Investigation of Growth Characteristics and Phenological Stages of Papaver dubium L. and Papaver rhoeas L. Species Based on Growth Degree Day

Introduction  Plant development is defined as a series of phenological events that are controlled by external factors and determine changes in the shape or function of some organs. Temperature and photoperiod are two of the most important environmental factors affecting phenological development. Papaver rhoeas L. and Papaver dubium L., from the Papaveraceae family, are common annual winter weeds in northern Iran. The life cycle of these species is closely related to winter crops such as wheat (Triticum aestivum L.) and other winter cereals that compete severely with them. The Papaver species are capable of producing a huge amount of small-sized seeds that remain dormant at maturity. The timing of emergence, growth and sexual reproduction is highly important for the success of invasive weeds. Checking the phonological behavior of these plant species along with their seed production would be useful for decision-support systems helping managers select the best management strategies and, thereby, improving P. rhoeas and P. dubium control. Also, the phenology data would allow predicting these species invasibility of new areas. The present study was aimed to quantify the phonological behavior of these weeds. Materials and Methods  In the present study, the phenology of P. rhoeas and P. dubium were studied in the research field at Agricultural Sciences and Natural Resources University of Sari, Iran, with an annual rainfall of 851 mm per year. Seeds of these species were collected from a wheat field located in Mazandaran province, north of Iran during spring 2018. These species seeds were cultivated on 12 November 2018. The phenological stages were recorded from emergence to the end of the seeding stage. The phenology was studied based on the growing degree day. At the end of the experiment, the period of each phenological stage was calculated based on the day and the growing degree day. In order to determine the morphological traits of the plant, eight sampling steps were performed. Morphological traits such as plant height, number of leaves, number of flowers, number of capsules, and dry matter were measured. Results and Discussion  The results showed that P. rhoeas and P. dubium grow from 0 to 1723.56 and 1759.06 growth degrees day, respectively. During this period, seven phenological stages were recorded for these two species. These stages were included emergence, rosette (7-8 leaves), stem elongation and branching, blooming, flowering, fruiting, and seed maturity. The flowering stage period in both species was long, 48 days in P. dubium and 46 days in P. rhoeas. The results showed that the shortest and longest stages of development of these two weeds were emergence and stem elongation, respectively. In this study, the growth period of P. rhoeas and P. dubium took about eight months. It has some variation with regard to height, the number of flower, number of capsule and dry matter between both species under the same environmental conditions but both plants started their developmental stages at the same time and finished at almost the same rate. The trend of changes in height, number of leaves, number of flowers, number of capsules, and dry matter were similar in both species. The life cycle of these two species begins with germination in autumn and ends with seed production in late June. The longest period of growth stage in both species was in spring and this trend decreases in late spring. The flowering stage begins in late March and ends in mid-June. The maturity period of these two species was from mid-June to the end of the first decade of July. One of the characteristics of these two species is high seed production. In P. rhoeas, at the end of the fruiting stage, each plant produced an average of 13 capsules and each plant produced an average of 5000 seeds. Also, in P. dubium, each plant produced an average of 14 capsules, and each plant of this species produces an average of 5922 seeds. Conclusion  Based on knowledge of the different phenological stages of the two species, it is possible to plan for proper management. From a managerial point of view, these two species should be controlled before the blooming stage; so that their seeds do not enter the seed bank, because their seeds are considered as causes of contamination in the field

P3412Risk factors, biomarkers and framingham risk estimate fail to identify presence of subclinical atherosclerosis in young individual with family history of premature coronary artery disease

