Variability and traits association in maize (Zea mays L.) for yield and yield associated characters

Maize (Zea mays L.) is world’s third most important cereal crop that has a remarkable productive potential in Bangladesh. In Bangladesh, maize is the second most important cereal crop in terms of production. The selection for high yield with desirable traits depends on the genetic variability in the existing germplasm. Successful breeding programs need adequate genetic variation for selection and improvement based on necessity. The research was conducted in the experimental farm of the Department of Genetics and Plant Breeding, Bangladesh Agricultural University, Mymensingh during November 2015 to April 2016. The aim of this study was to evaluate the performance of 20 maize genotypes based on their yield and yield contributing characters to determine existing genetic variability. The extrapolated ANOVA for different yield contributing parameters showed a high degree of variation among the genotypes used. Correlation co-efficient analysis revealed that yield plant−1 (g) had positive and significant association with ear girth (cm), 1000-kernel weight (g), yield plot−1 (g), grain yield (tha−1) with dry weight. The genotypes differed significantly for most of the phenotypic traits. The phenotypic co-efficient of variation (PCV) was higher than genotypic co-efficient of variation (GCV) in all traits studied indicating that those traits were interacted with the environment. The traits under study expressed wide heritability estimates (26.81% to 99.95%). Among the characters, highest heritability was recorded for 1000-kernel weight (g). High heritability along with high genetic advance was noticed for 1000-kernel weight (g), yield plot−1 (g)and grain yield (tha−1). Considering different desirable traits P-12, Popcorn, V90-1, 988 were observed as superior genotypes. The data would be useful for proper identification and selection of appropriate parents in breeding programs to develop new maize varieties

Allelopathic Effects of Water Hyacinth [Eichhornia crassipes]

Eichhornia crassipes (Mart) Solms is an invasive weed known to out-compete native plants and negatively affect microbes including phytoplankton. The spread and population density of E. crassipes will be favored by global warming. The aim here was to identify compounds that underlie the effects on microbes. The entire plant of E. crassipes was collected from El Zomor canal, River Nile (Egypt), washed clean, then air dried. Plant tissue was extracted three times with methanol and fractionated by thin layer chromatography (TLC). The crude methanolic extract and five fractions from TLC (A–E) were tested for antimicrobial (bacteria and fungal) and anti-algal activities (green microalgae and cyanobacteria) using paper disc diffusion bioassay. The crude extract as well as all five TLC fractions exhibited antibacterial activities against both the Gram positive bacteria; Bacillus subtilis and Streptococcus faecalis; and the Gram negative bacteria; Escherichia coli and Staphylococcus aureus. Growth of Aspergillus flavus and Aspergillus niger were not inhibited by either E. crassipes crude extract nor its five fractions. In contrast, Candida albicans (yeast) was inhibited by all. Some antialgal activity of the crude extract and its fractions was manifest against the green microalgae; Chlorella vulgaris and Dictyochloropsis splendida as well as the cyanobacteria; Spirulina platensis and Nostoc piscinale. High antialgal activity was only recorded against Chlorella vulgaris. Identifications of the active antimicrobial and antialgal compounds of the crude extract as well as the five TLC fractions were carried out using gas chromatography combined with mass spectroscopy. The analyses showed the presence of an alkaloid (fraction A) and four phthalate derivatives (Fractions B–E) that exhibited the antimicrobial and antialgal activities