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The vetiver is an excellent source for essential oil, fodder, thatching, handicrafts, and mulching. Besides its various utility, a limited study has been done as fodder for ruminants. The major studies in the vetiver were focused on oil production, soil/water conservation. The study related to livestock cattle feeding on vetiver is very meager. The essential oil content, yield, nutritional, and protein quality of the fodder are highly affected by the G × E interaction. Objectives were to determine the extent of genotype × environment interaction for the nutritional quality of fodder, oil yield and to identify stable genotypes for the future breeding program. The thirty lines were evaluated to meet the above objectives to select genotypes with high oil yield and fodder quality. The genotypes were planted in RBD at the Institute in three years. The observations were recorded on twenty traits. The roots were distilled for oil by hydro-distillation for 24 h. GC analysis was performed in a Varian CP 3800 system using an Elite-5 fused silica column (30 m × 0.25 mm × 0.25 μm). The pooled mean observations of all characters were analyzed for stability by the GGE biplot. For after the pooled ANOVA across years, all the twenty traits showed highly significant variations except four. Except for one variable, essential oil content, genotype was very significant for all twenty traits (%). For maturity stage × year interaction, all the twenty traits also showed high significance except four traits. For the maturity stage × genotypes interaction, all the twenty traits also showed highly significant variations except four traits. For years × genotypes interaction, all twenty traits also showed highly significant differences. For the maturity stage× years × genotypes interaction, all the twenty traits also showed high significance except one trait. The genotype Vg-11/selection 24 expressed the highest performance for eight traits: digestibility, protein, potassium, phosphorus (%), iron, copper, and manganese (mg/Kg) in vetiver leaves and the root yield/plot (g). The genotype Vg-15 for the three traits: calcium (%), khusinol, and β-vetivone (%) in essential oil. Despite the importance of essential oil, its leaves are vital due to their nutritional quality and can be used as fodder. Genotype Vg-11/selection 24 may recommend as a suitable and nutritious fodder and Vg-13 for high oil. The vetiver also has a perfect opportunity to be as nutritious fodder in livestock for nutrition and production.

Conventional breeding can be complemented by different strategies that increase the efficiency of the methodologies and the current rate of increase in yields in order to meet demand. The use of molecular markers with the aim of developing linkage maps of the species, the use of Blup (Best Linear Unbiased Prediction) for an efficient selection of progenitors to hybridize, the use of in vitro culture to artificially increase the number of F1 plants or the use of digital phenotyping for efficient digital characterization that can be performed during the periodic and routine regeneration of accessions in germplasm collections. Key words: Molecular markers, Blup, in vitro culture, digital phenotyping.

Mung bean (Vigna radiata L. Wilczek) is an important annual legume which is well suited to dry areas, like Burkina Faso where it is still an orphan legume. The present study was conducted to evaluate 44 mung bean genotypes introduced in Burkina Faso and to determine genetic diversity in this collection using both quantitative and qualitative traits. A field experiment was conducted in an augmented bloc design with three blocks and an extraearly maturing cowpea variety as check. Data were recorded on six (06) quantitative traits and seven (07) qualitative traits. For qualitative traits, diversity was revealed in four parameters including hypocotyl’s color, seed coat color, pods and stem pubescence. Significant genetic variability was revealed among genotypes for all the quantitative characters. Phenotypic coefficient of variation (PCV) was higher than Genotypic coefficient of variation (GCV) for all characters studied indicating the influence of environmental effect on the characters. The GCV and PCV estimates were high for number of pods per plant followed by plant height and hundred seeds weigh. The high heritability coupled with high genetic advanced as percent of mean observed for these traits suggest an important genetic gain in genetic improvement for these characters. The genetic diversity observed was grouped into five clusters. Mungbean lines were grouped into four clusters and the cowpea variety used as check crop in this trial was clustered apart. This gbiodiversityenetic diversity, both qualitatively and quantitatively, will help enrich local in terms of legumes in general and mung bean in particular and constitutes an important basis for a future mungbean breeding program.

The adoption of new and high yielding pearl millet (Pennisetum glaucum (L.) R. Br.) varieties can be boosted if they correspond to farmers’ preferences and answer the constraints prevailing in the production environments. Therefore, the focus of this study was to assess production constraints, farmers’ preferences and choices of varieties among pearl millet cultivating farmers using participatory rural appraisal (PRA) in the guinea savanna agro-ecological zone of Ghana where the crop is grown. Data collection was through mixed methods of focus group discussion (FGD) and individual interviews with 295 (45 for FGD and 250 for individual interviews) farmers covering 45 communities. Results indicated that the major constraints of production included low yields, bird damage, poor soils, erratic rainfall, downy mildew disease, head insects, and early maturity. Majority of pearl millet farmers depend on own seed source due to lack of access to and low knowledge of improved seeds. Breeding for high grain yield, earliness, resistance to downy mildew disease and bird attack varieties were the leading traits of preference that research should focus on. It is therefore anticipated that breeding program would integrate the product profiling proposed in this work for enhance adoption of new pearl millet varieties in Ghana. Key words: Participatory rural appraisal, constraint, pearl millet Guinea savanna, Ghana.

Background In recent years, farmers have complained that the only way to obtain seeds is to select plants that show good performance under local climate conditions in the region. This study aimed to investigate the diversity of rice accessions grown in the region to build a breeding program. Methods and results A total of 62 accessions of rice from farmers and research stations were collected from the Kurdistan region, including short-grain and long-grain types, for molecular genetics and diversity analysis. In this study, 37 polymorphic simple sequence repeat (SSR) markers were selected with several molecular genetics software programs. The results show that these SSR markers are very effective for this investigation, generating a total of 152 observed alleles (Na), 75.166 Effective number of alleles (Ne) and an average of 4.1 and 2.03 alleles per locus, respectively. The average polymorphic information content (PIC) per locus was recorded as 0.404. The research presented here confirms two subpopulations, japonica (C1 and C2) and indica (C3), based on molecular genetics data analysis. Analysis of molecular variance revealed that the 72% variance was due to the variation among populations and 28% within the population. Conclusions Altogether, these results indicate that there is very low gene flow. These results show the importance of the study of genetic diversity and relationships for starting breeding and improvement programs for rice in the Kurdistan region. Supplementary Information The online version contains supplementary material available at 10.1007/s11033-021-06920-x.

Sugarcane (Saccharum spp. hybrids) is one of the world’s most important economic crops for both the food and biofuel industries. It has one of the most complex genomes of any crop plant, varieties are unbalanced polyploids and derived from interspecific hybridisation between the domesticated Saccharum officinarum and a wild relative S. spontaneum. Here I review sugarcane’s complex genetics and chart the history of DNA marker development in sugarcane over the last 30 years. Despite its complex autopolyploid genome of over 100 chromosomes, marker development has spanned the first hybridisation-based markers, restriction fragment length polymorphism markers (RFLP) to the high-throughput next generation sequence methods currently used to detect single nucleotide polymorphism (SNP). Although there is a long history of research and development in sugarcane, it is only comparatively recently that marker technology has caught up with the need for discovery of large numbers of single-dose SNP markers and methods for genotyping that are fast, efficient and cost-effective that can be used for selection in a breeding program. The choice of genotyping platform depends on the breeding application and both whole genome SNP methods (array-based and genotype-by-sequencing (GBS)) and low density scalable and cost-effective platform technologies have a place in sugarcane breeding.

