Karyotype and genome size determination of Jarilla chocola, an additional sister clade of Carica papaya

Jarilla chocola is an herbaceous plant species that belongs to the Jarilla genus and the Caricaceae family. No information on chromosome number or genome size has been reported for J. chocola that confirms the occurrence of dysploidy events and explore the existence of heteromorphic sex chromosomes. Therefore, the total number of chromosomes of this species was determined by karyotyping and counting the number of chromosomes observed, and the genome size of female and male plants was estimated separately by flow cytometry. Results showed that J. chocola has eight pairs of chromosomes (2n = 2x = 16), and its chromosomes are classified as metacentric for five pairs, submetacentric for two pairs and telocentric for one pair. The nuclear DNA content (1C-value) in picograms and diploid genome size was estimated separately from female and male plants using two species as the standards, Phaseolus vulgaris (1C = 0.60 pg) and Carica papaya (1C = 0.325 pg), to look for the possible existence of heteromorphic sex chromosomes. C. papaya proved to be a better standard for the determination of J. chocola DNA content and diploid genome size. No significant difference on the DNA content was observed between female (1C = 1.02 ± 0.003 pg) and male (1C = 1.02 ± 0.008 pg) plants. The estimated genome size of J. chocola per haploid genome in base pairs was calculated from the obtained C-values. Results showed an estimated genome size per haploid genome of 1018.44 ± 3.07 Mb and 1022.08 ± 7.76 Mb for female and male plants, respectively. Due to the observed chromosome number and genome size, only the occurrence of one of two previously reported dysploidy events in Jarilla could be confirmed for J. chocola and no evidence of heteromorphic sex chromosomes was found. These results provide fundamental information of the J. chocola genome and will expedite investigation of sex chromosomes and genome evolution in this species, the Jarilla genus and the Caricaceae family

Root proteome alterations in sugarcane promoted by the regrowth cycle in commercial production

The decrease in agricultural productivity in successive cutting of sugarcane plants is associated with several extrinsic and intrinsic factors. However, no studies have focused on the physiological potential of sett roots in successive cuts in sugarcane culture. There have been no proteomic studies on sugarcane sett roots at different stages of cutting. In this study, the UPLC-ESI-TOF-MS system and bioinformatics tools were used to identify proteins of sett roots in the first and fifth cuts of sugarcane cultivar RB966928 in the sprouting stage. Differences in the proteome of sett roots of RB966928 in the first and fifth cuts detected in this study supports the hypothesis that the proteome of sett roots may change after successive cuts in sugarcane culture. A reduction in the number of proteins was observed in the roots of the fifth cut, whereas 34% of proteins, identified exclusively in the first cut, were absent in the fifth cut. Proteome analysis of sett roots in the first and fifth cuts showed that the changes after successive cuts were quantitative (number of proteins) and mainly qualitative. In this study, the detailed list of proteins identified in the first cut but absent in the fifth cut is relevant. The findings of this study may aid further research that employ biotic or abiotic elicitors to induce gene expression of essential proteins absent in sett roots of the fifth cut, and thus increasing the agricultural productivity and longevity of cane fields

Quality of soybean seeds submitted to different treatments and storage conditions

Chemical seed treatment is a recommended technique to protect seeds from pathogens that can affect their quality. The objective of this work was to analyse the quality of soybean seeds with different treatments under different storage temperatures. Seeds of cultivar ‘M 8378 IPRO’ produced in Mato Grosso, Brazil were used. A completely randomised design was used in a 4 × 3 two-factorial scheme. The seeds were treated with three different combinations of chemicals (fungicides, insecticides, polymer and drying powder) in addition to the control (untreated seeds) combined with three different storage temperatures (13 °C, 19 °C and uncontrolled temperature), with three repetitions. Quality was assessed by the germination test (TG), accelerated aging (AA), field emergence (FE), tetrazolium test (TZ) and isoenzyme analysis. The uncontrolled storage temperature negatively influenced the variables germination, accelerated aging and field emergence. The vigour and viability of the tetrazolium test showed that untreated seeds had better physiological quality than seeds with chemical treatment. The expression of isoenzymes showed a difference between treatments. Even with the stress caused by the seed treatment, this tool is very important for the initial protection of the seedlings.