Abstract Introduction Patients with family history of premature coronary artery disease (CAD) are at increased risk of CAD events at a younger age. Risk factor based approaches and clinical evaluation are most commonly used to assess these individuals. However, it has been recently shown that up to 50% of individual presenting with their first myocardial infarction (MI) were considered to be “low risk” prior to that event. MI is often a result of plaque rupture preceded by progression of subclinical atherosclerosis. Detection of subclinical atherosclerosis may therefore help target prevention of plaque progression. We assessed the value of clinical risk factor, biomarkers and Framingham Risk Score (FRS) in predicting subclinical atherosclerosis in individuals with a family history of premature CAD. Methods From 310 referrals, 222 individuals between the ages of 35 and 55 with a family history of premature CAD (CAD events in first-degree family members (male &lt;55, female &lt;65)) were enrolled for evaluation of risk of CAD. Those with familial hypercholesteremia (possible, probable or definite) were excluded. Patients underwent clinical and risk factor evaluations as well as Cardiac CT or Calcium Score (CS) to assess presence of subclinical / clinical atherosclerosis at the discretion of the treating physician. Results In this pilot, 141 individuals (59% male, mean age 45.9±6.0 years) completed evaluation, and 65 (46%) had evidence of subclinical atherosclerosis on CT coronary angiography or CT calcium score with a mean segment involvement score (SIS) of 2.8 and mean CS of 152, putting them above the 80th percentile for their age and sex. Aside from male sex, age, and smoking history, other traditional risk factors and biomarkers including diabetes mellitus, hypertension, total cholesterol, LDL-C, HDL-C and Cholesterol/HDL-C were not significantly different between those with or without subclinical atherosclerosis (Table 1). Table 1 Conclusion In young individuals with a family history of premature CAD, risk factors, biomarkers, and FRS failed to identify individuals with premature, subclinical atherosclerosis in this pilot study. Detection of subclinical atherosclerosis and early implementation of treatment with the aim of stabilizing plaques and stopping progression might prove vital in reducing events in these individuals. Further studies are warranted. </jats:sec

P3432Coronary artery calcium score is of limited sensitivity in detecting subclinical atherosclerosis in young individuals with family history of coronary artery disease

Abstract Introduction Family history of premature coronary artery disease (CAD) is known to predispose individuals to adverse CAD events, often at a younger age. Current risk stratification strategy is suboptimal, as up to 50% of individuals were considered “low-risk” prior to their first presentation of myocardial infarction. Coronary artery calcium score (CACS) is a marker of atherosclerosis and provides incremental value in risk stratification. However, the utility of CACS may be limited in younger patients as they often have non-calcified atherosclerotic plaques. In this study, we evaluate the sensitivity of CACS in detecting subclinical atherosclerosis in different age groups. Method From 310 referrals to a specialized unit in the management of early atherosclerosis, 222 individuals with a family history of premature CAD (defined as CAD events in first-degree family members, male&lt;55 and female&lt;65) and aged between 35 and 55 were enrolled for assessment of their CAD risks. Individuals with possible, probably or definite familial hypercholesterolemia were excluded. In addition to clinical and risk factor evaluation, cardiac CT and CACS were performed in select individuals, at the discretion of the treating physician. Results Of the 141 (59% male, mean age 45.9±6.0 year) individuals that completed clinical evaluation, 65 (73% male, mean age 47.4±6.9 years) have subclinical atherosclerosis (defined by the presence of atherosclerotic plaques in any of the coronary artery segments in cardiac CT). Of them, 52 have CACS&gt;0, giving an overall sensitivity of 80%. The breakdown by age group is shown in table 1. The sensitivity of CACS in detecting subclinical atherosclerosis is quite modest in younger individuals (60% in individuals &lt;45 year-old) but improves with patient age (&gt;85% in &gt;45 years). Table 1. Sensitivity of CACS in different age groups Age group True Positive Fast Negative Sensitivity N (CAC+ CTCA+) (CAC+ CTCA−) (%) &lt;40 6 4 60 10 41–45 7 4 55 11 46–50 19 3 86 22 51–55 20 1 95 21 Conclusion In younger individuals (&lt;45 years) with family history of premature CAD, CACS is of limited sensitivity in detecting subclinical atherosclerosis, and should not be used to rule out CAD. Further studies are warranted. </jats:sec