Phosphorus Level Affects Brown Blotch Disease, Development and Yield of Cowpea
Application of Phosphorus in adequate concentrations could directly or indirectly reduce disease incidence and severity of cowpea brown blotch and improve the forage and grain yield. A field experiment was conducted to investigate the effects of level of phosphorus application on Brown Blotch disease of cowpea (Vigna unguiculata (L.) Walp), caused by Colletotrichum capsici during 2003, 2004 and 2005 planting seasons. Application of phosphorus was at 30, 60, 90 and 120 kg ha of P O. As P level increased numbers of petioles, 1 25 pods, nodules, seed/pod, leaf area and yield significantly increased. Disease incidence and severity of Brown Blotch were significantly reduced at 90 and 120 kg ha of P O was not affected irrespective of the method of 1 25 application. Application method did not affect yield. Reduction in brown blotch disease at higher levels of P was recorded.
Influence of Sokoto Phosphate Rock on Some Soil Properties and the Growth and Yield of Cowpea [Vigna Unguiculata (L)Walp.] Varieties in Sudan Savanna of Nigeria
Phosphate rock has been used over the years as source of P fertilizer especial in acid soils. Sokoto state is rich in PR deposit and could be used to complement the conventional P fertilizer whose use by peasant farmers have been limited by high cost and scarcity. Sequel to this, an Experiment was conducted in 2009 at the Botanical Garden, Department of Biological Sciences, Usmanu Danfodiyo University, Sokoto to determine the influence of Sokoto Phosphate Rock (SPR) on some chemical properties of soil, growth and yield of cowpea [ Vigna Unguiculata (L)Walp.]. The treatments consisted of factorial combinations of two varieties (Dan Gusau (v 1 ) and IT90K-82-2 (v 2 ) and three levels of SPR at 0.062, 0.125 and 0.187g/5kg (25, 50, 75 kg ha -1 ) as well as a control (without fertilizer). The experiment was laid out in a completely randomized design (CRD) replicated three times. SPR applied enhanced availability of nutrients in soil and the general performance of cowpea varieties which increased with increased rate of application. The results of the study indicated a significant difference (p<0.05) in soil available phosphorus, plant tissue phosphorus, soil total nitrogen and plant tissue nitrogen due to application of SPR. Significant difference was also observed in plant height at 2, 4, 6, and 8 weeks after planting (WAP). Similarly, the response of cowpea varieties, dry matter yield at harvest (8WAP) due to application of SPR was significant (p<0.05). Significant interaction effect between variety and applied SPR on plant height, number of branches and dry matter yield were also observed. The results of this investigation revealed that, increased rate of application of SPR progressively increased the growth and yield performance of cowpea and soil available phosphorus. However, absolute values were not high perhaps because of the weekly acidic nature of the soil which does not encourage fast solubilization of P from SPR. Therefore, application of SPR at a rate of 75kg ha -1 could improve cowpea production and therefore recommended. Keywords: Sokoto phosphate rock; Soil parameters; Sudan savanna; Cowpea yield
Genetics of the phenotypic evolution in sheep: a molecular look at diversity-driving genes
Background After domestication, the evolution of phenotypically-varied sheep breeds has generated rich biodiversity. This wide phenotypic variation arises as a result of hidden genomic changes that range from a single nucleotide to several thousands of nucleotides. Thus, it is of interest and significance to reveal and understand the genomic changes underlying the phenotypic variation of sheep breeds in order to drive selection towards economically important traits. Review Various traits contribute to the emergence of variation in sheep phenotypic characteristics, including coat color, horns, tail, wool, ears, udder, vertebrae, among others. The genes that determine most of these phenotypic traits have been investigated, which has generated knowledge regarding the genetic determinism of several agriculturally-relevant traits in sheep. In this review, we discuss the genomic knowledge that has emerged in the past few decades regarding the phenotypic traits in sheep, and our ultimate aim is to encourage its practical application in sheep breeding. In addition, in order to expand the current understanding of the sheep genome, we shed light on research gaps that require further investigation. Conclusions Although significant research efforts have been conducted in the past few decades, several aspects of the sheep genome remain unexplored. For the full utilization of the current knowledge of the sheep genome, a wide practical application is still required in order to boost sheep productive performance and contribute to the generation of improved sheep breeds. The accumulated knowledge on the sheep genome will help advance and strengthen sheep breeding programs to face future challenges in the sector, such as climate change, global human population growth, and the increasing demand for products of animal origin.