University of Hawaii at Manoa
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Seed Stocks

Field Corn Inbreds
Three types of field corn inbreds are available from HFS:

  1. Inbreds released by HFS.   Forty tropically adapted inbreds (Hi25 to Hi68) have been bred at U. Hawaii and released to growers (Crop Science 37:631-632, 1997; Crop Science 47:459-461, 2007). They enter many experimental and commercial hybrids for silage and grain (Link: fieldcornflyer.doc). HFS also maintains many introduced or locally-bred, tropically adapted inbreds, most of them converted to resistance to Maize Mosaic Virus.
    Click here to view a list of inbreds. Link:  maizeinbreds.xls
  2. Near-Isogenic Lines (NILs).   Tropical flint inbred Hi27 has been converted to >140 near-isogenic lines (NILs) over the past 40 years. This involves many significant “classical” mutants of maize. Many have been discussed in publications of Maize Genetics Newsletter (e.g., Vols. 42, 46, 69, 81).
    • A summary of the mutant genes is found in Link:   nils.doc
    • The NILs are individually described with their origin, map location, conversion history, and details of their appearance and performance in   Link:  nilsdescsription.doc
    • NILs that are now held also by Maize Genetics Coop (as of 2007)  Link: nilsatMGC.xls
    • Photos of most of these NILs are available in     Link:  nilsphotos
  3. Recombinant Inbred Lines (RILs).   HFSF maintains about 1200 inbreds created at U. Hawaii as recombinants from a series of 11 singlecrosses (Moon et al., Maydica 44:301-311, 1999). Parentage is largely tropical x temperate, with parents chosen as differentiating resistance to diseases and insect pests. Link: rils.doc

Field Corn Synthetics and Composites

  1. Synthetics bred by UH.   Six synthetics (HIS1 to HIS6) were developed and released based on inbreds of high general resistance to specific diseases (J. Plant Registration, 2009). Two new synthetics (HIS7 and HIS8) are based on brown-midrib genes.   Link:  fieldsyns&comps.doc
  2. Composites bred by UH.   Three broad-based composites (HIC1 to HIC3) include an  opaque-2 (quality-protein maize) composite, one based on 25% Zea diploperennis and one bred as an “Indian corn” from highly adapted tropical varieties, inbreds and races (J. Plant Registration 3:10-13, 2009).   Link:  fieldsyns&comps.doc

Supersweet Corn Hybrids and Varieties
Seeds marketed by HFS include:

  1. Hawaiian Supersweet #9   (Open-pollinated Variety, Yellow)
  2. Hawaiian Supersweet #9 Silver’ (Open-pollinated Variety, White)
  3. Hawaiian Supersweet #10’   (3-Way hybrid, Yellow)  
  4. Sweet Sarah   (Modified Single-cross hybrid, Yellow)

Many additional hybrids are in advanced tests, including white and bicolor versions of those listed above.  Seeds are also available from CTAHR Agricultural Diagnostic and Seed Services. Link:  Supersweetflyer.doc

Supersweet Synthetics And Composites
HFS has developed and released 17 sub-tropical populations of food corns based on the sweet corn gene su or the supersweet genes bt, bt2 and sh2 (HortScience 33:1262-4, 1998). These are available for use by seedsmen and breeders, and are in permanent storage by USDA. Many are also available through CIMMYT, the international maize and wheat center in Mexico.
Link:  Sweetsyns&comps.doc

Maize Breeding and Genetic Stocks
Several hundred breeding lines and populations exist in the supersweet or silage improvement programs, with additional lines of waxy (“sticky”) and popcorns. Most Hawaiian stocks carry resistance to maize mosaic virus, gene Mv (3L-78), and are selected for tolerance of rust (P. sorghi), blight (E. turcicum), fusarium, earworms, and tropical stresses. Many are daylength sensitive.  Cytosterile breeding stocks with C cytoplasm are available of selected lines for use in hybrid seed production or for use as “sugar corn”. A “Hawaiian Popcorn” hybrid is also available.

Accessions Of The Genus Leucaena
About 1100 accessions of the genus Leucaena have been collected worldwide, grown and characterized at Waimanalo Research Station. Most of the 22 species in this genus are represented. Many accessions have been seed increased and are stored by HFS. Many have been hybridized, to create over 70 hybrids. Several seedless triploid hybrids are available from HFS as clonal progeny. Hybrid population “KX2-Hawaii” with psyllid and cold tolerance and low seediness has been released in 2008 (J. Plant Registration 2:1-4). All significant genotypes have been shared with University of Queensland, Brisbane, Australia, where leucaena has become of major commercial significance as forage crop. Links:  Leucaena&Koa.doc     Leucaenaflyer.doc

Accessions Of Acacia Koa
HFS maintains about 600 accessions of koa, Hawaii’s premier forest tree (Acacia koa Gray). All are growing at the Hamakua Research Station on the Island of Hawaii. An improved composite “Hi Koa Comp 1” has been bred and is in cycle 3 of selection at the Mealani Research Station. It derives from half-sib progenies that were outstanding for form and tolerance of koa wilt (Fusarium oxysporum).  
Link: Leucaena&Koa.doc