By definition a spikelet consists of two glumes and one or more florets. Comments. The bran, embryo and other miscellaneous by-products make up about 10% of the original rough rice weight.The embryo is also called the "germ" because it is the part of the seed that germinates or produces a new plant if the seed is planted rather than milled for consumption. In general, the fertility and kernel weight of inferior spikelets of rice (Oryza Sativa L.) are obviously lower than those of superior spikelets, especially under abiotic stress. In rice there is a single floret represented here by the lemma, palea and grain. (2008) observed that rice pollen germinated on the stigma within 2 min of pollination, and the tube reached Rice is a staple food crop and the threshold temperature for its pollination is 35 °C. The insect attacks during spikelet stage of rice crop. All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. Shi et al. (2015) found a significant negative relationship between spikelet tissue temperature and spikelet … Rice production has also intensified in rainfed-lowland and dryland (upland) cropping systems, many of which are prone to drought and high temperature (Coffman, 1977). ). The small structures labeled "glumes" are rudimentary structures sometimes called bracts instead of glumes. 225-578-4143 Evaluation of Awn Length. The _spikelets_ are rather small, narrow, greenish or purplish, 1/15 inch long or less, the rachilla is slender, produced to about half the length of the spikelet behind the palea. Sorghum: Specialty Types. It is usually interpreted as a bract but it has also been interpreted as one remnant (the abaxial) of the three members of outer perianth whorl (the palea may represent the other two members, having been joined together). During the reproductive period in rice, salinity causes morphological variations similar to other environmental stresses, which cause inhibition of the growth of plant structures, such as the degeneration of primary, secondary and panicle spikelets (CUI et al., 1995). The number of rice spikelets per square meter (S) is often positively correlated with the yield of rice (Evans, 1993) and is the most important component of grain yield (Yoshida, 1981). Global warming is rising as a serious concern affecting agricultural production worldwide. Despite worldwide production increased due to improved varieties and agronomy, it is stagnating since about 10 years in many regions (Ray et al., 2013). African Rice. The reproductive stage of rice is the most sensitive to heat stress, which can lead to spikelet sterility. Elucidating the factors that 2009;Jagadish et al. Asian urban centers hold the majority of the world’s urban poor and, within the next 25 years, nearly 55% of the population of Asia will be located in these areas. The hulls make up about 20% of the rough rice weight. But under two water condition, the selection efficiencies were lower (relative efficiency 0.44 to -0.02) based on Pn at early filling stage, the flowering period, plant height, NP, number of panicles per plant; NGP, number of grains per panicle; NSP, number of, After several branches are produced, the IM switches and generates axillary meristems that produce one, The test cross nursery was raised and observations were recorded on agronomical traits of interest and also on pollen and, Rice straw mulching in aerobic rice improved, The modes of damage to wheat crop were, loopering of tops of wheat plant, poor pollination/fertilization, shattering of, Dictionary, Encyclopedia and Thesaurus - The Free Dictionary, the webmaster's page for free fun content, QUANTITATIVE AND QUALITATIVE RESPONSE OF WHEAT TO PSEUDOMONAS FLUORESCENS RHIZOBACTERIA APPLICATION, Rice Seed Production Under Conditions of Salinity Stres/Producao de sementes de arroz em condicoes de estresse por salinidade, IMPACT OF FOLIAR APPLICATION OF MICRO-NUTRIENTS FERTILIZERS (SUPER DAWN) ON THE GROWTH AND YIELD OF TWO WHEAT (Triticum aestivum L.) VARIETIES, EFFECT OF SEEDING RATE AND SEED SOAKING DURATION ON PRODUCTIVITY OF RELAY - INTERCROPPED WHEAT IN COTTON, Genetic Correlation Analysis of Photosynthetic Characteristics, Yield and Drought Resistance in Spring Wheat (Triticum aestivum), Detection of QTLs for Yield Heterosis in Rice Using a RIL Population and Its Testcross Population, Homogenization and truncation processes in inflorescences of Cyperaceae, Marker assisted development of effective fertility restorers suitable for use in temperate three-line hybrids, Comparison on the effects of mulching and fertilizer treatments on the yield components of aerobic rice MRQ74, Climate variability - a major cause of low yield of Wheat. Because rice has no well-developed glumes, the spikelet and floret are basically the same unit.The first step in milling rice is to remove the hulls - the lemma, palea and glumes. Reduction or elimination of spikelet degeneration to increase spikelet number is critical in increasing the grain yield of cereals. Altmetric Badge. The outer protective structures are called the hulls. 