Male Sterile Lines Research Articles

Interspecific hybridization with African marigold (Tagetes erecta) can improve flower-related performance in French marigold (T. patula)

The present research was intended for interspecific hybridization between two male sterile African marigold lines and six self-lines of French marigolds. The results show that as indicated by the full seed number per capitulum, the pollen amount of French marigold pollen influenced the authentic compatibilities reckoned for the 10 cross combinations configured to some amount. Based on the field performance of these interspecific hybrids, it is known that the parental French marigold’s single-petaled and silvery flower type may well be improved to a heavy-petaled type while the flower colour remains the same or changes to a lighter version with the same hue. Furthermore, the progeny of certain crossings exceeded the male parents in terms of growth, leaf, and flower-related features, particularly plant height, crown breadth, flower number per plant, and ligulate flower quantity. The most remarkable finding was that, compared to the parental French marigold, most of the hybrid combinations' progeny could blossom 0-11 days earlier. Finally, we identified two excellent hybrid combinations that may be used as a reference for future breeding and commercialization of new marigold varieties.

Species diversity of genus <em>Capsicum</em> using agromorphological descriptors and simple sequence repeat markers

Sustainability of crops in most demand depends upon their genetic diversity. Capsicum, commonly called chilli, is one such crop with its fruits extensively used as vegetable across the world. Knowledge on various traits is important for genetic improvement of such species. Here, we assessed the genetic diversity among 10 genotypes of six Capsicum species, namely Capsicum annuum, C. chinense, C. chacoense, C. frutescens, C. tovarii and C. galapagoense. C. annuum MS-12 is a genetic male sterile line. We used morphological descriptors and simple-sequence repeat (SSR) molecular markers for this study. Out of 60 SSR screened, 22 markers (36.66%) showed polymorphism. Alleles number per locus varied from 3 to 7. Average PIC value for 22 polymorphic markers was 0.69, and ranged from 0.54 for the primer Hpms 1-139 to 0.85 for the primer CAMS-072. Ten genotypes of Capsicum species were grouped into three major clusters such that genotypes in a single cluster had less dissimilarity matrix values among themselves than which belongs to other clusters. Range of fruit weight and pericarp thickness varied from 0.1 g (‘PAU-621’) to 2.3 g (‘MS-12’), and from 0.29 mm (‘PAU-621’) to1.09 mm (‘MS- 12’), respectively. These two genotypes can be used in hybridization or in recombinant breeding program for obtaining higher heterotic effects/ heterosis or for transgressive segregants in chilli pepper.

Targeted manipulation of grain shape genes effectively improves outcrossing rate and hybrid seed production in rice.

Stigma exsertion rate (SER) of the male sterile line is a key limiting factor for hybrid seed production in rice. Although a large number of quantitative trait loci associated with SER have been reported, few genes have been molecularly cloned and functionally characterized, severely hindering the genetic improvement of SER of the male sterile line and the breeding efficiency of hybrid rice. In this study, we identified three grain shape regulatory genes, GS3, GW8 and GS9, as potential candidate genes for targeted manipulation of grain shape and SER. We show that simultaneously knocking out these three genes could effectively increase SER by increasing the ratio of spikelet length/spikelet width and length of stigma and style, without negative impacts on other agronomic traits. Cellular examination and transcriptomic analyses revealed a role of these genes in coordinated regulation of transverse and longitudinal cell division in the pistils. Moreover, we demonstrate that targeted manipulation of these grain shape genes could significantly improve the outcrossing rate in both the ZH11 (a japonica variety) and Zhu6S (an indica male sterile line) backgrounds. Our results provide new insights into the mechanisms of rice SER regulation and develop an effective strategy to improve SER and out-crossing rate in rice, thus facilitating hybrid rice production.

The Use of the Polish Germplasm Collection of Nicotiana tabacum in Research and Tobacco Breeding for Disease Resistance

The Polish germplasm collection of Nicotiana tabacum was started in the 1920s. Up to now, more than eight hundred accessions originating from different regions of the world have been gathered in the collection. It includes valuable breeding lines and obsolete cultivars, among them cytoplasmic male-sterile lines. Numerous cultivars are rich sources of features desired in tobacco breeding. Therefore, the accessions are continually characterised in terms of their various features, one of the most important of which is disease resistance. Much research is being done to explain the nature of resistance and its genetic basis. Moreover, cultivars with good agronomic characteristics are used in wide hybridisation, being recipients of resistance genes from wild species or are genetically modified with transgenes conditioning resistance. The biological diversity of cultivars also allows a proper selection of plant material for pathogen studies, while the large number of the accessions facilitates research into the conditions for long seed storage. Numerous examples of the use of Polish tobacco germplasm in research and breeding, specifically in disease resistance, have been presented in this paper.

