Maize Genetics Cooperation Newsletter vol 84 2010
Please Note: Notes submitted to the Maize Genetics
Cooperation Newsletter may be cited only with consent of authors.
MNLCORCUERA20101.DOC
CASTELAR, ARGENTINA
INSTITUTO DE GEN�TICA DR. E. A. FAVRET, CICVyA INTA
CASTELAR AND COMISI�N DE
INVESTIGACIONES CIENT�FICAS PCIA. BUENOS
AIRES (C.I.C.)
Near-infrared analysis (NIRT) of value enhanced
maize inbreds kernels
Corcuera V.R.1, Fern�ndez, G.1, Salerno J.C.2, Salmoral
E.M.3, Moreno-Ferrero V.4
1. Com. Inv. Cient�f. Pcia. Bs. As. 2. Inst. Gen�tica E.A. Favret-INTA 3. Fac. Ingenieria-University of
Buenos Aires 4. ETSIA-Universidad
Polit�cnica de Valencia (Spain)
The physicochemical
constitution of the maize kernel not only defines its nutritional value but
also the ability to be used in transformation industries. Kernels quality
depends on outward factors influenced by the environment, weather, soils,
temperature, rainfall as well as the management technology used during crop
growth and development aimed to obtain economically sustainable yieldings.
Inherent factors of the kernel such as the genetic background undoubtedly
influence its chemical quality and may be modified in profit of the chemical
constitution and so achieve new germplasm with excellent attributes related to
industrialization and nutritional value.
During
the growing season 200//09, in the location of Virrey del Pino, province of
Buenos Aires (34�49�57��S, 58�43�23��W; 20 masl) a complete randomized block
design field trial with three replicates including fourty-four inbreds of which
five were testers was sown.
Plant density at harvest was 71,500 plants/ha. The materials generically termed
CIG based on their endosperm attributes can be grouped as: I. Modified starch, high amylopectin content
maize (waxy), II. High-quality protein maize (HQP), III. High-quality
protein and modified starch maizes
(double mutants or DR), IV. Soft and starchy endosperm
(SE), V. Hard and vitreous
endosperm maize (VE).Only kernels obtained by hand pollination (selfings or
sib�s) were analyzed to prevent xenia particularly on oil content. The kernels,
after harvest, were kept in a cold camera until analysis. The gross chemical
was determined using an infrared spectrophotometer model Foss Infratec 1241
Grain Analyzer to quantify through a non-destructive assay proteint content
(%), starch content (%) and oil content (%). Two 60 g samples of each genotype
were analyzed and their results were averaged to obtain the final values. The
simple correlation coefficient (Pearson)
among the different chemical components was estimated.
The Table
enclosed summarizes the information relative to the chemical composition of
each inbred determined via NIRT. Whether in average, the oil content of maize kernels
is relatively low and ranges from 3 to 5%, usually the varieties most commonly
commerced around the world only have 3.0 to 3.5% oil. According to data published by ILSI and
based on samples taken worlwide (Source= ILSI Crop Composition Database
version 2.0; www.cropcomposition.org)
maize oil content varies from 1.74 to 5.56% but if it is only considered
the maize produced in Argentina the rank is about 2.68 to 5.56%. Instead,
MAIZAR (Argentine Maize Association) eventually reported that the oil content
measured by NIRT technology on 48 commercial hybrids sampled within the limits of
the ZMT and the southeastern area of the Province of Buenos Aires during the
growing season 2004/05 ranged from 3.9 to 6.5%. Taking in count the information
published by ILSI and MAIZAR but particularly the recommendation of the U.S.
Grain Council (1999), all the inbreds with 6% or higher oil content, amongst
those evaluated, were characterized as high oil maize (HOC). So, according to this criteria, the
29,5% (13/44) of the genotypes analyzed may be considered HOC. The oil content
of the fourty-four inbreds varies from 4.4 to 8.2% whilst the environment media
for the trait was 5.7%. The inbred CIG18 has the highest oil content (8.34%)
followed by CIG52 (7.3%) and CIG30 (7.1%).
In
general, maize protein content varies deeply according to genotype, production
environment, sampling and calculation factors used to convert N into protein. Maize
as the other cereal crops is relatively poor in kernel protein content as
usually varies from 8.0 to 11.0% according to FAO reports. ILSI Argentina,
estimated an average protein content of about 9.5% based on 109 commercial hybrids
sampled in the provinces of Buenos Aires and C�rdoba between 1999 and 2001. This
value is coherent with others published in the Argenfoods database, (Universidad
Nacional de Lujan, 2002). The inbreds included in the Table enclosed showed an
average protein content ranging from 8.9 to 13.3%. The 61.4% of the inbreds surpassed
the upper limit for protein content reported by FAO as they showed values
ranging from 11% to 13.3%. The highest kernel protein content was shown by the
waxy inbred CIG1 (13.3%) followed by the double mutant CIG38 (13.2%), the hard
endosperm inbred CIG32 (13.1%) and the waxy inbred CIG8 (12.8%).
Kernels
starch content ranged from 65.5 to 72.9% for the CIG inbreds, being the
environment average for the trait 69.5%. The average starch content of these
inbreds is coherent with the values published by INTA Pergamino (Technical
report 320, 1999) that points out an average of 70.6% and values ranging from
67.8 to 73.4%. Similar values were
also communicated by the National Food Office in 2007 as reported that
argentine maize varieties have an average starch content of 71.3% (range= 64.0
to 78.0%) which is very close to the 72.0% reported by FAO in 1993. Other
contrymen authors like Borr�s et al. in 2002 (Crop Sci. 42:781-790) found a range between 65.0 to 70.0% for
kernel starch content in commercial hybrids grown in Argentina. Our results
indicate that the highest kernel starch content belongs to the waxy
inbred CIG8 (72.9%) followed by the starchy inbred CIG42 (72.5%) and the double
mutant CIG42 (72.2%).
