Comparison of physiological and yield traits between purple- and white-pericarp rice using SLs     

Zhi-Juan Ji  Xiao-Guang Wang  Yu-Xiang Zeng  Liang-Yong Ma  Xi-Ming Li  Bing-Xin Liu  Chang-Deng Yang 《Breeding Science》2012,62(1):71-77

Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind low-yield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (white-pericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice.  相似文献   

Developmental Dynamics and Early Growth Vigour in Rice. I. Relationship Between Development Rate (1/Phyllochron) and Growth     

M. C. Rebolledo  M. Dingkuhn  P. Péré  K. L. McNally  D. Luquet 《Journal of Agronomy and Crop Science》2012,198(5):374-384

Achieving early vigour, that is, rapid dry matter accumulation, is a priority in rice crop improvement, but this trait is complex and not well understood genetically and physiologically. This study tested the hypothesis that the development rate (DR) contributes to early vigour. Two diversity panels were phenotyped during vegetative stage for traits constituting early vigour (shoot dry weight, SDW; relative growth rate, RGR) or contributing to early vigour (tillering, leaf size, DR). The first panel comprised 169 genotypes from all major genetic groups of Oryza sativa and was phenotyped under irrigated upland conditions in the field (Philippines, Exp1). The second panel with 190 genotypes representing the diversity of the tropical japonica group was phenotyped in pots in a greenhouse (Montpellier, France, Exp2). Results from field and pot experiment pointed out that DR, tillering and leaf size were positively correlated with RGR and SDW, although the contribution of leaf size was small. DR was positively correlated with tillering but both were negatively correlated with leaf size. DR vs. RGR correlation was conserved in subsets of genotypes with similar leaf size and tillering, suggesting an effect of DR on RGR independent of the other traits. DR is a promising, still underexploited trait contributing to rice early vigour, requiring further genetic and physiological characterization.  相似文献   

杂草稻对粳稻生长及产量的影响   总被引：4，自引：0，他引：4  

郭勋斌  陈伟民  顾克礼  冯长云  袁秦  余柳青 《杂草科学》2012,30(1):35-38

在同期播种情况下,和粳稻相比,杂草稻出苗时的叶片更肥长、营养生长期的植株更高、分蘖数多达4倍以上。不同生物型杂草稻的落粒性差异较大。杂草稻密度愈高对栽培粳稻的产量影响愈大。  相似文献   

Inhibitory and promotive allelopathy in rice (Oryza sativa L.)   总被引：2，自引：1，他引：2  

Yasutomo Takeuchi  Shun Kawaguchi†  Koichi Yoneyama 《Weed Biology and Management》2001,1(3):147-156

Studies on allelopathic rice, which inhibits the germination and development of weeds such as barnyardgrass ( Echinochloa spp.) and ducksalad [ Heteranthera limosa (Sw.) Wild.], have been strongly conducted in the USA, the Philippines, Japan, Korea, and other countries since the 1980s. Weed-suppressing rice plants can compete with weeds for light and mineral nutrients by their rapid and thick growth characteristics, and probably also by their allelopathic effects. It was suggested that allelopathic properties were inherited from parents. Different screening methods for finding allelopathic rice simply and rapidly have been proposed. In contrast, stimulative allelopathy in rice, which promotes germination of the dormant and dormancy-awakened seeds of Monochoria vaginalis (Burm. f.) Kunth var. vaginalis , has been investigated by the authors since the 1990s. Rice seeds promoted the germination in the dark and in light under submerged conditions. Our experiments suggested that rice seeds, hulls, plants and straw contain stimulative substance(s) that promote seed germination of M. vaginalis .  相似文献   

Phylogenetic analysis based on ITS sequences and conditions affecting the type of conidial germination of Bipolaris oryzae     