Comparative Transcriptome Analysis Reveals Key Insights into Fertility Conversion in the Thermo-Sensitive Cytoplasmic Male Sterile Wheat.

Thermo-sensitive cytoplasmic male sterility (TCMS) plays a crucial role in hybrid production and hybrid breeding; however, there are few studies on molecular mechanisms related to anther abortion in the wheat TCMS line. In this study, FA99, a new wheat thermo-sensitive cytoplasmic male sterility line, was investigated. Fertility conversion analysis showed that FA99 was mainly controlled by temperature, and the temperature-sensitive stage was pollen mother cell formation to a uninucleate stage. Further phenotypic identification and paraffin section showed that FA99 was characterized by indehiscent anthers and aborted pollen in a sterile environment and tapetum was degraded prematurely during the tetrad period, which was the critical abortion period of FA99. The contents of O2-, H2O2, MDA and POD were significantly changed in FA99 under a sterile environment by the determination of physiological indexes. Furthermore, through transcriptome analysis, 252 differentially expressed genes were identified, including 218 downregulated and 34 upregulated genes. Based on KOG function classification, GO enrichment and KEGG pathways analysis, it was evident that significant transcriptomic changes in FA99 under different fertility environments, and the major differences were "phenylalanine metabolism", "phenylpropanoid biosynthesis", "cutin, suberine and wax biosynthesis", "phenylalanine, tyrosine and tryptophan biosynthesis" and "citrate cycle (TCA cycle)". Finally, we proposed an intriguing transcriptome-mediated pollen abortion and male sterility network for FA99. These findings provided data on the molecular mechanism of fertility conversion in thermo-sensitive cytoplasmic male sterility wheat.

Evaluation of Advanced Mutant Restorer Lines for Enhancing Outcrossing Rate and Hybrid Seed Production of Diverse Rice Cytoplasmic Male Sterile Lines

Hybrid rice seed production predominantly relies on the pollen ability of restorer lines and the stigma properties of the cytoplasmic male sterile (CMS) lines. Improving the pollen ability and agronomic performance of restorer lines could be achieved using mutation to reinforce the outcrossing rate and seed set percentage of CMS lines. Two commercial restorer cultivars (Giza-178 and Giza-179) were treated with three different doses of gamma-ray; 200, 300, and 400 Gy. The derived mutant restorer lines were selfed and constantly evaluated with their corresponding parental cultivars until the M6 generation. Six promising mutant lines were chosen based on their performance to be evaluated with their parents for their pollen and agronomic characteristics. The novel-induced mutant restorer lines exhibited significant differences in all studied pollen and agronomic characteristics. The mutant restorer lines R4 and R7 exhibited superior desirable anther length (2.36 and 2.38 mm, in the same order), anther width (0.47 and 0.45 mm), pollen fertility (97.50 and 97.31%), basal pore length (218.8 and 299.5 mm), apical length (103.6 and 108.1), number of pollen grains per anther (1810 and 1832), plant height (121.8 and 115.9 cm), fertile tillers (23.50 and 18.89), number of spikelets per panicle (203.2 and 202.5), panicle length (25.34 and 24.26 cm), number of filled grains per panicle (195.5 and 191.8), seed set percentage (95.56 and 96.63%), and grain yield (11.01 and 11.36 t/ha). Based on the results of the first two seasons, the two novel promising restorers and their parental cultivars were crossed with four diverse CMS lines. The seed set percentage and hybrid seed production of the crossed CMS lines were evaluated for further two seasons. The results exposed that the combinations derived from restorer lines R4 and R7 with most of the evaluated CMS lines produced the uppermost seed set percentage outcrossing rate. Particularly in combination with CMS2, the restorer lines R4 and R7 displayed the highest seed set percentage (39.57 and 34.80%), number of tillers fertile per hill (25.31 and 23.32), seed yield (2.02 and 1.81 t/ha), and harvest index (23.88 and 22.66%). Conclusively, the derived gamma-ray-induced mutant restorer lines R4 and R7 could be exploited as a new source for ensuring desirable pollen and anther characteristics in order to improve the outcrossing rate of CMS lines and hybrid rice seed production.

