Conventional Breeding Research Articles

Haplotype breeding: fast-track the crop improvements.

Haplotype-based breeding unleashed the genetic variations of unexplored germplasms and integration with recent genomics tools accelerated the genetic gain and address the present challenges of food security by climate change. Climate change is linked to unforeseenabiotic stressesand changes in the patterns of pests and diseases. Hence, it is necessary to use novel methods to detect genetic variations to mitigate the adverse effects on crops by climate change. Genomic-assisted breeding methods are strategies that improve the efficiency of breeding cereal crops in a dynamic environment. These methods detect differences in the structure of single nucleotide polymorphisms (SNPs) throughout the population. The decrease in sequencing costs has enabled the thorough sequencing of crop genomes, resulting in the discovery of millions of SNPs. By using statistical tests, it is possible to integrate these SNPsinto a limited number of haplotype blocks. This allows for a more comprehensive analysis of how variation is distributed and segregated within a population. Therefore, the use of haplotype-based breeding shows great potential as a tool for creating tailored crop varieties. The process entails the identification of superior haplotypes and their use in breeding operations. The haplotype-based breeding (HBB) technique utilizes genome sequence data to identify specific allelic variations that accelerate the breeding cycle and overcome linkage drag difficulties. This study aims to present the idea of HBB, examine the connection between haplotype breeding and conventional breeding, and analyze the benefits and current advancements of HBB, with a specific focus on cereal crops.

In vitro Anther culture and Production of Haploids in Cannabis sativa

Cannabis sativa has been used for thousands of years for recreational, medicinal, or religious purposes. Another culture technique is the most viable and efficient method of producing homozygous doubled haploid plants within a short period. The most widely extended approaches to obtain doubled haploids (DHs) have traditionally been based on the use of haploid cells of male or female origin to induce their development as haploid embryos by the application of different stresses under in vitro conditions. They are the so-called in vitro approaches. Thus, the long process of conventional breeding methods can be reduced by homozygosity in early generations. The recessive alleles could be obtained and selected earlier due to the homozygosity of doubled haploids (DHs) lines. Double haploid technology (DH) is an essential tool in plant breeding, enabling the rapid production of homozygous lines. However, doubled haploids (DH) were not highly relevant in plant breeding until researchers at the Department of Botany in the University of Delhi, India, reported a major breakthrough in the production of haploids from anther culture in Datura innoxia (Guha and Maheshwari, 1964, 1966). Their research revolutionized the use of doubled haploid (DH) technology in plant breeding worldwide. However, the practical application of this technology in Cannabis sativa improvement is still limited by various factors that influence culture efficiency. Cannabis sativa L. has been categorized as recalcitrant to doubled haploid (DH) induction and androgenesis induction, although very few embryos can be developed. However, the potential of in vitro anther culture in Cannabis sativa is yet to be completely exploited mainly due to the recalcitrant genetic backgrounds in Cannabis sativa.

Blood biochemistry changes in a minipig infarction model

IntroductionThe present study aimed to assess changes in biochemical parameters during the adaptation of the myocardial infarction model to a conventional Hungarian minipig breed. According to our hypothesis, changes in the blood level of the necroenzymes are not only related to the interventional procedure but are also influenced by peri-procedural animal keeping and treatment conditions.MethodsClosed chest acute myocardial infarction (AMI) was induced by balloon occlusion for 90 min in the left anterior descendent coronary artery (LAD) in 24 adult, female Pannon minipigs followed by reperfusion. Blood samples were taken before AMI, and immediately after the reperfusion, during the cardiac magnetic resonance imaging (cMRI) on days 3 and 30. Aspartate transaminase (AST), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LDH), and high-sensitivity troponin I were determined.ResultsWhile the parameters measured at baseline remained within physiological ranges, a notable elevation was seen in comparison with the results observed on day 30. This phenomenon was evident in all the laboratory parameters tested, except hs-troponin. The results for AST, ALT, LDH, and CK were statistically significant (p = 0.011, p = 0.001, p = 0.013, and p = 0.001, respectively). A statistically significant difference was observed between the baseline and 30-day AST/ALT ratio (p = 0.00514).DiscussionThe elevated levels of necroenzymes observed at baseline are likely to be a consequence of the physical and social stress imposed by the study design on the minipigs during the 72-h period prior to intervention. It is essential to define the optimal timing of baseline blood tests to ensure the reliability of the biochemical profile in a large animal infarction model.