Sugarcane is the most important sugar crop in China. In this paper, we reviewed advances in sugarcane breeding, germplasm development and breeding-related molecular research in China. From the 1950s to now, much progress has been made in China in the collection and evaluation of sugarcane germplasm, variety selection techniques and biotechnology. A total of 3300 Saccharum and related species are preserved in the China National Nursery of Sugarcane Germplasm Resources, in Kunming, Yunnan province. Through intra- and interspecific crossing between Saccharum spp. and related species, successful introgression of genes from wild germplasm including S. spontaneum, Narenga porphyrocoma, Erianthus rockii, and Erianthus fulvus has been achieved. Imported elite clones from major international sugarcane breeding programs remain an important source of parental material for variety development. A series of clones derived from innovative crosses at Hainan sugarcane breeding station with native Chinese S. spontaneum germplasm have been important parents in Chinese breeding program, leading to release of 37 commercial cultivars. Transgenic sugarcane clones with insect and disease resistance, and drought and low potassium-tolerance were also created. However, its use in commercial production remains unclear at this stage. Recently Chinese researchers published the first report of S. spontaneum genome, which is providing substantial new knowledge and unprecedented genomic resources for the genetic improvement of sugarcane. Through the efforts of breeders and researchers, the yield, sucrose content and disease resistance of sugarcane in China have been improved greatly. The current major constraints in the sugarcane industry in China are the low level of mechanized harvesting, poor ratooning and diseases such as smut, and sugarcane borer. Developing production systems and varieties suited to mechanized harvesting, resistant to smut and increased ratooning are now a high priority.

The availability of mungbean (Vigna radiata) genetic resources is important in breeding programs for development of new improved varieties. The objective of this study was to describe the characters of 300 accessions of ILETRI’s mungbean genetic resources collections. The study was conducted in Jambegede Experimental Station, East Java, Indonesia during dry season 2018. The results showed that the descriptive characters of 300 mungbean germplasm accessions had a fairly wide range, namely 50%-flowering date ranged from 30-50 days after planting with an average of 41.92 days, Pod maturity ranged from 50 - 88 days after planting with an average of 74.08 days, 100-seed weight ranged from 2.43 to 7.96 g with an average of 4.52 g, and Seed weight per plot ranged from 10 - 525 g with an average of 254.53 g. There were three accessions with seed size more than 7.5 g/100 seeds, namely MLGV 0713, MLGV 0960, and MLGV 1027. These accessions could be used as a source of genes for developing high yielding and large seed size of new improved mungbean varieties. Furthermore, the high diversity data in mungbean collection can provide information to used by breeders.

Leaf scald caused by Xanthomonas albilineans in sugarcane is one of the most important diseases around the world since it causes severe losses in both agricultural and industrial yields. In Cuba, resistance to this disease is considered a major selection criterion within the breeding program. The aim of this work was to detect sugarcane cultivars with stable reaction to X. albilineans by using both additive main effects and multiplicative interaction (AMMI) and linear general models. For this, 16 cultivars planted simultaneously in 2015, 2016, and 2017 in two locations: Jovellanos (Matanzas) and Florida (Camaguey) in Cuba were mechanically inoculated with a bacterial isolate previously characterized by sequencing its DNA fragment. Disease severity was recorded in plant cane and first ratoon, and results were consistent in both analyses and revealed that L55-5 and C323-68 were the most susceptible cultivars and C1051-73 was the most resistant; however, C1051-73, C275-80, C86-12, C88-382, C89-147, My5514, and Ty86-28 were the most stable across the years and localities evaluated. Results will allow adapting the methodology for the evaluation of the reaction to leaf scald of new sugarcane cultivars.

Variance components and heritabilities for daily weight gain (DWG) were estimated for Nile tilapia farmed in cages across nine generations (G1-G9) of selection in a breeding program in Brazil. DWG was measured in 16,272 accumulated tagged animals representing 535 full- and half-sib families of Nile tilapia under cage farming. The additive genetic variance showed a slight variation (0.051-0.066), and heritability estimates ranged from 0.20 to 0.33. The common environmental effect accounted for a higher proportion of the total variance in DWG, especially in the last generations (6%-24%). A genetic trend based on all data available showed a substantial increase in the DWG (about 3.3% per generation) of Nile tilapia across nine generations of selection. Furthermore, our results demonstrate ample scope for further genetic improvement.

Identification and characterization of leaf and neck blast resistant varieties in terms of number of resistance genes and their allelic relationship is a pre-requisite for any breeding program to breed resistant cultivars. Genetics of pathotype specific field resistance was studied in six resistant genotypes against leaf and neck blast pathogen (Pyricularia oryzae). Crosses were attempted in half diallel fashion among themselves and with susceptible parents during Kharif 2017 and 2018. Parents, F1 and F2 generations were evaluated for leaf and neck blast reaction under artificial epiphytotic conditions. Based on the disease reaction of F1 and segregation pattern in F2 populations in Resistant (R) × Susceptible (S) and Resistant (R) × Resistant (R) crosses, it was observed that resistance in genotypes HPR 2880, HPR 3001, HPR 3007 and Kasturi were governed by two independently inherited dominant resistance genes whereas, three resistance genes conferred resistance in genotypes HPR 1156 and HPR 3010 for both leaf and neck blast. Segregation pattern in F2 populations in R × R crosses suggested that resistance genes for leaf and neck blast have at least one common allele in genotypes, HPR 2880, HPR 3001, HPR 3007 and Kasturi which are different from the genes identified in genotypes, HPR 1156 and HPR 3010.

An olive breeding program was started in Tunisia in 1993 in order mainly to improve the fatty acid composition of the local cultivar ‘Chemlali Sfax’. ‘Zeitoun Ennour’ is a new cultivar obtained from a cross between ‘Chemlali Sfax’ and the local dual-purpose use cultivar ‘Chemchali Gafsa’. The morphological study of this cultivar showed that eleven characters dealing with fruit and endocarp differed from ‘Chemlali Sfax’, mainly regarding to their respective weights. This new cultivar had the same sensitivity to Verticillium dahliae Kleb and earlier bearing than the original variety. Its olive production was considered as high as for ‘Chemlali Sfax’ but with partial self-compatibility and late maturity. The new cultivar realized a net improvement in comparison with the original cultivar particularly regarding its fatty acid composition with very high oleic acid content (>75 %) and low palmitic and linoleic acid contents (

The crested ibis has survived a dramatic population decline during the twentieth century, declining from a range across much of China, Japan, the Korean peninsula and nearby Russia, to a known world population of seven individuals. These formed the basis of a successful breeding program in Shaanxi, China. We examined ibises in this breeding program for ectoparasites, to establish whether any of the three chewing louse species known from this host had survived this severe host population bottleneck. We recovered representatives of three species of lice, identified as the same species as those previously known from the wild populations: Ardeicola nippon, Colpocephalum nipponi, and Ibidoecus meinertzhageni. Of these, the two first species were recovered from almost all examined hosts, whereas I. meinertzhageni was more rare. As these lice are host specific, this implies that all three louse species remarkably survived this bottleneck, and are now thriving in both the reintroduced and captive populations of crested ibis. This constitutes an unintentional success story in the conservation of parasitic species. We provide the first photos of all three species, as well as a preliminary assessment of their conservation status, and discuss the future of chewing louse conservation.