Finally, Pearson�s
correlation coefficients among oil, starch and protein content were calculated.
The results suggest once more, as in previous MNL reports, that there is not a
significant association between oil and protein content (r= -0.03; � Student�s t= 0.17) although negative and highly
significant associations (p: 0.01)
were found between oil and starch content (r=
-0.64; � Student�s t= 5.34) similarly
to reported by Wassom et al.,
2008 (Crop Sci. 48:243-252) and also between protein and starch
content (r= -0.43; � Student�s t= 3.07).
Those inbreds yielding more than 6.0% oil and
considered as HOC genotypes could be used as male progenitors in future
crossings. Similarly, inbreds with 12.0% or more protein content are suitable
to be used as females in future breeding according to the protein inheritance
model proposed by Corcuera and Naranjo in 1995 (Proc. of the III Reuni�n Latinoamericana and
XVI Reuni�n de la Zona
Andina de Investigadores en Ma�z,
Tomo II, pp.: 855-864, Cochabamba-S. Cr�z de la Sierra, Bolivia).
The
results obtained easily demonstrate that many of the CIG inbreds analyzed
overcome the average protein, starch and oil content reported for these
chemical constituents of the maize kernel by several authors or organizations
on the basis of national or worldwide varieties.
|
|
|
% OF |
||
|
INBRED |
TYPE |
OIL |
PROTEIN |
STARCH |
|
CIG1 |
Waxy |
5,5 |
13,3 |
67,5 |
|
CIG4 |
Waxy |
5,1 |
10,8 |
70,5 |
|
CIG6 |
Waxy |
5,8 |
12,0 |
68,4 |
|
CIG7 |
Waxy |
5,7 |
11,2 |
70,5 |
|
CIG8 |
Waxy |
4,7 |
12,9 |
72,9 |
|
CIG9 |
Waxy |
4,7 |
12,2 |
70,5 |
|
CIG10 |
Waxy |
5,7 |
10,6 |
71,3 |
|
CIG11 |
Waxy |
5,5 |
12,1 |
71,9 |
|
CIG12 |
Waxy |
5,5 |
10,7 |
71,6 |
|
CIG13 |
Waxy |
4,6 |
10,2 |
71,4 |
|
CIG15 |
Waxy |
6,4 |
11,0 |
69,2 |
|
CIG41 |
Waxy |
6,2 |
11,5 |
68,3 |
|
CIG49 |
Waxy |
5,2 |
11,5 |
69,3 |
|
CIG16 |
HQP |
5,8 |
11,3 |
69,9 |
|
CIG17 |
HQP |
5,8 |
11,5 |
70,1 |
|
CIG18 |
HQP |
8,2 |
10,6 |
67,3 |
|
CIG20 |
HQP |
6,2 |
11,5 |
66,7 |
|
CIG23 |
HQP |
6,1 |
10,6 |
69,0 |
|
CIG34 |
HQP |
4,7 |
11,4 |
70,3 |
|
CIG35 |
HQP |
5,1 |
11,8 |
69,6 |
|
CIG45 |
HQP |
6,3 |
11,2 |
68,2 |
|
CIG46 |
HQP |
5,2 |
11,6 |
69,3 |
|
CIG56 |
HQP |
7,0 |
11,1 |
68,0 |
|
CIG57 |
HQP |
5,3 |
12,4 |
67,7 |
|
CIG27 |
DR |
5,7 |
11,3 |
69,8 |
|
CIG29 |
DR |
5,2 |
12,0 |
68,9 |
|
CIG30 |
DR |
7,1 |
10,4 |
68,5 |
|
CIG36 |
DR |
4,7 |
12,1 |
69,3 |
|
CIG38 |
DR |
5,7 |
13,2 |
67,7 |
|
CIG39 |
DR |
6,0 |
11,2 |
68,6 |
|
CIG40 |
DR |
6,1 |
9,5 |
69,9 |
|
CIG42 |
DR |
4,4 |
8,9 |
72,2 |
|
CIG43 |
DR |
5,9 |
10,1 |
68,9 |
|
CIG44 |
DR |
6,2 |
10,6 |
69,5 |
|
CIG47 |
DR |
5,4 |
10,6 |
69,9 |
|
CIG50 |
DR |
5,6 |
10,2 |
71,7 |
|
CIG52 |
DR |
7,3 |
12,1 |
65,5 |
|
CIG55 |
DR |
6,0 |
9,6 |
69,7 |
|
CIG48 |
SE |
5,8 |
11,7 |
67,8 |
|
CIG51 |
SE |
5,0 |
9,7 |
72,5 |
|
CIG53 |
SE |
4,6 |
10,1 |
71,9 |
|
CIG54 |
SE |
4,7 |
10,4 |
70,6 |
|
CIG32 |
VE |
5,8 |
13,1 |
67,9 |
|
CIG37 |
VE |
5,5 |
12,5 |
68,4 |
|
average |
5,7 |
11,2 |
69,5 |
|
|
minimun
value |
4,4 |
8,9 |
65,5 |
|
|
maximun
value |
8,2 |
13,3 |
72,9 |
|