2019, 2018; Zhang et al. Chen et al. Both nymphs and adults suck the content out of grains from pre-flowering spikelets to soft dough stage. However, different responses to heat stress are seemed to show between the superior and inferior spikelet, and this response is scarcely documented that the intrinsic factors remain elusive. Rice (O. sativa and O. glaberrima) is one of the world's most important crops, particularly in Asia, but increasingly so in Africa and Latin America as well. Similarly, Africa’s i… Rice is a key tropical staple food crop and demand for rice is projected to increase as populations continue to grow in Asia and as rice consumption increases rapidly in Sub‐Saharan Africa (Global Rice Science Partnership, 2013).The impacts of climate change are increasingly evident and extreme weather events around the world increasingly threaten food security. The spikelet is an inflorescence structure unique to grasses. The endosperm is mostly carbohydrates. The inflorscence is the arrangement of flowers on a plant and, even though the flowers of … To increase yield, rice breeders have traditionally focused on panicle morphology (branch number and length, spikelet density), but have not considered the number of florets in each spikelet. to spikelet temperature and the tolerance of a rice variety to high air-temperature induced spikelet sterility depends directly on the temperature inside the spikelet itself (Weerakoon et al., 2008). This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. high tube growth rate characterize rice cultivars,which main-tain spikelet fertility and seed set in hot or cold temperature stress (Endo et al. Baton Rouge, LA 70803. It is the lowermost of two chaff-like bracts enclosing the grass floret. Rapid population growth and economic development have imposed growing pressure upon increased food production (Zhang 2007), and a rice yield increase of more than 1.2 % per year will be required in the next decade (Normile 2008).At the same time, paddy area has been decreasing because of expanding construction land … High temperature (HT) during the rice-growing season is a major factor limiting rice yield and grain quality in many agricultural regions (Jia et al. Both the urban and rural poor require food at affordable prices and this must come from increased productivity in intensive rice systems, which account for 75% of total rice production. In a sorghum flower, only one spikelet of each pair is fertile. 10. spikelets synonyms, spikelets pronunciation, spikelets translation, English dictionary definition of spikelets. Notably, the spikelet of wild-type rice is determinate and produces only one fertile floret, but “two-florets spikelet” and “three-florets spikelet” mutants have been genetically selected (Ren et al. The typical rice (Oryza sativa) spikelet contains a single fertile floret and produces only one grain; by contrast, Brachypodium distachyon spikelets contain multiple fertile florets and produce several grains. This leads to unfilled, empty and discolored grains. The panicle size, an important agronomic trait that makes valuable contributions to the grain productivity in rice (Oryza sativa L.), mainly depends on the number of spikelets on a panicle [1,2,3,4].The final panicle size depends on the developmental processes of both spikelet differentiation and spikelet degeneration [].The phenomenon of young spikelet degeneration in cereal crops such … Baton Rouge, LA 70803 The growing global demand for rice means that this staple food will have to be produced more intensively in Asia, Africa, Latin America and the Caribbean. Grain yield was examined by breaking the yield into its four yield components: number of panicles, spikelet number/panicle, filled spikelet percentage, and 1000-grain weight. Rice (Oryza sativa) produces an inflorescence belonging to the raceme class, with long branches, generally called ‘panicles’, whereas wheat (Triticum aestivum) and barley (Hordeum vulgare) form inflorescences without branches, called ‘spikes’ (Itoh et al., 2005). Rice is a major world food crop (FAOSTAT, 2012) and breeding for improved yield potential is crucial (IRRI, 2010). Reproductive stage drought stress results in dramatic reduction of spikelet fertility and grain yield of upland rice (Oryza sativa L.). (1875, p. 125) of the rice spikelet ilndicates six bracts, four of whIiel are called glumes. n. A small or secondary spike, characteristic of grasses and sedges, bearing one or more florets and usually subtended by one or two bracts. Rice is extensively grown in irrigated cropping systems, allowing production in the warmer, high radiation post-monsoon and summer months. Yield Components of Rice 3.2.1. In this study, we characterized three allelic recessive mutants in rice ( Oryza sativa ): nonstop glumes 1-1 ( nsg1-1 ), nsg1-2 , and nsg1-3 . The hypothesis investigated here is that spikelet sterility under pre-anthesis drought is triggered by deficient plant water status that inhibits peduncle elongation, panicle exsertion and anther dehiscence. It consists of two glumes and one or more florets. In wild-type rice, one spikelet produces one fertile floret. Schuster (1910) interprets this to mean that there are two bracts (stunted glumnes) below the structures ordiinarily regarded as glulmes, these presumably represented by the cup below the articulation. 1a) (Ikemoto et al. 1b). 