ABSTRACT
As a motivational factor, uniqueness drives individuals to seek and choose unique goods or experiences. The act of wearing masks obscures individuals' facial features and influences their desire for uniqueness. This study aims to explore how wearing masks promotes individual uniqueness- seeking behavior. Three experiments were performed using various product categories (Starbucks coffee cups, sweatshirts, suitcases, and baseball caps) and sample types (college student and adult samples). Experiment results show that wearing masks obscures individuals' facial features and weakens their self- perceived uniqueness, thereby increasing their willingness to actively purchase unique products. This study is the first to examine the effect of wearing masks on individuals' choice of unique products. Practically, the results suggest that customized products can compensate for the lack of self-perceived uniqueness brought about by facial occlusion, thus providing valuable guidance for companies and retailers that offer customized services in formulating and designing marketing strategies.
ABSTRACT
PURPOSE: Rapunzel syndrome is an uncommon condition in children, and its clinical features remain unclear. This study presents the largest single-center series of pediatric cases to date, with the objective of documenting the clinical characteristics and treatment approaches for children with Rapunzel syndrome. METHODS: A retrospective study was conducted in children with Rapunzel syndrome from 2019 to 2023. We recorded age, gender, symptoms, locations of bezoar, complications, and treatment options. RESULTS: Ten patients with Rapunzel syndrome were included. The median age was 9.1 years, with all of whom were female. The most common clinical symptoms were upper abdominal mass (90%), abdominal pain (80%), and nausea and vomiting (50%). Complications occurred in six cases (60%), including small bowel obstruction (20%), severe gastric dilatation (10%), intestinal perforation (10%), choledochodilation (10%), acute pancreatitis with cholecystitis (10%). Preoperative ultrasonography suggested low-echoic foreign bodies continuing to the jejunum or ileocecal region in five cases (50%). Preoperative gastroscopy attempted in four cases (40%) to remove the foreign bodies, all of which failed. All patients underwent surgical treatment, with nine cases undergoing gastric incision foreign body removal, and one case undergoing gastric incision foreign body removal combined with intestinal perforation repair. All patients recovered well. No recurrence was observed during follow-up. CONCLUSION: The accuracy of ultrasound diagnosis in identifying Rapunzel syndrome is high; however, it may lead to misdiagnosis if not complemented with the patient's medical history. Endoscopic presents a heightened treatment risk and a reduced success rate. The condition commonly presents with severe complications, thus making laparotomy a safe and effective option for intervention.
Subject(s)
Bezoars , Tertiary Care Centers , Adolescent , Child , Child, Preschool , Female , Humans , Male , Bezoars/surgery , Bezoars/complications , Bezoars/diagnosis , Bezoars/diagnostic imaging , Retrospective Studies , Stomach/surgery , Stomach/diagnostic imaging , SyndromeABSTRACT
BACKGROUND: Adenomyoma of the small intestine is rare in children and the clinical characteristics is not clear. The study was to document the clinical characteristics and treatment of children with adenomyoma of the small intestine. METHODS: A retrospective study was conducted in children with intestinal adenomyoma from 2010 to 2022. We recorded age, gender, symptoms, location, tumour size and treatment options. RESULTS: Thirteen patients with adenomyoma of the small bowel were included. The median age was 20 months with a male-to-female ratio of 10:3 and more than half of the patients were younger than 2 years old. The mean tumour size was 2.0 cm. The lesion was found accidentally in one patient, and the others presented with symptoms of intussusception. A pathological lead point was found on ultrasound in seven patients. All tumours were located in the ileum, ranging from 24 to 260 cm proximal to the ileocecal valve. The tumour was found in an antimesenteric site in eight patients. Three patients suffered intestinal necrosis, and segmental resection of the ileum was performed. Three patients without intestinal necrosis underwent tumour rection, while intestinal resection and anastomosis were performed in the remaining seven. All patients recovered well except one, who developed intussusception 7 days after surgery; that patient underwent surgery and recovered uneventfully. CONCLUSIONS: Adenomyoma of the small intestine has a male predominance in children and intussusception is a common presentation. The ultrasound feature is a mass of mixed echogenicity containing several small cystic areas. Surgery is the primary treatment option and the procedure should be chosen based on intraoperative findings.