The productivity of tomato in Nepal is very low due to lack of high yielding, disease and pests resistant varieties. An experiment was carried out to evaluate horticultural traits of 50 genotypes obtained from World Vegetable Centre (WorldVeg), Taiwan and SAARC region, and local collections during March to August 2020 in open field conditions at National Horticulture Research Centre, Khumaltar, Lalitpur. The objectives were to identify promising open-pollinated tomato cultivars for high yield, appropriate fruit size, and disease resistant. The experiment was carried out in a randomized complete block design with three replications. Results showed significant differences in yield and yield attributing characters including virus infection. The highest yield (39.6 mt ha-1) was produced by HRA43 and it was followed by HRA33 (26.4 mt ha-1). Among the WorldVeg OP lines, AVTO1429 produced the highest yield (16.21 mt ha-1) and it was followed by AVTO1717 (12.95 mt ha-1), AVTO0922 (11.83 mt ha-1) and AVTO1219 (11.7 mt ha-1) respectively. Most of the WorldVeg lines performed better than the check variety ‘Pusa Ruby’. Genotype HRA43, Red Local and Sindhupalchock Local were not affected by virus while Yellow Local showed 3.3% infection. Among the WorldVeg lines, AVTO1712 (20%), AVTO1717 (20%) and AVTO1718 (13%) and AVTO1219 (15%) showed less than 20% virus infection in the open field conditions. Cluster analysis using the unweighted paired group method with arithmetic mean showed that cluster-1 was the largest cluster comprised of 40 genotypes followed by cluster-2 and cluster-4. Genotypes from cluster-4 showed the higher fruit yield (25.1 mt ha-1) and resistant to the virus and the highest number of fruits per plot (1978 in 4.5 m2 area). The yield was low in cluster-1 which could be due to the heavy rainfall during the vegetative and reproductive stages. Genotypes Red Local and Sindhupalchock Local could be used in future tomato breeding program due to their resistant to TYLCV, higher potential yield and highest plant vigour in open field conditions at the mid-hill of Nepal. Considering the overall performance, genotype HRA43, HRA33 and AVTO1429 were promising lines with performance for yield and other horticultural traits.

Breeding program strategies to develop novel short grain white rice varieties such as japonica (short grain) that introgress biotic stress resistance and high grain quality have been developed using indica rice (Pin Kaset + 4 and Riceberry) for applications in japonica rice (Koshihikari) improvement. Four breeding lines showing promising agronomic performance with short grain and low amylose content (< 20%) were obtained. In addition, sensory testing of these breeding lines showed high scores that similar to Koshihikari. Two promising lines, KP48-1-5 and KP48-1-9, which possessed a combination of four genes resistance to different biotic stresses (Bph3 + TPS + Xa21 + Pi-ta) and four genes for grain quality (GS3 + SSIIa + wxb + badh2), were developed using marker-assisted selection (MAS) with the pedigree method. The current study clearly illustrated the successful use of MAS in combining resistance to multiple biotic stresses while maintaining a high yield potential and preferred grain quality. Moreover, the results indicated that this breeding program, which includes crossing temperate japonica with indica, can create novel short grain rice varieties adapted to a tropical environment, like the japonica type.

The oil palm breeding program for the species Elaeis guineensis and the backcross Elaeis oleifera is running slowly because oil palm is an annual plant. Therefore, it is necessary to have an alternative approach that can accelerate the oil palm breeding program. The SNP (single nucleotide polymorphism) genome-wide approach was then used to study the association between 18 phenotypes of bunch component in oil palm germplasm of E. oleifera from Suriname and Brazil Coari, some interspecific hybrids and some elite progeny of E. guineensis. The genotyping by sequencing (GBS) analysis produced a total of 459 million or approximately 798 thousand reads per sample and 3,252 SNPs were eligible for 456 genotypes. Using various association models, eleven normalized phenotypic data showed significant associations with 29 SNPs. Based on the annotations, 17 SNPs were related to genes wtih certain biological functions. Three SNPs were found to be at the exon of a gene, namely SNP4416, SNP349 and SNP3865, while the other 15 SNPs were at the intragenic to a gene. Four SNPs are common SNPs in phenotypes C16:0 and C18:1 as weel as in C20 0 and C20:1. This research shows the potential of SNPs that can be used as an alternative approach to E. oleifera backcross breeding, although further research is needed for validation purposes.

Scarlet eggplant (Solanum aethiopicum gr. gilo) is a part of African indigenous vegetables and acknowledged as a source of variations in the breeding of Brinjal. Since its genetic diversity is still largely unexplored, therefore genetic diversity and population structure of this plant were investigated in this study. Scarlet eggplant germplasm made of fifty-two accessions originated from two districts of Rwanda was assessed by employing the iPBS-retrotransposon markers system. Twelve most polymorphic primers were employed for molecular characterization and they yielded 329 total bands whereupon 85.03% were polymorphic. The recorded mean polymorphism information content was 0.363 and other diversity indices such as; mean the effective number of alleles, mean Shannon’s information index and gene diversity with the following values; 1.298, 0.300 and 0.187 respectively. A superior level of diversity was noticed among accessions from Musanze district. The model-based structure, neighbor-joining, and principal coordinate analysis (PCoA) gathered scarlet germplasm in a divergence manner to their collection district. Analysis of molecular variance (AMOVA) displayed that the utmost variations (81%) in scarlet eggplant germplasm are resulting in differences within populations. The extensive diversity of scarlet eggplant in Rwanda might be used to form the base and genetic resource of an exhaustive breeding program of this economically important African indigenous vegetable. For instance, accessions MZE53 and GKE11 might be proposed as parent candidates due to their high relative genetic distance (0.6781).

In silico is the more comprehensive and applicable approach in supporting, both conservation and breeding programs of germplasm. The study aimed to analyze and determine the genetic diversity and relationships of 24 species of Phalaenopsis using two DNA barcoding markers, namely the rbc L and trn L-F, by in silico approach. All sequences of these markers were collected randomly from the NCBI website and analyzed using several softwares and methods, such as ClustalW and MultAlin for multiple sequence alignments and MEGA-X to determine its genetic diversity and relationships. Specifically, the genetic diversity was determined using a nucleotide diversity index and their relationships by the Maximum Likelihood method. The results showed that Phalaenopsis has a low genetic diversity of 0.24, 0.32, and 0.19, respectively. The phylogenetic analysis revealed that this orchid separated into five (for the rbc L), six ( trn L-F), and seven clades (a combined one), where the closest relationship is shown by P. amboinensis vs. P. venosa , whereas the farthest by P. gibbosa vs. P. doweryensis , P. stuartiana vs. P. micholitzii , and P. celebensis vs. P. pulchra . The results have novel information on the diversity and relationships of Phalaenopsis on the in silico approach. Thus, our findings might be used in supporting the conservation and breeding program of Phalaenopsis , both locally and globally.