De novo transcriptome sequencing, assembly and characterization of Heliopsis longipes roots vs. leaves to discover putative genes involved in specialized metabolites biosynthesis

Heliopsis longipes is a valuable source of specialized metabolites (or secondary metabolites) with medicinal properties mainly in roots. However, little is known about genes involved in the biosynthesis of these metabolites, primarily due to the lack of genome or transcriptome resources. In this work, the genes of the biosynthetic pathway of the specialized metabolism from H. longipes roots and leaves through de novo RNA sequencing (RNA-Seq) using the platform of Illumina paired-end sequencing were studied. After de novo transcriptome assembly using the software Newbler, a total of 172,342 non-redundant transcripts with an N50 value of 816 bp was obtained. Further functional classification and annotation with Gene Ontology (GO), BLAST2GO, Kyoto Encyclopedia of Genes and Genome (KEGG), and KEGG automatic annotation server (KAAS), revealed that active genes in tissues are predominately involved in the metabolic process and biosynthesis of specialized metabolite pathways. Differential expression analysis of roots vs. leaves using Cuffdiff software (p-value ≤0.05 and log-fold change ratio (log2) ≥1) revealed that differentially expressed genes (DEGs) were in an organ-specific manner, such as in leaf, DEGs were significantly enriched in photosynthesis, while in roots, were a higher enriched function of plant hormone signal transduction. A total of 63 transcripts DEGs were related to 9 specialized metabolites pathways, in roots the most abundant was the phenylpropanoid biosynthesis, and in leaves was the carotenoids biosynthesis. Several regulatory genes including the basic-helix-loop-helix and basic leucine zipper domain, transcriptions factor families involved in the regulation of phenylpropanoids and carotenoid biosynthesis, respectively, were discovered. This study established a global transcriptome dataset for H. longipes. Data shall be useful to study the functional genomics or genetic engineering of this specie. These results will promote the understanding of the genetic mechanism involved in the biosynthesis of specialized metabolites in H. longipes

MtNOOT gene enhanced high productivity and economical characteristics of tomato (Lycopersicon esculentum)

Tomato (Lycopersicon esculentum) is the main vegetal crop that has tremendous popularity around the world. Medicago truncatula NOOT gene (Mt-NOOT) encodes a BTB/POZ-ankyrin repeat protein of the NONEXPRESSOR OF PR GENES1 (NPR1 family). It was introduced into Lycopersicon esculentum (Tomato) genome. The tomato plants that ectopically expressed Mt-NOOT obtained several favorable traits and fruit quality. Heteroblasty between the transgenic and the non-transgenic tomato leaves and flower architecture were used to distinguish transgenic and wild lines. Transgenic tomato plants accumulated a significant amount of phenolic compounds and plant pigmentations compared to the wild type. On the other hand, transgenic plants acquired a considerable amount of antioxidant such as CuZnSO superoxide dismutase (SOD), tomato Catalase (CAT), and tomato Cell wall-associated peroxidase (TPX1) than the wild type. Antioxidant high content together with the high content of phenolic compounds enabled the transgenic tomato fruits to gain not only edible benefits, but also a significant higher shelf-time, extended to six months more than the wild type stored at 25°C in dark and dry condition. Surprisingly, transgenic tomato fruits did not show any rotten process during long time storage as they did not acquire any contagious microorganism. Total fruit productivity in transgenic tomato was greater than the control with an estimated ratio of 84%.

