Correlated responses to recurrent selection for grain yield in maize

Experiments were conducted in three field environments with the following objectives: (1) to evaluate the progress from seven cycles of reciprocal recurrent selection in Iowa Stiff Stalk Synthetic (BSSS(R)] and Iowa Corn Borer Synthetic #1 (BSCBl(R)] and six cycles of half-sib family selection in \u27Alph\u27 (i.e., BS12) maize (Zea mays L.) populations, (2) to compare the response of unimproved and improved maize variety hybrids to different levels of nitrogen fertilizer and plant density, and (3) to evaluate the influence of nitrogen and plant density on the morphological and physiological traits associated with recurrent selection for grain yield in maize. Each experiment was grown in randomized complete blocks with a split-split-plot arrangement and two replications. Nitrogen fertilizer levels (0, 90, 180, and 270 kg N/ha) were main plots, plant densities (39,500; 59,300; 79,000; and 98,800 plants/ha) were subplots, and five variety hybrids, BSSS(R)CO x BSCBl(R)CO, BSSS(R)C5 x BSCB1(R)C5, BSSS(R)C7 x BSCB1(R)C7, BS12CO x B14A, and BS12C6 x B14A, were randomized as sub-subplots. We obtained data on grain yield and grain-yield components, flowering traits, plant traits, leaf area, leaf orientation, lodging, dry-matter productivity, and harvest index

Performance characteristics and egg quality of Commercial Layers Fed Processed Mango Seed Kernel meal at varying inclusion levels

The effect of dietary inclusion of mango seed kernel meal (MSKM) was investigated in commercial layers using 390 twelve weeks growing pullets. The mango seed kernel was cut opened sliced and divided into four equal parts. First part was soaked in cold water for 24 hours then drained and sundried. Second part was soaked in lye for 24 hours drained and sundried while the third part was parboiled for 20 minutes then sundried and the last part was sundried only. These were then used to formulate twelve experimental diets and one control diet. Birds were fed for a period of 8 and 12 weeks during growing and laying phase respectively. Growth performance, egg production and quality parameter were monitored. A significant (P<0.05) difference was recorded in the final weight, weekly weight gain and feed conversion ratio with 15% parboiled having the overall best performance. Egg production performance took a different dimension, birds placed on 10% lye treated MSKM based diet had the best results in feed intake per 30 eggs and cost of feed per tray of egg. Laying birds placed on 20% sundried MSKM based diet was least performed. All parboiled MSKM based diets proved to be better than the control. Haugh unit and yolk index were influenced significantly (P<0.05) by the utilization of differently processed MSKM. Birds fed 15% lye and 15% cold water treated MSKM based diet produced egg with best and least haugh unit respectively

Methyl orange, an organic dye: its health impact and sorptive removal from waste water

AbstractMethyl Orange (MO) a member of Azo dyes are commonly used as synthetic dyes in textile, food, paper and cosmetics. Their use is easy and cost-effective, compared with natural dyes. However, azo bonds are hardly removed because of their high water solubility as well as low exhaustion with the potential for persistence and accumulation in the environment, therefore aqueous solution of MO is toxic and irritating. Thus, the removal of them from industrial wastewaters is capital with regard to protect public health, environment, and aquatic life

Genetic analysis of grain yield and resistance of extra-early-maturing maize inbreds to northern corn leaf blight

Open Access Article; Published online: 11 Feb 2021Maize (Zea mays L.) is a food security crop in sub-Saharan Africa (SSA). Incidence of northern corn leaf blight (NCLB), caused by Exserohilum turcicum, in lowlands of SSA during the past decade has caused 30–70% reduction in maize yield. This study (a) examined the combining abilities of extra-early maize (EEM) inbreds and classified them into heterotic groups; (b) elucidated gene action controlling resistance to NCLB; (c) assessed grain yield (GYLD) and yield stability of EEM hybrids underNCLB infection; and (d) identified testers. One hundred and fiftyEEMhybrids, obtained by crossing 15 inbreds each of white- and yellow-endosperm maize using the North Carolina Design II, plus six checks, were evaluated in nine environments, six of which were inoculated with an isolate of E. turcicum and three of which were non-inoculated in 2018 and 2019. The white and yellow inbreds were placed in three heterotic groups using the heterotic grouping based on general combining ability (GCA) of multiple traits and stability of GYLD using the genotype plus genotype × environment (GGE) biplot analysis. The GCA, specific combining ability (SCA) and genotype × environment (G×E) interactions were significant for GYLD, disease severity, and other measured traits. The GCA effects were more important than the SCA effects for GYLD and NCLB severity scores across environments, implying that recurrent selection could facilitate improvement for GYLD and NCLB resistance. Three inbred testers and four single-cross testers were identified for developing high-yielding NCLB-resistant hybrids. Four white and five yellow single-cross hybrids were identified for on-farm testing and possible commercialization

