Heterosis in rice pdf file

Dissecting combining ability effect in a rice nciiiii population provides insights into heterosis in indicajaponica cross hao zhou, duo xia, jing zeng, gonghao jiang and yuqing he abstract background. These results are in disagreement with a series of studies on heterosis in rice by y u et al. But as is traditionally known, rice is a slow starter and this is also true to the fact that it took close to two centuries after the voyages of columbus for rice to take root in the americas. Further, the availability of the complete sequences of the two rice genomes gof f et al. However, the molecular basis underlying heterosis in broccoli remains elusive. In this view, the superior performance of the hybrid is attributed to heterozygote combinations that compensate for deleterious mutations accumulating in. Various models have been posited to explain heterosis, including dominance, overdominance, and pseudooverdominance. Understanding genetic variability and mode of gene action for agronomic and yield related traits is important in formulation of effective rice breeding program for genetic enhancement of grain yield. F1, heterobeltiosis, hybrid vigor, oryza sativa, standard heterosis. In india, hybrid rice production mainly depend on cgms system. Advances and prospects of super rice breeding in china.

Heterosis, or hybrid vigour, is the superior performance of hybrids in biomass, resistance, and fertility compared with their parents shull, 1908. In addition, rnaseq has been applied to the identification of stressinducible transcripts in rice 17,21. Heterosis and inheritance of fertilityrestorer genes in rice. It is likely that a common biological mechanism underlying heterosis is existed in a wide variety of different species.

Assessment of heterosis in two arabidopsis thaliana common. Manual for hybrid rice seed production download ebook pdf. After maize hybrid was first utilized in field on a large scale in usa in 1930s, heterosis of other crops such as rice, sorghum, rape, and vegetable etc began to be widely used in production, and had made great achievements in crop breeding by the end of last century, mainly contributed to notable increasing of crop yield. The application of heterosis hybrid vigor in hybrid rice since the 1970s has tremendously improved rice productivity worldwide. In addition to the heterosis of aboveground agronomic traits on which most existing studies have focused, root heterosis is also an indispensable component of heterosis in the entire plant and of major importance to plant breeding. The merging of genomes in interspecific hybrids can result in novel phenotypes, including increased growth rate and biomass yield, a phenomenon known as heterosis. Heterosis for grain yield and its component traits in rice. Small rnas as important regulators for the hybrid vigour of. Studies conducted at the international rice research institute irri during 1980 and 1981 have shown up to 73% heterosis, 59% heterobeltiosis and 34% standard heterosis for yield in rice. These observations tend to implicate epistasis and overdominance, rather than dominance, as the major genetic basis of heterosis in rice. When two homozygous inbreeds a true breeding line obtained by continuous inbreeding of genetically unlike constituents are crossed together, the resulting hybrids obtained from.

Genetic composition of yield heterosis in an elite rice hybrid. The present study was focused on assessment of heterosis and heritability among f 1 rice hybrids for yield and yieldrelated traits. Research article open access transcriptome analysis of rice. For example, transcriptome analysis of rice mature root tissue and root tips at two time points identified 1761 rootenriched transcripts and 306 tipenriched transcripts involved in different physiological processes 15. In this perspective, we consider that it might be useful to the field to abandon these.

The firstgeneration offspring generally show, in greater measure, the desired characteristics of both parents. Heterosis in f 1 rice hybrids article pdf available in acoustics, speech, and signal processing newsletter, ieee 24 january 2007 with 583 reads how we measure reads. Analysis of the agronomic traits of five hybrids, which were developed by crossing autotetraploid rice line t449 with five neotetraploid rice lines, showed significant improvement in important yieldrelated traits, including number of filled grains per plant, yield per plant and seed setting. Yield of f1, f2 and f3 hybrids of rice oryza sativa l. The present investigation was conducted at the rice research and training center rrtc,sakha, kafrelsheikh, egypt, during 2014 and 2015 growing seasons to evaluate some root characters of some rice genotypes for drought and wellwatered conditions. Diallel analysis of combining ability and heterosis for. Global dna methylation analysis, transcriptome analysis and small rna profiling were aimed to understand the epigenetic effect of the changes in gene expression level in the two hybrids and their parental lines. Despite its importance in maize production, we know surprisingly little about the genetic basis of heterosis.

May 11, 2017 the merging of genomes in interspecific hybrids can result in novel phenotypes, including increased growth rate and biomass yield, a phenomenon known as heterosis. However, little information about long panicle associated with heterosis or hybrid vigor is available in neotetraploid rice. Combining ability is a measure for selecting elite parents that make the highest contributions to hybrid performance. Heterosis, also called hybrid vigour, the increase in such characteristics as size, growth rate, fertility, and yield of a hybrid organism over those of its parents.