Subject(s)
Adenomyoma , Intestinal Diseases , Intussusception , Humans , Male , Child , Female , Infant , Child, Preschool , Intussusception/diagnostic imaging , Intussusception/etiology , Retrospective Studies , Adenomyoma/diagnosis , Adenomyoma/pathology , Adenomyoma/surgery , Tertiary Care Centers , Intestine, Small/diagnostic imaging , Intestine, Small/surgery , Intestine, Small/pathology , NecrosisABSTRACT
A comparative proteomics analysis was performed to identify the molecular response of a rice cultivar (Oryza sative cv. 'IRRI71331') with high phosphorous (P) uptake efficiency to low P stress. The hydroponically grown rice plants were provided with two levels of P (0.5 mg x L(-1) and 10 mg x L(-1)) supplied in quarter strength Kimura solution, and the root total proteins extracted on the 3rd and 6th day of treatments were separated by two-dimensional gel electrophoresis (2-DE). Comparing with the control (10 mg x L(-1) of P), a total of 29 protein spots under low P stress (0.5 mg x L(-1)) showed differences in their relative abundance, among which, 17 were higher, 11 were lower, and 1 was novel on the 3rd day, and 8 were induced, 19 were suppressed, 1 was disappeared, and 1 had no obvious change on the 6th day. Ten differentially expressed protein spots were identified by MALDI-TOF/MS, and searched in protein databases. According to the putative functions, the identified proteins were classified into four groups, i.e., signal transduction (glycine-rich RNA-binding protein, phosphate starvation response regulator-like), gene expression (putative pre-mRNA splicing factor, putative AAA-metalloprotease), metabolism (adenylosuccinate lyase, serpin, S-adenosylmethionine synthetase, MYB transcription factor-like protein), and ion transport (cation-transporting ATPase, sarcoplasmic reticulum protein). The identified proteins were involved in various physiological responses to enhance stress resistance, such as signal recognition and transduction, RNA cleavage, degradation of denatured protein, and ion transportation and cellular ion balance. The serine protease inhibitor and S-adenosylmethionine synthetase and the MYB transcription factor-like protein, which were the key proteins associated with P deficiency--tolerance of other species, were affected by the same stress for rice. The results indicated that the tolerance to low P stress was controlled by a complex signal transduction and metabolism regulation network in rice root system.
Subject(s)
Oryza/metabolism , Phosphorus/metabolism , Plant Proteins/analysis , Plant Roots/metabolism , Stress, Physiological , Electrophoresis, Gel, Two-Dimensional/methods , Metabolic Networks and Pathways , Oryza/chemistry , Oryza/growth & development , Phosphorus/analysis , Plant Roots/chemistry , Proteomics/methods , Signal TransductionABSTRACT
The allelopathy-competition separation (ACS) based approach was used to explore the biointerference relationship between rice accessions and barnyardgrass exposed to different nitrogen (N) supplies in hydroponics. Rice accession PI312777 exhibited high allelopathic potential to suppress the growth of accompanying weeds, especially when the culture solution had low N content. The non-allelopathic rice Lemont showed an opposite result. Additionally, subtractive hybridization suppression (SSH) was used to construct a forward SSH-cDNA library of PI312777 to investigate gene expression profiles under low N treatment. A total of 35 positive clones from the SSH-cDNA library were sequenced and annotated. According to the function category, 24 genes were classified into five groups related to primary metabolism, phenolic allelochemical synthesis, plant growth/cell cycle regulation, stress response/signal transduction, and protein synthesis/degradation. Among them, two up-regulated genes that encode PAL and cytochrome P450 were selected. Their transcript abundance at low N level was compared further between the allelopathic rice and its counterpart by utilizing real-time quantitative polymerase chain reaction (qRT-PCR). The transcription levels of the two genes increased in both rice accessions when exposed to low N supply, but PI312777 at a higher magnitude than Lemont. At 1, 3, and 7 days of the treatments, the corresponding relative expression levels of PAL were 11.38, 4.83, and 3.57 fold higher in PI312777 root, but there were 1.15, 2.74, and 2.94 fold increases for Lemont, compared with the control plants fed with regular nutrient. The same trend was found for cytochrome P450. These findings suggest that the stronger ability of PI312777 to suppress target weeds, especially in low N nutrient conditions, might be attributed to the stronger activation of the genes that function in de novo synthesis of allelochemicals.
