Evaluation of Sugarcane Genotypes Under Irrigation Based on Genetic Variations and Heritability for Agronomic Traits at Early Selection Stage in Ferké, Ivory Coast

Abstract

The objective of the study was to determine the best performing sugarcane genotypes tested at early selection stage under sprinkler irrigation, in comparison with a check variety (R579). The experiment was designed following a randomized complete block (RCB) with 21 cane genotypes in three replications. Each plot consisted of five dual rows of ten meters with 0.5 and 1.90 m of inter-row spacing, i.e. 95 m 2 per plot and about 6,000 m 2 for the whole experiment. It was carried out on a commercial sugarcane plantation of Ferké 2 located in the northern part of the country, over two seasons (plant cane and first ratoon) as an early-season crop from, November 18, 2016 to November 15, 2018. Over each micro-plot, data based on different agro-morphological traits were collected at harvest from three central dual rows. The study showed that most relevant traits in genotype clustering were related to juice quality (recoverable sucrose, sucrose content, purity), yields and yield components (millable stalk number/ha, stalk height, stalk diameter, internode number). Based on sugar yields, four genotypes equivalent to the check (R579), namely KQ228, R97-6177, R99-4064 and KQ236, were found promising for the next advanced selection stage with, respectively, 19.2, 17.7, 17.3 and 16.9 t sugar/ha. Their cane yield performances ranged from 147.7 to 170.8 t/ha compared to 170.7 for the check and belong to 3 clusters genotypes over the eight determined. Not only sugar yield, but also flowering rate, stem borer infestation rate and number of tillers per hectare were found as the most relevant agro-morphological traits in the genetic variation of sugarcane genotypes tested.

Genetic Variation and Heritability for Juice Quality and Yield Traits in Selection of Sugarcane Genotypes under Irrigation at Early Stage in Ferké 2 Sugar Estate of Northern Ivory Coast

“…Nevertheless, productivity improvements in sugarcane have been almost nil in the past three decades, and production statistics exhibit decreased yields globally [1]. In most cases, increased sugarcane production used to be explained by the expansion of land surface rather than increase in yield [2,3]. Commercial sugarcane varieties under cultivation are complex polyploids, which heterozygous nature has resulted in generations of higher genetic variability.…”

“…Commercial sugarcane varieties under cultivation are complex polyploids, which heterozygous nature has resulted in generations of higher genetic variability. Information about the nature and magnitude of variability present in genetic materials is of prime importance for breeders to conduct effective selection programs [3][4].. Genotypic and phenotypic coefficients of variation, together with heritability and genetic advance, are key elements to improve any agronomic trait of sugarcane, as this would help in knowing whether or not specific objectives targeted could be achieved from a given crop material [3][4][5].…”

“…Sugarcane used to be the major source of sugar production in Ivory Coast and many tropical countries, where this crop used to be traditionally cultivated mainly for chewing purpose by smallholder farmers. Commercial sugarcane production in Ivory Coast started in 1974 at Ferké 1 plantations on about 5,500 ha [3]. Nowadays, sugarcane is grown on around 30,000 ha and the four sugar mills located in three different regions of the country produce, on yearly basis, about 200,000 t sugar [3,6].…”

“…Commercial sugarcane production in Ivory Coast started in 1974 at Ferké 1 plantations on about 5,500 ha [3]. Nowadays, sugarcane is grown on around 30,000 ha and the four sugar mills located in three different regions of the country produce, on yearly basis, about 200,000 t sugar [3,6]. This production does not meet the domestic consumption, which is estimated to around 240,000 t. The production deficit is being offset by imported sugar, to alleviate the gap between supply and demand of sugar.…”

“…Understanding associations between traits is of great importance in breeding and selection studies, particularly for low heritability or hardly measuring attributes [6,[8][9][10], like cane and sugar yields, recoverable sucrose, number of tillers/ha, and number of attacked internodes by stem borer. Genetic relationships between important attributes in studying sugarcane populations through breeding and direct selection are crucial to understand how changes made by selecting one character may affect the others [3,6,[11][12]. This knowledge can be used when determining effective selection strategies for particular traits in a sugarcane breeding program [6,13].…”