Isolation and characterization of haploid heterothallic beer yeasts

Improving ale or lager yeasts by conventional breeding is a non-trivial task. Domestication of lager yeasts, which are hybrids between Saccharomyces cerevisiae and Saccharomyces eubayanus, has led to evolved strains with severely reduced or abolished sexual reproduction capabilities, due to, e.g. postzygotic barriers. On the other hand, S. cerevisiae ale yeasts, particularly Kveik ale yeast strains, were shown to produce abundant viable spores (~ 60%; Dippel et al. Microorganisms 10(10):1922, 2022). This led us to investigate the usefulness of Kveik yeasts for conventional yeast breeding. Surprisingly, we could isolate heterothallic colonies from germinated spores of different Kveik strains. These strains presented stable mating types in confrontation assays with pheromone-sensitive tester strains. Heterothallism was due to inactivating mutations in their HO genes. These led to amino acid exchanges in the Ho protein, revealing a known G223D mutation and also a novel G217R mutation, both of which abolished mating type switching. We generated stable MATa or MATα lines of four different Kveik yeasts, named Odin, Thor, Freya and Vör. Analyses of bud scar positions in these strains revealed both axial and bipolar budding patterns. However, the ability of Freya and Vör to form viable meiotic offspring with haploid tester strains demonstrated that these strains are haploid. Fermentation analyses indicated that all four yeast strains were able to ferment maltose and maltotriose. Odin was found to share not only mutations in the HO gene, but also inactivating mutations in the PAD1 and FDC1 genes with lager yeasts, which makes this strain POF-, i.e. not able to generate phenolic off-flavours, a key feature of lager yeasts. These haploid ale yeast-derived strains may open novel avenues also for generating novel lager yeast strains by breeding or mutation and selection utilizing the power of yeast genetics, thus lifting a block that domestication of lager yeasts has brought about.Key points• Haploid Kveik ale yeasts with stable MATa and MATα mating types were isolated.• Heterothallic strains bear mutant HO alleles leading to a novel inactivating G217R amino acid change.• One strain was found to be POF- due to inactivating mutations in the PAD1 and FDC1 gene rendering it negative for phenolic off-flavor production.• These strains are highly accessible for beer yeast improvements by conventional breeding, employing yeast genetics and mutation and selection regimes.

Generation and propagation of high fecundity gene edited fine wool sheep by CRISPR/Cas9

CRISPR/Cas9 technology has been widely utilized to enhance productive performance, increase disease resistance and generate medical models in livestock. The FecB allele in sheep is a mutation in the BMPRIB gene, recognized as the first major gene responsible for the high fecundity trait in sheep, leading to an increased ovulation rate in ewe. In this study, we employed CRISPR/Cas9-mediated homologous-directed repair (HDR) to introduce a defined point mutation (c.746 A > G) using single-stranded oligonucleotides (ssODN) and the ligase IV inhibitor (SCR7) into the BMPRIB gene of fine wool sheep. A total of nine gene-edited sheep were produced, six of which carried the targeted point mutation, with a precise base substitution efficiency (A > G) of 31.6%. Based on the six targeted founders (F0), we expanded the BMPRIB-targeted population, which included F1 heterozygous (B+) and F2 homozygous(BB) or heterozygous offspring. The average litter size of F1 ewes carrying the B + allele reached 170%, comparable to that of heterozygous native Australian Booroola sheep. Gene-edited ewes with B + and BB genotype produced 0.62 and 0.42 more lambs, respectively, compared to wide-type ewes (p < 0.01). Our results also indicated that the parity signification, our data demonstrate that highly efficient introduction of the intended base mutation into the sheep genome can be achieved by combining the CRISPR/Cas9 system with ssODN and SCR7. The offspring of BMPR/B edited sheep with the defined mutation exhibited high fecundity performance. Compared to conventional sheep breeding strategies, genetic improvement through gene editing offered significant advantages without compromising the fine wool traits of Merino sheep, which are often affected by routine cross-breeding methods.