Subject(s)
Gene Expression , Nitrogen/administration & dosage , Oryza/genetics , Base Sequence , DNA Primers , Genes, Plant , Nucleic Acid Hybridization , Polymerase Chain Reaction , Up-RegulationABSTRACT
Based on the determination of dry matter and caloric value, this paper studied the characteristics of energy accumulation and the dynamics of caloric value in the yield-forming process of rice cultivars Shanyou 63 ( three-line hybrid rice) , Liangyou 2186 (two-line hybrid rice) , and IR64 (conventional rice). The results showed that at fully grain-maturing stage, the amount of dry matter in Shanyou 63, Liangyou 2186 and IR64 was 1926. 38 g x m(2), 1933.80 g x m(-2) and 1842.30 g x m(-2), and that of accumulated energy was 31,137.05 kJ x m(-2) 31 060.63 kJ x m(-2) and 30 454.89 kJ x m(-2) , respectively, showing no significant difference among the cultivars. In the process of grain filling, the apparent transformation ratio of energy in Shanyou 63, Liangyou 2186 and IR64 was about 38. 95% , 28. 38% and 32. 66% , respectively, implying that the energy flow in Shanyou 63 and IR 64 was smoother than that in Liangyou 2186, and the output of energy from stem to the sink of grain was blocked in Liangyou 2186. The ratio of energy partitioning to the sink of grain was 53. 03% , 46. 43% and 50. 11% for Shanyou 63, Liangyou 2186 and IR64, respectively, showing the energy partitioning heterosis in three-line hybrid rice Shanyou 63. As for the caloric value, it had no significant difference among the three cultivars, but decreased in the order of leaf> grain > sheath > stem > root, ranging from 16.81-17.25 kJ x g(-1) , 15.89-16.54 kJ x g (-1) 14.33-15.49 kJ x g(-1) , 14.23-15.15 kJ x g , and 11.51-13.25 kJ x g(-1), respectively. It was also shown that there was a significant positive correlation of caloric value with carbon content, chlorophyll a content, and nitrogen content in rice plant, with the determination coefficient R(2) being 0.609, 0.471 and 0.485, respectively.
Subject(s)
Biomass , Energy Metabolism , Oryza/metabolism , Carbon/analysis , Chlorophyll/analysis , Nitrogen/analysis , Oryza/classification , Oryza/growth & developmentABSTRACT
In this paper, allelopathic rice PI312777 (PI) and non-allelopahtic rice Lemont (Le) were grown in the nutrient solution with two levels of phosphorus (P) supply, and their allelopathic effects on Echinochloa crus-galli L. were studied. The results showed that under phosphorous deficiency stress, the inhibitory effect of PI on E. crus-galli root growth had an obvious increase. After growing in the nutrient solution with low P supply (0.5 mg x L(-1)) for 5, 10 and 15 days, the inhibitory rate of PI on E. crus-galli root dry matter increased by 5.64%, 3.89% and 12.13%, respectively, while that of Le did not show the same trend, compared with normal P supply. With low P supply for 5, 10 and 15 days, PI allelopathic effect on the leaf POD activity of E. crus-galli increased by 20.19%, 15.47% and 6.68%, IAAoase activity increased by 18.08%, 17.71% and 12.50%, while NR activity increased by 13.89%, 18.60% and 2.10%, respectively, suggesting that under P deficiency, PI enhanced its allelopathic potential through two pathways, i.e., to increase the weed POD and IAAoase activities to slow down its growth rate, and to decrease the weed NR activity to affect its N uptake.
Subject(s)
Echinochloa/growth & development , Oryza/physiology , Pheromones/physiology , Phosphorus/pharmacology , Oryza/metabolismABSTRACT
In order to explore the bio-interference of allelopathic rice with barnyardgrass under different nitrogen supplies, a new bioassay method, i.e., allelopathy-competition separation based (ACS) approach was recommended in this study. The results indicated that ACS could be successfully used to distinguish the rice allelopathy from its resources competition in rice-weed co-culture system, and to evaluate its response characteristics under different N supplies. The test rice accession PI312777 had a higher ability in interfering target weed barnyardgrass (BYD), represented by its stable and higher ability in resources competition, as well as its increasing allelopathic potential in suppressing companion weed BYD when the N supply decreased in the co-cultured system. The reverse was true in the case of rice accession Lemont, which had a lower allelopathic potential under all N supply levels, and a lower ability in resources competition under normal or rich N supply. But, Lemont had an obviously increased ability in resources competition under lower N supply, which was considered as the result of econiche competition in rice-weed system.