Abnormal Programmed Cell Death of Tapetum Leads to the Pollen Abortion of Lycium barbarum Linnaeus

Programmed cell death (PCD) in tapetum provides nutrients for pollen development. Once this process becomes abnormal, the pollen will be aborted, and sterile lines will be formed. Lycium barbarum L. is a well-known medicinal and edible plant, and male sterile lines play an important role in the cultivation of its new varieties by utilizing hybrid vigor. However, the male sterility mechanism of L. barbarum is poorly understood. In this study, the main characteristic changes during the pollen development of L. barbarum sterile line (Ningqi No. 5) and fertile line (Ningqi No. 1) were compared through anatomical observation, physiological detection and gene expression analysis. Anatomical observation showed that compared with that of the fertile line, the tapetum of the sterile line persisted during pollen development, the organelle morphology and number of tapetal cells changed remarkably, and the PCD was remarkably delayed. Membranous peroxidation caused by reactive oxygen species (ROS) in the sterile line occurred from the late tetrad to the pollen grain stage, and that in Ningqi No. 1 transpired in the tetrad stage. This difference in the dynamic changes of ROS affected the redox balance of microspore development. qPCR detection of DYT1 and MS1 genes regulating tapetum development showed that compared with those in the fertile line, the expression levels of both genes in the sterile line changed significantly from pollen mother cell stage to pollen grain stage. This finding may be associated with the start-up delay of tapetal PCD. All these results suggested that abnormal tapetal PCD is an important mechanism leading to male sterility in L. barbarum.

A simple and efficient method for onion pollen preservation: Germination, dehydration, storage conditions, and seed production

The preservation of viable pollen is essential to overcome the problems related to the asynchronous flowering of the parental lines in onion hybrid breeding programs. The aim of this study was to establish a simple, inexpensive, and easily reproducible protocol for medium-term onion pollen storage. First, the conditions for assessing the in vitro pollen germination were optimized. The liquid medium favored the counting of germination of pollen grains in comparison to the solid medium. The addition of 75 mg/l Ca(NO3)2. 4H2O to the medium did not improve pollen germination, while that of 150 mg/l Ca(NO3)2. 4H2O inhibited pollen germination. The highest germination percentage was achieved by incubation at 30–35 °C in the dark. Second, fresh or dehydrated pollen (maintained in a desiccator with silica gel at 25 °C for 18 h) was stored at 4, –20, and –80 °C for two years to study pollen preservation. In addition, the viability and germination capacity of stored pollen were periodically evaluated at 0, 15 and 30 days; 2 and 6 months; and 1 and 2 years. Pollen viability was best retained at low relative humidity and temperatures below zero. Dehydration was essential for pollen preservation at –20 and –80 °C. The results showed that dehydrated pollen stored at –20 °C could be used, with guarantees, for pollination throughout the flowering season. However, the highest viability and in vitro germination percentages after two years of storage (29 and 32%, respectively) were achieved with dehydrated pollen stored at –80 °C. Finally, the capacity of stored pollen to produce seeds was confirmed in crosses with male sterile lines. In this way, dehydrated pollen stored at –80 °C for two years produced an average of 47.9 seeds/100 flowers, representing 43% of the seed in the control crosses. This is the first report in onion research of seed production after pollination with preserved pollen at –80 °C for two years.

Development of Two Novel Photoperiod and Thermo-Sensitive Genic Male Sterile Lines in Rice (Oryza sativa L.)

Development of Two Novel Photoperiod and Thermo-Sensitive Genic Male Sterile Lines in Rice (Oryza sativa L.)

Global transcriptome analysis reveals potential genes associated with genic male sterility of rapeseed (Brassica napus L.).

