GROWTH AND PARTITIONING OF ASSIMILATES IN TOMATO TREES DUE TO THE DIFFERENT KINDS OF MULCHING

It is proposed to evaluate the growth of tomato plants grown in soil covered with different types of material. The experiment was conducted at WG Fruit Farm in Baraúna-RN during the period from July to November 2008. The experimental design was a randomized complete block with four replications. The treat- ments were arranged in split plots. The plots were the types of ground cover: bare soil (control), black polyeth- ylene film (double-sided black), silver polyethylene film (double-sided black and silver), white polyethylene film (double-sided black and white) and black row cover (TNT), and the subplots sampling dates of plants of the hybrid tomato Mariana at intervals of fourteen days, from the seedling stage (14, 28, 42, 56, 70, 84 and 98 days after transplanting, DAT). The plants were harvested in the surface area of each plot, partitioned into leaves, stems, flowers clusters and fruit, and placed in an oven with forced circulation at 65 oC, until constant weight is gotten. The characteristics assessed were: dry matter accumulation of leaves, twigs, flower clusters, fruit, total leaf area and leaf area index. Based on the dry mass of leaves, twigs, flower clusters, fruit and total, it was quantified partition of treated tomato grown in different mulching. Mulching treatments affected the growth of tomato plants with black row cover, white polyethylene and bare soil registering the highest mean of total dry matter, leaf area and leaf area index. The maximum leaf area index was obtained at 71 DAT in the treatments with black row cover (2.88), non-covered soil (2.36), white polyethylene (2.21), 77 DAT in silver polyethylene (2.17) and black polyethylene (1.72). At the end of the cycle, the plant has accumulated a mean of 28.30%, 11.98%, 3.92% and 55.82% of dry leaves, twigs, flowers and fruit clusters, respectively. Key words: Solanum lycopersicon L, dry mass accumulation, assimilate partitioning, leaf area.It is proposed to evaluate the growth of tomato plants grown in soil covered with different types of material. The experiment was conducted at WG Fruit Farm in Baraúna-RN during the period from July to November 2008. The experimental design was a randomized complete block with four replications. The treat- ments were arranged in split plots. The plots were the types of ground cover: bare soil (control), black polyeth- ylene film (double-sided black), silver polyethylene film (double-sided black and silver), white polyethylene film (double-sided black and white) and black row cover (TNT), and the subplots sampling dates of plants of the hybrid tomato Mariana at intervals of fourteen days, from the seedling stage (14, 28, 42, 56, 70, 84 and 98 days after transplanting, DAT). The plants were harvested in the surface area of each plot, partitioned into leaves, stems, flowers clusters and fruit, and placed in an oven with forced circulation at 65 oC, until constant weight is gotten. The characteristics assessed were: dry matter accumulation of leaves, twigs, flower clusters, fruit, total leaf area and leaf area index. Based on the dry mass of leaves, twigs, flower clusters, fruit and total, it was quantified partition of treated tomato grown in different mulching. Mulching treatments affected the growth of tomato plants with black row cover, white polyethylene and bare soil registering the highest mean of total dry matter, leaf area and leaf area index. The maximum leaf area index was obtained at 71 DAT in the treatments with black row cover (2.88), non-covered soil (2.36), white polyethylene (2.21), 77 DAT in silver polyethylene (2.17) and black polyethylene (1.72). At the end of the cycle, the plant has accumulated a mean of 28.30%, 11.98%, 3.92% and 55.82% of dry leaves, twigs, flowers and fruit clusters, respectively.