Evaluation of M6 Ofada Rice Mutant Selections and Parents for Grain Physico-Chemical and Nutritional Characters

Rice consumers are becoming more conscious of the varieties they consume in terms of nutritional quality. Selection for quality improvement would benefit from induced variability as innate sources are becoming exhausted. This study was carried out to assess the extent of improvement of rice grain quality yield for the benefit of the farmers and the consumers. Two Ofada rice varieties (FUNAABOR 1 and FUNAABOR 2) were irradiated with 60Co gamma rays to elicit variation towards selection for grain improvement in 2013. Individual seed selections from different treatment levels in M1 and subsequent generations were harvested and replanted for advancement to M6 generation. Harvested seeds from selected promising M6 mutants and parents were subjected to physical, chemical and nutritional analysis.  Analysis of Variance (ANOVA) was applied to data to generate character overall mean and variance estimates from which heritability estimates were computed. Means of the different mutants were compared with parents using Duncan Multiple Range Test (DMRT). Ofada rice mutants and parents varied significantly for all the studied grain traits. The mutants and parents had long grains (6.6mm - 7.1mm). Mutant, OG13602 _100 had high values for amylose content (20.01%), followed by OG13608_300 (19.47%). The two mutants (OG13602_100 and OG13608_300) respectively also recorded the highest values for crude protein (6.41% and 6.28%), fat (3.94% and 3.81%), fibre (2.14% and 2.05%), and ash content (3.92% and 3.71%). Overall, the entries clustered into two groups along the parental lines and present opportunities for hybridization. High heritability with concomitant high genetic advance was recorded for amylose, ash and moisture content. All selected promising Ofada rice mutants and parents had long grains. Specifically, mutants OG13602_100 and OG13608_300 which expressed superior amylose, protein, fat, fibre and ash contents present opportunities for further improvement for grain quality. The significant variability of the studied traits revealed additional gains from further selection

Assessment of 60Co gamma radiation on early phenological stages of two generations of OFADA rice

Traditional Ofada rice varieties from South-West, Nigeria is preferred for its unique taste, aroma and massive potential for export but has low yield. Based on this background, two Ofada rice varieties, FUNAABOR 1 and FUNAABOR 2 were irradiated to create genetic variability as it affects vegetative traits. Seeds from the varieties were exposed to nine levels of 60Co gamma irradiation (0, 50, 100, 150, 200, 250, 300, 350 and 400 Gy). The seeds were nursed for 30 days before M1 seedlings were transplanted into a well tilled soil in a two factorial RCBD with three replicates. Selections from M1 plants were used to establish M2 plants generation. The results revealed diverse effects of 60Co gamma irradiation treatments on different plant vegetative traits. The establishment rates of M1 Ofada rice population were unaffected (p > 0.01) by increasing gamma irradiation from 0 to 300 Gy but decreased at 350 Gy. Above 300 Gy, tiller numbers, plant height, lodging incidence, leaf number, leaf length and leaf angle decreased significantly when compared with control (p < 0.01) in both generations (M1 and M2). Moderately tillered (10 tillers), tall plant (116.9 cm) obtained from 350 dosage rate recorded highest grain weight of 7.8 g per panicle. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) promoted by the irradiation dosages in M1 selection indicate the extent of environmental influence. High broad sense heritability observed from leaf number, leaf angle, leaf length, leaf blade colour, basal leaf sheath colour and grain weight per panicle shows possibility of rapid genetic improvement of these characters through selection

Analysis of grain yield components of selected upland rice grown in valley bottom soil under rates of foliar ortho-silicate acid fertiliser