Carotenoids in Potato Tubers: A Bright Yellow Future Ahead.

Carotenoids, the bright yellow, orange, and red pigments of many fruits and vegetables, are essential components of the human diet as bioactive compounds not synthesized in animals. As a staple crop potato has the potential to deliver substantial amounts of these nutraceuticals despite their lower concentration in tubers compared to edible organs of other plant species. Even small gains in tuber carotenoid levels could have a significant impact on the nutritional value of potatoes. This review will focus on the current status and future perspectives of carotenoid biofortification in potato with conventional breeding and biotechnological approaches. The high biodiversity of tuber carotenoid levels and composition is presented, with an emphasis on the under-exploited native germplasm that represents a wide reservoir of useful genetic variants to breed carotenoid-rich varieties. The following section describes the structural genes involved in carotenoid metabolism and storage known to have a major impact on carotenoid accumulation in potato, together with the strategies that harnessed their expression changes to increase tuber carotenoid content. Finally, the little information available on the regulation of carotenoid metabolism and the desirable future advances in potato carotenoid biofortification are discussed.

Integrative approaches for mustard improvement: Bridging conventional breeding, genetics and biotechnological advances

Mustard is globally an oilseed crop that provides essential edible oil and industrial raw materials, particularly in regions like South Asia, Europe, and Canada, where it plays a critical role in agricultural economies and food industries. However, worldwide biotic and abiotic stresses pose major challenges to mustard production. Advances in conventional breeding techniques, genetics, and biotechnological tools hold immense potential for developing improved mustard varieties. This review elucidates the evolution of mustard breeding, moving from conventional approaches to advanced molecular tools that allow for precise genetic modifications, enhancing mustard resilience and yield. It highlights the roles of phenotypic and genotypic selection, molecular markers, transgenics, and genomicsassisted breeding in augmenting mustard improvement endeavours. The promise of emerging technologies like genome editing and systems biology is discussed for mustard genetic enhancement and climate-resilient varietal development. The review emphasizes the need of collaboration among research institutions, public-private partnerships, and international networks to accelerate, sustainable mustard improvement efforts.

Climate-resilient crops: Integration of molecular tools into conventional breeding

Climate-resilient crops: Integration of molecular tools into conventional breeding

In vitro mutation induction of raspberry species (Rubus) using gamma ray irradiation

AbstractRaspberry species produce highly nutritious fruits that are used for fresh consumption and frozen and processed products, such as jellies, juices, jams, and desserts. Efforts have been made to improve raspberry yield and fruit quality using conventional breeding. However, the narrow genetic diversity in raspberry species limits the progress of raspberry breeding. In this study, in vitro leaf and petiole tissues of three raspberry cultivars, ‘Amethyst,’ ‘Joan J,’ and ‘Polana,’ were irradiated with gamma rays at 0, 25, 50, or 100 Gy for mutation induction. In vitro shoots were then regenerated from the gamma ray–irradiated tissues in woody plant medium (WPM) supplemented with 20.0 g·L−1 sucrose, 6.5 g·L−1 agar, 200.0 mg·L−1 polyvinylpyrrolidone (PVP), and 1.0 µM thidiazuron (TDZ). Regenerated shoots were rooted in one-half MS medium containing 0.5 µM naphthaleneacetic acid (NAA). Rooted plants were first grown in the greenhouse and the survived raspberry plants were planted in the field. Results showed that gamma ray irradiation significantly decreased the shoot regeneration of the three raspberry cultivars; however, three raspberry cultivars responded differently to gamma ray irradiation in shoot regeneration. Of which ‘Joan J’ and ‘Amethyst’ were more tolerant to gamma ray irradiation than ‘Polana.’ More shoots were regenerated from leaf tissues than from petiole tissues. Morphological variations in leaf, cane, plant structure, and fruit were observed in the field. This research demonstrates that in vitro mutation induction using gamma ray irradiation could be a useful tool to develop genetic materials that have potential for breeding and germplasm improvement of raspberry and other Rubus species.

