Molecular characterization of sweet potato(Ipomoea batatas[L.]Lam)germplasms for desirable traits by using simple sequence repeats markers

Every breeding program that aims to create new and improved cultivars with desired traits mostly relies on information related to genetic diversity.Therefore,molecular characterization of germplasms is important to obtain target cultivars with desirable traits.Sweet potato[Ipomoea batatas(L.)Lam]is widely considered the world’s most important crop,with great diversity in morphological and phenotypic traits.The genetic diversity of 20 sweet potato germplasms originating from Bangladesh,CIP,Philippines,Taiwan,and Malaysia were compared,which was accomplished by genetic diversity analysis by exploring 20 microsatellite DNA markers for germplasm characterization and utilization.This information was effective in differentiating or clustering the sweet potato genotypes.A total of 64 alleles were generated using the 20 primers throughout the 20 germplasm samples,with locus IBS97 having the highest number of alleles(5),whereas locus IbU33 had the fewest alleles(2).The alleles varied in size from 105(IbU31)to 213 base pairs(IBS34).The Polymorphism Information Content(PIC)values for the loci IbL46 and IBS97 varied from 0.445 to 0.730.IBS97 has the highest number of effective alleles(3.704),compared to an average of 2.520.The average Shannon’s diversity index(H)was 1.003,ranging from 0.673 in IbU3 to 1.432 in IBS97.The value of gene flow(Nm)varied between 0.000 and 0.005,with an average of 0.003,whereas genetic differentiation(FST-values)ranged between 0.901 and 1.000.The sweet potato germplasm included in this study had a broad genetic base.SP1 vs.SP9 and SP12 vs.SP18 germplasm pairings had the greatest genetic distance(GD=0.965),while SP1 vs.SP2 germplasm couples had the least genetic diversity(GD=0.093).Twenty genotypes were classified into two groups in the UPGMA dendrogram,with 16 genotypes classified as group“A”and the remaining four genotypes,SP10,SP18,SP19,and SP20,classified as group“B.”According to cluster analysis,the anticipated heterozygosity(gene diversity)of Nei(1973)was 0.591 on average.In summary,SSR markers successfully evaluated the genetic relationships among the sweet potato accessions used and generated a high level of polymorphism.The results of the present study will be useful for the management of germplasm,improvement of the current breeding strategies,and the release of new cultivars as varieties.

Screening and evaluation of chilli(Capsicum annuum L.)genotypes for waterlogging tolerance at seedling stage

Waterlogging is an illustrious abiotic stress and the constrictions it enforces on plant roots have negative effects on growth and development.This study was undertaken to investigate waterlogging stress tolerant potential in chilli(Capsicum annum L.)genotypes through evaluating morphological,physiological,biochemical and anatomical parameters.Thirty-five days old seedlings of 10 chilli genotypes were exposed to waterlogging stress maintaining water height 3–5 cm over the soil surface artificially for three days.This duration(36–38 DAE)was termed as waterlogging period,and subsequent withdrawal of waterlogging condition(39–45 DAE)was regarded as a recovery phase.Based on their survival performance,two tolerant genotypes viz.,SRC-517 and BARI morich-2 and two susceptible genotypes viz.,AHM-206 and RI-1(6)were selected for studying stress tolerance mechanism.Under waterlogging,however,both genotypes(tolerant and susceptible)exhibited reduced root shoot length,dry weight ratio,petiole weight and leaf area,and noticeable reduction regarding these parameters was observed in susceptible genotypes.Moreover,tolerant genotypes displayed a higher recovery than susceptible genotypes after removal of waterlogging stress.Lower reduction of leaf area and photosynthetic pigments as well as higher reduction of relative water content(RWC)were noticed in susceptible genotypes.Higher accumulation of proline and total antioxidant capacity(TAC)during waterlogging condition in tolerant genotypes suggested lower oxidative damage.Although both genotypes lost total soluble sugar(TSS)relative to control at waterlogging stress,better performance was recorded in tolerant genotypes.During the period after the removal of extra water,a similar genotypic response in terms of TSS gain was seen.Undoubtedly,under flooding conditions,the development of aerenchyma cells in tolerant genotypes is a means of tolerance mechanism for long-term survival.Thus,the morpho-physiological and biochemical changes help to understand the tolerance mechanism in chilli under waterlogging stress.

Screening and Assessment of Selected Chilli (Capsicum annuum L.) Genotypes for Drought Tolerance at Seedling Stage

This study was undertaken to investigate oxidative stress tolerant mechanisms in chilli(Capsicum annuum L.)under drought genotypes through evaluating morphological,physiological,biochemical and stomatal parameters.Twenty genotypes were evaluated for their genetic potential to drought stress tolerant at seedling stage.Thirty days old seedlings were exposed to drought stress induced by stop watering for the following 10 days and rewatering for the following one week as recovery.Based on their survival performance,two tolerant genotypes viz.BD-10906 and BD-109012 and two susceptible genotypes viz.BD-10902 and RT-20 were selected for studying the oxidative stress tolerance mechanism.Drought reduced root and shoot length,dry weight,ratio,petiole weight and leaf area in both tolerant and susceptible genotypes,and a higher reduction was observed in susceptible genotypes.Lower reduction of leaf area and photosynthetic pigments were also found in tolerant genotypes.Moreover,tolerant genotypes showed higher recovery than susceptible genotypes after the removal of stress.A higher reduction of relative water content(RWC)may cause an imbalance between absorbed and transpirated water in susceptible genotypes.Higher accumulation of proline in tolerant genotypes might be helpful to for better osmotic maintenance than that in susceptible genotypes.Tolerant genotypes showed higher antioxidant activity as they showed DPPH radical scavenging percentage than the susceptible genotypes.Moreover,closer stomata in tolerant genotypes than susceptible ones helped to avoid dehydration in tolerant genotypes.Thus,the above morphological,physiological,biochemical and stomatal parameters helped to show better tolerance in chilli under drought stress.