Attainment of potential yield (PY) of upland rice grown in valley bottom (VB) soil is limited by inadequate supply of beneficial nutrients. Previous study revealed that VB soil increase grain weight plant-1 (GWP) in upland rice by 70%, which is still far below its PY. Application of ortho-silicate acid (OSA) fertiliser, as silicon source at optimum rate, could help to boost the yield of upland rice. Five upland rice cultivars, comprising of three medium maturing (NERICA 1,4,7) and late maturing (MOROBEREKAN and OFADA), were grown in pots filled with VB soil. Four rates of foliarly applied OSA fertiliser (0, 250, 500, and 750 ml ha-1) were imposed across stages of growth of rice cultivars. OSA fertiliser increased GWP significantly (P<0.01) with application of 500 ml ha-1 having the best effect. At 250 ml ha-1, 1000 grain weights was more associated with number of branches panicle-1 and number of grains branch-1 panicle-1; while at 500 ml ha-1, GWP was closely associated with % number of fertile spikelets panicle-1 plant-1 (%NFSPP), total weight of panicle plant-1 (TWPP) and length of panicle plant-1 (LPP). Total number of spikelets plant-1 was more associated with total number of panicle plant-1 at 750 ml ha-1. The highest significant (P<0.01) GWP was observed in MOROBEREKAN (9.27 g plant-1); while the lowest was in Ofada (4.79 g plant-1). Application of 500 ml ha-1 of the fertiliser is recommended for these rice cultivars. Further improvement in yield of upland rice grown on VB soil under foliarly applied silicon should focus on % NFSPP, TWPP, and LPP.L\u2019atteinte d\u2019un rendement potentiel (RP) de riz pluvial cultiv\ue9 dans le sol de fond de vall\ue9e (FV) est limit\ue9e par un apport insuffisant de nutriments b\ue9n\ue9fiques. Une \ue9tude pr\ue9c\ue9dente a r\ue9v\ue9l\ue9 que le sol de fond de vall\ue9e (VB) augmente le poids de grain par plante (PGP) dans le riz pluvial de 70%, ce qui est encore bien en dessous de son rendement potentiel (RP). L\u2019application d\u2019engrais d\u2019acide orthosilicate (AOS), comme source de silicium \ue0 un taux optimal, pourrait aider \ue0 augmenter le rendement du riz pluvial. Cinq cultivars de riz pluvial, comprenant trois \ue0 maturation moyenne (NERICA 1,4,7) et \ue0 maturation tardive (MOROBEREKAN et OFADA), ont \ue9t\ue9 cultiv\ue9s dans des pots remplis de terre FV. Quatre taux d\u2019engrais AOS appliqu\ue9s par voie foliaire (0, 250, 500 et 750 ml ha-1) ont \ue9t\ue9 impos\ue9s \ue0 tous les stades de croissance des cultivars de riz. L\u2019engrais AOS a augment\ue9 PGP de mani\ue8re significative (P <0,01) avec l\u2019application de 500 ml ha-1 ayant le meilleur effet. \uc0 250 ml ha-1, 1000 poids de grain \ue9taient davantage associ\ue9s au nombre de branches par panicule et au nombre de grains par branche et par panicule; alors qu\u2019\ue0 500 ml ha-1, PGP \ue9tait \ue9troitement associ\ue9 au% nombre d\u2019\ue9pillets fertiles par panicule et par plante (% NEFPP), au poids total de la panicule par plante (PTPP) et \ue0 la longueur de la panicule par plante (LPP). PGP significatif le plus \ue9lev\ue9 (P <0,01) a \ue9t\ue9 observ\ue9 \ue0 MOROBEREKAN (9,27 g plante-1); tandis que le plus bas \ue9tait \ue0 Ofada (4,79 g de plante-1). L\u2019application de 500 ml ha-1 d\u2019engrais est recommand\ue9e pour ces cultivars de riz. Une am\ue9lioration suppl\ue9mentaire du rendement du riz pluvial cultiv\ue9 sur le sol FV sous silicium appliqu\ue9 par voie foliaire devrait se concentrer sur le% NEFPP, PTPP et LPP

Evaluation of improved cassava genotypes for yield and related traits for a better breeding strategy under different agroecologies in Nigeria

Open Access Article; Published online: 29 Mar 2021This study aimed at determining shoot and root characteristics of cassava as affected by root yield and the influence of soil moisture on vegetative growth and yield. Thirty cassava genotypes were evaluated for morphological and physiological characterization in three locations in Nigeria: Ibadan, Mokwa and Zaria. Randomized complete block design was used with four replicates. Studies on the pasting properties of the genotypes were also carried out. Data were collected on plant height, stem girth, stay-green ability, garri and fresh root weight. Genotypes differed significantly (P < 0.05) across and within locations for shoot and root characteristics. Across locations, genotype 011663 had the highest plant height (132.4 cm); 30572 had the largest stem girth (8.6 cm); and 010040 was the best stay-green (2.2). Genotype 011086 had the highest number of roots per plot (95.7), 950289 had the highest fresh root yield (24.3 t/ha), and 990554 had the highest percentage of dry matter (35.2). Trends in root yields across locations were Ibadan (28.9 t/ha), Mokwa (20.3 t/ha), and Zaria (8 t/ha). Five genotypes IITA-TMS-IBA950289, 010034, 990554, 011807, and 980581 had negligible interactions with the environment and so have broad adaptation and are considered stable; and two clones 011807 and 950166 were found to be the best for pasting properties. Breeding strategies that consider root size, total root number, harvest index, dry matter, with applications for household foods and industrial uses, will be an effective and efficient way to select genotypes for high yield

