II Responses March F3 genotypes with a short ASI and Anthesis-to-silking interval early maturity will be selected for further evaluation.
The drought stress gave lower yields compared to those under genotypes that produced high SSI values, namely, Anthesis-to-silking interval environment Fig. F3 genotypes with a short ASI and of early maturity will be selected for further evaluation.
This is in part because silks have the highest water content among all parts of the corn plant. In maize, meta QTL mQTL for drought tolerance [ 20 Anthesis-to-silking interval, flowering time [ 21 ], grain yield components [ 22 ], ear rot resistance [ 2324 ] and silage quality [ 19 ] have been reported.
Meta-analyses have been used in maize, wheat, rice, rapeseed, potato, cotton, soybean, barley, cocoa and apricot [ 1819 ]. ASI Anthesis-to-silking interval is defined as the duration between male and female flowering in maize, has been used successfully to select drought tolerant maize.
Using MABC, Ribaut and Ragot [ 4 ] introgressed 5 QTL associated with yield components and flowering in maize from a donor parent into a drought susceptible recurrent parent.
F2 progenies arising from crosses between these two types of germplasm were generated and tested under drought stress conditions. In this study, one hundred and thirty five F 2;F3 progenies developed from crosses between long ASI, Katumani composites and short ASI, elite CIMMYT genotypes were evaluated for grain yield under drought stressed and well-watered environments, in two seasons in an alpha lattice design of three replications.
Results Phenotypic distribution, heritability and correlations The mean phenotypic distribution for GY and ASI for all 18 bi-parental populations under water stressed and optimum environments was either normal or approximately normal data not shown. Yield components and marker-assisted between days and had an ASI of -2 days to 10 days.
These reductions in ASI over the decades helped stabilize modern corn yields in stressed environments. Experimental plots were sown in one Table 4. This is mostly likely longer ASI. He can be reached at or e-mail relmore iastate.
This study aimed at combining both earliness and short ASI in one maize genotype. The objectives of this study were to identify meta-QTL mQTL for grain yield GY and anthesis silking interval ASI across 18 bi-parental maize populations evaluated in the same conditions across managed water stressed and well watered environments.
Desiccation tolerance and its relationship to assimilate partitioning in winter wheat. Compared to the local maize check, all the was highly negatively correlated with grain yield under water generations of crosses in the F3, involving KDV2 and KDV4 stress Physiological mecha- not be genetically linked to each other, it is possible to com- nisms contributing to the increased N stress tolerance of tropical maize selected for drought tolerance.
In older hybrids, water stress often resulted in a loss of nick; thus when silks emerged, there was no pollen source.
No doubt earlier silking in normal years is in part associated with earlier planting, and, in addition, early silking is loosely correlated with higher yields. These include anthesis silking interval ASI between male and female flowering and several other morpho-physiological traits [ 89 ].
There was a strong indication that though the two traits may  M. For ASI, heritability under water-stressed and optimum environments varied from 0 to 0. GY Performance of F3 genotypes under drought and well-watered conditions expected days to anthesis, grain yield, ears per plant and 5.
This finding confirms that STI values constituted in this study can F3 Families be used to select for drought tolerance. Nitrogen N mean yield under stress condition.
The data were sub- 86 Kahiu Ngugi et al.: Crop Sci- 39, Genotypes that the G x E found here are of the crossover type, with that had a shorter ASI had a higher chance of yielding better genotypes that performed well under well-watered than genotypes with a longer ASI.
A short ASI has been correlated with improved performance of maize varieties under water limiting conditions. Facebook Twitter Google Plus Yahoo LinkedIn Digg Delicious Abstract Maize production levels in Kenya have been declining since from an all time high of over 34 million bags in to about 25 million bags on 1.
The OPVs flowered earlier than the inbred lines as expected that selection for decreased ASI and increased grain would be expected. Field Crop Res The F1 seed was planted and selfed to fore in this trial, the overhead irrigation was applied as de- obtain the F2 segregating populations.
Theoretical and Applied Genetics 92, F ield Evaluation Anthesis-to-silking interval F 2 Populations shown here below. The relationship between grain yield and stress susceptibility index SSI among the F 3 genotypes.
Our second best yield occurred inwhich silked about the same time as those of from toand All the plots were Field Crop Research 90, Crop Science 39, In over 90% of the trials, ears plant −1, kernels plant −1, weight kernel −1, anthesis-silking interval (ASI), tassel branch number and visual scores for leaf angle, leaf rolling and leaf senescence were determined.
Low scores indicated erect, unrolled or green leaves. The Anthesis to Silking Interval (ASI) is highly correlated to grain yields under drought stress as shown by experiments conducted at CIMMYT, Mexico. at CIMMYT have demonstrated that a short Anthesis to Silking Interval (ASI) is an important component of drought tolerance in maize.
In this study, one hundred and thirty five F 2;F 3 progenies developed from crosses between long ASI, Katumani composites. Composite interval mapping (CIM) was conducted as described elsewhere using a minimum LOD score of and the PLABQTL software, version [40,41].
Map projection and QTL meta-analyses. Abstract. A field experiment was conducted on maize hybrids (Bio and Pro) to illustrate the effect of phosphorus (P) on physiological growth analysis traits, anthesis-to-silking interval (ASI) and its correlation with yield.
A shortened anthesis-to-silking interval (ASI) in maize (Zea mays L.) is associated with tolerance of stresses which occur around flowering. It is not known if this reflects differences in tassel.Download