Applicability of agronomic traits in the determination of yield of turmeric (Curcuma longa L.)

Turmeric (Curcuma longa) has gained significant attention in medicine, nutrition, and biotechnology due to its pharmacological properties and potential therapeutic applications. Since it is vegetatively propagated through underground rhizomes, the genetic improvement of turmeric is very limited. Screening for superior traits is still practiced for turmeric since it has a broad, untapped natural variation. Different agronomic traits, directly and indirectly, determine rhizome yield in turmeric. The present study reveals yield-determining traits of turmeric as described by correlation coefficients and path coefficients. The yield determinants of turmeric would be useful for selecting higher yields. Turmeric rhizomes were planted in the field, and data on eleven traits of two hundred plants were recorded. The research utilized principal component analysis (PCA) and identified three main components (PC1, PC2, and PC3), which had eigenvalues of 4.157, 3.017, and 1.992, respectively, explaining 76.385% of the total cumulative variability. Plant height is a key factor in determining yield, as it indicates a strong positive correlation and has a significant direct effect on yield. The number of secondary fingers per plant was also a considerable factor as it showed a significant positive correlation and considerable direct influence on yield. The number of mother rhizomes per plant and the length of leaf petiole could still be a viable positive trait for high-yield as they show a lower direct influence on yield. Leaf blade length is not a good criterion for yield determinants. These parameters can be utilized in future breeding programs to select high-yielding genotypes.