Subject(s)
Echinochloa/growth & development , Nitrogen/analysis , Oryza/growth & development , Pheromones/pharmacology , Soil/analysis , Herbicides/pharmacology , Oryza/chemistryABSTRACT
In order to understand the allelopathic mechanisms of rice on weed, the allelochemical substitutes salicylic acid, p-hydroxybenzonic acid, cinnamic acid, vanillic acid and ferulic acid were used in an orthogonally gyrating regression experiment to study their interactive effects on the growth of barnyardgrass. The results indicated that whether the interactive effects between two substitutes, e.g., between salicylic and cinnamic acid or between salicylic and p-hydrobanzonic acid, were synergistic or antagonistic depended on the concentrations of each substitutes in the mixture. In the mixture of salicylic acid and p-hydrobanzonic acid, the effect of salicylic acid was synergistic at < 0.14 mmol.L(-1) but antagonistic at > 0.14 mmol.L(-1), while p-hydrobanzonic acid showed an antagonistic effect at > 0.425 mmol.L(-1). Salicylic acid at all test concentrations exhibited antagonism to cinnamic acid, while cinnamic acid had a synergistic at < 0.14 mmol.L(-1), but an antagonistic effect at >0.14 mmol.L(-1) on alicylic acid. The interactive effects between cinnamic and ferulic acid were all synergistic at test concentrations.
Subject(s)
Cinnamates/chemistry , Hydroxybenzoates/chemistry , Pheromones/chemistry , Salicylic Acid/chemistry , Drug Interactions , Oryza/chemistry , Oryza/growth & development , Poaceae/growth & development , Vanillic Acid/chemistryABSTRACT
In this paper, a strong allelopathic rice variety PI312777 and a weak allelopathic rice variety Lemont were used as test materials, and the root exudates of two rice varieties grown in the media of sand and soil were respectively collected by using circulation system approach. The terpenoids in ether-extracts were detected by GC-MS, and characterized by spectrum database. The results showed that some terpenoids such as limonene oxide, limonene dioxide, carvone oxide, carveol, and cedrol were detected in the ether-extracts. Different rice varieties had the similar kinds of terpenoids, but their existing modes and quantities were different. The differences between different various cultural methods and between rice varieties were further discussed.
Subject(s)
Oryza/chemistry , Oryza/classification , Pheromones/chemistry , Plant Roots/chemistry , Terpenes/analysis , Pheromones/analysis , Plant Extracts/chemistryABSTRACT
Four rice cultivars with different photooxidation-tolerance characteristics during grain-filling stage in early and late seasons were selected to uncover the physiological and biochemical mechanisms of the correlation between rice photooxidation-tolerance and grain quality. The results showed that the parameters mean grain-filling rate (Gmean), time arrived to maximum grain-filling rate (T(max. G)), and 100-grain weight at the maximum grain-filling rate (T(max. G)) were relatively stable for the varieties adaptable to high light intensity, while on the contrary for those sensitive to photooxidation. The ADP glucose pyrophosphorylase and starch synthase activities of the varieties adaptable to high light intensity after grain-filling peaks had a less difference between early and late seasons than those sensitive to photooxidation, and the relative enzyme activities in the varieties adaptable to high light intensity changed coequally in early and late seasons.
Subject(s)
Glucose-1-Phosphate Adenylyltransferase/metabolism , Oryza/enzymology , Starch Synthase/metabolism , Sunlight , Edible Grain/growth & development , Oryza/growth & development , Oxidation-Reduction , SeasonsABSTRACT
In this study, allelopathic rice accession PI312777 seedlings were grown on a paddy soil under near natural condition, and their root exudates were collected by using circulation method, with the solution collected from no seedlings- planted soil as the control. The ether extracts of the root exudates and soil solution were detected by GC-MS, and identified with the mass spectral database of NIST and WILEY Library. The results showed that there were 36 compounds in the rice root exudates, including 9 terpenoids (peak area 10.97%), 8 phenols or quinones (5.87%), 6 esters (10.68%), 3 aldehydes or ketones (1.44%), 4 heterocycles (68.04%), 2 alcohols (1.23%), 2 ethers (0.57%), and 2 others (1.20%). A distinctly similar structure was observed among the terpenoids and among the phenols or quinones. In the soil solution, 39 compounds were detected, and 7 of them were the same of the root exudates. The difference of the compounds in rice root exudates and soil solution, and the possible allelopathic mechanisms of these compounds were discussed in this paper.
