The evolution of hybrid maize breeding in Zimbabwe: (Record no. 9493)

000 -LEADER
fixed length control field 03645nam a22003857a 4500
001 - CONTROL NUMBER
control field 64967
003 - CONTROL NUMBER IDENTIFIER
control field MX-TxCIM
005 - DATE AND TIME OF LATEST TRANSACTION
control field 20170719154847.0
008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION
fixed length control field 121211s ||||f| 0 p|p||0|| |
020 ## - INTERNATIONAL STANDARD BOOK NUMBER
International Standard Book Number 92-9146-025-7
040 ## - CATALOGING SOURCE
Original cataloging agency MX-TxCIM
072 #0 - SUBJECT CATEGORY CODE
Subject category code F30
082 04 - DEWEY DECIMAL CLASSIFICATION NUMBER
Classification number 633.15
Item number EAS No. 5
110 2# - MAIN ENTRY--CORPORATE NAME
Corporate name or jurisdiction name as entry element Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), Mexico DF (Mexico)
100 1# - MAIN ENTRY--PERSONAL NAME
9 (RLIN) 955
Personal name Machida, L.
Miscellaneous information Global Maize Program
Field link and sequence number INT3439
Affiliation Maize Productivity Gains through Research and Technology Dissemination. Proceedings of the Eastern and Southern Africa Regional Maize Conference, 5; Arusha (Tanzania); 3-7 Jun 1996
245 00 - TITLE STATEMENT
Title The evolution of hybrid maize breeding in Zimbabwe:
Remainder of title Ingredient for the revolution in maize yields
260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT)
Place of publication, distribution, etc. Addis Ababa (Ethiopia)
Name of publisher, distributor, etc. CIMMYT :
Date of publication, distribution, etc. 1997
340 ## - PHYSICAL MEDIUM
Material base and configuration Printed
520 ## - SUMMARY, ETC.
Summary, etc. The development and release of varietal products from the government maize breeding programme of Zimbabwe evolved through stages when emphasis was on open pollinated varieties (from 1904 to 1932), double cross hybrids (from 1932 to l975), single cross hybrids (from 1960 to the present), three way hybrids (from 1969 to the present) and modified single cross hybrids (from 1977 to the present). For the period under study (1913/14 to 1994/95) the graph of annual average yield levels of maize in the commercial farming sector against year rose from just below one tonne per hectare during the open pollinated varieties era to above five tonnes per hectare during the hybrid varieties era. This occurred simultaneously with the increase in hybrid adoption percentage. When the graph of hybrid adoption percentage against year was about to attain 100% no further increases in yield were observed. This remained so even after hybrid adoption percentage was 100%. Two distinct contributions from the maize breeding programme were influential to the rise in annual average maize yield levels in the commercial farming sector. These are: i) the development and release of double cross hybrids and ii) the development and release of the single cross hybrid, SR52. All the hybrids released after SR52 consolidated the yield gains from hybrid SR52. They filled in 'niches' which could not be served by SR52. In the smallholder farming (communal) sector the results are not as striking as in the commercial farming sector but smallholder farmers benefited from hybrid maize technology especially since 1980. Communal farming sector yield levels were around 0.7 tonnes per hectare before 1981 but from 1981 the graph of annual average yield levels averaged at least one tonne per hectare in all the seasons with good rainfall. The increase in yield from around 0.7 tonnes per hectare to about one tonne per hectare occurred simultaneously with the increase in the graph of deliveries of hybrid maize seed to the communal farming sector. Contributions towards yield improvement from other disciplines like agronomy, soil productivity, extension, seed industry, biometry and plant protection are acknowledged as well since those from breeding are difficult to separate from the rest.
536 ## - FUNDING INFORMATION NOTE
Text of note Global Maize Program
546 ## - LANGUAGE NOTE
Language note English
591 ## - CATALOGING NOTES
Affiliation 9712|AGRIS 9702
594 ## - STAFFID
StaffID INT3439
595 ## - COLLECTION
Collection CIMMYT Publications Collection
650 10 - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name as entry element Crossbreeding
650 10 - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name as entry element Varieties
9 (RLIN) 1303
650 10 - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name as entry element Zimbabwe
653 0# - INDEX TERM--UNCONTROLLED
Uncontrolled term CIMMYT
650 10 - SUBJECT ADDED ENTRY--TOPICAL TERM
9 (RLIN) 1314
Topical term or geographic name as entry element Zea mays
Miscellaneous information AGROVOC
650 10 - SUBJECT ADDED ENTRY--TOPICAL TERM
9 (RLIN) 1151
Topical term or geographic name as entry element Hybrids
Miscellaneous information AGROVOC
650 10 - SUBJECT ADDED ENTRY--TOPICAL TERM
9 (RLIN) 1203
Topical term or geographic name as entry element Plant breeding
Miscellaneous information AGROVOC
700 1# - ADDED ENTRY--PERSONAL NAME
Personal name Ransom, J.K.|Palmer, A.F.E.|Zambezi, B.T.|Mduruma, Z.O.|Waddington, S.R.|Pixley, K.V.|Jewell, D.C.
Relator term eds.
942 ## - ADDED ENTRY ELEMENTS (KOHA)
Koha item type Conference proceedings
Holdings
Withdrawn status Lost status Damaged status Not for loan Collection code Permanent Location Current Location Date acquired Full call number Barcode Date last seen Copy number Price effective from Koha item type
  Not Lost     CIMMYT Publications Collection CIMMYT Knowledge Center: John Woolston Library CIMMYT Knowledge Center: John Woolston Library 2015-02-10 633.15 EAS No. 5 I624172 2015-02-10 1 2015-02-10 Conference proceedings
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Lunes –Viernes 9:00 am. 17:00 pm. Si tiene cualquier pregunta, contáctenos a CIMMYT-Knowledge-Center@cgiar.org