Pollen viability, pollen germination and pollen tube growth in the biofuel seed crop Jatropha curcas (Euphorbiaceae)

Abstract

The fate of pollen and pollen tubes can have a profound effect on fruit and seed production. Experiments were conducted to investigate pollen viability, in vitro pollen germination and in vivo pollen tube growth in the biofuel seed crop Jatropha curcas. It was possible to distinguish between fresh and dead pollen using 2,3,5-triphenyltetrazolium chloride (TTC). Pollen germination was significantly higher in an agar-based medium composed of sucrose, boric acid and calcium nitrate compared with the control and indole-3-acetic acid (IAA) treatments. Pollen from hermaphrodite flowers had lower viability, lower germination rates and shorter pollen tubes, with abnormal shapes, compared to the pollen from male flowers. Pollen tubes from both self- and cross-pollinated flowers entered the ovary within 8 h after pollination, thus confirming earlier reports of self-compatibility in this species.