The scarlet eggplant (Solanum aethiopicum L.) is an African traditional vegetable grown for its edibles leaves and fruits, which can contribute to food security in Republic of Benin. However, very little information is available on the genetic variability of this vegetable for varietal improvement purposes. Sixty accessions of scarlet eggplants collected throughout 52 villages in Benin republic were characterized using 34 (10 qualitative and 24 quantitative) variables. The experiment was laid out using complete randomized block design with three replications on the experimental site of Massi. The Principal Component Analysis (PCA) analysis revealed 18 discriminating quantitative variables. A strong correlation was observed between plant height, number of fruits per plant, fruit diameter, fruit weight and number of seeds per fruit. A cluster phenogram divided the 60 accessions into three groups corresponding to Kumba (Cluster 1), Gilo (Cluster 2), and Shum groups (Cluster 3). These groups differed by the number of seeds per fruit, weight of fruits, diameter of fruits, number of fruits per plant, plants height at flowering stage, plants length, and plant width. Accessions Samibi, Ikangougou, Kannan and Yetchanmiye with the highest fruit weight per plant can be used as parents in the framework of a scarlet eggplant breeding program in Republic of Benin. Key words: Benin, accessions, traits diversity, breeding program.

Black wattle (Acacia mearnsii) has great economic value as a commercial source of tannins, timber and a source of firewood for local and international markets. It has been suggested that to maximize the genetic gain of A. mearnsii plantations in South Africa, the gene pool that exist within ICFR needs to be broadened via introduction of new genotypes with diverse traits. In this work, 282 A. mearnsii samples sourced from the ICFR breeding program were genotyped using 11 cross-species SSR markers. Our results showed low to moderate genetic differentiation (FST) among the six breeding subpopulations, with positive inbreeding (FIS) values that could be attributed to an historical inbreeding event. Low levels of relatedness could however indicate some mechanism of inbreeding avoidance. The effects from a recent supplementation of genetic material from two native Australian populations were observed through genetic structuring analyses. Analysis of molecular variance (AMOVA) revealed that significant genetic variation was mainly distributed within populations (75%) and among individuals (23%). The results provide significant information on A. mearnsii population genetic diversity and structure, which can be used for conservation of the current subpopulations and future tree improvement programs.

Breeding activities of Acacia mangium have been established to the second breeding generation (F2) in Wonogiri, Central Java, Indonesia, in order to increase stand productivity and the quality of timber products. However, research on wood properties of A. mangium in breeding program is still limited in Indonesia. This study aims to determine the properties of wood, especially the physical and mechanical properties of three breeding generations (F0, F1, and F2) of A. mangium wood. Furthermore, relationship between air-dried density and mechanical properties was also clarified. As a result, the physical and mechanical properties of wood are not significantly different among three generations, indicating that this breeding activity did not affect a significant decrease in the physical and mechanical properties of A. mangium wood. In addition, air-dried density has significant correlation with all mechanical properties measured.

Shell color is regarded as an economic trait in many breeding programs of bivalve mollusks, but the relationship between shell color and production traits remains controversial. In our breeding program of Crassostrea gigas, solid white, black, and orange shell lines were obtained, and second-generation (F2) and testcross families with segregating shell colors were constructed by crossing these three lines. These segregating families provided ideal samples for investigating the relationship between shell color and production traits in C. gigas. The growth and survival of 7-month-old oysters with different shell colors sampled within the same families were compared in seven F2 families and 13 testcrosses. In addition, the growth and survival of oysters from the three shell color lines were compared at 4 and 16 months of age. The growth and survival rates of the orange shell line were significantly lower than those of the white and black shell lines. However, no significant difference in growth between oysters with different shell colors was observed within segregating families, except the testcrosses produced by crossing orange- and white-shelled grandparents, and no significant difference in survival was observed in any family. Overall, no significant correlation was observed between shell color and production traits in C. gigas. These results suggest that shell color cannot be used as a marker to guide the selection of growth and survival traits. Thus shell color and production traits should be selected independently in oyster breeding programs.

Iran is considered as one of the main centers of diversity of spinach species and one of the biggest producers, worldwide. However, there is no comprehensive information on the chromosomal characteristics of its wild species and the possible association of these indices with morphological and physiological features. The present study was conducted to analyze these characteristics in different populations of Iranian wild spinach compared to a commercial cultivar (Spinacia oleracea cv. Viroflay). The results showed that the seven spinach populations studied were diploids (2x = 2n = 12), and interestingly, the most of observed chromosomes were sub-metacentric. In case of morphophysiological traits, significant differences were observed for the most of measured traits and all morphological traits except number of leaves were higher in domestic species than the other two wild species. The results of physiological traits showed the highest content of anthocyanin and total chlorophyll, respectively, in Spinacia oleracea and S. tetrandra, and there was no significant difference among studied species for carotenoids content. In addition, the correlation coefficients showed significant correlations among chromosomal features, morphological characteristics and physiological traits. For example, with increase in the total length and the long arm of chromosomes, the number of leaves was increased and the content of chlorophyll a was decreased. Further, these species could be utilized in the breeding program to develop high yielding genotypes.

Background. Stem rust of wheat, caused by the biotrophic fungus Puccinia graminis Pers. f. sp. tritici Eriks. et Henn., is a dangerous disease that afflicts serious economic damage to the cultivation of durum wheat.Materials and methods. Cultivars and promising materials developed at the Spring Durum Wheat Breeding Laboratory, Omsk Agrarian Scientific Center (OASC), lines obtained under the CIMMYT and KASIB programs, and accessions from the VIR collection were the objects of research. Field experiments, phenological observations, and assessment of stem rust resistance were carried out from 1990 through 2019 in the OASC experimental fields using conventional methods. Resistance to the Ug99 race was evaluated under natural infection pressure at the Kenya Agricultural and Livestock Research Organization (KALRO).Results. Promising source material was identified and included in the Laboratory’s breeding program. The ways were shown to develop stable cultivars of spring durum wheat for the environments of Western Siberia. A strategy was proposed for the selection of genotypes in hybrid combinations of spring durum wheat: it would include early selection (starting from F2 ) for disease resistance with simultaneous screening for quantitative traits and pasta-making qualities. The description and advantages of cv. ‘Omsky korall’, submitted to the State Variety Trials in 2018, are presented. This cultivar combines high yield, adaptability, resistance to the local population and the Ug99 race of the stem rust pathogen, and excellent pasta-making qualities.Conclusion. As a result of these studies under heavy stem rust pressure in Western Siberia, all breeding nurseries obtained source material resistant to the Omsk population of P. graminis. The released cultivars ‘Omskaya yantarnaya’ and ‘Omsky izumrud’ demonstrate resistance to the Omsk population of the stem rust causative agent.

Relevance. F1 hybrids breeding programs of onion are based on the use of nuclear cytoplasmic male sterility (NCMS). Breeding and seed production based on NCMS suggest a development of a female sterile maternal line, a maintainer line and a paternal component. The development of an isogenic pair of sterile line – maintainer line is one of the most labor-, time-consuming and intellectually-intensive stages of a breeding program, the implementation of which becomes more complicated with an increase in the number of traits / genes for which selection is carried out.Methods and results. This paper presents a genetic scheme for the development of a Downy mildewresistant (pathogen P. destructor) maintainer line of onion using marker-assisted selection (MAS). F2 populations were obtained from the cross of the female maintainer inbred line, Bn1- (13) (genotype – cytN msms pdpd) and male inbred line resistant to Downy mildew, No. 136 (genotype – cytT MsMs PdPd). DNA marker DMR1 were used for Downy mildew resistance gene Pd, jnurf13 – for maintainer gene ms and marker system 5`cob: orfA501 – for N, S and T cytoplasms. It was shown that the MAS application allow to develop a stable Downy mildew resistant maintainer line cytN msms PdPd in two generations.