2008; Quampah et al. 2017), and the seeds shatter in the mature stage.Therefore, the upper 1st to 5th spikelets on the top primary branch in a panicle were collected in the flowering stage, and their awn lengths were measured (Fig. In this step the area labeled "embryo" is also removed. The phenomenon of young spikelet degeneration in cereal crops such as rice (Oryza sativa L.) occurs frequently and is a serious physiological defect that causes grain yield loss (Tang et al., 2011; Liao et al., 2012; Wang et al., 2018; Zhang et al., 2018). Number of Panicles, Total Number of Spikelets, and Filled Spikelet Percentage. Actual performances are also threatened by yield instability due to increasingly variable … Rice genotype IR55419-04 showed least effect of water stress treatments for 1000 grain weight i.e., 6.28% and 10.44% reduction, spikelet fertility percentage with 19.99% and 40.01% reduction and the paddy yield per plant of 24.97% and 51.35% under one week and two weeks water stress, respectively. If the infestation is severe it may cause yield loss up to 30%. 3.2. See more. In wild rice, awn length varies according to the spikelet position in the panicle (Fig. Introduction. Dingkuhn et al. The mature rice kernel or grain is made up of several parts. 2017c ). Other articles where Spikelet is discussed: Cyperaceae: Characteristic morphological features: …a single flower), forming the spikelet, the basic unit of a sedge inflorescence. 225-578-4161 It often bears a long bristle called an awn, and may be similar in form to the glumes—chaffy bracts at the base of each spikelet. This unit is referred to as a spikelet before grain formation. Rice in this form is called brown rice. Cause. This unit is referred to as a spikelet before grain formation. Overview of attention for article published in Plant & Cell Physiology, January 2005. Spikelets are arranged into inflorescences of variable size and form: from small, tight heads in many genera to panicles, the usual form of the inflorescence; panicles as long as one metre or more can be found in… By definition a spikelet consists of two glumes and one or more florets. Rice Plant Development: from Zygote to Spikelet. Rice is a staple food for more than half of the world’s population. By definition a grass spikelet is the unit of the inflorscence of a grass, a member of the Poaceae or Gramineae family of plants. The spikelet sterility in rice is sensitive to high temperature but, the degree of sensitivity depends upon developmental stages of the spikelet (Zakaria et al. (2015) recently showed that genetic gains in the yield potential of tropical irrigated rice during the past 20–30 years have been marginal. Because rice has no well-developed glumes, the spikelet and floret are basically the same unit. Furthermore, global climate change is likel… Key words: Dry weight, Gibberellic acid, Number of spikelets, Rice, Spikelet degeneration, Spikelet differentiation. Introduction. 2011).In the last few decades, much effort has been made to elucidate the effect of HT on rice yield, and its relation to rice growth and spikelet sterility. https://medical-dictionary.thefreedictionary.com/spikelet, Hassan and Bano, (2015) applied tryptophan combined with Pseudomonas moraviensis and Bacillus cereus to wheat and reported that this application increase number of plants per square meter, spike length, number of, During the reproductive period in rice, salinity causes morphological variations similar to other environmental stresses, which cause inhibition of the growth of plant structures, such as the degeneration of primary, secondary and panicle, For instance, some[10] reported that foliar application with combination of micronutrients (Cu+Fe+Mn+Zn) produced the highest values of plant height (85.03 and 87.17 cm), tillers number m-2, spikes number m-2, spike length, number of, (2007) whom found the substantial increase in. 1 INTRODUCTION. The LSU AgCenter and the LSU College of Agriculture, 101 Efferson Hall Thus, heat-tolerant and heat-susceptible genotypes were used to investigate their differences in terms of phenotypic responses and expression changes of Hsf genes at the pre-flowering stage under heat stress. In cereal crops, the number of florets in a spikelet is an important factor affecting the grain number per panicle and then the grain yield. Lemma is a phytomorphological term referring to a part of the spikelet. Insect. 2011). web@agcenter.lsu.edu, 106 Martin D. Woodin Hall Spikelet definition, a small or secondary spike in grasses; one of the flower clusters, the unit of inflorescence, consisting of two or more flowers and subtended by one or more glumes variously disposed around a common axis. The hulls are made up of two parts; the outer is called the lemma and the inner is the palea. This study characterized a gain-of-function mutant lateral florets 1 (lf1) in rice. In rice there is a single floret represented here by the lemma, palea and grain. 2010;Rang et al. Define spikelets. Because of the oils and other compounds associated with the embryo, brown rice cannot be stored as long as milled rice. After the hulls are removed, the bran layers are removed, producing the familiar milled white rice. About this Attention Score Good Attention Score compared to outputs of the same age (66th percentile) Plants harvested at the high cutting height produced higher grain yield of the second crop because of the larger spikelet number m −2 and better grain filling using abundant leaf area index (LAI) and nonstructural carbohydrate (NSC) in the stubble. The molecular mechanisms underlying spikelet development and evolution are unclear. Rice (Oryza sativa), a model monocotyledonous plant species, is the staple food for most of the global population.Consequently, breeding high‐yielding rice varieties is urgently required to cope with food shortages worldwide. 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