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100			_aSamsuddin Z
245		0	_aCorrelation studies on photosynthetic rates, girth and yield in Hevea brasiliensis
260			_bJournal of Natural Rubber Research _c1987
300			_a46-54
520			_aCorrelation studies were carried out using photosynthetic rates (PR) of two-whorl buddings raised from budded stumps in a controlled growth chamber and yield and growth parameters of mature buddings from field trials. Positive correlations between PR and yield over five years (MY) were found. No correlations were, however, detected between PR and mature growth parameters i.e. girth at opening (GO), girth at fifth year of tapping (GC) and girth increment (GI). The correlations between MY and GI or GC were negative and significant. Among the growth prarameters, significant positive correlations were found between GO and GC, GC and GI but there was no correlation between GO and GI. Multiple regression studies of PR on MY, GO, GC or GI suggest that MY was the only dominant and significant variable accounting for 22;of the variation in PR. Growth parametersl do not appear to give significant positive predictive power for PR. When MY was used as the deependent variable, with GO, GC and GI as the independent variables, the coefficients of multiple determination (R2) varied from 0.31 to 0.57. PR showed some additional contribution (significant at P < 0.1) when considered together with growth parameters to account for MY. The significance of these results is discussed in relation to the usage of PR in early selection for yield in Hevea.
650			_aGirth
650			_aHevea brasiliensis
650			_aYield
700			_aTan H
700			_aYoon P K
942			_cJS
999			_c56410 _d56410