Effect of Some Agronomic Practices to Increase Maize Yield in Ghana
Low plant densities of maize are often observed in fields of farmers practising no-till agriculture which causes low grain yield in Ghana. With the increasing population and consumption of maize in the country, research must be directed to solve this problem to enhance maize production. In this paper, a 2x3 factorial experiment in randomized complete block design with 4 replications was carried out at Wioso in the Atwima-Nwabiagya District in the Ashanti Region of Ghana during the major season of 2007 in order to come out with the best practices in maize production. The objectives of the study were to determine the right period of refilling maize field and the comparative effect of refilling with seed and seedling on the growth, optimum population density, and yield of maize. The factors were material for refill, which was either seeds or seedlings, and time of refilling either at 5, 10, and 15 days after planting. The results showed that refilling with seedlings produced the greatest positive effect in the number of leaves per plant, leaf length, leaf diameter, plant height and stem girth. Furthermore, refilling with seedlings contributed more to the optimum plant population density. Total grain yield when seedlings were used as refill was 967kg per hectare more than when seeds were used as refill material. On the other hand, plants from seeds refill were weak, lodged more and allowed much solar radiation penetration to the ground. Grain yield from seed refill plants was 6%, whilst seedling refill plants contributed 34% to the total grain yield. Refilling at 5 days after planting induced greater growth than 10 or 15 days after planting. The results indicate that it is possible to do refilling in maize field by using seedling as this contributes more than the traditional method of using seeds.
Introduction to Plant Physiology. Edited by W.G. Hopkins
contributed by a variety of authors in which different strategies for insect control are discussed. All the content is contributed by authors from the USA, with the exception of a chapter on enhancing insect resitance in rice written by authors from the International Rice Research Institute, and a chapter on Bt crystal proteins by Marnix Peferoen, whose competent contribution certainly does not suggest that he was included as a “token European”! The emphasis on American authors (and research) gives this book a rather onesided feel, although many of the individual chapters do take a more wide-ranging view. Inevitably, the volume is a little selective, even as a survey of research in the USA; for example, although the possible role of peroxidases in plant defence against insects is discussed at length, other oxidative enzymes that are equally likely to play a role in defence, such as lipoxygenases and polyphenol oxidases, are not mentioned. The volume is built around three chapters on the use of Bt toxins for insect control, which is entirely appropriate given the widespread use of their encoding genes, with applications in transgenic maize and potatoes described in detail. However, alternatives to the expression of Bt toxins in transgenic plants, such as the introduction of genes encoding foreign protease inhibitors, amylase inhibitors, lectins, cholesterol oxidase, and chitinases are given full coverage, as are some less well-developed areas such as manipulation of secondary metabolism. There are also good chapters on the more applied aspects of using transgenics, such as managing engineered resistance. Inevitably, some chapters are better than others, but the standard is generally good, and no chapter is unworthy of inclusion. The volume as a whole is very well produced, and the quality of the figures is high; however, the index is not wholly accurate, although it is quite thorough. All in all, this is a volume that can be confidently recommended as a sound purchase for libraries, and for individual researchers with interest in the subject area.
Die wisselwerking tussen ekonomiese en konstitusionele hervormings in Suid‐Afrika
Abstract This article deals with the interplay between economic and constitutional reforms in South Africa. Historical and contemporary forces which obtain in these spheres are taken into consideration after which a number of conclusions are drawn.