SEED QUALITY OF MAIZE INBRED LINES WITH

DIFFERENT OIL AND PROTEIN CONTENTS AND GENETIC BACKGROUND.

Miriam Munamava, Susana Goggi and Linda Pollak

Iowa State University and USDA-ARS

BackgroundBackground Corn breeding program: crossing

and selecting for oil and protein. Stiff Stalk crossed with germplasm

from Argentina. Non- Stiff Stalk crossed with

germplasm from St. Croix. Developed lines of different oil and

protein content.

ObjectivesObjectives To characterize the inbred lines for

seed quality. To evaluate the effect of oil and

protein levels on seed quality. To evaluate the effect of genetic

background and production location on seed quality.

Material and MethodsMaterial and Methods Seed production

Ames-IAClinton-ILColombia-MOHooper-NEStarkville-MS

Table 1 Description of Germplasm used in the Study

Entry Seed composition

Genotype

1 High protein SC01:N1310-378-11-1-1-7-3-B2 High protein SC01:N1310-378-11-1-1-4-4-B3 High protein AR16035:S02-325-1-1-6-4-7-B4 High protein AR16035:S02-325-1-1-6-6-11-B5 High oil SC01:N1310-338-31-6-2-1-6-B6 High oil AR16035:S02-325-1-1-6-6-3-B7 High oil AR16035:S02-325-1-1-6-3-13-B8 Low oil AR16035:S02-325-1-1-6-3-9-B9   B7310   MO17

Standard Germination TestStandard Germination Test

Planting on Paper towels Seedling evaluations

Saturated cold test Seeds planting

Saturated Cold Test

Leakage of electrolytes: amino acids and organic acids.

Poor membrane integrity in deteriorated, low vigor seeds.

Electrical Conductivity TestElectrical Conductivity Test

ee-- ee-- ee-- ee--

ECEC Imbibe seeds in

deionized water for 24 hs at 25o C

Individual Seed Analyzer

Increased temperatureTemperature: 42o C for 96h

High relative humidity

Planting:Over CCP covered with sand

AA TestAA Test

Other TestsOther Tests Soak test Fast green (FG) 100 seed weight Inbred quality index (IQI)

SC+AA+FG+Soak + [ 200- (EC6h+EC24h)]60

IQI =

Results and DiscussionResults and Discussion

Table 2. Levels of significance from ANOVA for ten maize Table 2. Levels of significance from ANOVA for ten maize inbred lines evaluated in four locations.inbred lines evaluated in four locations.

Variable Inbred Inbred*location

Standard germination *** ***

Cold test ** ***

AA ** ***

EC *** ***

Soak test *** ***

Seed weight *** ***

Table 3. Seed vigor tests comparisons between groups of lines bulked Table 3. Seed vigor tests comparisons between groups of lines bulked by exotic genetic background, Argentina (AR) and St. Croix by exotic genetic background, Argentina (AR) and St. Croix (SC), and seed composition, high oil (HO), low oil (LO)(SC), and seed composition, high oil (HO), low oil (LO)..

Contrast Cold AA EC Soak

AR vs. SC ns ns * *

HO vs. LO * ns ns **

B73 vs. AR ns ns ns ns

MO17 vs. SC ns ns * **

Table 4. Means cold test results Locations

IA MO IL NE ....….………………%..…………………. 1 HP 60 37 73 61 2 HP 52 73 84 80 3 HP 69 55 52 80 4 HP 77 53 52 68 5 HO 57 37 65 36 6 HO 88 43 39 77 7 HO 75 51 77 71 8 LO 81 59 60 80 9 B73 71 57 77 59 10 MO17 57 65 40 48 LSD (0.05) 32 22 23 24

Table 5. Means AA test results. Locations

IA MO IL NE ..………………..%....……………… 1 HP 37 51 7 7 51 2 HP 41 75 67 60 3 HP 48 64 93 48 4 HP 65 63 56 88 5 HO 43 41 77 35 6 HO 57 63 63 76 7 HO 43 47 87 84 8 LO 45 59 67 53 9 B73 45 68 53 64 10 MO17 56 81 89 61 LSD (0.05) 32 22 24 26

Table 6 . Means electrical conductivity results (24h).

Locations IA MO IL NE ..…………………… s ..………………… 1 HP 5.0 7.3 4.6 7.1 2 HP 7.0 3.5 4.5 4.9 3 HP 4.5 4.6 3.0 4.3 4 HP 3.6 5.0 6.5 3.4 5 HO 5.3 3.9 2.1 9.5 6 HO 4.5 3.7 4.2 4.1 7 HO 4.8 3.7 4.0 3.7 8 LO 4.5 5.2 4.2 4.8 9 B73 3.9 2.0 2.3 2.4 10 MO17 3.7 2.6 3.0 4.2 LSD (0.05) 1.5 2.1 2.0 2.3

Table 7 . IQI for different locations. Locations IA MO IL NE 1 5.7 4.4 7.1 5.0 2 4.2 7.1 7.2 6.4 3 6.2 5.2 8.0 6.3 4 8.1 5.0 4.5 7.5 5 4.1 5.4 8.9 1.6 6 7.1 6.5 4.8 6.7 7 5.7 5.4 7.9 7.3 8 6.0 4.4 6. 9 6.2 9 7.0 7.9 8.1 8.0 10 6.6 8.4 8.1 6.0 LSD (0.05) 1.5 1.8 2.1 2.6

Table 8. IQI and relative ranking of the inbred lines. IQI Ranking

1 HP 5.4 9

2 HP 6.3 5

3 HP 6.5 3

4 HP 6.3 5

5 HO 5.0 10

6 HO 6.3 5

7 HO 6.6 4

8 LO 5.9 8

9 B73 7.7 1

10 MO17 7.2 2

ConclusionsConclusions Low protein lines have the lowest seed vigor.

When protein levels were high, seed quality was high regardless of oil content.

Mo17 and B73 have the highest IQI. Inbred Quality Index results suggests that seed quality attributes should be considered in a comprehensive breeding program.

Inbred line 4 (high protein) has the highest vigor when produced in IA and NE.

ConclusionsConclusions

Inbred lines with Argentina germplasm have the highest seed quality.

Seeds produced in IL have the best quality, while those produced in MO have the lowest quality.

AcknowledgementsAcknowledgements Tom Hoegemeyer- NE Kevin Montgomery- IL David Willmot - MO Paul Williams- MS Penny Meyerholz Phillip Dixon (ISU Stats)