MARC details
| 000 -LEADER |
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| fixed length control field |
03892nam a22004457a 4500 |
| 001 - CONTROL NUMBER |
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| control field |
G80084 |
| 003 - CONTROL NUMBER IDENTIFIER |
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| control field |
MX-TxCIM |
| 005 - DATE AND TIME OF LATEST TRANSACTION |
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| control field |
20230704201319.0 |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION |
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| fixed length control field |
121211s ||||f| 0 p|p||0|| | |
| 020 ## - INTERNATIONAL STANDARD BOOK NUMBER |
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| International Standard Book Number |
970-648-120-6 |
| 040 ## - CATALOGING SOURCE |
|---|
| Original cataloging agency |
MX-TxCIM |
| 041 ## - LANGUAGE CODE |
|---|
| Language code of text/sound track or separate title |
eng |
| 072 #0 - SUBJECT CATEGORY CODE |
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| Subject category code |
E16 |
| 072 #0 - SUBJECT CATEGORY CODE |
|---|
| Subject category code |
F01 |
| 090 ## - LOCALLY ASSIGNED LC-TYPE CALL NUMBER (OCLC); LOCAL CALL NUMBER (RLIN) |
|---|
| Classification number (OCLC) (R) ; Classification number, CALL (RLIN) (NR) |
CIS-4154 |
| 100 1# - MAIN ENTRY--PERSONAL NAME |
|---|
| 9 (RLIN) |
832 |
| Personal name |
Pixley, K.V. |
| Miscellaneous information |
Genetic Resources Program |
| Field link and sequence number |
INT1617 |
| 245 10 - TITLE STATEMENT |
|---|
| Title |
Open-pollinated maize varieties : |
| Remainder of title |
a backward step or valuable option for farmers? |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) |
|---|
| Place of publication, distribution, etc. |
Nairobi (Kenya) : |
| Name of publisher, distributor, etc. |
CIMMYT, |
| -- |
KARI, |
| Date of publication, distribution, etc. |
2002. |
| 300 ## - PHYSICAL DESCRIPTION |
|---|
| Extent |
8 pages |
| 340 ## - PHYSICAL MEDIUM |
|---|
| Material base and configuration |
Printed |
| 520 ## - SUMMARY, ETC. |
|---|
| Summary, etc. |
Maize farmers require varieties appropriate to their anticipated level of investment in inputs and ,with high probability of producing an acceptable grain yield when challenged by common biotic and abiotic constraints. The objectives of this study were to quantify the relative genetic advantage of hybrids over OPVs under a range of growing conditions typical for farmers in southern and eastern Africa, both when first- or second-generation ("recycled") seed is used, and to investigate scenarios under which hybrids or OPVs are the more profitable option for farmers. In our first experiment, we found that four elite hybrids consistently produced about 18%. more grain yield than 10 improved elite OPVs when grown at 16 sites with mean yield between 1.8 and 7.3 t ha-l. We proceeded to examine the consequences of recycling or saving grain from hybrid or OPV maize crops for use as seed for subsequent crops. Trials at five sites in Zimbabwe compared planting of FI seed and F2 grain of 10 commercial hybrids, FI and F2 of 10 topcross hybrids (using an OPV as male for a single cross), and F2 and F3 of 10 OPVs. Use of the advanced generation grain instead of Fl (F2 in the case of OPVs) seed resulted in 32%. average yield loss for hybrids, 16% yield loss for topcrosses and 5% yield loss for OPVs. We used these results to conduct simple break-even yield analyses to identify scenarios where use of OPV rather than hybrid varieties might be economically advantageous. We concluded that in some farming systems, particularly where yield levels are low (e.g. below 1.5 t ha-l) and hybrid seed and fertilizer prices are high relative to price of grain, highest return to investment may result from use of improved OPV seed, which is cheaper than hybrid seed and can be recycled with little or no yield loss. The improved OPVs are particularly advantageous if the money saved by using OPV instead of hybrid seed is used to purchase additional inputs such as fertilizer, herbicide or hiring additional labor. Although use of OPV instead of hybrid seed is a backward step in terms of expected grain yield, improved OPVs represent an economical option for resource-poor maize farmers in marginal areas or when hybrid seed and fertilizer prices are high relative to price of grain. |
| 536 ## - FUNDING INFORMATION NOTE |
|---|
| Text of note |
Genetic Resources Program|Research and Partnership Program |
| 546 ## - LANGUAGE NOTE |
|---|
| Language note |
Text in English |
| 591 ## - CATALOGING NOTES |
|---|
| Affiliation |
0409|AGRIS 0401|AL-Maize Program |
| 594 ## - STAFFID |
|---|
| StaffID |
INT1888|INT1617 |
| 595 ## - COLLECTION |
|---|
| Collection |
CIMMYT Staff Publications Collection |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Crop yield |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
1066 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Economic analysis |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
1088 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Experimentation |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
4432 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Farmers |
| 9 (RLIN) |
1654 |
| Source of heading or term |
AGROVOC |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Fertilizers |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
1111 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Growth |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
9439 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Maize |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
1173 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Pollination |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
5187 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name as entry element |
Varieties |
| Source of heading or term |
AGROVOC |
| 9 (RLIN) |
1303 |
| 650 17 - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| 9 (RLIN) |
1151 |
| Topical term or geographic name as entry element |
Hybrids |
| Source of heading or term |
AGROVOC |
| 700 1# - ADDED ENTRY--PERSONAL NAME |
|---|
| Personal name |
Banziger, M. |
| Miscellaneous information |
Research & Partnership Program |
| -- |
Excellence in Breeding |
| Field link and sequence number |
INT1888 |
| 9 (RLIN) |
834 |
| 773 ## - HOST ITEM ENTRY |
|---|
| Place, publisher, and date of publication |
Nairobi (Kenya) : CIMMYT, KARI, 2004. |
| Related parts |
p. 22-28 |
| Title |
Integrated Approaches to Higher Maize Productivity in the New Millennium; Proceedings of the Eastern and Southern Africa Regional Maize Conference, 7; Nairobi (Kenya); 5-11 Feb 2002 |
| Record control number |
G79461 |
| International Standard Book Number |
970-648-120-6 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) |
|---|
| Koha item type |
Conference proceedings |
| Source of classification or shelving scheme |
Dewey Decimal Classification |