Rapeseed is the third leading source of edible oil in the world. Genic male sterility (GMS) lines provide crucial material for harnessing heterosis for rapeseed. GMS lines have been widely used successfully for rapeseed hybrid production. The physiological and molecular mechanism of pollen development in GMS lines of rapeseed (Brassica napus L.) need to be determined for the creation of hybrids and cultivation of new varieties. However, limited studies have focused on systematically mining genes that regulate the pollen development of GMS lines in B. napus. In the present study, to determine the stage at which pollen development begins to show abnormality in the GMS lines, we performed semi-thin section analysis of the anthers with five pollen development stages. The results indicated that the abnormal pollen development in DGMS lines might start at the meiotic stage, and abnormal pollen development in RGMS lines probably occurred before the tetrad stage. To investigate the critical genes and pathways involved in pollen development in GMS lines, we constructed and sequenced 24 transcriptome libraries for the flower buds from the fertile and sterile lines of two recessive GMS (RGMS) lines (6251AB and 6284AB) and two dominant GMS (DGMS) lines (4001AB and 4006AB). A total of 23,554 redundant DEGs with over two-fold change between sterile and fertile lines were obtained. A total of 346 DEGs were specifically related to DGMS, while 1,553 DEGs were specifically related to RGMS. A total of 1,545 DEGs were shared between DGMS and RGMS. And 253 transcription factors were found to be differentially expressed between the sterile and fertile lines of GMS. In addition, 6,099 DEGs possibly related to anther, pollen, and microspore development processes were identified. Many of these genes have been reported to be involved in anther and microspore developmental processes. Several DEGs were speculated to be key genes involved in the regulation of fertility. Three differentially expressed genes were randomly selected and their expression levels were verified by quantitative PCR (qRT-PCR). The results of qRT-PCR largely agreed with the transcriptome sequencing results. Our findings provide a global view of genes that are potentially involved in GMS occurrence. The expression profiles and function analysis of these DEGs were provided to expand our understanding of the complex molecular mechanism in pollen and sterility development in B. napus.

Determining Type of Sterility, Thresholds, Seeding Date and Rates of Arkansas Male Sterile Lines for Hybrid Seed Production

Two-line hybrid rice production requires environmental genetic male-sterile (EGMS) lines that become sterile in certain environmental conditions. In this study, we aimed to identify the genetic type(s), sterility thresholds, optimum planting date, and efficient seeding density of eight male-sterile lines, including four lines developed at the University of Arkansas, Rice Research and Extension Center (RREC) and four at the Dale Bumpers National Rice Research Center (DBNRRC) both located in Stuttgart, AR, USA. The lines were screened in growth chambers using different temperatures and day lengths to identify the type of EGMS line and sterility thresholds. A single location was used in testing the first year of the study and three locations used in the second year of the planting date study. All experiments were arranged in randomized blocks with three replications to identify the optimum planting date and seeding rate. Three planting dates were tested each year for the planting date experiment, and three seeding densities were used in the seed density study. The growth chamber study showed that all RREC lines were thermosensitive genic male-sterile lines, and the sterility threshold temperature for one of these lines was >32.2 °C while that of others was >29.4 °C. The type of sterility and threshold of DBNRRC lines were inconclusive due to their genetic heterogenicity and environmental response inconsistency. In Arkansas, April 25 was the optimum planting date for sterile conditions, and a 431 seed/m2 seeding rate was required to produce an adequate number of panicles for hybrid seed production while avoiding wasting expensive male-sterile seeds.

Gw2.1, a new allele of GW2, improves grain weight and grain yield in rice

Grain weight is an important characteristic of grain shape and a key contributing factor to the grain yield in rice. Here, we report that gw2.1, a new allele of the Grain Width and Weight 2 (GW2) gene, regulates grain size and grain weight. A single nucleotide substitution in the coding sequence (CDS) of gw2.1 resulted in the change of glutamate to lysine (E128K) in GW2.1 protein. Complementation tests and GW2 overexpression experiments demonstrated that the missense mutation in gw2.1 was responsible for the phenotype of enlarged grain size in the mutant line jf42. The large grain trait of the near-isogenic line NIL-gw2.1 was found to result from increased cell proliferation during flower development. Meanwhile, NIL-gw2.1 was shown to increase grain yield without compromising the grain quality. The GW2 protein was localized to the cell nucleus and membrane, and interacted with CHB705, a subunit of the chromatin remodeling complex. Finally, the F1 hybrids from crosses of NIL-gw2.1 with 7 cytoplasmic male-sterile lines exhibited large grains and desirable grain appearance. Thus, gw2.1 is a promising allele that could be applied to improve grain yield and grain appearance in rice. Availability of data and materialsThe datasets generated and/or analyzed in the study are available from the corresponding author on reasonable request.

