School of Agriculture and Biotechnology
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Item The Critical Onion Growth Stages For Selective Protection From Thrips Tabaci Lindeman (Thysanoptera:Thripidae) Infestation(Kenya Agricultural Research Institute, Nairobi (Kenya), 2006-01) Waiganjo, M. M.; Sithanantham, S.; Mueke, J. M.; Gitonga, L. M.Field trials were conducted during 2000-2001 at KARIandrsquo;s Mwea-Tebere and Kiboko farms to establish the effect of onion thrips, Thrips tabaci Lindeman on onion bulb yields and to identify the critical onion growth stage for selective protection from the pest infestation. Yield reductions of 59 and 27% were recorded in the first and second crops respectively at Mwea-Tebere, but no significant yield reductions were observed in a third crop grown at Kiboko with low thrips infestation. A significant onion yield response to thrips infestation was observed during the 2nd month after transplanting (bulb-formation) and 3rd month after transplanting (bulb-enlargement), but no significant response was observed during the 1st month (pre-bulbing) and 4th month (maturation stage). Onion protection during bulb-formation and enlargement stages only, resulted in higher marginal returns than full season pesticide application. The studies suggest that control recommendations for onion could be refined to optimize need-based protection.Item Keys to Soil Taxonomy(United States Department of Agriculture: Natural Resources Conservation Service, 2006) United States Department of AgricultureThe publication of this edition of Keys to Soil Taxonomy (the 10th edition) coincides with the 18th World Congress of Soil Science, to be held at Philadelphia, Pennsylvania, in July 2006. The last time the World Congress was hosted in the United States was in 1960 at Madison, Wisconsin. At that time, Soil Classification: A Comprehensive System, 7th Approximation was released for review and testing. The classification system was officially adopted for use in the United States soil survey program in 1965. The first edition of Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys was published in 1975. Over the years Soil Taxonomy has been modified and expanded to reflect our increased knowledge of the world’s soils. After the first eight editions of the Keys to Soil Taxonomy were released, the second edition of Soil Taxonomy was published in 1998. Since then, the 9th edition of the keys was published in 2003, and now this 10th edition in 2006. The publication Keys to Soil Taxonomy serves two purposes. It provides the taxonomic keys necessary for the classification of soils in a form that can be used easily in the field. It also acquaints users of the taxonomic system with recent changes in the system. This edition of the Keys to Soil Taxonomy incorporates all changes approved since publication of the ninth edition in 2003. We plan to continue issuing updated editions of the Keys to Soil Taxonomy as changes warrant new editions. The authors of the Keys to Soil Taxonomy are identified as the “Soil Survey Staff.” This term is meant to include all of the soil classifiers in the National Cooperative Soil Survey program and in the international community who have made significant contributions to the improvement of the taxonomic system.Item World reference base for soil resources 2014 International soil classification system for naming soils and creating legends for soil maps(Food and Agriculture Organization, 2014) FAO; IUSS Working Group WRBThe first edition of the World Reference Base for Soil Resources (WRB) was released at the 16th World Congress of Soil Science at Montpellier in 1998. At the same event, it was also endorsed and adopted as the system for soil correlation and international communication of the International Union of Soil Sciences (IUSS). The second edition of the WRB was released at the 18th World Congress at Philadelphia in 2006. After an additional eight years of intensive worldwide testing and data collection, the third edition of the WRB is presented. This publication builds on and reflects the valuable work of the authors of the earlier drafts and editions of the WRB, as well as the experiences and contributions of many soil scientists who participated in the work of the IUSS Working Group on the WRB. The WRB is a soil classification system for naming soils and creating soil map legends. It is hoped that this publication will contribute to the understanding of soil science in the general public and in the scientific community. The publication has been made possible by the sustained efforts of a large group of expert authors, as well as the cooperation and logistic support of the IUSS and the Food and Agriculture Organization of the United Nations (FAO).Collection Collection Collection