PhD Thesis      [Total: 1 ]


Mahmoud Mohamed Ali Ebid, 2015


ABSTRACT Mahmoud Hamdy Mohamed Ali Ebid: Family Selection in SugarCane Populations as Affected by Genotypes X Environments Interaction. Unpublished Ph.D. Thesis, Department of Agronomy, Faculty of Agriculture, Ain Sham University, 2015. The present investigation included two experiments were carried out during three growing seasons (2011/12 to 2013/14) at three locations, i.e. Kom-Ombo Agricultaral Research Station, Aswan Governorate latitude 24° 15? N (L1), Mattana Agriculture Research Station, Luxor Governorate latitude 25o 36? N (L2) and Shandweel Agricultural Research Station, Sohag Governorate latitude 26o 33? N (L3). The objectives of this study are to select the most promising cane clones that could outyield the commercial check cultivar GT.54-9 through study the performance of five sugarcane populations consisted of 206 clones at Kom-Ombo, Mattana and Shandweel locations along with the commercial cultivar GT.54-9. Based on results obtained from the first experiment a total of sixteen clones were selected from the five populations. In the first experiment (base populations) it could be reported that the high broad sense heritability coupled with high genetic advance for single stalk weight, number of millable canes and Brix% indicates that clones number 2, 22 (population I); 8, 12, 16. 18 (population II); 4, 13 (population III); 4, 5, 6, 9, 13, 32 (population IV); 4 and 31 (population V) were most greatly superior to the other clones compared with check variety. Based on the selected clones, it was suggested to advance clone No. 18 in population II for further selection stages at Shandweel as well as clone 13 in IV at Mattana, in addition to clones No. 2 and 22 in I and 13 in IV at Kom-Ombo, its had a high cane and sugar yields. Significant differences among the genotypes for all the traits were observed. Genotype × location (G×L) interactions were significant (p ? 0.01) for stalk height, stalk weight and cane yield. In the plant cane and 1st ratoon, high broad-sense heritability (h2) was detected for number of millable canes (0.96 and 0.93), single stalk weight (0.90 and 0.88), stalk diameter (0.80 and 0.86) and stalk height (0.82 and 0.79) respectively indicating that these traits could be easily selected. Highest expected genetic gains were recorded in stalk weight and number of millable canes. All traits had high to moderate genetic correlations with cane yield. On the average, genetic correlations were higher than phenotypic correlations. The study suggests that evaluation of sugarcane clones in many locations as opposed to crop years would be satisfactory. In view of their high GCV, broad-sense heritability and expected genetic advance, a selection strategy based on single stalk weight and number of millable canes could lead to improvement in cane yield. Key Words: Sugarcane, Family selection, Populations, Clones, Locations, G x E interaction, Genetic advance, Broad sense heritability, Genotypic and phenotypic variances.