Genetic Improvement of Banana for Resistance to Xanthomonas Wilt in East Africa

ABSTRACTBanana (Musa spp.) is a staple food and income generation crop, feeding millions worldwide. However, the cultivation of bananas is challenging due to biotic and abiotic production constraints. Among these factors are pests and diseases, especially banana bacterial disease. Banana Xanthomonas wilt (BXW), caused by Xanthomonas campestris pathovar musacearum (Xcm), has the most significant detrimental economic effect on East African banana production. The infection of BXW is rapid and severe; its impact increases over time and causes huge banana yield losses. The Xcm infects and causes disease in all types of bananas except the wild diploid type Musa balbisiana, which is resistant boosting plant immunity for controlling Xcm and other diseases in bananas. Resistant cultivars are the best promising management option for controlling Xcm and other diseases in bananas. All the cultivated bananas are sterile, and have a long generation cycle, which complicates their improvement through conventional breeding. Biotechnological approaches to banana improvement can complement conventional breeding by overcoming some of its challenges. Additionally, genetic engineering could speed up the process of crop improvement, especially for sterile seedless crops like bananas. It is also specific to the target gene and precise modification that avoids unwanted genes in the normal breeding process. Recent developments using genetic engineering and genome editing on bananas have been initiated to tackle these issues. This review article focuses on the challenges of traditional breeding and the progress of genetic engineering and genome editing approaches, aiming to enhance understanding of achieving an essential genetic gain of bananas against the BXW. This understanding is crucial for enhancing food security in East Africa and globally.

Evaluating genomic selection and speed breeding for Fusarium head blight resistance in wheat using stochastic simulations

Genomic selection-based breeding programs offer significant advantages over conventional phenotypic selection, particularly in accelerating genetic gains in plant breeding, as demonstrated by simulations focused on combating Fusarium head blight (FHB) in wheat. FHB resistance, a crucial trait, is challenging to breed for due to its quantitative inheritance and environmental influence, leading to slow progress using conventional breeding methods. Stochastic simulations in our study compared various breeding schemes, incorporating genomic selection (GS) and combining it with speed breeding, against conventional phenotypic selection. Two datasets were simulated, reflecting real-life genotypic data (MASBASIS) and a simulated wheat breeding program (EXAMPLE). Initially a 20-year burn-in phase using a conventional phenotypic selection method followed by a 20-year advancement phase with three GS-based breeding programs (GSF2F8, GSF8, and SpeedBreeding + GS) were evaluated alongside over a conventional phenotypic selection method. Results consistently showed significant increases in genetic gain with GS-based programs compared to phenotypic selection, irrespective of the selection strategies employed. Among the GS schemes, SpeedBreeding + GS consistently outperformed others, generating the highest genetic gains. This combination effectively minimized generation intervals within the breeding cycle, enhancing efficiency. This study underscores the advantages of genomic selection in accelerating breeding gains for wheat, particularly in combating FHB. By leveraging genomic information and innovative techniques like speed breeding, breeders can efficiently select for desired traits, significantly reducing testing time and costs associated with conventional phenotypic methods.

Integration of multi‐omics approaches reveals candidate genes for drought stress in St. Augustinegrass (Stenotaphrum secundatum)

