Physiological deterioration of pigeon pea seeds during storage

Abstract

The pigeon pea appears as a good option for farmers to be used directly in food and feed and/or green manure. In spite of this potential, its cultivation area in our conditions is still incipient, mostly due to the lack of seeds of superior quality. It is known that the process of physiological deterioration of seeds varies according to species, constituting a relevant factor in seed technology. Storage problems in Brazil are still an issue and the decrease of physiological quality of seeds at this stage is considerable, especially for seeds containing high concentrations of protein (> 22%) as for the pigeon pea. In this context, this study aimed to evaluate the physiological deterioration of pigeon pea seeds stored in different containers and environments for 10 months. The completely randomized design in a factorial 2 × 4 × 6 with four replications was used. The treatments were constituted of two storage environments (natural condition of laboratory (25 ± 2°C) and refrigerator (4 ± 2°C), combined with four types of packaging (PET bottle, plastic bag, burlap bag and kraft paper) and six storage periods (0, 2, 4, 6, 8, 10 months). The physiological seed quality was determined in a timeframe of two months by the following tests: Standard Test Germination - TPG, TPG first count, accelerated aging and electrical conductivity. It is concluded that the percentage of normal germination seedlings by TPG decreases linearly along the storage period; the PET bottle and Plastic bag preserved the vigor and viability of the seeds more efficiently along the storage, being that the PET bottle for being waterproof and tightly sealed has obtained better performance; and the refrigerator-controlled environment is the most suitable for storage of the pigeon pea among the tested environments. Key words: Cajanus cajan L., seed quality, physiological deterioration, preservation, packaging.