Fig 1.
Physical and physiological changes of cowpea (Vigna unguiculata L., Walp) seeds at 28, 31, 37 and 40 days after anthesis (DAA).
A: Water content and dry weight. B: germination capacity (fresh seeds) and desiccation tolerance (dried seeds). C: vigor expressed by germination rate (1/t50) and seedling formation (aerial part, hypocotyl and radicle well developed and healthy).
Table 1.
Information of the data evaluated in cowpea seeds (Vigna unguiculata L., Walp) during maturation stages (28 to 40 DAA)*.
Fig 2.
Lifespan of the cowpea (Vigna unguiculata L., Walp) seeds harvested at 28, 31, 34, 37 and 40 DAA.
A: Germination capacity after different periods of storage. B: acquisition of seed longevity expressed by p50 (period in days when the viability of the seeds is reduced by 50%).
Fig 3.
Principal component analysis (PCA).
The dotted circle indicates the variables that most correlated at 37 DAA and 40 DAA (superior seed quality: late maturation phase). WC: Water content; DW: Dry weight; G: Germination capacity; DT: Desiccation tolerance; 1/t50: germination rate; SE: seedling formation; p50: Longevity.
Fig 4.
Phases of cowpea seed development.
The relation between the developing stages and the acquisition of seed physiological quality during maturation and late maturation.
Fig 5.
Summary diagram for cowpea (Vigna unguiculata L., Walp) grain yield performance as a function of physiological seed quality at different maturation stages.