Agro-Morphological, Physico-Chemical and Molecular Characterization of Rice Germplasm with Similar Names of Bangladesh

Thirty-one duplicate and similar named rice germplasms of Bangladesh were studied to assess the genetic variation for the agro-morphological and physico-chemical traits and simple sequence repeat banding patterns during 2009–2012 at Bangladesh Rice Research Institute. The range of variations within the cultivar groups showed higher degree. The principal component analysis showed that the first five components with vector values > 1 contributed 82.90% of the total variations. The cluster analysis grouped the genotypes into four clusters, where no duplicate germplasm was found. The highest number(11) of genotypes was constellated in cluster I and the lowest(3) in cluster II. The intra- and inter-cluster distances were the maximum in cluster I(0.93) and between clusters I and IV(24.61), respectively, and the minimum in cluster IV(0.62) and between clusters I and III(5.07), respectively. The cluster mean revealed that the crosses between the genotypes of cluster I with those of clusters II and IV would exhibit high heterosis for maximum good characters. A total of 350 alleles varied from 3(RM277) to 14(RM21) with an average of 7.8 per locus were detected at 45 microsatellite loci across the 31 rice accessions. The gene diversity ranged from 0.48 to 0.90 with an average of 0.77, and the polymorphism information content values from 0.44(RM133) to 0.89(RM206) with an average of 0.74. RM206, RM21, RM55, RM258 and RM433 were considered as the best markers on the basis of their higher polymorphism information content values. The dendrogram from unweighted pair-group method with arithmetic average clustering also classified the genotypes into four groups, where group IV comprised of 20 genotypes and group III of one genotype, but no duplicate was found. Finally, similar and duplicate named rice germplasms need to be conserved in gene bank as are distinct from each other.

Screening of Sapindus germplasm resources in China based on agro-morphological traits

Sapindus L.species are widely cultivated for biodiesel,biomedical,and biochemical raw materials in southern China.However,yields fuctuate widely due to the lack of high-yielding,high-quality,stable cultivars.Therefore,the objectives of this study were to evaluate three species and one variety among 149 nationwide Sapindus species and screen for elite accessions which would serve as Sapindus breeding materials.Accessions were evaluated on 19 agro-morphological traits by correlation analysis and principal component analysis.These displayed substantial diversity and a broad range of economic traits.In particular,accessions of Sapindus mukorossi and Sapindus rarak had more variation in economic traits than Sapindus delavayi and Sapindus rarak var.velutinus.Increased saponin accumulation may be achieved at the cost of seed oil production.Thirty elite accessions for oil and saponin production,and for comprehensive utilization were screened and accessions no.80,110,and 112 had significant potential to produce high yields.These elite accessions will facilitate the identification of genetic determinants of valuable traits and the effective utilization of trait variability in Sapindus breeding.

Agro-Morphological Variability in Eight Bambara Groundnut (Vigna subterranea (L.) Verdc.) Morphotypes from Zinder (Niger)

Bambara groundnut (Vigna subterranea (L.) Verdc.) has economic importance for the producers and the traders as cash crop since it generates substantial income for households in Niger. The objective of this study was to assess eight (8) Bambara groundnut morphotype from Université André Salifou de Zinder in Niger Republic by their morphological and agronomic characters. The experiment was conducted in a randomized complete block design with three replications during the rainy season of 2020-2021. Data were collected on the Number of leaves, Plant height (cm), Growth habit (cm), Terminal leaflet length, Terminal leaflet width, Number of nodes/stem, Number of stems/plant, Number of pods/plant, Weight of 100 pods (g), Weight of 100 seeds (g), Length of seeds (mm), Width of seeds (mm), Weight of seeds/Plot (kg). There were significant differences for all characters, except Number of leaves, Terminal leaflet length, Terminal leaflet width, Length of seeds (mm) Weight of 100 pods (g), Weight of 100 seeds (g). The morphotypes UZ-VZ-04, UZ-VZ-03, UZ-VZ-06, UZ-VZ-02 and UZ-VZ-05 have demonstrated good performance for grain weight per plot and can be useful for a breeding program.

Identification of Quantitative Trait Loci for Rice Quality in a Population of Chromosome Segment Substitution Lines

The demand for high quality rice represents a major issue in rice production. The primary components of rice grain quality include appearance, eating, cooking, physico-chemical, milling and nutritional qualities. Most of these traits are complex and controlled by quantitative trait loci （QTLs）, so the genetic characterization of these traits is more difficult than that of traits controlled by a single gene. The detection and genetic identification of QTLs can provide insights into the genetic mechanisms underlying quality traits. Chromosome segment substitution lines （CSSLs） are effectivetools used in mapping QTLs. In this study, we constructed 154 CSSLs from backcross progeny （BC3F2） derived from a cross between ＇Koshihikari＇ （an Oryza sativa L. ssp. japonica variety） as the recurrent parent and ＇Nona Bokra＇ （an O. sativa L. ssp. indica variety） as the donor parent. In this process, we carried out marker-assisted selection by using 102 cleaved amplified polymorphic sequence and simple sequence repeat markers covering most of the rice genome. Finally, this set of CSSLs was used to identify QTLs for rice quality traits. Ten QTLs for rice appearance quality traits were detected and eight QTLs concerned physico-chemical traits. These results supply the foundation for further genetic studies and breeding for the improvement of grain quality.