40 kg N ha −1 ) and low N (0 kg N ha −1 ) applied as top-dressing. The cultivars were genotyped using the genotyping-by-sequencing (GBS) approach with restriction enzyme CviAII. A total of 23,823 single nucleotide polymorphism (SNP) markers were identified throughout the common bean genome. A wide genetic variability was observed for NUsErelated traits under high and low N conditions. In addition, correlations were found between shoot dry biomass and NUsE, N uptake efficiency (NUpE), and N utilization efficiency (NUtE) under low N, indicating the possibility of indirect selection of these traits by the plant shoot dry biomass. Interestingly, the most low-N-tolerant cultivars were not necessarily the most responsive and/or NUsE, suggesting that different morphophysiological mechanisms control these traits. The cultivars that stood out positively in this study can be used as parents in breeding programs aimed at developing cultivars that are adapted to N limitation.