M. A. G. Dela Paz  P. H. Goodwin  A. K. Raymundo  E. Y. Ardales  C. M. Vera Cruz 《Plant pathology》2006,55(6):756-765

One taxonomic characteristic of Bipolaris species is the bipolar germination of conidia, but conidia of Bipolaris oryzae , the causal pathogen of brown spot in rice, are regularly observed to show intercalary germination, a characteristic of Drechslera species. The effect of selection, culture media and culture age on type of conidial germination was determined for three brown spot isolates from Cavinti, San Pablo and Palawan in the Philippines, obtained from infected leaves showing typical disease symptoms. Based on the analyses of their ITS1, ITS2 and 5·8S rDNA nucleotide sequences, the local isolates were clearly identified as B. oryzae . Selection for colonies of the three isolates derived from single conidia with either bipolar or intercalary germination had no effect on the number of spores showing bipolar germination in subsequent cultures. Germination on seven different culture media was tested; of these, rabbit food agar and water agar increased the percentage of bipolar germination of conidia, although this varied between isolates. Incubation of the cultures of all three isolates for longer periods prior to harvesting conidia increased the percentage of bipolar-germinating conidia from c . 40 to c . 90% with 5-day-old and 30-day-old cultures, respectively.  相似文献   

Pathogenesis-related gene expression in rice is correlated with developmentally controlled Xa21-mediated resistance against Xanthomonas oryzae pv. oryzae     

Grisel Ponciano  Masayasu Yoshikawa  Jamie L. Lee  Pamela C. Ronald  Maureen C. Whalen   《Physiological and Molecular Plant Pathology》2006,69(4-6):131-139

Disease resistance mediated by the resistance gene Xa21 is developmentally controlled in rice. We examined the relationship between Pathogenesis Related (PR) defense gene expression and Xa21-mediated developmental disease resistance induced by Xanthomonas oryzae pv. oryzae (Xoo). OsPR1a, OsPR1b, and OsPR1c genes were cloned and their induction was analyzed, in addition to the OsPR10a gene, at the juvenile and adult stages in response to a wildtype Xoo strain that induces a resistance response (incompatible interaction) and an isogenic mutant Xoo strain that does not (compatible interaction). We found that the adult stage leaves are more competent to express these OsPR1 genes and that the Xa21 locus is required for the highest levels of induction.  相似文献   

Biotransformation of clomazone in rice (Oryza sativa) and early watergrass (Echinochloa oryzoides)     

P.L. TenBrook 《Pesticide biochemistry and physiology》2006,85(1):38-45

Rice (Oryza sativa), a relatively tolerant species, and early watergrass (Echinochloa oryzoides; EWG), a relatively susceptible species, were exposed to ¹⁴C-labeled clomazone to determine accumulation, biotransformation, and mass balance. On a total mass basis, rice absorbed more clomazone than EWG (p < 0.05), but on a nmol/g basis, there was no significant difference between the two species (p > 0.05). Rice contained more extractable ¹⁴C residues (7.7 ± 0.5 vs. 4.8 ± 0.5 nmol in rice vs. EWG, respectively; p < 0.5), but the concentration in EWG was significantly higher (4.2 ± 0.5 vs. 1.8 ± 0.1 nmol/g in EWG vs. rice, respectively; p < 0.01). More metabolized residue was measured in EWG compared to rice (84.1% vs. 67.9%; p < 0.01). Both species produced hydroxylated forms, β-d-glucoside conjugates, and several other unidentified polar metabolites, but EWG generally produced higher metabolite concentrations. The concentration of the suspected active metabolite, 5-ketoclomazone, was significantly higher in EWG vs. rice (21 ± 2 vs. 5.7 ± 0.5 pmol/g, respectively; p < 0.01). Differences in sensitivity to clomazone between rice and EWG appear to be due to differential metabolism, but in this case the more susceptible EWG qualitatively and quantitatively metabolized more clomazone than the more tolerant rice. This is consistent with the action of a metabolically activated herbicide. This metabolic difference could be exploited to develop herbicide safeners for use with clomazone.  相似文献   

