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Applying the concept of ideotypes in a breeding strategy presupposes that the breeder already knows what traits to select. This study was conducted to determine the substantive indicators of erect plant architecture in dry bean (Phaseolus vulgaris L.). In the first of two field studies, data on 17 architectural traits were collected at two locations on parental plants and progenies originating from five distinct cycles of a phenotypic recurrent selection program. In the second study, similar data were collected at one location on 480 F3 lines from six crosses. A stepwise multiple regression procedure was used to determine traits that are effective indicators of erect plant architecture. Hypocotyl diameter, plant height, branch angle, and pods on the main stem and especially in the midsection were selected for inclusion in the regression model, suggesting their important contributory role in a dry bean ideotype. Dry bean breeders should emphasize these four traits for effective selection and efficiency in a breeding program for erect plant architectures.

Electrotransformation also known as electroporation is the most reliable and efficient tool for plasmid DNA uptake. Electrotransformation efficiency is function of many factors which include (1) number of cell washes prior to electroporation, (2) electroporation cell number, (3) electroporation DNA amount, and (4) cell growth phase. Those factors have limitedly been concomitantly investigated in E. coli DH10B strain. This study is aimed to explore above key factors to define the optimal conditions for high electrotransformation efficiency. The results showed that electrotransformation efficiency of E. coli DH10B was enhanced to 1.5 x 10 9 cfu/µg by washing cells three times with 15 ml of 10% glycerol. This washed off extra salts from cell suspension and enhanced electrotransformation by preventing arcing and enhancing cell resistance while ensuring minimal level of conductivity. Early exponential phase at 0.15 OD600 was the best growth phase for enhancing electrotransformation of E. coli DH10B. The results also showed that higher electrotransformation efficiency was similarly achieved when 0.5 x 10 10 and 0.6 x 10 10 cell numbers were electroporated with DNA amount ranging from 10 to 40 pg. This study confirmed the optimal conditions for electro competent cell preparation and plasmid DNA electrotransformation, which can result highest transformation efficiency.

Injury to sugarbeet, Beta vulgaris L., from sulfonylurea herbicide residues from preceding cropping years has kindled interest in developing resistant cultivars. This study was conducted to obtain chlorsulfuron (2‐chloro‐N‐[[(4‐methoxy‐6‐methyl‐1,3,5‐triazin‐2‐yl)amino]carbonyl]benzenesulfonamide) resistance from cell cultures and to determine its inheritance and magnitude. Utilizing annual diploid sugarbeet clone REL‐1, dispersed suspension cultures were initiated from callus induced on leaf disk cultured on a modified Murashige and Skoog (MS) agar medium + 1.0 mg L−1 N6‐benzyladenine (BA) and placed in the liquid form of the same medium. Unmutagenized cell clusters were plated on solid medium containing 2.8 nM chlorsulfuron in MS + 1.0 mg L−1 BA. A single colony arose, from which shoots were regenerated. Shoots were resistant to 28 nM chlorsulfuron, a concentration that killed similar shoots of REL‐1. Resistance (designated Sur) was inherited as a monogenic dominant. In vitro shoot resistance to chlorsulfuron was 300 to 1000‐fold greater than in REL‐1. Resistance was also expressed in leaf disk expansion in vitro with MS + 1.0 mg L−1 BA.

Within Enugu and Anambra States, Nigeria, identification of fishes has been based on morphological traits and do not account for existing biodiversity. For DNA barcoding, assessment of biodiversity, conservation and fishery management, 44 fish sampled from Enugu and Anambra States were isolated, amplified and sequenced with mitochondrial cytochrome oxidase subunit I (COI). Twenty groups clustering at 100% bootstrap value including monophyletic ones were identified. The phylogenetic diversity (PD) ranged from 0.0397 (Synodontis obesus) to 0.2147 (Parachanna obscura). The highest percentage of genetic distance based on Kimura 2-parameter was 37.00 ± 0.0400. Intergeneric distances ranged from 15.8000 to 37.0000%. Congeneric distances were 6.9000 ± 0.0140–28.1000 ± 0.0380, with Synodontis as the existing synonymous genus. Confamilial distances in percentage were 16.0000 ± 0.0140 and 25.7000 ± 0.0300. Forty-two haplotypes and haplotype diversity of 0.9990 ± 0.0003 were detected. Nucleotide diversity was 0.7372, while Fu and Li’s D* test statistic was 2.1743 (P < 0.02). Tajima’s D was 0.2424 (P > 0.10) and nucleotide frequencies were C (17.70%), T (29.40%), A (24.82%), G (18.04%) and A + T (54.22%). Transitional mutations were more than transversions. Twenty species (99–100%) were identified with the e-value, maximum coverage and bit-score of 1e−43, 99–100 and 185–1194, respectively. Seventeen genera and 12 families were found and Clariidae (n = 14) was the most dominant among other families. The fish species resolution, diversity assessment and phylogenetic relationships were successfully obtained with the COI marker. Clariidae had the highest number of genera and families. Phylogenetic diversity analysis identified Parachanna obscura as the most evolutionarily divergent one. This study will contribute to fishery management, and conservation of freshwater fishes in Enugu and Anambra States, Nigeria.

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