Abstract:Two O. indica hybrid rice cultivars, Xinongou 1 characterized with high tiller and Gangyou 725 characterized with high yield potential, were used to investigate the compensation capacity of tillering and production of main stem nodes by artificially specific tiller removal treatment in the initial tillering stage under population condition. The tiller removal treatments included the early tiller emerge that doesn't remove any tiller, the middle tiller emerge that removes the first primary tiller, and the later tiller emerge that removes the first and second primary tillers. The result showed that the canopy light distribution is an important environment factor affecting the compensational capacity of tillering, and the tillering compensational capacity of upper node group was higher than that of middle and low node group under enough water and fertilizer. Compared with the early tiller emerge treatment, in the morphological characteristics, the later tiller emerge treatment reduced the leaf area index, improved the light intensity or quality of stem base, delayed the shade escape, and promoted the differentiation and growth of upper node tiller, increased the growth potential and effective tiller multiple in the upper node group and increased the single stem leaf area in the heading stage. However, the tiller development characteristic of upper node group reduced the effective panicles and leaf area index, so the absolute compensation capacity was low. In the ecological and physiological characteristics, the canopy light distribution, chlorophyll and protein content increased, and the activity of cell protective enzymes (superoxide dismutase, SOD; catalase, CAT) drop slowly, and the leaf senescence rate delayed, whereas the light penetration loss rate increased and the light interception rate decreased. In the material production and distribution, the leaf net assimilation rate (NAR) increased, assimilation allocation was reasonable, and the economic coefficient had an increasing tendency. The leaf area index reduced, the crop growth rate (CGR) decreased, dry matter accumulation significantly decreased, and the coordination between material production and distribution changed. In the present experiment condition, no significant difference of economic yield existed between the early tiller emerge treatment and the middle tiller emerge treatment, but extremely significant difference of economic yield existed between the early tiller emerge treatment and the later tiller emerge treatment. The present study indicated that the big seedlings have some extent compensation ability of tillering for the biotic and abiotic stress like the artificially specific tiller removal in the initial tillering stage, and the compensation ability exhibited in increasing the growth potential in the tillering stage, increasing the single stem leaf area and canopy light distribution in the heading stage, and delaying the last leaf senescence rate and increasing the NAR and economic coefficient in the mature stage.