Genome-Wide Identification and Expression Profiling Analysis of the Long-Chain Acyl-CoA Synthetases Reveal Their Potential Roles in Wheat Male Fertility.

Long-chain acyl-CoA synthetase (LACS), responsible for the conversion of free FAs into acyl-CoAs, is involved in multiple pathways of lipid metabolism. Although LACS genes in Arabidopsis have been well characterized, no detailed information concerning this family is available for wheat. In the present study, a systematic analysis was carried out for the wheat LACS family. As a result, 30 putative TaLACSs were identified. Expression analysis revealed that 22 Takacs were expressed in wheat anthers. Two orthologs of AtLACS1, TaLACS2 and TaLACS3, were repressed at the vacuolated stage in the cold-treated BS366 (a temperature-sensitive genic male-sterile line). Thus, TaLACS2 and TaLACS3 may function like AtLACS1 in wax biosynthesis in anthers, and the repression of both genes may be correlated with the male sterility of BS366. TaLACS5 is an ortholog of AtLACS5, which was expressed exclusively in anthers. TaLACS5 was repressed in the cold-treated BS366 at the tetrad, uninucleate, and vacuolated stages. The negative correlation between TaLACS5 and TaGAMYB-B, and the MYB domain found in the promoter sequence suggested that TaLACS5 may be negatively regulated by TaGAMYB-B to participate in wheat fertility. These findings will provide a valuable foundation for the understanding of the wheat LACS gene family in male fertility.

In vivo maternal haploid induction based on genome editing of DMP in Brassica oleracea.

In vivo maternal haploid induction based on genome editing of DMP in Brassica oleracea.

Characterization, inheritance of male sterility and development of male sterile and maintainer lines in ridge gourd (Luffa acutangula (Roxb.) L.)

Two male sterile mutants IIHRRG-12MS (long fruited) and IIHRRG-28MS (medium long fruited) were identified from the ridge gourd germplasm IIHR-12 and IIHR-28 respectively at ICAR-IIHR, Bengaluru. These two male-sterile (ms) sources were characterized by the production of rudimentary male flowers in the racemes in contrast to the bright yellow flowers with fertile pollen and healthy anthers in male fertile, monoecious plants. Using these ms lines the inheritance of male sterility was worked out, which is cytoplasmic genic male sterility (CGMS) type, with single dominant gene either in homozygous or heterozygous condition restoring male fertility in the presence of sterile cytoplasm. In order to develop F1 hybrids using male sterility, several male sterile and maintainer lines were developed in different genetic back grounds such as green/dark green fruit colour and short/medium long/long fruit length.

Cytochrome P450 mono-oxygenase CYP703A2 plays a central role in sporopollenin formation and ms5ms6 fertility in cotton.

The double-recessive genic male-sterile (ms) line ms5 ms6 has been used to develop cotton (Gossypium hirsutum) hybrids for many years, but its molecular-genetic basis has remained unclear. Here, we identified the Ms5 and Ms6 loci through map-based cloning and confirmed their function in male sterility through CRISPR/Cas9 gene editing. Ms5 and Ms6 are highly expressed in stages 7-9 anthers and encode the cytochrome P450 mono-oxygenases CYP703A2-A and CYP703A2-D. The ms5 mutant carries a single-nucleotide C-to-T nonsense mutation leading to premature chain termination at amino acid 312 (GhCYP703A2-A312aa ), and ms6 carries three nonsynonymous substitutions (D98E, E168K, and G198R) and a synonymous mutation (L11L). Enzyme assays showed that GhCYP703A2 proteins hydroxylate fatty acids, and the ms5 (GhCYP703A2-A312aa ) and ms6 (GhCYP703A2-DD98E,E168K,G198R ) mutant proteins have decreased enzyme activities. Biochemical and lipidomic analyses showed that in ms5 ms6 plants, C12-C18 free fatty acid and phospholipid levels are significantly elevated in stages 7-9 anthers, while stages 8-10 anthers lack sporopollenin fluorescence around the pollen, causing microspore degradation and male sterility. Overall, our characterization uncovered functions of GhCYP703A2 in sporopollenin formation and fertility, providing guidance for creating male-sterile lines to facilitate hybrid cotton production and therefore exploit heterosis for improvement of cotton.