AbstractThere is growing demand across the turfgrass industry for turfgrasses that require minimal watering. St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze], a warm‐season turfgrass favored in the southeastern United States for its shade tolerance and vigorous stoloniferous growth, falls short in drought resistance. Integrating genomic and conventional breeding methodologies could accelerate the introduction of cultivars that thrive with less water. In this study, a population derived from the cross of breeding lines XSA10098 and XSA10127 was evaluated for drought resistance in field trials, where percent green cover and normalized difference vegetation index were collected by unmanned aerial vehicle‐based phenotyping. A multiple quantitative trait loci (QTL) mapping approach identified 22 QTL, with overlapping regions on linkage groups 1, 2, 4, and 9 between this and previous studies. In addition, a detailed transcriptomic analysis on the roots of two St. Augustinegrass genotypes with contrasting drought responses revealed 1642 and 2669 differentially expressed genes (DEGs) in the drought‐tolerant and drought‐sensitive genotypes, respectively. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes classification showed different pathways adopted by the two genotypes in response to drought stress. Moreover, integration of QTL mapping and transcriptomic analyses identified five DEGs co‐localized in overlapping QTL regions, which exhibit great value to potentially serve as targets to facilitate marker‐assisted selection. The findings in this study contribute to a deeper understanding of the genetic basis of drought tolerance in St. Augustinegrass, facilitating the development of more robust breeding strategies for enhancing drought resilience in this important turfgrass species.

Effects of Climatic Conditions and Agronomic Practices on Health, Tuber Yield, and Mineral Composition of Two Contrasting Potato Varieties Developed for High and Low Input Production Systems

Modern potato varieties from high-input, conventional farming-focused breeding programs produce substantially (up to 45%) lower yields when grown in organic production systems, and this was shown to be primarily due to less efficient fertilization and late blight (Phytophthora infestans) control methods being used in organic farming. It has been hypothesized that the breeding of potato varieties suitable for the organic/low-input sector should (i) focus on increasing nutrient (especially N) use efficiency, (ii) introduce durable late blight resistance, and (iii) be based on selection under low-input conditions. To test this hypothesis, we used an existing long-term factorial field experiment (the NEFG trials) to assess the effect of crop management practices (rotation design, fertilization regime, and crop protection methods) used in conventional and organic farming systems on crop health, tuber yield, and mineral composition parameters in two potato varieties, Santé and Sarpo mira, that were developed in breeding programs for high and low-input farming systems, respectively. Results showed that, compared to Santé, the variety Sarpo mira was more resistant to foliar and tuber blight but more susceptible to potato scab (Streptomyces scabies) and produced higher yields and tubers with higher concentrations of nutritionally desirable mineral nutrients but lower concentrations of Cd. The study also found that, compared to the Cu-fungicides permitted for late blight control in organic production, application of synthetic chemical fungicides permitted and widely used in conventional production resulted in significantly lower late blight severity in Sante but not in Sarpo mira. Results from both ANOVA and redundancy analysis (RDA) indicate that the effects of climatic (precipitation, radiation, and temperature) and agronomic (fertilization and crop protection) explanatory variables on crop health and yield differed considerably between the two varieties. Specifically, the RDA identified crop protection as a significant driver for Santé but not Sarpo mira, while precipitation was the strongest driver for crop health and yield for Sarpo mira but not Santé. In contrast, the effect of climatic and agronomic drivers on tuber mineral and toxic metal concentrations in the two varieties was found to be similar. Our results support the hypothesis that selection of potato varieties under low agrochemical input conditions can deliver varieties that combine (i) late blight resistance/tolerance, (ii) nutrient use efficiency, and (iii) yield potential in organic farming systems.

Adaptation des cultures au changement climatique : apport possible de l'édition génomique

Climate change means warmer conditions, with more frequent risks of drought, but also a wide variation in conditions, with extreme events, from one year to the next. To adapt crops to this change, we need varieties that combine several types of tolerance, particularly to high temperatures and water stress at different stages of the plant life, as well as resistance to different types of bio-aggressors associated to this change. Using various examples, we show that genome-editing techniques can be a tool to assist conventional plant breeding in obtaining such varieties more quickly. In the discussion, we compare the selection of varieties adapted to different conditions (called multi-adapted varieties), thanks to genome editing, with the mixture of varieties with adaptations to different climatic conditions, and we conclude that the two approaches can be complementary.

