ABSTRACT
Screening for drought tolerance requires precise techniques like phonemics, which is an emerging science aimed at non-destructive methods allowing large-scale screening of genotypes. Large-scale screening complements genomic efforts to identify genes relevant for crop improvement. Thirty maize inbred lines from various sources (exotic and indigenous) maintained at Dryland Agriculture Research Station were used in the current study. In the automated plant transport and imaging systems (LemnaTec Scanalyzer system for large plants), top and side view images were taken of the VIS (visible) and NIR (near infrared) range of the light spectrum to capture phenes. All images were obtained with a thermal imager. All sensors were used to collect images one day after shifting the pots from the greenhouse for 11 days. Image processing was done using pre-processing, segmentation and flowered by features' extraction. Different surrogate traits such as pixel area, plant aspect ratio, convex hull ratio and calliper length were estimated. A strong association was found between canopy temperature and above ground biomass under stress conditions. Promising lines in different surrogates will be utilized in breeding programmes to develop mapping populations for traits of interest related to drought resilience, in terms of improved tissue water status and mapping of genes/QTLs for drought traits.
Subject(s)
Droughts , Zea mays/physiology , Biomass , Crops, Agricultural , Genotype , Image Processing, Computer-Assisted , Phenotype , Plant Shoots/growth & development , Plant Shoots/physiology , Quantitative Trait Loci , Water/physiology , Zea mays/genetics , Zea mays/growth & developmentABSTRACT
BACKGROUND: Enhancing the micronutrient content of staple crops such as rice will improve human nutrition and address the problem of hidden hunger globally. Rice grains consumed after polishing lack adequate amounts of micronutrients. The present study aims to reveal the effects of polishing on micronutrient content and to identify superior genotype(s) to improve yield and micronutrient content after polishing. RESULTS: AM65 exhibited the highest zinc content, and AM180 had the highest iron content, even after polishing. There was little or no difference between the genotypes for zinc content in bran, indicating a possible threshold for micronutrient accumulation in the aleurone layer. A comprehensive selection criterion called 'micronutrient productivity' was used to select for both yield and micronutrient parameters. AM65 and ARB6 showed high zinc and iron productivity indices. OsZIP4b and OsZIP6c markers showed an association with iron content on an agarose gel. Sequencing of markers revealed that OsYSL15 and OsZIP6c were associated with grain zinc content and OsZIP3b, OsMTP1a, and OsYSL4b with grain iron content. These markers can be used for selecting superior accessions. CONCLUSION: AM65 was loaded with micronutrients and manifested a positive correlation with the grain yield, and it is undoubtedly 'super elite'. Bran does not drain the grain but rather acts as gateway for micronutrient transportation to the endosperm. Micronutrient productivity is a comprehensive parameter for the biofortification of grain. © 2018 Society of Chemical Industry.
