Abstract
Despite the importance of the nutrients, mainly nitrogen, in the formation and chemical composition of the seeds, little research has been done to verify the relationship between the nutrients supplied to the plants and the quality of the seeds produced. The objective of this study was to evaluate the influence of nitrogen doses and splitting on yield, quality and macronutrients content in zucchini seeds. Two experiments (crop 2014 and crop 2015) were installed, with thirteen treatments in the factorial scheme 4x3+1, with four nitrogen doses in top dressing (62.5; 125.0; 187.5; 250.0 kg ha-1), three splitting (1/6+1/3+1/2; 1/4+1/2+1/4; 1/3+1/3+1/3 of total dose in each split), and one treatment without N fertilization in top dressing (dose 0), with four replications. Seed production and quality and macronutrient content in seeds were evaluated. There wasn’t significant effect on number of fruits and seeds produced per plant. However, in crop 2014 the higher the doses of N in top dressing, the higher the seed weight per fruit and per plant, the weight of 100 seeds and the vigor (first count in germination test). In crop 2015, seeds with the best quality (germination and first counting) were obtained in the 1/4+1/2+1/4 splitting. The decreasing order of the macronutrient content in the seeds was N>P>K>Mg>S>Ca.
Highlights
A balanced fertilization is essential in the production of seeds, due to the fact that the nutrients participate in the seed formation, development and maturation phases, being part of the membrane constitution and in the accumulation of lipids, carbohydrates and proteins, reflecting in the size, weight and chemical composition of seeds (Carvalho & Nakagawa 2012)
Despite there is no difference in seed number per fruit, as the 100 seed weight increased with doses of N, it was observed a linear effect for weight of seeds per fruit, in all the splitting, with an increase of 36.7%, 26.9% and 28.2% in the seed production (g) per fruit in the dose 250 kg ha-1 of N compared to the control in the 1/6+1/3+1/2, 1/4+1/2+1/4 and 1/3+1/3+1/3 splitting, respectively (Figure 2A)
For seed production (g) per plant, the means were adjusted to the linear model, without interactions, with an increase of approximately 34.7% in the seed weight at the dose 250 kg ha-1 of N when compared to the control, regardless the splitting (Figure 2B)
Summary
A balanced fertilization is essential in the production of seeds, due to the fact that the nutrients participate in the seed formation, development and maturation phases, being part of the membrane constitution and in the accumulation of lipids, carbohydrates and proteins, reflecting in the size, weight and chemical composition of seeds (Carvalho & Nakagawa 2012). The nutritional requirement of the plants is more intense and nutrients are intensely translocated to seed formation. Among these nutrients, nitrogen is prominent in seed formation, as it is involved in the constitution of proteins, starch synthesis, embryo formation and reserve tissue. Nitrogen can influence the physiological quality of the seeds, but their effects vary with the environmental conditions and the stage of development of the plant in which the fertilizer application occurs (Carvalho & Nakagawa 2012)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