Sugarcane has been cultivated in Egypt since 641 AD and is a source of raw material to various agro-based industries. The development of new varieties of sugarcane from controlled crosses in Egypt has developed greatly during recent decades with the majority of the present commercial varieties originating from the local breeding program. Egyptian sugarcane breeding program objectives are high cane and sugar yield, early maturing, good ratooning ability, resistance and tolerance to pests as well as diseases. This program depends on artificial flowering at Giza Research Station (latitude of 30.01° N and longitude of 31.20° E) and natural flowering at Sabahia Research Station, Alexandria (latitude of 31° 12 N and longitude of 29.57° E). There are four stations for selection trials, extending from middle to southern Egypt, namely Mallawi (Minia governorate), Shandaweel (Sohag governorate), Mattana Station (Luxor governorate), and Kom Ombo (Aswan governorate), respectively. Current sugar production in Egypt is about 2.458 million tons with 62.2% from sugar beet and 37.8% from sugarcane.

The success of any breeding program depends on the ability to determine germplasm diversity and genetic relationships among breeding materials. Genetic diversity is an invaluable aid in crop improvement. This study was carried out to determine the genetic diversity among 70 extra-early yellow maize hybrids under Striga environments. Cluster and principal component (PC) analyses were used to determine the genetic diversity of the hybrids. Data on morphological and agronomical data were collected. The experiment was set up in two locations (Abuja and Mokwa) in a randomized incomplete block design experiment with two replications. A significant difference was observed among the hybrids in all the traits studied and a significant genotype × environment interaction was observed for all traits except for plant height, anthesis silking interval and Striga count at 8 and 10 WAP. The principal component reveals that the first three components account for 86% variability. PC1 gave maximum variability (43%) and was loaded with PC1 and the first four PCs can be utilized in hybridization programs. The principal component biplot reveals the relationship among traits and the distance of each variable in determining variability among hybrids. The cluster diagram reveals five distinct groups. Group IV consisted of Striga tolerant hybrids and group I consisted of susceptible hybrids. Both principal component and cluster analysis revealed the genetic diversity among the hybrids and identified genotypes that were Striga tolerant and could be selected as choice of parental materials to develop Striga resistant materials

Lima bean (Phaseolus lunatus L.) is one of the five most important legume crops from the genus Phaseolus though it is one of the neglected crops in Ethiopia. There is no national breeding program for its improvement. As it is true for all crops, understanding the genetic diversity of Lima bean is useful for its improvement and sustainable use. Therefore, the objective of the current study was to investigate genetic diversity of Lima bean landrace collected in Ethiopia using eight issr markers. A total of 96 landrace were collected from five administrative zones of Ethiopia from which 106 clear bands were detected. About 95 (88.7%) of the bands were polymorphic. The genetic diversity analyses result revealed that landrace collected from West Wellega showed the highest (0.1864) genetic diversity. amova demonstrated highly significant (P=0.00) genetic diversity among and within populations. A considerable proportion (66%) of the total genetic diversity was distributed among populations and 34% within populations. In addition, the calculated Fst value was high (Fst = 0.66), associated with a low gene flow value (Nm=0.27) indicating lower differentiation of the populations, which, in turn, implied no significant exchange of planting materials among farmers in the studied populations and the nature of the crops that Lima bean is 52% self pollinated crop. upgma, structure and PCoA analysis showed very strong grouping among individuals collected from the same zones and geographically distinct zones. Overall, genetic diversity achieved from this study could be used as pioneer information about the existing genetic resource for future Lima bean conservation and improvement strategy in Ethiopia.

Low soil nitrogen (N) is one of the major abiotic stresses reducing maize yield in Africa. Twenty-five maize varieties which included quality protein maize (QPM), drought and Striga tolerant maize, and two low soil nitrogen (LN) tolerant maize as checks, were evaluated in two locations between 2017 and 2018 to identify varieties with tolerance to LN. The field was mopped of nitrogen by planting maize twice without fertilizer and the soil was analyzed before the trial. The experiment was laid out in a randomized complete design in three replications. Urea fertilizer was applied in a split dose at 2 and 4 weeks after planting at rate of 30kgN/ha for low nitrogen (LN) and 90kgN/ha for high nitrogen (HN) plot. Data were collected on days to flowering, anthesis-silking interval, leaf death, grain yield, and other agronomic parameters. Data were subjected to analysis using SAS. Rank summation index (RSI) and cluster analysis were used to select the best varieties under LN. Apart from the two checks, varieties DT STR -Y2 SYN and TZE COMP3 DT had good yield of 1.99 tons/ha and 1.39tons/ha, respectively, under LN, with yield gap of 0 and 44%, respectively. The top ranked varieties under LN using RSI either appear singly or in a group under cluster analysis. They included drought and Striga tolerant varieties along with the two LN checks, implying that Striga tolerant maize also possesses the ability to tolerate LN. The varieties could, therefore, be involved in a breeding program for improvement for low soil nitrogen.

Breeding natural enemies to generate populations with improved characteristics is an attractive idea, particularly nowadays with the increase in use of biological control and the availability of modern molecular and genetic tools. A first step in the process is to characterize traits which can be important for biological control and their intraspecific variation. In this study we characterized fecundity, longevity and dispersal-related traits of four endogamic and three exogamic laboratory populations (lines) of Mastrus ridens, an important parasitoid of the codling moth (Cydia pomonella (L.)). We found that several traits were positively correlated and that there was variability among lines and between endogamic and exogamic lines. Exogamic lines presented a better combination of trait values than endogamic lines. The absence of trade-offs among the traits studied in M. ridens would be advantageous for a breeding program. Nevertheless, it would be important not to lose genetic variability in the process, because of the presence of complementary sex determination (CSD) and negative effects of inbreeding on other traits. The results of this study could be useful for the selection of M. ridens lines with better traits and as preliminary information for breeding programs.

The chicken Major Histocompatibility Complex (MHC) is closely related to resistance to several diseases. Moreover, selection for genetic resistance to diseases is a critical goal in the broiler breeding companies, which should be carefully balanced with different economic traits, including live body weight (LBW) and meat yield. The microsatellite marker LEI0258 is used to evaluate the effect of selection for 12 generations for high LBW at 6 weeks of age (LBW6) with natural selection against Marek disease (MD) on genetic component associated with resistance to MD and Newcastle diseases (ND) in local broiler breeders, Cairo B-2 line, compared to commercial broiler breeder line (AA line). Results indicated that, Cairo B-2 line had lower carcass parts with higher internal organs percentages compared to AA line. In addition, there was a positive association between 473 bp allele of LEI0258 with regard to LBW6 and carcass traits in two lines. Moreover, LEI0258 alleles 357 bp and 295 bp were present with high content in Cairo B-2 line only, which increased the genetic resistance to Marek’s disease and increased the humoral immune response against ND vaccination in Cairo B-2 line compared to AA line. The correlations between these valuable productive traits and LEI0258 microsatellite will effectively assist the selection process by applying Marker-Assisted Selection in Cairo B-2 line breeding program in the future.