In Vitro Regeneration of Endangered Medicinal Hypoxis Species

The genus Hypoxis contains some of southern Africa’s most important wild medicinal species, a situation that has placed most of them amongst endangered species facing extinction. In this study, four Hypoxis species collected from Swaziland: H. argentea, H. filiformis, H. acuminata and H. hemerocallidea, were included to assess their potential for in vitro propagation in order to efficiently conserve these species in the future. Among all types of explants tested only corm explants and seeds gave rise to shoots under the in vitro conditions. For the corm establishment, H. filiformis was the most in vitro responsive species, which had 100% shoot regeneration with high shoot number when cultured on the MS medium supplemented with 3 mg·l-1 kinetin with a piece of shoot attached, while the highest mean shoot number (17) was obtained on the same medium, but with no shoot attachment to the corm explants. H. argentea was the next most responsive species in vitro with up to 70% establishment, while the other two species had only up to 20% of in vitro establishment. For the seed explants, up to 29% seed germination was obtained for H. argentea when the seed coats were crushed before the in vitro culture. The regenerated shoots were rooted in vitro and acclimatized in the greenhouse

Selection of High Yielding and Farmers’ Preferred Genotypes of Bambara Nut (<i>Vigna subterranea</i>(L.) Verdc) in Malawi

Bambara nut (Vigna subterranea (L.) Verdc) is a nutritious legume, however, its production is characterised by use of landraces, which have been maintained by farmers. Lack of improved varieties has contributed to low yields. This re- search was done to identify potentially high yielding and farmers’ preferred genotypes for improved production of Bambara in Malawi. A completely Randomised Block Design experiment with eight genotypes (181CR, 181RD, 194, 137CR, 137RD, 317, 2762 and 2768) and four replicates was implemented at Chitedze, Chitala and Mbawa Research Sta- tions to identify high yielding genotypes. In addition to the yield, farmers’ criteria based on plant vigour, ability to fully bury its pods in the ground (mounding), yield at harvest, maturity period, seed colour, grain size, taste of boiled dry grain and taste of fresh pods were used to identify farmers’ preferred genotypes. Significant yield differences were identified between genotypes (P < 0.0001), sites (P < 0.001) and interaction between genotypes and sites (environment) (P < 0.001). Yield means across sites show that genotype 181CR yielded highly (1322 kg/ha) followed by 2768 (1066 kg/ha), 181RD (1064 kg/ha) and 2762 (841 kg/ha). In contrast to the high yielding genotypes, genotype 137RD gave the lowest yield (485 kg/ha) followed by 194 (573 kg/ha), 317 (617 kg/ha) and 137CR (620 kg/ha). Mbawa Research Sta- tion showed significantly high yields with site mean of 1177 kg/ha compared with Chitedze and Chitala with site means of 703 kg/ha and 530 kg/ha respectively. Farmers ranked the eight accessions in order of importance as follows: 181RD, 181CR, 2768, 137CR, 194, 137RD, 2762 and 317. Combination of yield and farmers’ preference identified three geno- types (181RD, 181CR and 2768) as potential varieties for production in Malawi. Accessions 181RD and 2768 were specifically selected for relish unlike 181CR, which has been selected for use as snack. However, further research on nutrition, value addition and marketing needs to be conducted on the identified genotypes.

FungalTraits:a user-friendly traits database of fungi and fungus-like stramenopiles

The cryptic lifestyle of most fungi necessitates molecular identification of the guild in environmental studies.Over the past decades,rapid development and affordability of molecular tools have tremendously improved insights of the fungal diversity in all ecosystems and habitats.Yet,in spite of the progress of molecular methods,knowledge about functional properties of the fungal taxa is vague and interpretation of environmental studies in an ecologically meaningful manner remains challenging.In order to facilitate functional assignments and ecological interpretation of environmental studies we introduce a user friendly traits and character database FungalTraits operating at genus and species hypothesis levels.Combining the information from previous efforts such as FUNGuild and FunFun together with involvement of expert knowledge,we reannotated 10,210 and 151 fungal and Stramenopila genera,respectively.This resulted in a stand-alone spreadsheet dataset covering 17 lifestyle related traits of fungal and Stramenopila genera,designed for rapid functional assignments of environmental stud-ies.In order to assign the trait states to fungal species hypotheses,the scientific community of experts manually categorised and assigned available trait information to 697,413 fungal ITS sequences.On the basis of those sequences we were able to summarise trait and host information into 92,623 fungal species hypotheses at 1%dissimilarity threshold.

Correction to:FungalTraits:a user friendly traits database of fungi and fungus-like stramenopiles

Correction to:Fungal Diversity(2020)105:116 https://doi.org/10.1007/s13225-020-00466-2 There were errors in the name of author LászlóG.Nagy and in affiliation no.31 in the original publication.The original article has been corrected.