TY  - BOOK
AU  - Chaudhuri D
AU  - Mondal G C
AU  - Nazeer M A
AU  - Reju M J
AU  - Thapliyal A P
TI  - Effct of altotude on rubber yield and its components of some Hevea clones under two agro-eco-regions of India
PB  - Proceedings of the 15th Plantation Crops Symposium, PLACROSYM XV, 10-13 December 2002, Mysore .pp.348-355.
KW  - Agro-eco-regions
KW  - Hevea clones
KW  - Rubber yield
N2  - The study was conducted in five Hevea clones (RRII 105, RRII 118, RRII 203, RRIM 600 and PB 235) planted in 1985. The trial was laid out in a completely randomized block design with 50 replications each at Sorutari Farm (Lat.:26 o. 35N, Long: 90 o52E, altitude 50 to 105 m above MSL) under Kamrup district of Assam at Ganolgre farm, Tura, West Garo Hills, Meghalaya (Lat.:26 o. 26N, Long:90o91E, altitude 600 m above MSL) under two agroecoregions No:15 and 17 respectively. The genotypic variation of the clones interacted with the environmental factors, variability of which is pronounced in altitudes and months of the year. Altitude had significant correlation with dry rubber content, rubber yield, latex yield while rubber yield showed significant correlation with latex yield and plugging index erspectively. The relationship between dry rubber content and girth increment was highly significant. Plugging index was significantly correlated with latex yield. The suitability of initial and final models with regard to each clone for predication of rubber yield is confirmed by the significance of regression indices which was evident by the lesser value of residual sum of squares than the regression sum of squares and high significance of the  F statistics. Moreover, in each case the regression coefficients being nearly are also indicative of the fitness of the model. In case of all the clones, the initial models appeared to give better prediction of a yield component and environment model as was observed by the higher value of realized multiple regression coefficients. Neverthless, the final model determined that altitude was a deciding factor towards rubber yield in case of only clones RRII 105, RRII 118 and RRIM 600 while for the clones RRII 118 and PB 235, the effect of altitude was almost negligible
ER  -