Assessment of the usability of four molecular markers to ıdentify potato genotypes suitable for processing

The development of processing potato cultivars through a conventional breeding program requires a detailed analysis of post-harvest traits, which is a process that demands high labor and is often time-consuming. Visual selection by breeders is biased and difficult in the field, particularly for quality traits, which shows the importance of marker-assisted selection over conventional techniques. In this study, four allele-specific markers, AGPsS-9a, Stp23-8b, StpL-3e, and Pain1-8c, developed from tuber quality-related genes, were used to screen a breeding population of the NOHU for processing traits to check the efficiency of these markers in processing trait selection. Marker association with tuber quality trait results showed that AGPsS-9a (0, absent) and StpL-3e (0) individually were associated with increased chips quality, yet their individual presence improved the reducing sugar content. Further, Pain1-8c presence was associated with high levels of reducing sugar accumulation and lower dry matter content, specific gravity, and starch content. The marker combination Stp23-8b (0) and StpL-3e (0) reached statistical significance (P≤0.05) for better chips quality in the NOHU population. However, the markers (individual and combination) showed poor selection efficiency as a diagnostic marker, possibly reasoning from the multigenic inheritance of tuber quality traits, population structure, and environment.

Genetic analysis for forage yield and quality characters in cowpea (Vigna unguiculata L. Walp)

This study was carried out to determine the combining ability of forage yield, its components and quality traits among crosses derived from nine selected cowpea parents. About 36 crosses were generated from diallel crosses, excluding reciprocals. These crosses and nine parents were evaluated for combining ability for forage yield, its components and quality traits. The results indicated that parent 85-5E was the best combiner for green fodder yield, dry matter yield, leaf length, leaf breadth, number of leaves per plant, number of branches per plant, crude protein content and in-vitro dry matter digestibility. Similarly, parent FOS 1 proved to be the best combiner for vine length, number of leaves per plant, number of branches per plant, crude protein content and in-vitro dry matter digestibility. The crosses involving FOS 1 x CL 398, CL 391 x C 88, FOS 1 x C 74, CL 396 x CL 391 and FOS 1 x C 88 were the best specific combiner for green fodder yield and most of its components traits. The ratio of gca/sca values was greater than unity for most of the forage and quality traits, inferring that additive gene action played an important role in their inheritance. In contrast, for traits like vine length, dry matter yield, crude protein content, and in-vitro dry matter digestibility, the above-said ratio was less than unity, indicating non-additive gene action played an important role. So, to utilize both additive and non-additive gene effects, modification of conventional breeding methods such as bi-parental breeding or reciprocal recurrent selection will be the better choice for initiating any cowpea breeding program.

SgR1, Encoding a Leucine-Rich Repeat Containing Receptor-like Protein, Is a Major Aphid (Schizaphis graminum) Resistance Gene in Sorghum.

Greenbug, Schizaphis graminum, is one of the important cereal aphid pests of sorghum in the United States and other parts of the world. Sorghum bicolor variety PI 607900 carries the Schizaphis graminum resistance (SgR1) gene that underlies plant resistance to greenbug biotype I (GBI). Now, the SgR1 has been determined as the major gene conferring greenbug resistance based on the strong association of its presence with the resistance phenotype in sorghum. In this study, we have successfully isolated the SgR1 gene using a map-based cloning approach, and subsequent molecular characterization revealed it encodes a leucine-rich repeat containing receptor-like protein (LRR-RLP). According to DNA sequence analysis, the SgR1 gene are conserved among GBI-resistance sorghum accessions but are variable within susceptible lines. Furthermore, an InDel (-965 nt) at its promoter region and a single-nucleotide polymorphism (SNP, 592 nt) in the CDS of the SgR1 were detected and they are well conserved within resistant genotypes. When the SgR1 gene was cloned and transferred into Arabidopsis plants, the SgR1 was activated in the transgenic Arabidopsis plants in response to attack by green peach aphids according to the results of the histochemical assay, and GUS activity was detected in situ in spots around the vasculature of the leaf where the phloem is located, suggesting its biological function in those transgenic Arabidopsis plants. Overall, this study confirms that the SgR1 gene coding for an LRR-RLP is the major resistance gene to greenbug, a destructive pest in sorghum and wheat. This represents the first greenbug resistance gene cloned so far and indicates that the simple-inherited GBI resistance gene can be used for sorghum improvement with genetic resistance to GBI via molecular breeding or cross-based conventional breeding technologies.

