Environmental impact and genetic expressions of new drought tolerant maize genotypes in derived savannah agro-ecology (2021-01-19)
Reduced water resources in sub-Saharan Africa will not only pose threat to the livelihood of poor resource farmers, but also food security in the region. Drought tolerant (DT) maize varieties hold promise to reducing poor resourced farmers’ vulnerability and improve food security in sub-Saharan Africa. Ten maize genotypes obtained from the International Institute of Tropical Agriculture (IITA), were evaluated in 2015 and 2016 using a randomized complete block design experiment with three replications to estimate their genetic variability and predict their genetic advances in the derived savannah agro-ecology. Growth, phenological and yield data were collected from 10 middle row plants. Genetic advance, genotypic, phenotypic and environmental coefficients of variations and their variances were estimated. Principal component and hierarchical cluster analyses were also performed. The dendrogram showed that at 80% dissimilarity point, the genotypes were grouped into clusters A, B and C in both years. The first two principal components explained 91.8% and 93.3% of the total variation in 2015 and 2016, respectively. Number of grains cob-1, plant height and number of days to physiological maturity were consistent in explaining the variations observed in the maize population. Heritability estimates in broad sense ranged from 1.35% for number of leaves to 87.43% for grain yield per hectare. The genetic parameters studied showed significant variations among the growth, phenological and yield data collected that warrants selection and maize improvement program using the DT maize inbred lines in derived savannah agro-ecology.
Phytochemistry and pharmacological activities of Saponaria officinalis L.: A review (2021-01-19)
Saponaria officinalis is an important medicinal plant cultivated in different parts of the globe for its beautiful flowers. Species is commonly known as soapwort. Central Europe is considered as native place for the species and has been introduced in Northern Asia, West Asia, Northern Europe and America. Plant of the species are perennial, stem erect, branched, leaves ovate or ovate-lanceolate, inflorescence dense cymes, calyx green or reddish, often cleft, petals pink to white, fruit capsules, seeds tuberculate-reniform and numerous per fruit. Indigenous people of different parts of the world use this species to cure various ailments. Traditionally roots of the species have been used as urine remover. It is also used for cough, bronchitis, stomach disorders, bone deformations, rheumatism, pimples, skin diseases, bile disorders, liver problems and respiratory system diseases. The leaves were rubbed on the skin as a repellent and also used as sanitizer, diuretic and in liver diseases. Saporins are ribosome inhibitory proteins and play important role for anticancer properties. Different types of saponins are synthesized by the species exhibit anticancer, antimicrobial, insecticidal and antioxidant properties. The present review is focused on the traditional medicinal uses of species along with phytochemical and pharmacological studies. This review will provide a ground for future research of the species.
Seasonal arbuscular mycorrhiza colonization dynamic displays genotype-specific pattern in Iris sibirica L. (2021-01-19)
Arbuscular mycorrhiza (AM) is a widespread symbiotic association between plants and Glomeromycota fungi, that brings nutritional-derived benefits for phytobiont. Influence of plant breeding on arbuscular mycorrhiza susceptibility is a topic of current interest that can have many practical implications. Insights into whether new cultivars have a lower mycorrhizal potential, are critical for optimization of AM use. Aim of this research was to conduct a comparative assessment of AM colonization across a phenophase gradient in two Iris sibirica genotypes: one displaying the wild traits versus a modern reblooming cultivar with double flowers. Analysis showed that both Iris sibirica genotypes developed Paris-morphotype. Results indicated that on average the genotype with simple flowers had a higher AM colonization frequency (84.44±2.15) compared to the new cultivar with double flowers (52.22±6.09). Significant influence was exercised both by genotype (p<0.001) as well as by phenophase (p=0.0013), over colonization frequency. The genotypes displayed contrasting colonization dynamics: highest AM frequency level occurred in spring for the genotype with simple flowers, and in autumn for the one with double flowers. Results suggest that host metabolic state has regulating role over functionality of established AM-symbiotic association according to plant nutritional requirements, while fungi might also respond to increased or decreased carbon flux in the plant, associated with geophyte phenology.
Explants selection for in vitro propagation of Pachyrhizus erosus L. (2021-01-21)
Pachyrhizus erosus tuber is rich in protein asides its agronomical value as a legume, but the seeds by which it is propagated have very low viability. This study established sterilization protocol and effect of various concentrations of auxins and cytokinins on callus production and shoot regeneration from explants of P. erosus. Explants and seeds were sterilized using sodiumhypochlorite (NaClO) solution (5, 10 and 15% v/v) for 5 and 10 mins. Nodal, stem and leaf explants from in vitro germinated P. erosus and tuber from field grown plant were sterilized and cultured on Murashige and Skoog (MS) medium (control) and MS combined with different concentrations of auxins (NAA and 2, 4-D) and cytokinin (BA and Kinetin) and the cultured explants were monitored in terms of degree of callus formation, morphology and colour of callus and also for shoot induction. The results showed that seeds of P. erosus sterilized with 10% NaClO solution for 10 mins and germinated in vitro is the best way of getting sterile nodal, stem and leaf explants for the in vitro propagation of the plant, while tuber explants could be sterilized with 15% NaClO for 10 minutes. Nodal explants inoculated in MS medium supplemented with 1.0 mg/L BA gave the highest shoot regeneration response, while stem explants inoculated on MS medium supplemented with 1.0 mg/L BA and 0.5 mg/L NAA also gave the highest amount of friable callus. The study concluded that in vitro germinated seeds were the best way of getting explant for P. erosus.
In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. The article is to be paginated when the complete issue will be ready for publishing (Volume 13, Issue 1, 2021). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue.