| Shandong, one of the largest cotton (Gossypium hirsutum L) growing provinces in China, is currently the biggest production base for hybrid seed of cotton in the nation. To meet the practical demand of cotton production in Shandong, techniques for hybrid seed production, growth parameters of hybrid cotton plants, hybrid cotton distribution, and simplified technique for hybrid cotton culture were studied with commericial hybrid cotton varieties. Results show that SCRC 15, a hybrid cotton variety, was greatly suitable for growing in Shandong. Compared with other non-hybrid cotton varieties, SCRC 15 held such advantages as rapid growth in seedling stage, predominance in both vegetative and reproductive growth, high photosynthetic (Pn) rate, and absence of mid-noon depression in Pn, which resulted in over 15% increase in lint yield. A production system for hybrid seed with a seed yield objective of 1500 kg/hm2, involving monoculture, reduced population density (3.0-3.15 plants.m"2) by increasing row spacing, and seedling transplanting was established. Based on environmental conditions and labor powers, south west of Shandong was the most suitable region for developing hybrid cotton. A cost-saving system for hybrid cotton production with low plant density and 2 non-excised vegetative branches was established, which contrasted with the conventional system with moderate plant density that employs vegetative branch removal. Concretely, a plant density of 2.25-3.0 plants/m2 for south west and 3.0-3.15 plants/m2 for south west and north Shandong were recommended, while apply the cost-saving system for growing hybrid cotton..
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