The complexity of kodo millet: genomic analysis and implications in crop improvement.

This article explores possible future initiatives, such as the development of targeted breeding and integrated omics approach to boost kodo millet production, nutritional value, and environmental adaptation. Kodo millet is grouped under the genus Paspalum and family Gramineae. It is a tropical African crop that was initially domesticated in India approximately 3000years ago. It is predominantly cultivated in India as well as in various south-east Asian countries. Recent years have witnessed a resurgence of interest in kodo millet breeding, particularly owing to its outstanding nutritional profile. Kodo millet's ability to adapt to different marginal environments makes it promising to be grown as a part of sustainable agriculture. Availability of a plethora of diverse genetic resources in kodo millet has been instrumental in development of various improved cultivars through conventional breeding. Additionally, functional genomics has been instrumental in decoding the complex genetic architecture of kodo millet, thus enabling identification of key genes associated with drought tolerance, disease resistance, and improved nutritional profiling. Additionally, transcriptomics has deepened the insights into gene expression pattern in response to various stresses, offering valuable information for developing resistant genotypes. The expressed sequence tags (ESTs) available will surely benefit the scientists working on molecular breeding of millets through development and use of SSRs and SNPs markers under the marker assisted selection (MAS) scheme. This article examines potential directions for future research, including the advancement of genomics and targeted breeding approaches for holistic development of the kodo millet.

Insight into Rice Resistance to the Brown Planthopper: Gene Cloning, Functional Analysis, and Breeding Applications.

This review provides a comprehensive overview of the current understanding of rice resistance to the brown planthopper (BPH), a major pest that poses significant threats to rice production through direct feeding damage and by transmitting viruses such as Rice grassy stunt virus (RGSV) and Rice ragged stunt virus (RRSV). We highlight the emergence of various BPH biotypes that have overcome specific resistance genes in rice. Advances in genetic mapping and cloning have identified 17 BPH resistance genes, classified into typical R genes encoding nucleotide-binding leucine-rich repeat (NLR) proteins and atypical R genes such as lectin receptor kinases and proteins affecting cell wall composition. The molecular mechanisms of these genes involve the activation of plant defense pathways mediated by phytohormones like jasmonic acid (JA), salicylic acid (SA), and ethylene, as well as the production of defensive metabolites. We also examine the complex interactions between BPH salivary proteins and rice defense responses, noting how salivary effectors can both suppress and trigger plant immunity. The development and improvement of BPH-resistant rice varieties through conventional breeding and molecular marker-assisted selection are discussed, including strategies like gene pyramiding to enhance resistance durability. Finally, we outline the challenges and future directions in breeding for durable BPH resistance, emphasizing the need for continued research on resistance mechanisms and the development of rice varieties with broad-spectrum and long-lasting resistance.

Micropropagation of coconut (Cocos nucifera Linn var. pandan) through somatic embryogenesis technique

Coconut, also known as Cocos nucifera, is one of the most recalcitrant species for in vitro regeneration. Conventional coconut breeding has a long lifetime and high heterozygosity, making it a time-consuming, intricate, and costly technique for plant growth. As a result, it is critical to replant most of the world's agricultural land and to develop new soil. This massive undertaking will necessitate planting at least a billion coconut palm trees, which cannot be propagated by seed. Somatic embryogenesis, as a biotechnological alternative, is thus required. Work on this subject has been done in laboratories in numerous countries, with different techniques and explant shapes being investigated. The zygotic embryos are more effective in initiating the callus induction fortified on C1 and C2 formulations added with activated charcoal, gelling agent, and hormone 2, 4- dichlorophenoxyacetic acid (2,4- D). The study has observed that the C1 media successfully initiated callus formation, but the C2 media allowed embryogenic calluses and somatic embryos to develop. From this study, the seedling and regenerated callus were growing well on C3 media. Mature coconut plantlets were acclimated using a combination of sphagnum, sand, and soil mix. The plantlets, on the other hand, could not adapt to their circumstances.