东乡野生稻原产地蜘蛛群落结构动态研究          下载免费PDF全文

袁凤辉  陈连水  范志刚  颜亨梅  饶军 《植物保护》2007,33(6):103-107

调查表明,东乡野生稻原产保护地蜘蛛群落优势科为狼蛛科、跳蛛科、管巢蛛科、球蛛科、肖蛸科,相对丰度分别为0.5010、0.1529、0.0785、0.0657、0.0559、0.0399、0.0392,其丰盛度总和达0.8540,构成了蜘蛛群落的主要成分;巨蟹蛛科为稀有科。优势种为拟水狼蛛、沟渠豹蛛、中华狼蛛、横窝希蛛、黄斑纯蛛、白纹舞蛛、微菱头蛛、柔弱锯螯蛛,其相对丰盛度分别为0.1802、0.1209、0.0833、0.0589、0.0484、0.0445、0.0417、0.0413,丰盛度总和达0.6192,埃比熊蛛等为稀有种。调查还表明,不同时期的物种丰富度变化不明显,但在6～7月间,群落中物种丰富度相对较高,各物种种群发生数量大,分布相对均匀,优势种不突出,群落结构较合理,均匀度和多样性指数较高。  相似文献   

Decomposition of (1–3,1–4)-β-Glucan and Expression of the (1–3,1–4) -β-Glucanase Gene in Rice Stems during Ripening     

《Plant Production Science》2013,16(3):230-234

Abstract

To elucidate the possible participation of hemicellulose decomposition in lodging resistance, we studied the change of hemicellulose and cellulose content in the stems of rice during the ripening stage by methylation analysis and the expression of related genes by Northern blotting. In the rice stem in ripening stage, content of (1-3,1-4)-β-glucan, a component of hemicellulose, decreased markedly although the content of arabinoxylan, a major component of hemicellulose, and cellulose showed little change during the same growth period. On the other hand, expression of the Gns 1 gene, which may encode (1-3,1-4) -β-glucanase that catalyzes the degradation of (1-3,14) -β-glucan, increased sharply in the stem. The mechanism of decomposition of (1-3,1-4) -β-glucan in rice stem and the possible association with lodging resistance is discussed.  相似文献   

Characterizing Submergence Survival Strategy in Rice Via Chlorophyll Fluorescence     

C. Sone  O. Ito  J.‐I. Sakagami 《Journal of Agronomy and Crop Science》2012,198(2):152-160

Rice plants cope with flash floods using either an ‘escape strategy’ involving rapid shoot elongation or a ‘quiescence strategy’ involving survival underwater with minimal activity. To clarify the differences in the response of leaf photosynthesis properties to conditions during and after submergence, two rice cultivars were compared: a non‐shoot‐elongating cultivar IR 67520‐B‐14‐1‐3‐2‐2 (IR67520) and a shoot‐elongating cultivar IR72442‐6B‐3‐2‐1‐1 (IR72442). Twenty‐three‐day‐old seedlings were submerged in 80‐cm‐deep water for 14 days. During submergence, the chlorophyll contents of the upper fully expanded leaf (5th leaf) and newly developed leaf later (6th leaf) and the maximal quantum yield of photosystem II (F_v/F_m) of the fifth leaf decreased earlier in IR72442 than in IR67520. In the submerged sixth leaf, F_v/F_m was higher in IR72442 than in IR67520 at early measurement. Although F_v/F_m of the sixth leaf in submerged IR67520 increased substantially from 2 days post‐submergence, IR72442 decreased because of leaf chlorosis. Therefore, a non‐shoot‐elongating cultivar coped with submergence by inhibiting photodamage and maintaining high chlorophyll content in the leaves. The shoot‐elongating cultivar was able to maintain the photosynthetic capacity of the newly developed leaf during submergence by prompt reduction of chlorophyll and chlorophyll fluorescence in the leaf that developed before submergence.  相似文献