Abstract:
Underground stubbles of sixteen genotypes after harvest of the plant crop (2012-13) left for evaluation of their ratoon during 2013-14 at RPCAU Pusa Farm, Samastipur, Bihar under low land area and grand growth phase coincides with water-stagnation depth 40-45 cm for 2 to 3 month to know the extent of genetic divergence for productive traits and identification of better ratooner. The traits
namely, number of Shoots at 120 days, plant height at 150, 240 and 330 days (at harvest), Cane diameter at harvest, number of millable cane at harvest, single cane weight at harvest, Brix % at 9 & 11 month, Pol % in juice at 9 & 11 month, purity % at 9 & 11 month, CCS Per cent at harvest, cane yield at harvest and CCSt/ha were showed highly significant variation. Ratoon of all the sixteen genotypes differed significantly with regard to the traits studied and displayed marked divergence and grouped into five clusters following Tocher’s method, Cluster I had seven genotypes
namely, BO154, CoP092(CoP09437), CoP 02061(CoP 2061), CoP 091, CoP 111, BO155 and BO141 followed by Cluster II containing six
viz. CoP 04181, BO146, BO91, CoSe 96436, CoP 081 & CoLk 94184 while Cluster III, IV and V were monogenotypic, comprising single genotype BO 147, BO 153 and CoX 07067, respectively. Maximum value for inter cluster distance was observed between cluster II and V (1050.77) followed by cluster III & V (817.02), cluster III & IV (623.84), cluster II & IV (567.85), cluster I & V (419.80) and between cluster I & II (319.39). The highest contribution towards genetic divergence was exhibited by pol % in juice at 9 month stage (45.0) followed by brix % at 11 month (15.0), CCS per cent at harvest (10.83), purity % at 11 month (8.33), single cane weight (7.50), pol % in juice at 11 month (5.0), plant height at 240 days (4.17), purity % at 11 month (2.50) and rest of the other traits had less than one. The genotype CoP 09437 had maximum value for cane yield (87.54 t/h) and CCSt/ha(10.0 t)/ha, as well as it performed top rank on the basis of percentage increase over both the checks (27.39% over BO91 and 17.85 % over BO147 for cane yield while for CCS t/ha 53.37% over BO91 and 31.41 % over BO147) followed by BO 154, CoX 07067 and CoP 2061, therefore these genotypes were Identified as better ratooner among the 16 genetically diverse genotypes under water-logging condition which would be cultivated in water-logging areas of Bihar to enhance the productivity and sugar recovery as well as it can be utilized as a water logging tolerant parent in sugarcane crossing programme.