Genetic variances and relationship among traits of an early maturing maize population under drought-stress and low nitrogen environments

Article purchasedDrought and low soil nitrogen (low N) are major causes of low grain yield of maize (Zea mays L.) in sub-Saharan Africa (SSA). An early maturing maize population, TZE-Y Pop DT STR, had undergone four cycles of selection for drought tolerance, followed by four selection cycles for resistance to Striga hermonthica (Del.) Benth., which is normally conducted under low N (about 30 kg N ha-1). The objectives of this study were to estimate residual genetic variances, predict future gains from selection, and investigate inter-trait relationships in the population under drought-stress, low N and across research environments. North Carolina Design I was used to develop 250 full-sib progenies from the improved population, which were evaluated in three drought-stress and two low N environments in Nigeria, 2011 to 2013. Additive genetic variances were not significant for most traits under the research conditions. The predicted gains from selection for grain yield were 5.3, 8.5 and 7.5% cycle-1 under drought, low N, and across environments. These results suggested the absence of substantial genetic variability in the population to ensure progress from selection. Ears per plant (EPP), ear aspect (EASP), plant aspect (PASP), and stay green characteristic (STGR) were consistently identified as important secondary traits under both research conditions. We concluded that there is need to introgress new sources of favorable alleles for drought-stress and low N tolerance into the population for guaranteed progress from selection, using EPP, EASP, PASP, and STGR in combination with yield in a selection index under drought-stress and low N

Integrated dataset of screening hits against multiple neglected disease pathogens.

New chemical entities are desperately needed that overcome the limitations of existing drugs for neglected diseases. Screening a diverse library of 10,000 drug-like compounds against 7 neglected disease pathogens resulted in an integrated dataset of 744 hits. We discuss the prioritization of these hits for each pathogen and the strong correlation observed between compounds active against more than two pathogens and mammalian cell toxicity. Our work suggests that the efficiency of early drug discovery for neglected diseases can be enhanced through a collaborative, multi-pathogen approach

Assessment of three substrata for maize seed testing

Three substrata: topsoil, sand and sawdust, each with sterilised and unsterilised treatments were assessed as potential media for maize seed testing. Seeds of Oba Supa 1, a tropical white maize hybrid, were used. One hundred seeds were planted in plastic containers per replicate, each substratum was replicated three times and data were collected on fifty seedlings per replication per substratum. Traits assessed were germination percentage, emergence index, number of primary roots, and root and shoot lengths. The experiment was repeated four times. Substratum had highly significant effect on number of primary roots and root and shoot lengths but not on germination percentage and emergence index. Sterilisation significantly favoured shoot length but not other traits. Sand, sterilised or unsterilised, gave more uniform and reproducible test results than sawdust and topsoil. These results support the conclusion that any of the substrata may be used for the purpose of assessing the germinability of a seedlot. Seed testing involving seedling evaluation or measurements of seedling root and shoot lengths should, however, be done with sterilised sand. Key Words: Seed, sterilisation, substrata, Zea mays Résumé Trois milieux: la terre de surface, le sable et la siure de bois, chacun avec un traitement stérilisé et no stérilisé ont été évalués come des milieux potentiels pour tester les graines. Les graines d' Oba Supa 1, un hybride de maïs blanc tropical populaire ont été utilisées. Cent graines ont été plantées dans des contenants plastiques par répétition, chaque substratum a été répété trois fois et les données ont été collectées sur cinquante graines dans chaque répétition pour chaque substratum. Les caractères évalués étaient le pourcentage de germination, l'indexe d'émergence, le nombre de racines primaires, et la longeur de racines et des feuilles. L'experience a été répétée quatre fois. Le substratum a eu un effect sugnificatif sur le nombre de racines primaires, et la longeur des raciness et des feuilles mais non sur le pourcentage de germination et l'indexe d'émergence. La sterilisation a favorisé très significativement la longeur de feuilles et non pas les autres caractères. Le sable, stérilisé ou non stérilisé, a donné des résults de teste plus uniformes et reproductibles plus que la siure et la terre de surface. Ces résults ont confirmé la conclusion que n'importe quel milieu de substrat peut être utilisé avec objectif d'evaluer le pouvoir germinatif des graines. Le testage des graines comprenant l'evaluation des jeunes plantules ou le mesurement des racines des jeunes plantules et la longeur des feuilles devra, cependant, être fait avec du sable stérilisé. Mots Clés: Pouvoir germinatif des graines, sterilisation, substrata, Zea mais (African Crop Science Journal 8(4) 2000: 441-445