Development of watermelon seedlings on cattle manure and poultry litter substrates

The importance of watermelon cultivation is widely recognized on a global scale, mainly because it is predominantly grown by small- and medium-sized farmers. This is due to its easy management and reduced costs compared to other fruits and vegetables. This research aimed to analyze the initial growth of watermelon seedlings on various types of substrates, in order to identify which one contributes to greater plant development. The experiment was carried out in randomized blocks, with five treatments: T1 = commercial substrate; T2 = cattle manure; T3 = poultry litter; T4 = poultry litter + sand (2:1); T5 = cattle manure + sand (2:1). Each treatment was replicated five times, totaling 30 viable seedlings per plot. Sowing was carried out in plastic trays, suitable for the production of seedlings. We observed that the T2 and T5 treatments resulted in a higher dry mass of the roots compared to the others, indicating that cattle manure promoted plant development, stimulating greater root production. Regarding the Development Quality Index (DQI), significant differences were found between treatments T2, T5 and T1, confirming the possibility of using the alternative substrate with high quality. In addition to being an affordable and economical material for small farmers, it also contributes to the satisfactory development of plants. It is concluded, therefore, that substrates T2 and T5 achieved positive results in relation to the others. Thus, its use can be considered viable for the production of watermelon seedlings.