Subject(s)
Oryza/chemistry , Pheromones/isolation & purification , Plant Roots/chemistry , Seedlings/chemistry , Terpenes/isolation & purification , Heterocyclic Compounds/isolation & purification , Molecular Structure , Oryza/classification , Oryza/growth & development , Phenols/isolation & purification , Plant Extracts/chemistry , Soil/analysisABSTRACT
By the methods of environmental statistics and corresponding analysis, this paper collected 38 early and late rice grain samples from the middle, southern, northern, western and eastern parts of Fujian Province to detect their Hg, As, Cr, Cd and Pb contents, and to search for the main factors resulting in the difference of rice cropping type in different regions, aiming at further understanding the relationships between heavy metal pollution and rice cropping type. The results showed that among the test heavy metals in grain, Pb had the highest percentage (100%) beyond the standard level, followed by Hg (78.95%), Cd (50.5%) and Cu (2.63%), while As did not surpass the standard level. It therefore could be concluded that Pb and Cd were the main factors resulting in the difference of rice cropping type in different regions. The results also showed that 38 rice grain samples could be clustered into 7 groups, indicating that different rice cropping types would significantly cause different degrees of heavy metal pollution, which suggested that the best way in controlling and preventing rice grain heavy metal pollution could be the approach of combining site-controlling with variety selection, based on the situation of different regions and rice cropping systems.
Subject(s)
Edible Grain/chemistry , Food Contamination/statistics & numerical data , Lead/analysis , Metals, Heavy/analysis , Oryza/chemistry , Cadmium/analysis , China , Environmental Pollution/prevention & control , Mercury/analysisABSTRACT
Random Amplified Polymorphic DNA (RAPD) and Inter-simple Sequence Repeat (ISSR) methods were used to detect the genetic diversity of 57 allelopathic rice accessions which were introduced from 10 countries or areas. A total of 12 RAPD primers and seven ISSR primers were indentified with polymorphism among the entries. For RAPD markers, 85 polymorphic bands were produced, percentage of polymorphic bands (PPB) were 69.4%. For ISSR marker, 34 polymorphic bands were generated, PPB were 53.0%. The result from the clustering analysis by UPGMA indicated that those accessions from the same geographical location were clustered into one group. It was also found that some rice accessions with higher allelopathic potential were clustered together, implying that the genes conferring allelopathy in those rice accessions might be isolocus. However, some rice accessions with different allelopathic potential clustered into the same group performed lower level of generic polymorphism which was attributed to oriented selection for other traits in breeding program. The estimates of correlation coefficient of RAPD and ISSR based on the genetic similarity matrices were significantly correlated.
Subject(s)
Oryza/genetics , Random Amplified Polymorphic DNA Technique/methods , Repetitive Sequences, Nucleic Acid , Genetic Variation , Polymorphism, GeneticABSTRACT
Allelochemical substitutions salicylic acid, p-hydroxybenzonic acid, cinnamic acid, vanillic acid and ferulic acid were tested in a gyrating regression experiment to study the weed-suppressive effect of phenolic acids on the root growth of barnyardgrass. The results showed that cinnamic acid had a significant inhibitory effect, its square item regression coefficient being -6.18; salicylic acid, p-hydroxybenzonic acid and ferulic acid had the same trend of weed-suppressive potential as cinnamic acid, while vanillic acid had a different weed-suppressive effect from the others. The inhibition rate (IR) on the root growth of barnyardgrass reached its highest level (78.5%) when 0.06 mmol x L(-1) salicylic acid, 0.60 mmol x L(-1) p-hydrobenzonic acid, 0.24 mmol x L(-1) cinnamic acid, 0.02 mmol x L(-1) vannillic acid and 0.02 mmol x L(-1) ferullic acid were mixed together to apply.
Subject(s)
Herbicides/pharmacology , Hydroxybenzoates/pharmacology , Pheromones/chemistry , Salicylates/pharmacology , Cinnamates/pharmacology , Oryza/chemistry , Oryza/growth & developmentABSTRACT
In this paper, three bioassay methods, i.e., relay seeding in agar (RSA), relay seeding in silica (RSS) and seeding in rice root-exudation (SRE), were used to test the allelopathic potential of 8 rice cultivars on the target weed barnyardgrass (Echinochloa crusgalli). The results indicated that RSA was the ideal method for the bioassay, showing the highest efficiency in the evaluation of allelopathic potential. RSS and SRE had a lower efficiency than RSA, but these two methods showed the same tendency in evaluating the allelopathic potential of rice. RSA, the considered best bioassay method in this experiment, was used for 57 allelopathic rice germplasm screening, and 5 of them, i.e., Iguape Cateto, PI312777, Azucena, Taichung Native 1 and IAC25 performed the strongest allelopathic potential in the suppression on barnyardgrass.
