Produtividade e tempo de prateleira do quiabo em função da adubação nitrogenada e época de cultivo

Abstract

Okra is a vegetable widely consumed and grown across Brazil. Despite the popularity, few studies have been conducted with okra growing and post-harvest. This study aimed to evaluate nitrogen fertilization effect on okra agricultural characteristics and postharvest. To attend these objectives, the research was divided into two chapters. Chapter I verified the nitrogen effect in two growing seasons on okra agronomic characteristics. In Chapter 2, was evaluated the conservation and postharvest quality of okra fruits, packed in different containers and temperatures along 12 days storage. Two experiments were conducted in two distinct growing seasons, from April to July and other from August to November 2015. The treatments consisted of six nitrogen rates (0, 50, 100, 150, 200 and 250 kg ha- 1). The containers used were Styrofoam tray coated with PVC film 14 micra and plastic bag 10 micra. Samples were stored at four temperatures (8, 15, 20 and 24 ° C) for seven periods of storage (0, 2, 4, 6, 8, 10, 12 days) factorial (2 x 4 x 7). The evaluated characteristics were influenced by nitrogen, increased linearly up to a dose of 250 kg ha-1 of nitrogen. The productivity of okra ranged from 6 to 16.83 t ha-1 with linear response to 250 kg ha-1 nitrogen. Plant high, chlorophyll index, weight, diameter and fruit length, were very affected by nitrogen applied, but positive responses are observed up to 250 kg ha-1. Nitrogen sources use in cerrado soils is an essential condition to okra fruits development and productivity. Harvest season affects postharvest fruit. Fruit stored in trays remain viable for longer than the stored bags. Mass loss and blackening increased with the storage time, especially in tray product viability for sale until the 12th storage day. The optimal temperature for storing fruits of okra is 8 ° C using the tray as packaging.