We identified cryptic early blight resistance introgressions in tomato breeding lines and demonstrated efficient genotypic selection for resistance in the context of a tomato breeding program. Early blight is a widespread and problematic disease affecting tomatoes (Solanum lycopersicum). Caused by the fungal pathogen Alternaria linariae (syn. A. tomatophila), symptoms include lesions on tomato stems, fruit, and foliage, often resulting in yield losses. Breeding tomatoes with genetic resistance would enhance production sustainability. Using cross-market breeding populations, we identified several quantitative trait loci (QTL) associated with early blight resistance. Early blight resistance putatively derived from ‘Campbell 1943′ was confirmed in modern fresh market tomato breeding lines. This resistance offered substantial protection against early blight stem lesions (collar rot) and moderate protection from defoliation. A distinctive and potentially novel form of early blight foliar resistance was discovered in a processing tomato breeding line and is probably derived from S. pimpinellifolium via ‘Hawaii 7998’. Additional field trials validated the three most promising large-effect QTL, EB-1.2, EB-5, and EB-9. Resistance effects for EB-5 and EB-9 were consistent across breeding populations and environments, while EB-1.2’s effect was population specific. Using genome-wide marker-assisted backcrossing, we developed fresh market tomato lines that were near-isogenic for early blight QTL. Resistance in these lines was largely mediated by just two QTL, EB-5 and EB-9, that together captured 49.0 and 68.7% of the defoliation and stem lesion variance, respectively. Our work showcases the value of mining cryptic introgressions in tomato lines, and across market classes, for use as additional sources of disease resistance.

Coffee is the stimulant crop plant that belongs to the genus Coffea, in the family Rubiaceae. The yield variation and pattern of the crop varied within short geographic distance and thus attributed to low productivity and unpredictable production. The objective of this study was to determine the extent of genotype × environment interaction on yields of promising Teppi coffee genotype. In this study, seventeen Arabica coffee genotypes, representing coffee growing areas of Teppi, southwestern Ethiopia were evaluated at six environments. This study was conducted by using completely randomized block design with two replications. The extent of genotype × environment interaction was analyzed by using additive main effect and multiplicative interaction model and genotype main effect and genotype × environment interaction biplot analysis model. The analysis of variance for yield revealed the presence of highly significant differences ( P < 0.01 ) within genotypes, environments and genotype by environment interaction. From the total sum of squares of genotype × environment interaction of yield, environment accounted for 51% while genotypic and GEI effects were 20.5% and 25.32%, respectively. Generally, genotypes with superior performance and suitable environments for coffee were identified. However, further researches have to target hybridization of those superior genotypes with elite lines in feature Arabica coffee breeding program.

Cherax quadricarinatus is a decapod crustacean of interest to the aquaculture industry. In Mexico, a significant effort has been made to improve biological requirements, but the genetic characteristics are unknown. We examined the genetic diversity and differentiation in four populations in Mexico (three commercial farms and one feral population), as well as one research line from Argentina, used as reference. To initiate a founder stock in a genetic improvement program, we analyzed five microsatellite markers. The genetic diversity in terms of the number of alleles was low to moderate (2.8-6.2) in Mexican populations than the Argentinean sample (8.8). A pairwise Wright's Fst analysis showed that all populations were significantly different (P < 0.5). Cross-breeding organisms from a different population are suggested to increase genetic variability before initiating a founder stock with higher genetic variation.

Yellow passion fruit cultivation in Colombia lacks detailed genetic studies that allow the establishment of intraspecific variability as a basis for a breeding program. The aim of this research was to establish the genetic relationships among accessions of different geographic origins through an agro-morphological characterization. This research was carried out in the municipality of Palestina (Caldas) at the Luker farm located at 1050 m a.s.l. Fifty-two accessions from Colombia (47), Ecuador (3), Brazil (1), and Costa Rica (1) were characterized with 45 agro-morphological descriptors complemented with phytosanitary evaluations. The quantitative descriptors (25) were analyzed by variance decomposition and principal components (PCA), and the qualitative descriptors (18) were analyzed with the multiple correspondence factor analysis (MCFA). The classification analysis by the neighbor-joining (NJ) method was used for both types of descriptors. PCA results showed six components explaining 71.6% of the total variance that are mainly associated with descriptors related to the size of the flower (tube, nectar camera, and operculum) and weight of the fruit (pulp, shell, and juice content). Thirteen qualitative descriptors were selected, and four factors (44.38% inertia) were identified, mainly associated with pubescence and anthocyanins in the bract, petiole, leaf, and ripe fruit color. The NJ classification analysis showed no relationship between accessions by geographic origin, and the distance between individuals of the same accession was higher than among accessions for both types of descriptors. Thrips (Neohydatothrips signifier) and scab (Cladosporium cladosporioides) were the pests with the highest incidence in the accessions. Six elite accessions were identified according to the selection index with outstanding fruit quality characteristics, yield, and tolerance to phytosanitary problems. The high intra-accession variability and traits of certain accessions are the basis for future breeding programs to obtain more productive and tolerant cultivars.

Hama Thrips parvispinus merupakan salah satu faktor pembatas dalam sistem produksi bunga krisan. Penggunaan tanaman genotipe tahan merupakan salah satu upaya pengendalian hama T. parvispinus pada krisan yang ramah lingkungan. Penelitian ini bertujuan mengetahui ketahanan beberapa genotipe krisan mutan Balai Penelitian Tanaman Hias (BALITHI) terhadap hama spesies T. parvispinus. Penelitian dilaksanakan di rumah lindung Instalasi Penelitian dan Pengkajian Teknologi Pertanian (IP2TP) BALITHI Segunung dari bulan Januari sampai Desember 2019. Sebanyak 10 genotipe krisan mutan BALITHI dan 2 genotipe introduksi (Fiji Kuning dan Fiji Putih) digunakan dalam penelitian dengan Rancangan Acak Kelompok 3 tiga ulangan. Metode skrining menggunakan hama T. parvispinus. yang ada di alam atau tanpa investasi. Variabel pengamatan meliputi intensitas serangan hama, persentase serangan hama, persentase bunga layak panen, dan diameter bunga. Hasil penelitian menunjukkan krisan mutan BALITHI Mayang Ratih agak tahan terhadap hama Thrips ini dengan rata-rata intensitas dan persentase serangan hama paling rendah serta bunga layak panen tertinggi serta diameter bunga memenuhi syarat sebagai bunga krisan potong tipe standar. Genotipe Mayang Ratih selanjutnya dapat direkomendasikan sebagai tetua tahan T. parvispinus. untuk program pemuliaan bunga potong krisan. Kata kunci: bunga, Dendrathema grandiflora, hama, intensitas serangan

Paspalum notatum Flugge (bahiagrass) is the most important forage grass in the native grasslands of southern Brazil; the native germplasm is tetraploid and apomictic. Breeding to produce cultivars has been possible due to chromosome doubling of sexual diploid accessions, allowing hybridizations with apomictic genotypes, generating progenies with variability for agronomic traits and segregating for reproduction mode. The aim of this study was to determine the reproduction mode of selected hybrids derived from intraspecific crosses through cytoembryological analysis and to evaluate the level of apospory expres¬sivity. Eighty one tetraploid hybrids corresponding to 21 families of sexual and apomictic parents were generated and 28 most productive plants based on their superior agronomic performance in the field were evaluated. Sixteen hybrids were reproduced sexually and 12 of them were highly apomictic or facultative apomictic. Sexual hybrids may be used for further crosses in the breeding program while highly apomictic plants produce uniform progeny and become candidates of new cultivars to promote pasture diversification. Key words: Aposporous apomixis, bahiagrass, intraspecific crosses, plant breeding.

