Unveiling the sweetness: evaluating yield and quality attributes of early generation sweet corn (Zea mays subsp. sachharata) inbred lines through morphological, biochemical and marker-based approaches

BACKGROUND

Sweet corn is gaining tremendous demand worldwide due to urbanization and changing consumer preferences. However, genetic improvement in this crop is being limited by narrow genetic base and other undesirable agronomic traits that hinder the development of superior cultivars. The main requirement in this direction is the development of potentially promising parental lines. One of the most important strategies in this direction is to develop such lines from hybrid-oriented source germplasm which may provide diverse base material with desirable biochemical and agro-morphological attributes.

METHODS AND RESULTS

The study was undertaken to carry out morphological and biochemical evaluation of 80 early generation inbred lines (S2) of sweet corn that were developed from a cross between two single cross sweet corn hybrids (Mithas and Sugar-75). Moreover, validation of favourable recessive alleles for sugar content was carried out using SSR markers. The 80 sweet corn inbreds evaluated for phenotypic characterization showed wide range of variability with respect to different traits studied. The highest content of total carotenoids was found in the inbred S27 (34 μg g-1) followed by the inbred S65 (31.1 μg g-1). The highest content for total sugars was found in S60 (8.54%) followed by S14 (8.34%). Molecular characterization of 80 inbred lines led to the identification of seven inbreds viz., S21, S28, S47, S48, S49, S53, and S54, carrying the alleles specific to the sugary gene (su1) with respect to the markers umc2061 and bnlg1937. Comparing the results of scatter plot for biochemical and morphological traits, it was revealed that inbreds S9, S23, S27 and S36 contain high levels of total sugars and total carotenoids along with moderate values for amylose and yield attributing traits.

CONCLUSION

The inbred lines identified with desirable biochemical and agro-morphological attributes in the study could be utilized as source of favourable alleles in sweet corn breeding programmes after further validation for disease resistance and other agronomic traits. Consequently, the study will not only enhance the genetic base of sweet corn germplasm but also has the potential to develop high-yielding hybrids with improved quality. The inbreds possessing su1 gene on the basis of umc2061 and bnlg1937 markers were also found to possess high sugar content. This indicates the potential of these lines as desirable candidates for breeding programs aimed at improving sweet corn yield and quality. These findings also demonstrate the effectiveness of the molecular markers in facilitating marker-assisted selection for important traits in sweet corn breeding.

Gene expression of near-isogenic lines (NILs) carrying blast resistance genes Pi9 and Pi54 in the background of rice cultivar Mushk Budji

BACKGROUND

Kashmir valley, India is a homeland to rice landraces like Zag, Nunbeoul, Qadirbeigh, Kawkadur, Kamad, Mushk Budji, etc., generally characterized by short grains, aroma, earliness and cold tolerance. Mushk Budji is a commercially important speciality rice known for its taste and aroma, nonetheless, is extremely vulnerable to blast disease. Through the use of the marker-assisted backcrossing (MABC) approach, a set of 24 Near-isogenic lines (NILs) was created, and the lines with the highest background genome recovery were chosen. The expression analysis was carried out for the component genes and other eight pathway genes related to blast resistance.

RESULTS

The major blast resistance genes Pi9 (from IRBL-9W) and Pi54 (from DHMAS 70Q 164-1b) were incorporated following simultaneous-but-step-wise MABC. The NILs harbouring genes Pi9 + Pi54, Pi9 and Pi54 expressed resistance to isolate (Mo-nwi-kash-32) under controlled and natural field conditions. The loci controlling ETI (effector triggered immunity) included the gene Pi9 and showed 61.18 and 60.27 fold change in relative gene expression in Pi54 + Pi9 and Pi9 carrying NILs against RP Mushk Budji. Pi54 was up regulated and showed 41 and 21 fold change in relative gene expression for NIL-Pi54 + Pi9 and NIL-Pi54, respectively. Among the pathway genes, LOC_Os01g60600 (WRKY 108) recorded 8 and 7.5 fold up regulation in Pi9 and Pi54 NILs.

CONCLUSION

The NILs showed recurrent parent genome recovery (RPG) per cent of 81.67 to 92.54 and were on par in performance to recurrent parent Mushk Budji. The lines were utilized to study the expression of the loci controlling WRKYs, peroxidases and chitinases that confer overall ETI response.

