The purpose of the present work was to determine the size sample in order to estimate soluble solid contents in yellow melon plot. Samples of fifty fruits were taken of fifteen yellows melon plots grown in Mossoró- Assu Agricultural Pole. Evaluation for total soluble solid contents was done in all fruit samples. The procedures used for sample size estimation were bootstrap method and classical expression with 5% and 10% of error limit. The sample sizes estimated by bootstrap method, in average, yielded estimates close to those observed in the classical expression with 10% of error limit, although in ten plots these sample sizes were greater in the bootstrap method. The sample size recommended to estimate the total soluble solid contents in cultivated plots of melon fruits is fifteen.

Seedling production is an important step for the tomato (L. esculentum) production system, being sometimes limited by cost and quality of the substrates used for this purpose. Use of agro-industrial residues, alone or in mixtures, may help reduce this problem. The potential of different mixtures of substrate including coconut dust treated with nitrogen, phosphorus and potassium (PC), commercial substrate TropstratoÒ and organic compound (CO) were evaluated in order to obtain the best source and combinations of substrates. These materials were used alone or in volumetric basis mixtures at the proportions of PC+SC (1:1); PC+CO (1:1) and PC+SC+CO (1:1:1), for seedling production of tomato cv. Salada. The randomized block design was used, with six treatments and six replications. Obtained data were aerial dry matter (MS), emergence speed index (IVE), colon diameter (DC), leaf number (NF) and seedling height (AP). The best results were obtained for CO and PC+CO. CO performance probably is due to its higher nutritional value, once its physical characteristics do not differ from the remaining treatments, especially when compared to SC and PC. CO was the best substrate for tomato seedling production, and its addition to PC enhanced the performance. The use of organic residues for tomato seedling substrate composition is an economic option which may reduce production costs, and represents an alternative for recycling and subproduct usage in agro-industry.