Subject(s)
Echinochloa/growth & development , Oryza/growth & development , Soil/analysis , Herbicides/pharmacology , Nitrogen/analysis , Oryza/chemistry , Oryza/geneticsABSTRACT
The approach of mRNA differential display (DD) was used to analyze the gene differential expression of rice seedling subjected to lowly enhanced Ultraviolet-B radiation. The results showed that of the eighteen differential fragments, fifteen ones were different in expressional levels, another one was depressed, and the other two, named as RUVB1 and RUVB2 respectively, which could be recovered and re-amplified, were specifically induced. Sequence analysis for RUVB2 through Internet BLAST searching indicated that it was more than 95% identities with three rice ESTs, but very low similarity to others in the GenBank, and was mapped on the OSJNBb0091N21BAC(GenBank accession No.: AC091122) in Oryza sativa L.
Subject(s)
Oryza/radiation effects , Oryza/genetics , Polymerase Chain Reaction , Ultraviolet RaysABSTRACT
The genotypic differences in P uptake efficiency of three rice varieties (IR74, IR71331 and IR71379) were studied under the P-deficiency condition with hydroponics, and their adaptability to low phosphorus stress about physio-biochemical mechanisms was further studied. The results showed that rice genotypes tolerated low P stress resulted from the co-ordination of P uptake efficiency, internal utilization efficiency and its translocation efficiency. The higher P-efficiency type IR74 and the middle type IR71331 had a higher P uptake efficiency. The rice genotype with higher P-efficiency was characterized by higher activity and desirable kinetic parameters of H2 PO4- uptake, showing lower Km and Cmin, but higher Imax values and relative APase activity, small amount of Km and Cmin. Moreover, under low P stress, the activity of RNase was about ten to fifteen times as high as that of the control (CK), but it had little genotypic differences.
Subject(s)
Adaptation, Physiological/genetics , Oryza/genetics , Phosphorus Compounds/metabolism , Acid Phosphatase/metabolism , Adaptation, Physiological/drug effects , Biological Transport/drug effects , Genotype , Kinetics , Oryza/metabolism , Phosphates/metabolism , Phosphorus/deficiency , Phosphorus/metabolism , Phosphorus/pharmacology , Phosphorus Compounds/pharmacology , Ribonucleases/metabolismABSTRACT
Two sets of test materials were derived from diallel cross among nine different types of selected rice varieties (lines). Based on the experimental data at different development stages of early and late rice, the estimation of heterosis and genetic correlation of rice grain weight at some development stages (0-->t) or at some special development phases (t--1-->t) was conducted by using additive-dominant genetic model and developmental genetic model for quantitative traits. The results indicated that the heterosis over mid-parent value based on population mean was not significant at 5% level at the early stages (1-12 d), and turned to positively significant as the development process proceeded in early rice. The heterobeltiosis based on population mean appeared to be small negative during the entire courses of grain filling. The heterosis over mid-parent based on population mean appeared to be positively significant at the early and middle grain filling stages (1-18 d), but became insignificant at the late stages (19-28 d) in late rice. The heterobeltiosis based on population mean appeared to be positively significant at the early grain filling stages (1-12 d), but turned to be significantly negative as the development process proceeded in late rice. It also indicated that the heterosis of grain weight development was beneficial to improve the quality of grain filling in late rice, compared to that in early rice. The genetic correlation between the grain weights per se at different stages and the final grain weight was mainly controlled by dominant effects, and became closer with the development process in the early rice, while by additive effects in the late rice. It's suggested that indirect selection of final grain weight throughout the process of grain filling would be more effective in late rice.
Subject(s)
Edible Grain/anatomy & histology , Environment , Hybrid Vigor , Oryza/growth & development , Oryza/geneticsABSTRACT
This paper introduced the developmental genetics and its molecular ecological basis of high yielding formation of rice in the past decade, and analyzed the advantage and the shortage of comparative physiological approach traditionally used in the research work on crop cultivation. It was emphasized to actively introduce the research contents and its methodology from relative disciplines to deeply understand the scientific issue, and suggested that the key to realize stable and high yielding of rice was to develop a rational cultivation system based on the properties of genetic effects on the traits in different developmental stages by controlling and regulating the traits governed by dominant effect genes and additive effect genes x environment in same direction, which was considered as the main characteristics and the technological innovation of modern crop genetic ecological cultivation science. Finally, the development trend of crop cultivation science shifting to molecular crop cultivation science was predicted and discussed.