Spot blotch, an important foliar fungal disease caused by Bipolaris sorokiniana (Sacc.) Shoemaker [stat. anam.], is the influential production restraint over the global wheat-growing regions. A set of eight diverse wheat genotypes including a few breeding lines from Uttar Banga Krishi Viswavidyalaya and commonly accepted susceptible cultivars were screened for spot blotch disease and grain yield across five different locations in West Bengal, India, under environments for natural disease infestation in post-rainy seasons of 2018–2019 and 2019–2020. The present investigation revealed significant variation among the genotypes for spot blotch resistance in different environments as a result of genotype main effect and genotype environment interaction. This study also recorded two genotypes as resistant against spot blotch disease over the five locations. Identified resistant genotypes increased grain yield as a consequence of resistance offered against spot blotch disease suggesting the possibility of considering disease resistance as a must-have trait in all the wheat cultivars that could be identified for cultivation in the North-Eastern Plain Zone of India. Two genotypes resistant to spot blotch recorded 1.26–1.46 times higher grain yield over control under disease pressure that can be recommended for identification and exploited in a resistance breeding program for wheat spot blotch disease-prone region.

The implementation of fish breeding programs in Brazil has brought significant results in the productivity of tilapia. However, the insertion of native species with great potential (such as Tambaqui Colossoma macropomum) in these programs is still recent, and thus requires genetic information for monitoring and enabling their consolidation into the programs. The objective of the present study was to evaluate the genetic diversity of the parental generation (G0) and two consecutive generations (G1 and G2) in the C. macropomum genetic improvement program, located in the municipality of Sorriso, Mato Grosso, Brazil. Ninety caudal fin samples were collected (30 samples per generation) for DNA extraction. The genetic study implemented seven microsatellite markers (Cm1A8, Cm1A11, Cm1D1, Cm1E3, Cm1F4, Cm1F5, and Cm1H8). A total of 17 alleles were amplified, with variations in the mean number between four to two alleles per locus. The size per locus ranged from 170 to 360 bp. The average inbreeding coefficient was 0.126 (G0), -0.040 (G1), and 0.131 (G2). No null or exclusive alleles were found. The observed heterozygosity values for G1 and G2 demonstrated the preservation of genetic variability (0.453 and 0.409, respectively). In conclusion, the genetic diversity of the parental generation (G0) and the two progenies generations (G1 and G2) were adequate, which demonstrates that the genetic improvement program was conducted correctly; however, it is important to continue to evaluations the genetic diversity of the future progeny.

One of soybean problem in Indonesia is leaf damage caused by the Spodoptera litura. The aim of the study was to identify the resistance of soybean genotypes againts army worm based on the preference index and morphophysiological characters. 150 soybean genotypes were grown under field condition from February to May 2018 in Malang (East Java, Indonesia). The preference test was conducted in the laboratory using G100H as resistant reference plant to armyworm. The result showed that the preference index was ranged from 0.09-1.82. A total of 105 genotypes showed a low preference index (resistant), 39 genotypes showed a high preference index (susceptible), and a genotype has similar preference index with the reference plant (has equal resistance with G100H). Based on the preference index and morphophysiological characters, 150 soybean genotypes can be grouped into eight clusters. A genotype from cluster VIII (Anjasmoro/Rajabasa-41) has characteristics of low leaf water content, dense leaf trichomes, and the preference index of 0.14. Those characteristics could be the attributes of the soybean genotypes that is resistant to S. litura. The Anjasmoro/Rajabasa-41 was recommended to be cultivated in Indonesian, or may be used as a gene source in the breeding program for S. litura resistance

Key message Utilizing a high-density integrated genetic linkage map of hexaploid sweetpotato, we discovered a major dominant QTL for root-knot nematode (RKN) resistance and modeled its effects. This discovery is useful for development of a modern sweetpotato breeding program that utilizes marker-assisted selection and genomic selection approaches for faster genetic gain of RKN resistance. Abstract The root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] (RKN) causes significant storage root quality reduction and yields losses in cultivated sweetpotato [Ipomoea batatas (L.) Lam.]. In this study, resistance to RKN was examined in a mapping population consisting of 244 progenies derived from a cross (TB) between ‘Tanzania,’ a predominant African landrace cultivar with resistance to RKN, and ‘Beauregard,’ an RKN susceptible major cultivar in the USA. We performed quantitative trait loci (QTL) analysis using a random-effect QTL mapping model on the TB genetic map. An RKN bioassay incorporating potted cuttings of each genotype was conducted in the greenhouse and replicated five times over a period of 10 weeks. For each replication, each genotype was inoculated with ca. 20,000 RKN eggs, and root-knot galls were counted ~62 days after inoculation. Resistance to RKN in the progeny was highly skewed toward the resistant parent, exhibiting medium to high levels of resistance. We identified one major QTL on linkage group 7, dominant in nature, which explained 58.3% of the phenotypic variation in RKN counts. This work represents a significant step forward in our understanding of the genetic architecture of RKN resistance and sets the stage for future utilization of genomics-assisted breeding in sweetpotato breeding programs.

The use of chia (Salvia hispanica L.) seeds as functional food is increasing worldwide and research on plant traits is important as the crop spreads. The seedling stage has been identified as crucial for establishment, survival, and competition with weeds but information on chia at this stage is scanty, especially regarding root traits. In this study, 8 genotypes of chia: 4 populations (Australia, Mexico, Peru, Basilicata) and 4 breeding lines (G3, G8, G17, WS) were evaluated under controlled conditions at two early stages (six leaves, S-6; ten leaves, S-10) with the aim to assess growth characteristics and variability in root morphological traits. The shoot height and dry matter were measured together with the following root traits: dry matter and architectural parameters characterized through image analysis of root scans: length, surface, average diameter, tips, forks and crossings. Plants showed a greater phenotypic variation at S-6 than at S-10 (average CV = 40% and 22%, respectively). A high variability was recorded for root biomass, root volume, number of forks and crossings (average CV = 54, 40, 44 and 48%, respectively), while root diameter showed lower variability (average CV = 10%). Four principal components explained more than 97% of the total variance and root length, surface area, volume and average diameter contributed mainly to the variability. Cluster analysis showed that genotypes were very different for morphological root traits. Australia and G8 had the most developed root system with longer and coarser roots. Our results could be used in a breeding program for new cultivars with a more vigorous seedling.

