Response of turmeric (Curcuma domestica Val.) to in vivo and in vitro pollination

Seed set and development were obtained through in vivo pollination in three combinations of short duration turmeric cultivars and these were not observed in crosses of medium duration cultivars and short x medium duration cultivars. The fruit developed after in vivo pollination was a thick walled trilocular capsule. It took 20-22 days for development and ripening. Arilled seeds are triangular with two seed coats. The seeds are filled with massive endosperm and the embryo is seen oriented towards the chalazal end of the seed. In the in vitro pollination studies, culture establishment and ovule development were obtained in half strength MS + NAA 0.5 mg l-1 with BAP and kinetin at 1 mg l-1 each. Among the various methods of pollination tried, ovule seed-l development was observed in the intra ovarian, placental and modified placental pollination techniques. In the in vitro developed seed, the endosperm development was not complete. The aforesaid in vitro techniques need refinement with respect to medium and other requirements for the germination of in vitro produced seeds. &nbsp

Response of turmeric (Curcuma domestica Val.) to in vivo and in vitro pollination

Seed set and development were obtained through in vivo pollination in three combinations of short duration turmeric cultivars and these were not observed in crosses of medium duration cultivars and short x medium duration cultivars. The fruit developed after in vivo pollination was a thick walled trilocular capsule. It took 20-22 days for development and ripening. Arilled seeds are triangular with two seed coats. The seeds are filled with massive endosperm and the embryo is seen oriented towards the chalazal end of the seed. In the in vitro pollination studies, culture establishment and ovule development were obtained in half strength MS + NAA 0.5 mg l-1 with BAP and kinetin at 1 mg l-1 each. Among the various methods of pollination tried, ovule seed-l development was observed in the intra ovarian, placental and modified placental pollination techniques. In the in vitro developed seed, the endosperm development was not complete. The aforesaid in vitro techniques need refinement with respect to medium and other requirements for the germination of in vitro produced seeds. &nbsp

Variability in fruit characteristics of nutmeg (Myristica fragrans Houtt.) under Kerala conditions

Forty one accessions of nutmeg collected from diverse locations of Kerala of age 15 years were evaluated at Kerala Agricultural University, Thrissur during 2012–14. Among these accessions, 38 were females and three were monoecious. The accessions were evaluated based on 17 fruit characters recorded from two trees per accession during two consecutive bearing seasons. The statistical parameters viz., mean, range, phenotypic coefficient of variation (PCV), genotypic coefficient of variation (GCV), heritability (H2), genetic gain (GG) and genotypic correlation coefficients were calculated. High PCV and GCV were observed for the characters such as fruit weight, mace weight, mace volume, dry nut weight, kernel weight, fruit volume and number of fruits per tree. Heritability was high for all the characters except shell thickness. High GCV coupled with high heritability in the characters indicated the scope for yield improvement through selection based on these characters. Genetic gain was the highest for number of fruits per tree (144.3%) followed by mace characters viz., fresh and dry weight as well as volume of nut. Fruit weight was also significantly and positively correlated with fruit breadth, fruit volume and thickness of pericarp. Based on the results, accessions such as Acc. 9, Acc. 8 and Acc. 22 were found promising with respect to the economic characters viz., mace weight, nut weight, kernel weight and number of fruits per tree. These accessions can be used in further crop improvement programmes on nutmeg. &nbsp

High yielding nutmeg (Myristica fragrans Houtt.) varieties: a farmer-centric research approach to select superior trees

A comprehensive survey was conducted all along the nutmeg-growing region of Kerala state to locate superior clones of nutmeg, by employing Participatory Varietal Selection (PVS) method. Twenty-nine superior accessions were identified through mother tree characterization for four consecutive years. The characterized clones were female and produced fruits ranging from 628 to 2250 tree-1 year-1, dry nut weight varied from 3.27 g to 15.37 g, and assorted dry mace weight was from 0.35 g to 4.80 g. Genetic variability analysis revealed the high heritability with high genetic advance as per se mean (dry mace weight 76.30%, dry kernel weight 71.37% and the number of fruits tree-1 73.24%) which signifies the advantage of simple selection method of breeding. Based on the economic importance of yield contributing characteristics, five superior clones out of twenty-nine mother trees evaluated and have been released as KAU- farmer’s varieties. All the superior trees identified based on yield traits had appreciable quantities of volatile oil (1.63-12.25% in nut; 3.31-16.97% in mace), oleoresin (17.60-41.77% in nut; 13.00-30.50% in mace) and fixed oil (22.45-40.70% in nut) in their nuts and maces as well as myristicin, elemicin, safrole and sabinene in the volatile oils. The characteristic features of mother trees and released varieties are discussed in this paper, and further, these varieties are recommended for commercial cultivation under tropical moist, humid climate conditions