Pre-emergence herbicidal activity and persistence of 2,4-di-tertbutylphenol in relation to soil types

Although 2,4-di-tert-butylphenol (2,4-DTBP) has demonstrated strong phytotoxic effect on various weedy plants in previous findings, research on its pre-emergence herbicidal activity in the soil is still scanty. The aim of this study was to investigate the effects of two soil types on pre-emergence herbicidal activity and persistence of 2,4-DTBP. The bioassay was carried out in a growth chamber where goosegrass [Eleusine indica (L.) Gaertn.] seeds were sown in different rates of 2,4-DTBP in two soil series under sterilized and non-sterilized soil conditions. Bioassays of each treatment were conducted in four replicates and arranged in completely randomized design. 2,4-DTBP exhibited potent pre-emergence activity as a root inhibitor where it completely inhibited (100% inhibition) of the root growth of E. indica in sandy loam soil at an application rate of 6.14 kg ai/ha. 2,4-DTBP was rapidly detoxified in silt loam soil as a result of high microbial activity where it completely lost its phytotoxicity by giving 100% emergence within 10 weeks even it was applied at an application as high as 20.4 kg ai/ha. However, 2,4-DTBP remained highly phytotoxic in sandy loam soil where it reduced the root and shoot growth by 47 and 36%, respectively, throughout 10 weeks duration of the investigation. The presence of microbes in non-sterilized soil further suggest that soil microbes may modify the chemical structure of the 2,4-DTBP, which in turn decreased its toxicity. The high level of pre-emergence herbicidal activity in conjunction with its biodegradation in silt loam soil imply that 2,4-DTBP may have potential for development as a natural-soil applied herbicide

Molecular characterization of new Buffelgrass (Cenchrus ciliaris) genotypes

Buffelgrass (Cenchrus ciliaris L. Link) is an African agamospermous grass that has been widely introduced into arid regions of the world to improve rangelands for cattle production and as a result, it has invaded adjacent habitats. Cenchrus ciliaris is apomictic, a condition that is normally associated with low genetic variation within populations, but even moderate levels of genetic variation among populations could account for differences in invasiveness. We used Inter-Simple Sequence Repeat markers (ISSRs) to examine genetic variation among buffelgrass genotypes collected from nine different locations in the central region of Saudi Arabia, and three introduced cultivars. The genetic similarity coefficients among the twelve buffelgrass genotypes ranged from 0.66 to 0.94. Maximum similarity was observed between local populations. Introduced cultivars 'Biloela', 'Gayndah' and 'USA' were quite distinct from local populations. The dendogram constructed with UPGMA analysis revealed three clusters. In general, the study revealed the presence of considerable genetic diversity that could be used for further analysis for specific traits of interest.

The variation of volatile compounds emitted from aromatic orchid (Phalaenopsis bellina) at different timing and flowering stages

Phalaenopsis bellina, is an orchid widely known for their distinctive fragrance. Of late, fragrant orchids are getting more attention from Orchid breeders for their horticultural market value. Although volatile compounds have been identified in several orchid species, the floral scent emission of P. bellina is far from understood. Therefore, this study was carried out to investigate the influence of different timing and floral development stages on the volatile emissions from P. bellina flowers using Solid Phase Micro Extraction (SPME) and Gas Chromatography-Mass Spectrometry (GC-MS). The volatile compound was extracted during morning and afternoon sessions from three different floral developmental stages. The volatile compounds emitted from flowers from two different sessions were trapped with SPME fiber for 30 minutes before directly injected into GC-MS for identification. Results showed that approximately 79 volatile compounds were identified, with the terpenoid presented as the major compound class. P. bellina had the highest number of volatiles during the morning and full bloom (41), with 29.82% monoterpene and 23.33% sesquiterpenes accounted in total. α-farnesene (19.56%) was abundance during morning emission and remains as the highest volatile in afternoon emission (44.08%), even higher when compared to morning emission. However, a decrease in the volatile compound was observed in afternoon emission, in which only 34 volatile compounds detected. Meanwhile, partial bloom developmental stage revealed linalool as the major terpenoid volatile compounds (25.89%), with only 20 volatile compounds recorded. On the other hand, no volatile compounds were recorded and profiled from flower bud stage. The establishment of a floral scent study provides a brief overview of the regulation of fragrance in P. bellina, which can be continued through gene isolation or fragrance-related enzymes study. This information will provide necessary information on orchid floral scent research that useful in boosting horticultural trade of the scented orchids and their function in pollination ecology study