QTL Analysis and Heterosis Loci of Effective Tiller Using Three Genetic Populations Derived from Indica-Japonica Crosses in Rice

Effective panicle numbers (PNs) and Tiller numbers (TNs) are important traits affecting rice (Oryza sativa L.) architecture and grain yield. However, the molecular mechanisms underlying PN and TN heterosis remain unknown in rice. In addition, new PN- or TN-related genes need to be detected and discovered. In this study, in order to detect rice quantitative trait loci (QTLs) and the heterosis-related loci of PN or TN in rice, we developed a high generation recombinant inbred line (RIL) population from a cross of two elite cultivars, Luohui9 (Xian/Indica) and RPY geng (Geng/Japonica), and two testcross hybrid populations derived from the crosses of RILs and two cytoplasmic male sterile lines, YTA (Xian/Indica) and Z7A (Geng/Japonica). Finally, nine QTLs of PN across four seasons were identified, and two QTLs of TN in 191HB were mapped. Besides this, six heterosis-related QTLs of PN and five heterosis-related QTLs of TN were located. We found that heterosis-related QTLs of PN or TN covered multiple known genes, such as MOC1, TAC1 and OsETR2. Furthermore, homologous gene analysis identified one candidate gene of PN (LOC_10g25720). Together, these findings uncover multiple heterosis-related loci, and provide a new insight into the heterosis mechanism of PN and TN in rice.

Epigenetic Dynamics and Regulation of Plant Male Reproduction.

Flowering plant male germlines develop within anthers and undergo epigenetic reprogramming with dynamic changes in DNA methylation, chromatin modifications, and small RNAs. Profiling the epigenetic status using different technologies has substantially accumulated information on specific types of cells at different stages of male reproduction. Many epigenetically related genes involved in plant gametophyte development have been identified, and the mutation of these genes often leads to male sterility. Here, we review the recent progress on dynamic epigenetic changes during pollen mother cell differentiation, microsporogenesis, microgametogenesis, and tapetal cell development. The reported epigenetic variations between male fertile and sterile lines are summarized. We also summarize the epigenetic regulation-associated male sterility genes and discuss how epigenetic mechanisms in plant male reproduction can be further revealed.

Increasing seed set and pollen proofing in Brassica juncea and Brassica napus through novel non-woven synthetic pollination control bags

ABSTRACT Brassica juncea and B. napus species are predominantly self-pollinated. Parchment paper or muslin cloth bags are used for controlled selfed or cross-seed production. We evaluated three non-woven synthetic pollination control bags (PCBs) for two years as replacement for the commonly used PCBs. The new synthetic PCBs were fully pollen proof since the molecular marker analysis of the random seeds set on two cytoplasmic male sterile (CMS) lines isolated with PCBs were all maternally originated. DWB03 bags returned 47% significantly more seeds per bud than the parchment paper bags. Larger DWB03 bags showed 38% higher mean seed yield (g/plant) than the muslin cloth bags. Re-used DWB03 bags were statistically on par with new bags for the seed yield per plant. On average, DWB03 bags produced 57% more hybrid seed set on CMS lines than the muslin cloth bags. The micro-climate in DWB03 bags appeared to be more conducive for good seed set as compared to the outside and muslin cloth bags. Non-woven PCBs offer better options for replacing paper or muslin cloth bags in the breeding of Brassicas.

Current Scenario of Crop Improvement of Finger Millet [Eleusine coracana (L.)] in India: A Review

Finger millet [Eleusine coracana (L.) Gaertn.] is an ancient and important millet crop of India. The crop is predominantly grown as rainfed crop in the peninsular Indian states. The crop has shown numerous advantages over major cereals in terms of stress adaptation, nutritional quality and health benefits. Finger millet is highly self pollinated crop. Hybridization in finger millet is difficult due to small cleistogamous florets. Presently hot-water treatment followed by contact method of crossing is widely used across institutes for generating breeding populations. The availability of versatile male sterile systems could enhance hybridization in the crop. A novel male sterile line PS1, developed and maintained just by growing in isolation and thus improving its accessibility for hybridization. The varieties in finger millet released over a period of time were by adapting hybridization followed by selection. Till now, a total of 141 varieties of finger millet have been developed and released in the country. Finger millet occupies a prime position among millets. Realizing the nutritional importance, it is now in high demand. Knowledge on the improved production strategies right from selection of high yielding varieties to market led extension and extensive usage at national and global level has a vital role. The review, therefore, provided detailed information on hybridization methods, crop improvement and details of recently released varieties and their adaptation in finger millet.