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Twenty-eight hybrids produced from diallel crossing excluding reciprocals among eight parents were studied along with the parents for combining ability for yield and 12 yield components. The study revealed the importance of both additive and non-additive gene effects in governing yield and most of the yield components with preponderance of non-additive gene action for most of the yield components. The analysis of variance for combining ability indicated that mean square due to general combining ability (GCA) was significant for all the characters except for number of tillers/m2, panicle length (cm), number of spikelets /panicle, number of fertile spikelets / panicle, 1000 – grain weight(g) and grain yield(tha-1) which was non significant. Mean square due to specific combining ability (SCA) were significant for all the characters except for spikelets/panicle, fertile spikelets/panicle, 1000-grain weight(g) and grain yield(tha-1) which were non significant. This suggests the importance of both additive and non-additive gene effects in the materials under study. The parent WAB 450-I-B-163-41 was found to be a good general combiner. The hybrids WAB 56-144-FX x WAB 56-100, WAB 450-1-B-163-41 x IRAT 317,WAB 450 -1-B163-41 x IR 47-701-6-3-1, WAB 450-1-B-163-41 x IRAT 239,WAB 35-1-FX x WAB 56 -100, WAB 35 -1-FX x WAB 56-100, IRAT 239 x WAB 56 -100 and IRAT 317 x IRAT 239 have shown significant favorable (SCA) effect for yield and different yield components. Since non- additive/dominance components were higher than the additive components for all the characters in both F1 and F2 generations, bi parental mating and/or reciprocal recurrent selection could be used for genetic improvement of these characters. Keywords: Diallel analysis, combining ability, additive and non additive gene effects, GCA effect, SCA effect.

Food is the most basic of human needs and adequate nutrition is universally recognized as a fundamental human right. However, despite the fact that the world's agricultural resources and the current sensational wave of biotechnological revolution are amply sufficient to assume a reasonable diet to everybody, a very significant proportion of the world's population is still suffering from serious under nutrition. There is the need to correct the assumption that the biotechnological revolution is not the eureka for the world's food problem. The objective of this paper is to challenge and possibly change the notion that biotechnology alone is the magic wand that brings solution to all of agriculture's pitfalls, by clarifying misconceptions concerning these underlying assumptions. The article reviews some of the highlights of modern plant biotechnology and discusses the potential applications and the limitations in the betterment of farming systems in this millennium and beyond. Despite the fact biotechnology will facilitate the farming of crops and rearing of livestock with multiple durable resistance to the vast array of pests and diseases particularly in the absence of pesticides and other non-degradable toxic chemicals, there is also enough evidence to prove that it will not ensure absolute food security, protect the environment and reduce the poverty level in the developing world. International Journal of Agriculture and Rural Development Vol. 7(2) 2006: 26-32

Agricultural development is caught between increased competition accompanied by decreasing prices, land degradation and concerns for sustainability, environment, safe food and animal / human health. Pesticides have been around in some form or another for centuries and have posed a lot of harm to our crops, environment and animals over the years. The increased environmental and public health awareness and the need to implement sustainable agricultural production systems have discouraged the injudicious use of pesticides. Integrated pest management (IPM) and Good agricultural practices (GAP) aims to minimise the use of chemical pesticides and to ensure an integration of various control measures in an informal manner without harmful effects on the environment and occupational and public health. Decision makers in developing countries have to find an appropriate balance between a careful reversal of proactive pesticide support in the traditional agricultural development agenda, which nevertheles does not endanger food security and rural development objectives. For a successful implementation of IPM and GAP, government policy on agricultural development need to provide financial resources for their continual development. International Journal of Agriculture and Rural Development Vol. 7(1) 2006: 80-84

The storage rot of yam ( Dioscorea spp ) starts from the field to the storage barn. Fungi pathogens affecting yam tubers are controlled by either synthetic pesticides or plant extracts.The following plant extracts, Vernonia amygdalina (bittter leaf), Azadirachta indica (neem), Ocimum gratissimum (nchuanwu), Pergularia spp . (utazi), Citrus aurantifolia (lime), Allium sativum (gallic), and Capsicum annum (red pepper) were used to control the rot of yam (caused by Aspergillus niger). The ethanol extracts of the test plants were observed to have higher fungitoxic ability than the water extracts on A. niger , which was isolated from the rotten yam tubers. Ethanol extracts of A. indica and O. gratissimum were observed to have the highest percentage fungi growth inhibition, having 68.8% and 65.2% respectively, while A. sativum, and C. annum had the lowest with 36.3% and 40.6% respectively. A. indica was also observed to have the highest severity and A. sativum had the lowest. However, yam tubers which were treated 2 days before inoculation were observed to have more inhibitory effect on the fungi pathogen than those treated 2 days after inoculation. Keywords : storage-rot, yam-tubers, plant-extracts, fungal-pathogens, severity International Journal of Agriculture and Rural Development Vol. 6 2005: 74-80