Pregnancy outcome in women with antiphospholipid syndrome on low-dose aspirin and heparin: a retrospective study

This retrospective review of hospital records analysed pregnancy outcome with 2 different treatments for women with recurrent miscarriage diagnosed with antiphospholipid syndrome in the index pregnancy. Of 64 women, 29 had received aspirin and 35 aspirin plus heparin. Pregnancy-induced hypertension, prematurity, intrauterine growth restriction and neonatal death were considered as maternal and fetal complications. There were no significant differences in antenatal and maternal complications between the groups. HOwever, there were significant differences in mean anticardiolipin IgG antibody levels. Aspirin alone or in combination with parin was equally efficacious in women with antiphospholipid syndrome and recurrent miscarriage.

Proliferative and morphogenic changes induced by the coculture of rat uterine and peritoneal cells: a cell culture model for endometriosis

OBJECTIVE

To evaluate the proliferative and morphogenic effects induced by the coculture of uterine and peritoneal cells to establish a cell culture model for endometriosis.

DESIGN

Uterine epithelial and stromal cells and peritoneal mesothelial and subserosal cells were cocultured with homologous cell types, heterologous cell types, or as isolated populations using a bicameral chamber design.

SETTING

Department of Obstetrics and Gynecology at the University of Missouri, Columbia, Missouri.

ANIMALS

Cells isolated and purified from five mature female Sprague Dawley rats of normal reproductive status were used to establish cell cultures.

MAIN OUTCOME MEASURES

Cell proliferation (deoxyribonucleic acid synthesis) was measured by the incorporation of 3H-thymidine, and cell morphology was assessed using inverted phase-contrast microscopy.

RESULTS

Peritoneal mesothelial cells augmented proliferation and induced cellular aggregation of uterine stromal cell monolayers. Peritoneal subserosal cells amplified proliferation and induced an irregular, compacted morphology in uterine epithelial cells. The proliferation and morphology of the two peritoneal cell types was not altered by uterine cell coculture.

CONCLUSIONS

The coculture of uterine and peritoneal cells in bicameral chambers provides a tool to study the paracrine interactions of cells that comprise the endometriotic lesion. The altered proliferation and morphology of the uterine cells may be related to the histologic and biochemical asynchrony observed between uterine endometrium and ectopic endometriotic tissue in vivo and offers insight into possible mechanisms of the histogenesis of endometriosis.

A study of adult orthodontic patients and their treatment

This retrospective epidemiological study was undertaken to assess factors related to adult orthodontic treatment and to identify any associated trends. Case records of all patients (676) aged 18 years or over at the start of active orthodontic treatment at the Eastman Dental Hospital, London were examined. Variables associated with patients and their treatment (age, sex, source of referral, malocclusion, type of appliance, and interdisciplinary treatment including orthognathic surgery) were studied and the data analysed statistically. Findings revealed that the number of adult patients undergoing orthodontic treatment has increased significantly, especially since 1985. The age of the patients treated was also found to increase in recent years. The percentage of female patients (72 per cent) Class III malocclusions (21.6 per cent) and Class III skeletal bases (26.2 per cent) was higher than found in studies on children. Most of the treatments required fixed appliances and over half involved interdisciplinary treatment, with an increase in the percentage of orthognathic surgical cases. Surgery was significantly more common in males (P less than 0.01) and highly significantly associated with Class III malocclusions and skeletal III bases (P less than 0.001). Twenty-five per cent of adult patients were found to have had a previous course of orthodontic treatment though these patients were not significantly different from adult patients presenting for the first course of treatment.

Increments in plasma homovanillic acid concentrations after neuroleptic discontinuation are associated with worsening of schizophrenic symptoms

1. Thirty-two male schizophrenic patients participated in this study. 2. Plasma concentrations of the dopamine metabolite, homovanillic acid (pHVA) were assessed once on neuroleptic medication and twice a week for a maximum of six weeks after its discontinuation. 3. Psychiatric symptomatology was assessed once on neuroleptic medication and once a week for a maximum of six weeks after its discontinuation, using the brief psychiatric rating scale (BPRS). 4. pHVA and total BPRS score increased significantly after discontinuation of neuroleptic as compared to baseline. 5. The magnitude of pHVA and BPRS increments after discontinuation of neuroleptic correlated significantly. 6. Results of this study suggest that worsening of schizophrenic symptoms after discontinuation of neuroleptic treatment is associated with increased pHVA concentrations.

Airborne mold survey--Edmonton

An outdoor airborne mold survey was recently carried out in the Edmonton area revealing some previously unrecognized molds, especially Rhodotorula. Hormodendrum was by far the commonest mold identified and was present all year round. It was also revealing that outdoor molds were quite prevalent in the Edmonton area throughout all seasons of the year but certainly more prevalent in the spring and early summer months. It would seem wise to have outdoor mold surveys done periodically in one's own area of practice when one is using immunotherapy with them.