Flowering Behaviour of Sugarcane Genotypes from Different Agro Climatic Zones of India

Abstract

Intensive flowering and good seed set are the two important parameters for generating more genetic variability which is the foundation for national sugarcane varietal development programme. Five hundred and forty-eight parental clones including those representing five different agro climatic regions of sugarcane cultivation in the country being maintained along with 22 foreign hybrids at National Hybridisation Garden were studied for their flowering behaviour at Coimbatore. Among the parental clones studied, 37 % of the clones were found as regular flowerers that flowered during all the 5 years of study. Around 23 % each were belonging to the category of frequent flowers and timid flowerers. About 7 % of parents were found rare flowers and 9 % were belonging to non-flowerers. Among the different zones, North Central Zone had more number of frequent flowerers followed by North West Zone. More number of frequent flowerers from the breeding centres of tropical region may be attributed to the presence of higher number of Saccharum spontaneum alleles in them. Consistent pattern of flowering was observed in the subtropical clones. The altitude from which selection was made did not appear to have any direct influence on flowering. The clones from sub-tropical region flowered early followed by the tropical clones. The maximum number of clones was flowered during first fortnight of November. None of the clones from North East Zones recorded the 100 % flowering propensity but some from other four zones viz., Peninsular (8.02 %), North West (12.50 %) and East Coast (1.75 %) and North Central Zone (15.00 %). Wide range of flowering propensity from 1.28 to 100 % was observed in the clones from North West Zone while relatively narrow range 5.88–92.87 % in North East Zone. The clones with 100 % flowering propensity were mostly from subtropical region which may be due to the presence of more genome of S. spontaneum which usually flowers freely in their original habitats and also at the established locations. Pollen fertility studies among the parents revealed that frequency of safe females were relatively higher than that of strong males. Correlation studies indicated that regularity of flowering is positively correlated with intensity of flowering.