Chlorophyll content in make (Zea mays L.) leaves: physiological and seasonal variation

The chlorophyll content (a, b, and total), percentage and chl. a:b ratio in maize leaf varied with growth stage among cultivars and growing season (monsoon and winter). Chlorophyll a:b ratio was positively correlated with net assimilation rate (NAR), nitrogen content/plant, grain yield and crop growth period, whereas it was negatively correlated with nitrogen content of leaf, total chlorophyll, leaf area duration (LAD) and accumulated modified corn heat units(MCHU). Total chlorophyll correlated positively with leaf area/plant, LAD, leaf nitrogen content and grain yield, while negatively with NAR and crop growth duration. Chlorophyll b was found to be more sensitive to nitrogen status and age of plant, and growing seasons than chlorophyll a. The chlorophyll (a, b and total) content had a high degree of heritability and genetic advance while chl. a:b ratio had low values for these estimates.