scholarly journals Genetic Testing of Inbred Lines and Single Cross Hybrids against Fusarium Stalk Rot Caused by Fusarium moniliforme in Maize (Zea mays L.)

Author(s):  
R. Archana H. C. Lohithaswa ◽  
R. Pavan B. N. Swathi ◽  
N. Mallikarjuna

Globally, Maize (Zea mays L.) is a third major cereal food crop. It is a multipurpose crop with 26% of its production is used as food by human beings. Maize is known as “queen of cereals”, because of its high genetic yield potential, efficient utilization of radiant energy and wider adaptability. About 65 different phytopathogens affect the maize production in different stages of life cycle. Among which Fusarium moniliforme is one such soil borne pathogen causes Fusarium stalk rot (FSR) disease that ultimately reduces maize yield potential over the world. In any breeding program, screening and genetic testing of available germplasm resources against pathogens is necessary to prevent yield losses. Hence, the present research screened around 114 maize inbred lines and 45 single cross hybrids (SCHs) against FSR under artificial epiphytotic conditions. Among 114 inbreds, only four inbreds viz., CM 202, 10878, MAI-759 and MAI-766 (mean disease score of 3-4) showed moderately resistant reaction and out of 45 SCHs, only one hybrid combination i.e., MAI329 × CM202 (mean disease score was 2.60) exhibited resistance reaction against Fusarium stalk rot. Nevertheless, these resistance sources could be utilized in maize breeding programs for obtaining high yielding cultivars with resistance towards FSR disease.

1971 ◽  
Vol 13 (4) ◽  
pp. 649-655 ◽  
Author(s):  
R. Bruce Hunter ◽  
L. W. Kannenberg

The extent of heterosis observed in a single cross hybrid has generally been reported to be a function of the genetic diversity of its inbred components. We used isozyme variability as an indicator of genetic diversity. Fifteen inbred lines of maize (Zea mays L.) were characterized for esterase, amylase, leucine aminopepridasc, catalase, alcohol dehydrogenase and peroxidase isozymes. Differences in these systems were used to calculate a diversity index (DI). The DI for an inbred pair represented the number of isozymes that were dissimilar in the two inbreds. Hybrids produced from inbred pairs with higher DI's outyielded those with low DI's. However, the correlation between grain yield performance of the single cross hybrids and DI was low (r = 0.09) and not significant. Hence, the DI, as used here, is of very limited predictive value.


2016 ◽  
Vol 4 (3) ◽  
pp. 359-364
Author(s):  
S. Subedi ◽  
B. Paudel ◽  
B. Bhandari

For development of single cross hybrids in maize, developed inbreds must be evaluated for the determination of highly heterotic inbred combination (HIC). One of the best methodologies for determination of heterotic inbred combination can be multivariate analysis (MVA) or scales of phenotypic distance or dissimilarities or cluster diagram. For it, inbred must be observed for useful trait measurements. Accordingly, an experimental evaluation was conducted including promising 55 inbred lines of winter maize planting on Sep 3, 2015 at National Maize Research Program Rampur, Chitwan Nepal (NMRP/NARC). The distant inbred lines were determined through MVA. Single plot research technique was done where each inbred line was provided with 2 rows of 20 plants each. Data were taken for fifteen traits. By the use of MINITAB software, the data was analysed. Graphics of principle component analysis (PCA) cluster diagram (CD or dendogram) were constructed and phenotypic dissimilarities are examined.The distant inbreds RML-8, RML-88, RML-13, RML-103, RML-89, RML-102, RML-11, RML-17, RML-83,RML-98,RML-85,RML-86,RML-94 and RML-28 could be crossed with RML-75,RML-6,RML-68,RML-36 and RML-32 which could be used as tester inbred for heterotic hybrid combination. Similarly, RML-98, RML-85, RML-86, RML-94 and RML-28 could be crossed with RML-24, RML-96 and RML-99.  Though distant inbred, RML-104 had less ASI but it wasn’t feasible to use for crossing due to higher anthesis tasseling interval.Int J Appl Sci Biotechnol, Vol 4(3): 359-364


1962 ◽  
Vol 42 (2) ◽  
pp. 302-307 ◽  
Author(s):  
N. J. Whitney ◽  
C. G. Mortimore

In bio-assay tests ether extracts of the roots and of the stalks of both resistant and susceptible corn inbreds inhibited the growth of Fusarium moniliforme Sheld. and Gibberella zeae (Schw.) Petch, the level of inhibition varying over the season. However, the extracts of the resistant and susceptible inbreds did not differ consistently in their ability to inhibit fungus growth on any given date. Thus, this bio-assay method cannot be used to evaluate inbreds for resistance to root and stalk rot.


2021 ◽  
Vol 13 (2) ◽  
pp. 78
Author(s):  
L. Musundire ◽  
J. Derera ◽  
S. Dari ◽  
A. Lagat ◽  
P. Tongoona

Grain yield potential of new maize hybrid varieties across target environments contributes to the uptake of these varieties by farmers. Evaluation of single-cross hybrids developed from test crossing introgressed inbred lines bred for three distinct environments to elite tropical inbred line testers was carried out. The study’s objective was to assess grain yield stability and genotype adaptability of the single-cross hybrids across South African environments relative to adapted commercial hybrid checks. One hundred and twenty-two introgressed inbred lines developed using the pedigree breeding program were crossed to four tropical elite inbred line testers using line × tester mating design to obtain 488 experimental single cross hybrids. Subject to availability of adequate seed for evaluation, a panel of 444 experimental single-cross hybrids was evaluated using an augmented design in two experiments defined as Population A and B for the study’s convenience in South African environments. Data for grain yield (t/ha) performance for experimental single-cross hybrids and commercial check hybrids in Population A and B across environments and individual environments identified experimental single-cross hybrids that had significant comparable grain yield (t/ha) performance relative to best commercial check hybrid (PAN6Q445B) on the market. The selected experimental single-cross hybrids 225, 89, 246 and 43 (Population A) and 112 (Population B) also had a better average rank position for grain yield (t/ha) relative to best commercial check hybrid. These selected experimental single-cross hybrids had a grain yield (t/ha) advantage range of 0.9-6.7% for Population A and 7.3% for Population A and B, respectively, relative to the adapted commercial check hybrid. GGE biplot patterns for which won-where for Population A indicated that at Potchefstroom Research Station and Ukulinga Research Station experimental single-cross hybrids 127 and135 were the vertex (winning) hybrids. Cedera Research Station did not have a vertex hybrid for Population A. For Population B, experimental single-cross hybrids 112, 117 and 18 were the vertex hybrids at Cedera Research Station, Ukulinga Research Station and Potchefstroom Research Station, respectively. Experimental single-cross hybrid 257 was identified as ideal genotype for Population A, while experimental single-cross hybrid 121 in Population B was the ideal genotype. Ideal environments were also identified as Ukulinga Research Station for Population A, and Cedera Research Station for Population B. Average-environment coordination (AEC) view of the GGE biplot in Population A indicated that experimental single-cross hybrids 1 was highly stable across environments. In comparison, Population B experimental single-cross hybrid 161 was highly stable across environments. In conclusion, selected single-cross hybrids in the current study can also be advanced for further evaluation with a possibility for identifying high yielding and stable single-cross hybrids for variety registration and release in target environments in South Africa.


Sign in / Sign up

Export Citation Format

Share Document