Heterosis breeding is an important genetic tool that. Heterosis is the superiority of f 1 hybrids over their parents. Means 1 and heterosis percentage compared to parent mean h for eight characteristics evaluated in complete diallel without reciprocals, among six parents of capsicum annuum. Plant and animal breeders exploit heterosis by mating two different purebred lines that have certain desirable traits. Transcriptome analysis of rice root heterosis by rnaseq pdf. The exploitation of hybrid vigour in rice has been focusing on increasing grain yield. Transcriptome and dna methylome reveal insights into yield. Eight genotypes consisting three basmati varieties viz, basmati kasturi, basmati 370 and basmati with five manipur scented rice landraces viz, chakhao poireiton, chakhao, chakhao amubi, ching chakhao and chakhao angangba were crossed in 8x8 diallel fashion without recieprocal producing twenty eight f 1 hybrids and were evaluated to estimate mid parent heterosis for eleven yield contibuting. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of its parents. Determination of heterotic groups and heterosis analysis.

A survey of the occurrence and the degree of heterosis related to rice seedling growth was conducted with the. Heterosis is typically viewed as the opposite of hybrid incompatibility. Heterosis is a common phenomenon in maize, rice and other species 6. Insights into the genomic architecture of heterosis for grain yield in rice are presented, and further mapping of grain yield loci resolves candidate genes that could be useful for breeding. Department of plant breeding and genetics, the university of agriculture, peshawarpakistan 2. Feb 27, 2017 rice is one of the most important staple foods. Hybrid rice therefore has two genetically different parents. Now a large research project coled by the chinese academy of agricultural sciences has dissected the genetic architecture underpinning this hybrid success. Heterosis is used to increase yields, uniformity, and vigor. Advances in hybrid rice technology, proceedings of the 3rd international symposium on hybrid rice 1416 november 1996 hyderabad india. Heterosis, hybrid vigor, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. Rice is one of the most important stable food crops and an excellent model for grass species. Research note exploitation of heterosis in rice oryza. Rice is a selfpollinating crop, even though strong heterosis is observed in their f 1 hybrids.

Dominance of linked factors as a means of accounting for. Singlelocus heterotic effects and dominance by dominance interactions can adequately explain the genetic basis of heterosis in an elite rice hybrid. Here, we conducted a systematic survey of the degree of heterosis in arabidopsis. Polyploidization has played an important role in plant evolution and is a pathway for plants to increase genetic diversification and to get higher heterosis comparing with that of diploid does. In fact, enhanced heterosis greater than 40% observed at irri in indicatropical japonica crosses encouraged us to develop cms lines in the genetic background of elite tj lines possessing wide compatibility wc genes. The differentially expressed genes including the nonadditively. But how breeders construct hybrid parents to obtain hybrid rice heterosis remains unclear. In this study, a small testcrossed rice population was constructed to investigate the formation mechanism of heterosis for traits. Heterosis analysis and underlying molecular regulatory. Significant midparent heterosis was detected for 141 sequences, which demonstrated the following features. Heritability and heterosis for yield and yield related traits. In this study, we analyzed plant height, grain number per panicle, and other yield related traits of hybrid rice liangyoupeijiu lyp9 and its parents peiai 64s and.

The molecular design of the ideal plant architecture with giant panicle and erect superhybrid rice with giant panicle is the direction to be taken in future rice breeding efforts liu et al. As with other types of hybrids, hybrid rice typically displays heterosis or hybrid vigor such that when it is. Rice is the most important crop in nepal accounting for 50% of the. Rice has also become an excellent model system in plant biology research for monocotyledon species because of its many advantages relative to other cereals 12. The f 1 were left to produce f 2 seeds during the 2011. Hybrid vigor is defined by mechanisms such as dominant. Mar 15, 2020 heterosis dan heterobeltiosis pada persilangan 5 genotip cabai dengan metode dialil. Heterotic groups determination and heterosis analysis of yield performance in indica rice 263 lines, was selected from a distancebased cluster generated from 193 pairs of ssr markers wang et al, 2016.

