Relationship between some growth parameters and vigour of polyembryonic mango genotypes.
Manish Srivastav, Mahesh Kumar, Dubey A. K., Singh A. K.
Author Affiliation: Division of Fruits and Horticultural Technology, Indian Agricultural Research Institute, New Delhi 110 012, India.
Indian Journal of Horticulture 66 : 438-444
Abstract : An experiment was carried out to investigate the relationships of different growth parameters with vigour indices of polyembryonic mango plants. Nucellar plants of 16 polyembryonic genotypes, viz. 'Bappakai', 'Carabao', 'Cecil', 'Chandrakaran', 'Combodiana', 'Kerala-1', 'Kerala-3', 'Kerala-5', 'Kurukan', 'Muvandan', 'Mylepelian', Olour', 'Peach', 'Sabre', Turpentine' and 'Vellaikolamban' were used for the study. Vigour index-I (V-I) consider the length and vigour index-II (V-II) is based on dry weight of seedling. Growth parameters, viz. shoot growth, leaf growth, root growth and fresh and dry mass production were determined and relationship was established between different growth parameters and vigour index-I and vigour index-II. The vigour index-I and vigour index-II had linear positive relationship with shoot length and internodal length. However, shoot diameter showed low degree of association with vigour index-I (R2=0.18) and vigour index-II (R2=0.38) among 16 polyembryonic mango genotypes. The relationship between leaf growth and vigour indices showed very low degree of association with vigour indices. Root growth parameters like root length and root diameter had significantly higher positive regression relationship with vigour indices. The fresh and dry mass production of sixteen polyembryonic mango genotypes showed unique trend and all parameters showed comparatively higher association with vigour index-II than vigour index-I. Furthermore, vigour index-II had high degree of positive relation with shoot fresh weight (R2=0.89), shoot dry weight (R2=0.96) and root dry weight (R2=0.85). The results suggest that growth parameters, viz. shoot length, intermodal length, root length, root diameter, and fresh and dry weight of shoot and dry weight of root are reliable criteria for determination of vigour in mango at nursery stage.