Potential resistance to the guava root-knot nematode, Meloidogyne enterolobii, in 91 selected sweetpotato (Ipomoea batatas [L.] Lam.) genotypes was evaluated in six greenhouse experiments. Ten thousand eggs of M. enterolobii were inoculated on each sweetpotato genotype grown in a 3:1 sand to soil mixture. Sixty days after inoculation, the percentage of total roots with nematode-induced galls was determined, and nematode eggs were extracted from roots. Significant differences (P < 0.001) between sweetpotato genotypes were found in all six tests for gall rating, total eggs, and eggs per gram of root. Resistant sweetpotato genotypes were calculated as final eggs per root system divided by the initial inoculum, where Pf/Pi < 1 (reproduction factor; final egg count divided by initial inoculum of 10,000 eggs), and statistical mean separations were confirmed by Fisher’s least significant difference t test. Our results indicated that 19 out of 91 tested sweetpotato genotypes were resistant to M. enterolobii. Some of the susceptible genotypes included ‘Covington,’ ‘Beauregard,’ ‘NCDM04-001’, and ‘Hernandez.’ Some of the resistant sweetpotato genotypes included ‘Tanzania,’ ‘Murasaki-29,’ ‘Bwanjule,’ ‘Dimbuka-Bukulula,’ ‘Jewel,’ and ‘Centennial.’ Most of the 19 resistant sweetpotato genotypes supported almost no M. enterolobii reproduction, with

Jatropha curcas L. is an oilseed with multiple applications, especially the pharmaceutical-industrial one. Cultivation is still very low due to the lack of commercial varieties, therefore, with the need to start the genetic improvement program and select superior genotypes, it is essential to know the genetic variability of the culture. Thus, the purpose of this study was to evaluate the vegetative growth, grain yield and oil and protein content in seeds populations of Jatropha curcas, to support the species breeding program. The experiment was carried out at the University Federal de Vicosa, State of Minas Gerais, Brazil, using a randomized complete block split-plot design with four replications and 4-plant plots, spaced at 2.5 m. Each plot consisted of clones of six populations coming from the towns of Janauba (J1, J2, J3, J4 and J5) and Bonfim (B1), located in Minas Gerais. The 4.5-year-old populations were evaluated for plant height, stem diameter, leaf and fruit dry matter, grain yield and oil and protein content. The populations presented different plant heights (2.97 m), stem diameters (13.49 cm) and leaf dry matter (0.818 g) amounts. The J5 population showed taller plants (3.29 m) with longer stem diameter (15.34 cm). The greatest dry leaf weight (0.864 g leaf-1) was observed in the J2 population. The populations did not present genetic variability for fruit dry matter, grain yield and oil and protein content. Overall, the J5 population stood out with the highest levels of growth, grain yield and seed oil (31.7%) content.

Bacterial blight (BB), caused by Xanthomonas citri pv. malvacearum (Xcm), is a destructive disease to cotton production in many countries. In the U.S., Xcm race 18 is the most virulent and widespread race and can cause serious yield losses. Planting BB-resistant cotton cultivars is the most effective method of controlling this disease. In this study, 335 U.S. Upland cotton accessions were evaluated for resistance to race 18 using artificial inoculations by scratching cotyledons on an individual plant basis in a greenhouse. The analysis of variance detected significant genotypic variation in disease incidence, and 50 accessions were resistant including 38 lines with no symptoms on either cotyledons or true leaves. Many of the resistant lines were developed in the MAR (multi-adversity resistance) breeding program at Texas A&M University, whereas others were developed before race 18 was first reported in the U.S. in 1973, suggesting a broad base of resistance to race 18. A genome-wide association study (GWAS) based on 26,301 single nucleotide polymorphic (SNP) markers detected 11 quantitative trait loci (QTL) anchored by 79 SNPs, including three QTL on each of the three chromosomes A01, A05 and D02, and one QTL on each of D08 and D10. This study has identified a set of obsolete Upland germplasm with resistance to race 18 and specific chromosomal regions delineated by SNPs for resistance. The results will assist in breeding cotton for BB resistance and facilitate further genomic studies in fine mapping resistance genes to enhance the understanding of the genetic basis of BB resistance in cotton.

Studies on genetic diversity could enhance taxonomic authentication and evolutionary relationship among the species of Ocimum. Therefore, diversity among 36 Ocimum accessions representing species from different regions of world were analyzed using Start Codon-Targeted Polymorphism (SCoT) and inter-simple sequences repeat (ISSR) marker. Marker systems used in this study was potentially targeted the different regions of the genome and included 18 SCoT and 15 ISSR primers, which showed successful amplification profile for Ocimum. Between these two, SCoT revealed the highest mean value of percentage of Polymorphism (84.6%), polymorphic information content (PIC, 0.65), and resolving power (Rp, 8.80), which were higher than ISSR. A total of 140 and 111 amplicons were obtained with SCoT and ISSR marker. The Mantel test indicted a significant correlation (r2 = 0.44) between ISSR and SCoT, which suggested a common genetical background among the accessions. The principal coordinate study showed the selection of different Ocimum genotypes by the cluster analysis. This study will help and support identification, genetic mapping, and molecular ecology to enhance the breeding program's efficiency for developing elite varieties to meet industrial demand globally. The present study is the first report of the genetic diversity, and relationship determination with SCoT-based molecular marker among Ocimum accessions.

Wampee [Clausena lansium (Lour.) Skeels] was originally native to the southern part of China, and had a long history of cultivation. Wampee has been an important species in the development of the fruit breeding program in the genus Clausena, family Rutaceae. In addition to fruit characteristics and bark color, it is difficult to distinguish different varieties of wampee, more difficult of identification of seedling stage. In this study, we determined and analyzed the complete chloroplast genome of Jixin, seedless, and sweet wampee varieties. By comparison, it was found that the sweet wampee is 150 bp less than the other two varieties. We designed a pair of specific primers to distinguish between sweet wampee and other varieties, and it also has better discriminating ability through the analysis of seedlings. The complete chloroplast genome will provide valuable information for the development of highly variable DNA markers for future variety identification and population analysis studies of wampee.

An ambitious vanilla (Vanilla planifolia Jacks. ex Andrews) breeding program was started in Madagascar in the early 1950s to control Fusariosis, a serious crop disease caused by the soil fungus Fusarium oxysporum. The breeding program has produced tens of thousands of new vanilla genotypes of which a small number have been selected and conserved. This article examines the history of the Malagasy breeding work during the second half of the twentieth century, and outlines a possible strategy to exploit the data and exceptional genetic resources it has produced. The National Center for Research Applied to Rural Development has preserved 19 of the very diverse and original hybrids at the vanilla station in Ambohitsara (Antalaha, Madagascar). Two of them are particularly remarkable, namely Manitra ampotony for its exceptionally high vanillin content and Tsy taitra for its strong resistance to Fusariosis and its aromatic profile, which is similar to that of Bourbon vanilla. However, the global vanilla industry remains fragile because varietal diversity now available cannot overcome current and foreseeable constraints. The hybrids formed from multiple crosses between V. planifolia and three aromatic species, (V. pompona Schiede, V. tahitensis J.W. Moore and V. phaeantha Rchb.f.), constitute a preferred resource for further vanilla breeding. Facilitating its wide use by current research and extension teams is, in our opinion, essential to meet the growing need of producers for better-adapted varieties to supply the market of one of the most highly prized natural flavors in the world.