Studies on heterosis and anther culture for doubled haploid production in rice oryza sativa l. Pdf it is important to know the degree and direction of hybrid vigor for its commercial exploitation. Heterosis in internode elongation and plant height are commonly observed in hybrid plants, and higher gas contents were found to be correlated with the heterosis in plant height. In the present study, transcriptome profiles revealed that the hybridization made most genes show additive expression patterns in hybrid broccoli. Altered gene expression caused by interactions between transcription factors and the allelic promoter region in the hybrids was one plausible mechanism for heterosis in rice. Organization of hybrid rice breeding program using cms system. Heterosis or hybrid vigor results in a hybrids phenotypic superiority over its founder parents for quantitative and qualitative traits. Heterosis expression of hybrid rice in natural and shortday. Heterosis refers to the phenomenon that progeny of diverse varieties of a species or crosses between species exhibit greater biomass, speed of development, and fertility than both parents. Corn maize nearly all field corn grown in most developed nations exhibits heterosis. Thereafter the journey of rice continues with the moors taking it to spain in 70 0 a. Heterosis and inheritance of fertilityrestorer genes in rice jakkrit seesang, prapa sripichitt, tanee sreewongchai department of agronomy, faculty of agriculture, kasetsart university, bangkok 10900 thailand corresponding author, email.

To compare the heterosis levels among various groups of parental lines used extensively in china, identify foundational heterotic groups in parental pools and understand the relationship between genetic distance and heterosis performance, 16 parental lines with extensive genetic variation were selected from various subgroups, and 39 hybrid combinations were generated and evaluated in fujian. Genomic architecture of heterosis for yield traits in rice article pdf available in nature 5377622 september 2016 with 2,206 reads how we measure reads. In this article we will discuss about heterosis or hybrid vigour. Heterosis under aerobic condition in hybrid rice core. The latter was estimated in comparison to commercial varieties. Heterosis may also be a combination of genetic and epigenetic regulation. The superhybrid rice parent r1128 is an optimal res. Trends of magnitude of heterosis for grain yield and plant height were ij ii jj and for days to 50%. Determination of heterotic groups and heterosis analysis of. The third experiment estimated the inheritance of fertilityrestorer genes in rice including two f 2 populations, with crosses between ch1 and ch4 new plant type as restorer lines and ir80151a wacms as female parental line.

Transcriptomic analysis reveals overdominance playing a. After the establishment of the breeding theory and strategy of generating an ideotype with strong heterosis through intersubspecies hybridization, by using gene. The extent of heterosis identified in our study is comparable to that from the research by zhang et al. Genetic analysis for the grain number heterosis of a. Assessment of genetic variability, heterosis and heritability for morphological parameters in rice muhammad ismaeel1,2, syed mehar ali shah1, syed suliman1, ahmad raza1 and muhammad anwar2 1.

Pdf for practical exploitation of hybrid vigor in rice, emasculation is a major constraint, however, the use of male sterile lines increases the. However, the molecular basis for the increased internode elongation in hybrids is unknown. Hybrid rice is grown from hybrid rice seed which is produced by growing an inbred rice variety having sterile pollen which is cross pollinated with normal pollen from adjacent rice plants of a different inbred variety. Heterosis in inter and intrasubspecific crosses over three. The principle of heterosis, whereby a hybrid variety outperforms both parents, is commonly exploited in agriculture to maximize crop yield. Heterosis is observed in almost every crop species studied, the application of this phenomenon for its commercial exploitation depends on the expression of the degree of heterosis. Consequently, systematic investigations of root heterosis, particularly in reproductivestage rice. Pdf genomic architecture of heterosis for yield traits.

Cytoplasmic male sterility and the fertility restoration system have been primarily used to develop heterotic rice hybrids in and outside china lin and yuan 1980 and virmani et al. Dissecting combining ability effect in a rice nciiiii. Heterosis for yield and yield components in rice introduction. Curds are the main edible organs, which exhibit remarkable yield heterosis in f1 hybrid broccoli. Heterosis as a consequence of regulatory incompatibility. Hybrid breeding methods are used in maize, sorghum, rice, sugar beet, onion, spinach, sunflowers, broccoli and to create a more psychoactive cannabis. Heterosis is a phenomenon in which hybrids exhibit superior performance relative to parental phenotypes.

First, most qtl associated with inbreeding depression and heterosis in rice appeared to be involved in epistasis. Most of the crosses which exhibited superiority over better parent or standard variety for grain yield also showed significant heterosis for number of fertile spikelets. The analyses displayed a picture that accumulation of small advantages genomewide could explain the genetic basis of heterosis in this elite rice hybrid. Since then, heterosis is a major concern for both biologists and breeders. Here, by genome analysis, we found that breeders introduced different introgressed exogenous genomes of other rice subpopulations to construct male and female parents. Despite the successful agronomic exploitation of heterosis in several crops, especially hybrid rice and hybrid maize, the molecular mechanisms underlying crop heterosis. Divergent selection and genetic introgression shape the.