Correlations of Vegetative and Reproductive Characters with Root Traits of Upland Rice under Imposed Soil Moisture Stress

An understanding of the relationship between traits related to plant performance is advantageous in rice breeding for tolerance to drought and increase in grain yield. Correlations studies involving root, vegetative and reproductive traits were carried out with sixteen rice genotypes under differing soil moisture through a combination of three amounts of moisture and two periods of application. Data from root,  vegetative and grain yield traits were used to compute phenotypic and genotypic coefficients of variation (CV), correlations and heritability. Phenotypic and genotypic CV were generally low, with the exception of root branching and grain weight per plant. Heritability estimates were also low. Among the root traits, the highest  heritability value of 36.6 and 30.5 was recorded by root thickness and root  branching respectively while the estimate for 100-grain weight (48.7), days to  flowering (47.8) and primary branching (45.9) were moderate. Genetic advance was highest for root thickness, root branching and grain weight per plant. Root volume showed significant negative correlation with root thickness at phenotypic and  genotypic levels (-0.124, -0.286), but had positive correlation with fresh root  weight (0.340, 0.917) and dry root weight (0.338, 0.910). Root volume and root  thickness exhibited counteracting relationships with primary branching, secondary branching, spikelets number per panicle and spikelet fertility. Root branching was significantly correlated with grain weight per plant at genotypic level. The diffused relationships of root traits with the vegetative and reproductive traits underscore their intricate nature and require consideration in trait selection for direct and indirect increase in grain production.Keywords: Root volume, root thickness, root dry weight, drought, grain yield

Genotype × environment analysis of cowpea grain production in the forest and derived savannah cultivation ecologies

Differential performance of genotypes in different cultivation environments has remained a challenge to farmers and plant breeders, the emphasis being the selection of high yielding and stable genotypes, across similar ecologies. A set of nine cowpea genotypes were&nbsp; cultivated in Ago-Iwoye and Ayetoro, two locations representing high and moderate moisture zones. Plantings were done with the early and late season rains in Ago-Iwoye and mid-late season rains of Ayetoro. Statistical analysis was done to understand genotype reaction to the different environments and the plant and environment factors mediating the performance. The Additive Main Effect and Multiplicative Interaction (AMMI) model captured 61.30% of the total sum of squares (TSS). The main effects: genotype (G) environment (E) and their interaction (GxE) were significant with the largest contribution of 28.70% by the environment while the interaction and genotype fractionscaptured 20.20% and 12.40%, respectively. The percentage contribution of the main effects and GxE to total sum of squares (TSS) for traits was not consistent. The Genotype plus Genotype-by-Environment (GGE) analysis summarized 91.30% of the variation in genotype performance across environment. The cultivation environments were separated into two, with IT 95M 118 as the vertex genotype in the Ayetoro while TVU 8905 was the topmost genotype in Ago-Iwoye. The two genotypes recorded the highest grain weight per plant (GWPP) but were also the most unstable The stable genotypes IT 95M 120 and IT 86 D 716 flowered relatively late compared to others, are taller, had higher vegetative score and are low grain producers. Key words: AMMI, drought, GGE, stability, Vigna unguiculat

Effect of tadalafil in chronic renal failure rabbits: relevance to erectile dysfunction

It is of great importance to investigate an effective and reliable medication against chronic renal failure (CRF)-related erectile dysfunction (ED), which aims to improve patients’ life qualities. The concentrations of cyclic guanosine monophosphate (cGMP) in the corpus cavernosal smooth muscle of both CRF and control rabbits were measured. The effects of various concentrations of tadalafil, papaverine, and sodium nitroprusside on the relaxation responses of corpus cavernosal smooth muscle pre-contracted with phenylephrine in CRF rabbits were observed. There was significant difference in the concentration of cGMP between CRF and control rabbits (P<0.01). Tadalafil had the greatest impacts on CRF rabbits when given the same concentration of papaverine or sodium nitroprusside and particularly significant differences were identified under the concentration levels of 10−5 and 10−4 mol/L (P<0.01). The results suggest that the cGMP concentrations of the corpus cavernosum had been greatly reduced in CRF rabbits compared with control rabbits and that tadalafil may be an ideal medication for use in the treatment of CRF-related ED