The development of heterotic crops, especially those for hybrid rice and maize, is one of the most important applications of genetics in agriculture, and now over half of the rice and maize production worldwide is from hybrid. Heterosis has been widely applied in the breeding of agricultural crops, and its underlying mechanism has been studied for over 100 years darwin, 1876. In this study, heterosis in plant height was determined in two wheat hybrids, and it was found that the increased elongation. Hierarchical additive effects on heterosis in rice oryza sativa l.

Aug 29, 2006 in this study, we analyzed gene expression profiles of an elite rice hybrid and the parents at three stages of young panicle development, using a cdna microarray consisting of 9198 expressed sequence tags ests, with the objective to reveal patterns of gene expression that may be associated with heterosis in yield. Gibberellins and heterosis of plant height in wheat. Rice, superhybrid rice, heterosis, grain number, rnaseq background heterosis is a phenomenon in which hybrids exhibit superiority over their parental lines in economic traits, such as enhanced biomass production, development rate, stress tolerance and, most important, grain yield. Rice provides a good model crop for heterosis studies rice is the staple food crop currently feeding over half of the worlds population. D ominance and overdominance models have been proposed to explain single traitheterosis 32. The length of panicle, as a part of rice panicle architecture, contributes greatly to high yield. Heterosis for grain yield and its important components in. Hybrids are extensively used in agriculture to deliver an increase in yield, yet the molecular basis of heterosis is not well understood. Materials and methods this study was performed in the research farm of the university of agriculture peshawarpakistan, during the year 2011. In the present research, 12 lines were selected from 60 inbred rice bred by international rice research institute with extremelyhigh or low yielding records according to the previous three consecutive seasons of yield trial experiments, to construct a half diallel cross. Hybrid vigour, or heterosis, has been of tremendous importance in agriculture for the improvement of both crops and livestock.

Genomic landscapes of heterosis in hybrid rice population. Heterosis is a phenomenon in which hybrids exhibit superior performance relative to parental. Second, most 90% qtl contributing to heterosis appeared to be overdominant. Pdf combining ability and heterosis for agronomic and. Therefore, the present piece of research work reports. Consequently, systematic investigations of root heterosis, particularly in reproductivestage rice, are needed. Shull 1952 coined the term heterosis and defined it as. Heterosis studies for yield and its components in rice hybrids.

Neotetraploid rice, which is a new germplasm developed from autotetraploid rice, has a powerful biological and yield potential and could be used for commercial utilization. Notwithstanding large efforts to study the phenomenon of heterosis in the last decades, the identification of common molecular mechanisms underlying hybrid vigour remain rare. For commercial utilization of heterosis in rice, effective male sterility and fertility restoration systems are available and up to 45% natural outcrossing on male sterile. Consequently, systematic investigations of root heterosis. Heterosis or hybrid vigour in the first generation f 1 seeds, obtained by crossing genetically distant breeding lines, is well known in crop breeding shull, 1952. Heterosis evaluation of hybrids generated by crossing of autotetraploid with neotetraploid rice. The hybrid protein interactome contributes to rice. In this view, the superior performance of the hybrid is attributed to heterozygote combinations that compensate for deleterious mutations accumulating in each. Heterosis, heterobeltiosis and standard heterosis were studied in 14 crosses of rice oryza sativa l. More branches per panicle and more grains per branch.

Pdf heterosis for yield and yield components in rice. Edwards heterosis is the foundation of modern maize breeding programs. Carbohydrate metabolism and fertility related genes. The phenomenon that the heterozygous first filial f 1 generation often has better performance than its homozygous parents is known as heterosis or hybrid vigour1,2,3. This study was undertaken to assess the genetic variation and relationships among 40 autotetraploid rice genotypes and their counterpart diploid cultivars with 99 ssr markers screened from published. Genomic architecture of heterosis for yield traits in rice. Hybrid rice exploits the phenomenon of hetrosis which can increase the yield potential over hyvs. Transcriptome analysis of rice root heterosis by rnaseq. Heterosis breeding is the one of the strongest tool for breeder to complete targated demand of 2030 as rice is self pollinated species male sterility is essential for hybrid rice production. Analysis of the relationship between coefficients of. Analysis on genetic diversification and heterosis in. Ir36 and ir42 yield 45 tha in wet season trials and 78 tha in dry season trials. Plant breeders often cross different types of rice to produce hybrids with increased yields and other advantageous traits. A genomewide transcription analysis reveals a close.